Dissertations / Theses on the topic 'And goat's milk'

The biochemical activity of Streptococcus thermophilus and Lactobacillus bulgaricus in a 1:1 ratio (Chr. Hansen's Lab - CH-III) were studied at 43 C in goat and cow milk during the manufacture and storage of yogurt. Determination of pH, titratable acidity, lactose content, proteolytic activity, and enumeration of the starters were performed on samples taken at hourly intervals until the yogurt became set, and after 8, 16, 24 hours, 11 and 22 days of storage at 4 C. In goat milk the number of starter culture organisms showed higher values than those in cow milk. Fermentation was considered to be finished when the pH decreased to 4.7 and 0.7% of lactic acid was produced. Those values were reached after 3 and 4 hours for goat and cow milk respectively. The values for pH in both milks were stable at 4.7 during storage at 4 C. Goat milk and goat milk yogurt had higher levels of free amino acids (12.65 mg/dl and 24.39 mg/dl respectively) than cow milk (10.31 mg/dl) or cow milk yogurt (20.20 mg/dl). During storage at 4 C free amino acids in goat milk decreased by 20%, in cow milk they increased by 70% from values found in fresh yogurt. The proteinase activity in goat milk during elaboration of yogurt was from 2 to 3 hours after incubation, was then stable until 24 hours of storage at 4 C and then decreased. No change in the proteinase activity in cow milk yogurt was seen until 4 hours of incubation for experiments 1 and 2 and 3 hours in experiment 3. During the storage at 4 C, proteinase activity in cow milk yogurt was stable. Polyacrylamide gel electrophoresis of caseins failed to reveal marked changes during the manufacture of yogurt and storage after 22 days at 4 C. However, a scanning gel densitometer showed that the area corresponding to alpha-casein decreased by 22% and for beta-casein 13.32% during the elaboration of goat milk yogurt. After 22 days of storage at 4 C, the alpha-casein fraction decreased an additional 14%, but no change was observed in beta-casein. The area corresponding to alpha- and beta-caseins decreased by 7.16 and 14.48% respectively during yogurt manufacture and an additional 6.74 and 8% during storage of cow milk yogurt. The overall results found in this study suggest that the metabolic activity of S. thermophilus and L. bulgaricus is greater in goat milk than in cow milk during elaboration and storage of yogurt.

[ES] La presencia de residuos de antibióticos en la leche y los productos derivados representa un riesgo para los consumidores. Límites Máximos de Residuos (LMRs) no se han fijado para los productos lácteos y la transferencia de antibióticos de la leche a la cuajada y al lactosuero durante el proceso de elaboración del queso apenas ha sido estudiada. El objetivo de esta tesis fue evaluar la transferencia de antibióticos de la leche al queso y lactosuero, así como la validación de las características de varios métodos de cribado para la detección de antibióticos en muestras de suero de leche. En el primer estudio, el objetivo fue validar un método UHPLC-HRMS multi-residuo utilizando el analizador Orbitrap ExactiveTM, para el cribado cuantitativo de antibióticos en muestras de leche, queso fresco y lactosuero de acuerdo con los criterios especificados en la Decisión 657/2002/CE de la Comisión. El estudio de distribución mediante el método UHPLC-HRMS indicó que la mayor parte de antibióticos se transfirieron principalmente de la leche a la fracción lactosuero (hasta el 85,9%) durante la elaboración de queso. Por tanto, los porcentajes de retención de antibióticos en la cuajada fueron inferiores al 50%, excepto en el caso del ceftiofur (59,7%) y la dicloxacilina (52,8%), y muy variables entre los distintos antimicrobianos. En la mayor parte de los casos, la distribución de medicamentos no se vio afectada por la concentración de antibióticos presente en la leche, y estuvo escasamente relacionada con la lipofilicidad de los antibióticos. En el segundo estudio, se evaluaron las características de diferentes métodos de detección de antibióticos en muestras de lactosuero de acuerdo con la Decisión 657/2002/CE de la Comisión. En primer lugar, la especificidad (porcentaje de falsos positivos) y la capacidad de detección (CCß) del método de detección de inhibidores Eclipse Farm provisto del dispositivo e-Reader y de los métodos de unión a receptores 3Aminosensor, Quinosensor, Twinsensor y Tylosensor se evaluaron en muestras de lactosuero de leche de cabras, obteniendo en general, resultados similares a los obtenidos cuando se aplican para el análisis de la leche. También se evaluaron tres bioensayos en placa microtiter y respuesta dicotómica, que contenían Bacillus subtilis, Geobacillus thermocatenulatus y Geobacillus thermoleovorans, respectivamente, para ser aplicados simultáneamente con los métodos comerciales basados en la utilización de Geobacillus. stearothermophilus var. calidolactis. Elevados valores de especificidad (98-100%) se obtuvieron cuando las muestras de lactosuero fueron tratadas térmicamente (85ºC, 10 min). Bacillus subtilis, con menores valores de CCß para quinolonas y macrólidos, fue la opción más interesante para mejorar el perfil de detección del Eclipse 100. En cuanto al sistema multiplaca Screening Test for Antibiotic Residues (STAR) que utiliza cinco microorganismos diferentes (Geobacillus stearothermophilus para betalactámicos y sulfonamidas, Bacillus subtilis para aminoglucósidos, Kocuria varians para macrólidos, Escherichia coli para quinolonas y Bacillus cereus para tetraciclinas) aplicado al lactosuero, presentó una elevada especificidad (>=98%) en la mayor parte de casos. Los valores de CCß obtenidos con el protocolo STAR en muestras de lactosuero superan el LMR establecido en la leche, aunque podría representar una adecuada herramienta en la etapa de post-cribado y reducir el número de muestras destinadas al análisis cuantitativo por LC-MS/MS. La producción de queso a partir de leche con antibióticos genera residuos en el lactosuero. Por tanto, adecuados métodos de cribado para la detección de residuos de antibióticos en este importante subproducto de la elaboración del queso permitirían el establecimiento de una apropiada estrategia de control para prevenir la presencia de antibióticos en el lactosuero y, así, evitar los posibles efectos<br>[CA] La presència de residus d'antibiòtics en la llet i els productes derivats representa un risc per a la salut del consumidor. Límits Màxims de Residus (LMRs) no s'han fixat per als productes lactis i la transferència d'antibiòtics de la llet al formatge i al sèrum durant el procés d'elaboració del formatge quasi no s'ha estudiat. L'objectiu d'aquesta tesi va ser avaluar la transferència d'antibiòtics de la llet a les fraccions formatge i sèrum, així com la validació de la resposta de diversos mètodes per a la detecció d'antibiòtics en mostres de sèrum de llet. En el primer estudi, l'objectiu va ser validar un mètode UHPLC-HRMS multi-residu utilitzant l'analitzador Orbitrap ExactiveTM, per al garbellat quantitatiu d'antibiòtics en mostres de llet, formatge fresc i sèrum, d'acord amb els criteris especificats en la Decisió 657/2002/CE de la Comissió. L'estudi de partició utilitzant UHPLC-HRMS mètode va indicar que la major part d'antibiòtics es van transferir principalment de la llet a la fracció sèrum de llet (fins al 85,9%) durant l'elaboració de formatge. Per tant, els percentatges de retenció d'antibiòtics en la quallada van ser inferiors al 50%, excepte en el cas del ceftiofur (59,7%) i la dicloxacilina (52,8%), i molt variables entre els diferents fàrmacs. En la majoria dels casos, la distribució de medicaments no es va veure afectada per la concentració d'antibiòtics present en la llet per a la producció de formatge, i va estar escassament relacionada amb la lipofilicitat dels antibiòtics. En el segon estudi, es van avaluar les característiques de diferents mètodes de detecció d'antibiòtics en mostres de sèrum d'acord amb la Decisió 657/2002/CE de la Comissió. L'especificitat (percentatge de falsos positius) i la capacitat de detecció (CCß) d'una prova d'inhibició microbiana (Eclipse Farm acoblat al dispositiu e-Reader) i d'assajos d'unió a receptors (3Aminosensor, Quinosensor, Twinsensor i Tylosensor) es van avaluar en mostres de sèrum de llet de cabra, obtenint en general, resultats similars als obtinguts quan s'apliquen per a l'anàlisi de la llet. Es van avaluar tres bioassatjos en placa microtiter i resposta dicotòmica, que contenien Bacillus subtilis, Geobacillus thermocatenulatus i Geobacillus thermoleovorans, respectivament, per a ser aplicats simultàniament amb els mètodes comercials basats en la utilització de Geobacillus stearothermophilus var. calidolactis. Elevats valors d'especificitat (98-100%) es van obtindre quan les mostres de sèrum van ser tractades tèrmicament (85°C, 10 min). Bacillus subtilis, amb menors valors de CCß per a quinolones i macròlids, va ser l'opció més interessant per a millorar el perfil de detecció del mètode Eclipse 100. Respecte al sistema multiplaca Screening Test for Antibiotic Residues (STAR) que utilitza cinc microorganismes diferents (Geobacillus stearothermophilus per a betalactàmics i sulfonamides, Bacillus subtilis per a aminoglucòsids, Kocuria varians per a macròlids, Escherichia coli per a quinolones i Bacillus cereus per a tetraciclines), va presentar una elevada especificitat (>=98%) en la major part de casos. Els valors de CCß obtinguts amb el protocol STAR en mostres de sèrum superen el LMR establit en llet. No obstant això, aquest mètode podria convertir-se en una eina adequada en el post-garbellament per a la identificació preliminar dels residus d'antibiòtics presents en el sèrum de llet i reduir el nombre de mostres destinades a l'anàlisi quantitativa per LC-MS/MS, que és un mètode més complex i car. La producció de formatge a partir de llet amb antibiòtics genera residus en el sèrum. L'adequada prestació dels mètodes de garbellat per a la detecció de residus d'antibiòtics en aquest subproducte d'elaboració del formatge permetria l'establiment d'una estratègia de control per a evitar el risc derivat de la presència d'aquestes substàncies en el sèrum, amb efectes negatius sobre la<br>[EN] The presence of antibiotic residues in milk and dairy products poses a risk for consumer health, mainly the development of antimicrobial resistance. Maximum Residue Limits (MRLs) for veterinary drugs have not been established for dairy products. Furthermore, the transfer of antibiotics from milk to cheese and whey fractions during cheese-making has been scarcely studied and, therefore, the impact of the use of whey containing antibiotics for the manufacture of foodstuffs for human and animal consumption is unknown. The aim of this thesis was to evaluate the transfer of antibiotics from milk to cheese and whey fractions, as well as the validation of the performance of several methods to screen antibiotics in whey samples. In the first study, a multiresidue UHPLC-HRMS method using the Orbitrap ExactiveTM analyser for the quantitative screening of antibiotics in milk, fresh cheese, and whey samples was validated according to Commission Decision 2002/657/EC, using samples from three different dairy matrices (milk, fresh cheese and whey) from cows, sheep and goats. The partitioning study by UHPLC-HRMS method indicated that most antibiotics were mainly transferred from milk to whey fraction (up to 85.9%) during cheese-making. Thus, retention rates in the rennet curd fraction were lower than 50%, except for ceftiofur (59.7%) and dicloxacillin (52.8%), and very variable between drugs. In most cases, drug distribution was unaffected by the antibiotic concentration present in milk for cheese production and was poorly related to the drug lipophilicity. In the second study, the performance of different methods for screening antibiotics in whey samples was evaluated in accordance with Commission Decision 2002/657/EC, by conducting three experiments focused on commercially available screening tests, microtiter plate bioassays, and a semi-quantitative multi-plate system, respectively. Specificity (false-positive rate) and Detection Capability (CCß) of a microbial inhibitor test (Eclipse Farm coupled to e-Reader device) and receptor-binding assays (3Aminosensor, Quinosensor, Twinsensor, and Tylosensor) were evaluated in whey samples from goats, having in general, similar results than those obtained when they are applied for milk analysis. Three microtiter plate bioassays with dichotomous response containing Bacillus subtilis, Geobacillus thermocatenulatus and Geobacillus thermoleovorans, respectively, were evaluated simultaneously with commercially available tests using Geobacillus stearothermophilus var calidolactis. High specificity values (>=98%) were obtained when whey samples were heat treated (85ºC, 10 min) prior to analysis. Bacillus subtilis, having lower CCß values for quinolones and macrolides, was the most interesting option to improve the detection profile of the Eclipse 100. Regarding the multiplate system Screening Test for Antibiotic Residues (STAR) using Geobacillus stearothermophilus for ß-lactams and sulfonamides, Bacillus subtilis for aminoglycosides, Kocuria varians for macrolides, Escherichia coli for quinolones and Bacillus cereus for tetracyclines, high specificity values (>=98%) were obtained in most cases. The CCß values obtained using the STAR protocol in whey samples exceed the MRL established in milk for most of the substances considered. However, this method could become an adequate tool in post-screening and reduce the number of samples destined for the quantitative analysis by LC-MS/MS, which is a more complex and expensive method. The production of cheese using milk containing antibiotics generates drug residues in whey. Thus, the suitable performance of screening methods for the detection of veterinary drug residues in this cheese-making by-product will allow the establishment of an adequate control strategy to prevent the presence of antibiotic residues in whey and to avoid the hazards associated to human and animal health and environment.<br>This research forms part of the Project AGL-2013-45147-R financed by the Ministerio de Ciencia e Innovación<br>Giraldo Gómez, J. (2020). Transfer of antibiotics from goat's milk to cheese and whey [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/155899<br>TESIS

Orientador: João Alberto Negrão<br>Banca: Marcos Veiga dos Santos<br>Banca: Heraldo César Gonçalves<br>Banca: Kléber Tomás de Resende<br>Banca: Maria Regina Barbieri de Carvalho<br>Resumo: As características sensoriais peculiares do leite de cabra como odor e sabor acentuados, muitas vezes são consideradas desagradáveis ao consumo, tornando-se fator de recusa. Dessa forma, a alimentação tem sido um fator preponderante na manipulação dos componentes do leite, principalmente com relação ao perfil lipídico, o qual implica diretamente no seu sabor e odor. Assim, este estudo teve como objetivo avaliar as diferentes porcentagens de inclusão de capim-limão (Cymbopogon citratus (DC.) Stapf) e sua influência sobre as respostas ao estresse fisiológico via administração endovenosa de ACTH. Foram avaliados o hemograma e os parâmetros: cortisol, glicose, ureia, creatinina, albumina, fosfatase alcalina, colesterol e HDL colesterol, as características sensoriais, físicas e químicas, além do perfil lipídico do leite. Foram utilizadas 44 cabras Saanen, não gestantes, em média aos 75 dias de lactação, homogêneas quanto à idade (3 anos ± 2 meses), peso total (59,17 ± 2,69 kg), escore da condição corporal (3,0 ± 0,5) e produção diária de leite (2,58 ± 0,27 kg). O estudo foi conduzido de setembro de 2009 a fevereiro de 2010. Durante 152 dias os animais foram mantidos em sistema de confinamento em quatro baias experimentais coletivas (11 cabras/baia) sob condições climáticas e estruturais semelhantes. As quatro dietas utilizadas com relação volumoso:concentrado de 53:47, foram fornecidas uma vez ao dia após a ordenha, cuja variação foi a substituição da silagem de milho pelo capim-limão: T1 controle (concentrado + 100% de silagem de milho), T2 (concentrado + 66,5% de silagem de milho + 33,5% de capim-limão), T3 (concentrado + 33,5% de silagem de milho + 66,5% de capim-limão) e T4 (concentrado + 100% de capim-limão). Observou-se efeito quadrático no consumo de matéria seca... (Resumo completo, clicar acesso eletrônico abaixo)<br>Abstract: The typical sensory characteristics of goat's milk as sharp odor and taste are often considered unpleasant to consumer, becoming factor of refusal. Thus, nutrition of goats has been a factor on manipulation of milk components, especially with regard to lipid profile, which directly affects the taste and odor of the milk. The aim of this study is to evaluate levels of lemongrass (Cymbopogon citratus (DC.) Stapf) and physiological responses to stress via intravenous administration of ACTH. In this study were evaluated the blood count and the following parameters: cortisol, glucose, urea, creatinine, albumin, alkaline phosphatase, cholesterol and HDL cholesterol, the sensory, physical and chemical properties, and lipid profile of milk. For this purpose, 44 Saanen goats were used, not pregnant at 75 days of lactation, similar for age (± 3 years 2 months), weight (59.17 ± 2.69 kg), body condition score (3.0 ± 0.5) and daily milk production (2.58 ± 0.27 kg). The study was conducted from September 2009 to February 2010. During 152 days the animals were kept in feedlot pens in four experimental collective (11 goats/pen) under similar climatic and structural conditions. Four diets with roughage: concentrate of 53:47, were fed once a day after milking, whose variation was the substitution of corn silage by lemongrass: T1 control (concentrate + 100% corn silage), T2 (66.5% concentrate + corn silage + 33.5% lemongrass), T3 (concentrate + 33.5% corn silage + 66.5% lemongrass) and T4 (concentrate + 100% lemongrass). Quadratic effect in dry matter intake as the addition of lemongrass was observed. Blood leukocytes were not affected by adding lemongrass on the diet. The weight gain and milk production were higher for treatments with 66.5 and 100% of lemongrass. Although changes have been observed in glucose... (Complete abstract click electronic access below)<br>Doutor

Made available in DSpace on 2014-06-11T19:32:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-03Bitstream added on 2014-06-13T18:43:11Z : No. of bitstreams: 1 canaes_ts_dr_jabo.pdf: 1232021 bytes, checksum: b91a2c503101be8b9464eac0744c0a39 (MD5)<br>Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)<br>As características sensoriais peculiares do leite de cabra como odor e sabor acentuados, muitas vezes são consideradas desagradáveis ao consumo, tornando-se fator de recusa. Dessa forma, a alimentação tem sido um fator preponderante na manipulação dos componentes do leite, principalmente com relação ao perfil lipídico, o qual implica diretamente no seu sabor e odor. Assim, este estudo teve como objetivo avaliar as diferentes porcentagens de inclusão de capim-limão (Cymbopogon citratus (DC.) Stapf) e sua influência sobre as respostas ao estresse fisiológico via administração endovenosa de ACTH. Foram avaliados o hemograma e os parâmetros: cortisol, glicose, ureia, creatinina, albumina, fosfatase alcalina, colesterol e HDL colesterol, as características sensoriais, físicas e químicas, além do perfil lipídico do leite. Foram utilizadas 44 cabras Saanen, não gestantes, em média aos 75 dias de lactação, homogêneas quanto à idade (3 anos ± 2 meses), peso total (59,17 ± 2,69 kg), escore da condição corporal (3,0 ± 0,5) e produção diária de leite (2,58 ± 0,27 kg). O estudo foi conduzido de setembro de 2009 a fevereiro de 2010. Durante 152 dias os animais foram mantidos em sistema de confinamento em quatro baias experimentais coletivas (11 cabras/baia) sob condições climáticas e estruturais semelhantes. As quatro dietas utilizadas com relação volumoso:concentrado de 53:47, foram fornecidas uma vez ao dia após a ordenha, cuja variação foi a substituição da silagem de milho pelo capim-limão: T1 controle (concentrado + 100% de silagem de milho), T2 (concentrado + 66,5% de silagem de milho + 33,5% de capim-limão), T3 (concentrado + 33,5% de silagem de milho + 66,5% de capim-limão) e T4 (concentrado + 100% de capim-limão). Observou-se efeito quadrático no consumo de matéria seca...<br>The typical sensory characteristics of goat’s milk as sharp odor and taste are often considered unpleasant to consumer, becoming factor of refusal. Thus, nutrition of goats has been a factor on manipulation of milk components, especially with regard to lipid profile, which directly affects the taste and odor of the milk. The aim of this study is to evaluate levels of lemongrass (Cymbopogon citratus (DC.) Stapf) and physiological responses to stress via intravenous administration of ACTH. In this study were evaluated the blood count and the following parameters: cortisol, glucose, urea, creatinine, albumin, alkaline phosphatase, cholesterol and HDL cholesterol, the sensory, physical and chemical properties, and lipid profile of milk. For this purpose, 44 Saanen goats were used, not pregnant at 75 days of lactation, similar for age (± 3 years 2 months), weight (59.17 ± 2.69 kg), body condition score (3.0 ± 0.5) and daily milk production (2.58 ± 0.27 kg). The study was conducted from September 2009 to February 2010. During 152 days the animals were kept in feedlot pens in four experimental collective (11 goats/pen) under similar climatic and structural conditions. Four diets with roughage: concentrate of 53:47, were fed once a day after milking, whose variation was the substitution of corn silage by lemongrass: T1 control (concentrate + 100% corn silage), T2 (66.5% concentrate + corn silage + 33.5% lemongrass), T3 (concentrate + 33.5% corn silage + 66.5% lemongrass) and T4 (concentrate + 100% lemongrass). Quadratic effect in dry matter intake as the addition of lemongrass was observed. Blood leukocytes were not affected by adding lemongrass on the diet. The weight gain and milk production were higher for treatments with 66.5 and 100% of lemongrass. Although changes have been observed in glucose... (Complete abstract click electronic access below)

Probiotic dairy foods, especially non- and low-fat dairy products, are becoming popular in the US. A non-fat goat's milk yogurt containing probiotics (Lactobacillus acidophilus and Bifidobacterium spp.) was developed using heat-treated whey protein concentrate (HWPC) as a fat replacer and pectin as a thickening agent. Yogurts containing non-heat treated whey protein concentrate (WPC) and pectin as well as one with only pectin were also produced. A fat-free cow's milk yogurt with pectin was also used as a control yogurt. The yogurts were analyzed for chemical composition, water holding capacity (syneresis), microstructure, changes in pH and viscosity, mold, yeast and coliform counts, and probiotic survivability during storage at 4°C for 10 weeks. The results showed that the non-fat goat's milk yogurt made with 12% HWPC (12.5% WPC solution heated at 85°C for 30 min at pH 8.5) and 0.35% pectin, had a significantly higher viscosity (P<0.01) than any of the other yogurts and low syneresis than the goat’s yogurt with only pectin added (P<0.01). After 10 weeks in storage, viscosity and pH remained constant throughout all of the yogurts. Mold, yeast, and coliform counts were negative throughout the 10 week study. Bifidobacterium spp. remained stable and counts remained above 10⁶CFU g⁻ ¹ during the 10 week storage. However, the population of Lactobacillus acidophilus dropped below 10⁶CFU g⁻ ¹ after 2 weeks of storage. Microstructure analysis of the non - fat goat’s milk yogurt determined by scanning electron microscopy revealed that HWPC interacted with casein micelles to form a more comprehensive network in the yogurt gel. The results indicate that HWPC could be used as a fat replacer to improve the consistency of non - fat goat’s milk yogurt and other products alike.

L’objectiu principal d’aquesta tesi va ser estudiar l’efecte de la intensitat de pressió (100, 200 o 300 MPa) i el moment (abans o després del salat; BS i AS, respectivament) de l’aplicació dels tractaments d’Alta Pressió (AP) sobre la capacitat de retenció d’aigua, les característiques de textura i el perfil sensorial dels formatges de cabra pressuritzats comparats amb els formatges control. En un inici, es van posar a punt les condicions d’elaboració del formatge amb l’objectiu d’aconseguir una máxima retenció de l’aigua en els formatges mitjançant mètodes convencionals. Es van estudiar diferents combinacions de temps i pressions durant el premssat, dos temps durant el salat i dos valors d’humitat relativa a la cambra de maduració. Dels resultats obtinguts, es van escollir les millors condicions per a conformar el diagrama d’elaboració òptim. La variable que va afectar els formatges de cabra en major grau va ser la intensitat de la pressió, i en menor grau el moment d’aplicació de l’alta pressió. Referent als resultats físico-químics, els foramtges tractats a 300 MPa van mostrar els valors més alts de pH i un major contingut d’humitat. Adicionalment, aquests formatges semblaven més madurats que la resta, probablement degut a la millora de les característiques de color i als valors més elevats de proteolysis. En relació als paràmetres de textura, els formatges tractats a 300 MPa van obtenir valors més baixos de fermesa i més elevats de deformació en el punt de fractura en comparació amb el control i la resta de formatges pressuritzats. Observant les mostres tractades a 100 i 200 MPa, són remarcables algunes diferències significatives pel que fa al moment, indicant que els formatges AS van obtenir valors més baixos de fermesa en el punt de fractura al dia 30 de maduració. Els micrògrafs es van quantificar per a analitzar la microstructura, els resultats de la qual van apuntar als formatges tractats a 300 MPa com els de valors de porositat més baixos i en canvi, mostrant valors d’àrea lipídica més elevats que la resta del formatges. Les puntuacions sensorials més elevades van ser per als formatges tractats a 300 MPa, majorment pel que fa als atributs de textura, donant lloc a formatges amb millor palatibilitat i sensació en boca. Els perfils de retenció d’aigua dels formatges de cabra es van veure afectats en major grau per la intensitat de la pressió aplicada i només lleugerament pel moment d’aplicació dels tractaments. Els formatges tractats a 300 MPa van alliberar una quantitat més elevada de W1 (aigua lliure) en tots els punts de mostreig. Encara que es van observar petites oscil·lacions en els valors de W3 (aigua lligada) durant els primers estadis de maduració, els formatges tractats a 300 MPa van finalitzar la seva mauració amb valors més elevats de W3, juntament amb els formatges control, els quals van donar lloc a formatges amb una elevada capacitat de retenció d’aigua comparat amb els formatges tractats a 100 o 200 MPa. La majoria de les mostres van assolir l’equilibri pel que fa al contingut de sal entre les parts externes i internes del formatge al punt òptim de maduració establert per a aquests formatges (dia 30). Pel que fa als efectes de la pressió, els formatges pressuritzats, especialment els tractats a 300 MPa van destacar per mostrar una elevada penetració de la sal a dia 1, obtenint valors més elevats en la part interior del formatge comparat amb el control i la resta de mostres pressuritzades. Mentres que el altres formatges pressuritzats i el control no van aconseguir l’equilibri de l’homogeneització de sal en el formatge fins al dia 30, els formatges tractats a 300 MPa van mostrar una ràpida difusió de la sal durant la maduració assolint valors similars a les dues parts analitzades del formatge (interior i exterior) a dia 7. En aquest estudi, els tractaments d’alta pressió van afectar al perfil volàtil dels formatges, augmentant l’abundància de diversos compostos en el cas de 300 MPa, i per altra banda disminuint els valors d’alguns compostos en el cas de 100 i 200 MPa. Tenint en compte els resultats obtinguts, sembla ser que applicant pressions de 300 MPa als formatges de quallada enzimàtica de cabra es podrien aconseguir formatges de noves textures i aromes. Aquesta tecnología podria proporcionar la possibilitat de crear nous tipus de formatge de caracterísitques sensorials i comercials millorades, éssent més atractius pels consumidors i aportant factors beneficiosos com ara un estalvi econòmic important.<br>The overall goal of the present PhD thesis was to study some factors related to the choice of pressure intensity (100, 200 or 300 MPa) and the moment of high-pressure (HP) treatments application (before and after brining; BS and AS respectively) that could influence water binding, textural characteristics and sensory profile of pressurized goat’s milk cheeses compared with the control cheeses. First of all several cheese making productions were carried out in order to tune up the manufacture conditions, especially pursuing the goal of major water binding by conventional methods. Different pressure and time conditions were tested during pressing, two different brining times and two different relative humidity values in the ripening room were studied. From these works, the best conditions retaining higher moisture content were chosen and applied to cheese manufacturing. Results indicated that pressure intensity was the variable which most affected goat’s milk cheeses, and in a lesser extent the moment of application. In regards to physic-chemical characteristics, 300 MPa HP-treated cheeses showed highest pH values and moisture content. Additionally, these cheeses appeared as much more ripened than others, probably due to color enhanced characteristics and higher proteolysis values. In relation to textural parameters, pressurized cheeses at 300 MPa were less firm and account for higher strain values compared with the control and the rest of pressurized cheeses. Significant differences referring to high-pressure treatments at different moments of brining appeared in 100 and 200 MPa cheeses, resulting AS samples in lower fracture stress (σ t) values at day 30 of ripening. Micrographs were quantified and the microstructure of cheese analyzed obtaining a different microstructure determined by low levels in porosity, especially in 300 MPa cheeses. At the end of ripening, higher lipidic area was another characteristic attributed to 300 MPa cheeses compared to the rest of cheeses. Cheeses high-pressure treated at 300 MPa received a significantly higher overall grade than did other samples, mostly with respect to textural parameters, leading to better mouthfeel cheeses as punctuated by panelists. Internal moisture profiles of goat’s milk cheeses were affected in a great manner by pressure intensity applied and in a lesser extent, by the moment of HP application. 300 MPa cheeses showed greater amounts of W1 (free water) released at all sampling points during ripening. Although little oscillations of W3 were found at first stages of ripening, 300 MPa samples finished their ripening with major amounts of W3, together with the control cheese, showing both samples a better binding of water at the optimum ripening point compared with 100 and 200 MPa cheeses. Most of samples reached the equilibrium in regards to the salt content between inner and outer parts of cheese at the determinate optimum ripening point for cheeses in this study (day 30). Regarding the pressure effect, HP samples, especially 300 MPa cheeses revealed a greater penetration of salt at day 1, showing higher values than control and the rest of pressurized cheeses in the inner part of cheese. While control or other pressurized cheeses did not reach salt uptake equilibrium before day 30, 300 MPa cheeses revealed a faster diffusion of salt during ripening obtaining similar values between both cheese parts studied (inner and outer) at day 7 of ripening. No large effect can be observed in high-pressure treated-samples respect to the moment of brining and the salt content. In this study, HP-treatments caused several changes on the overall amount of volatile compounds found in goat’s milk cheeses. While pressures of 300 MPa seemed to increase total amount of volatile compounds, cheeses treated at 100 and 200 MPa revealed lower levels compared with the control cheese leading to an impoverished volatile profile. The absence or presence of several compounds in 300 MPa treated-cheeses modified its volatile profile enhancing it by minimizing the mouldy or sharpness and goaty notes of 300 MPa. It seems that novel textures and flavors, certainly due to the better water binding could be developed by HP processing applying 300 MPa HP-treatment. This technology may provide new textures to traditional cheeses or even the possibility to create novel types of cheese enhancing their commercial characteristics being more appealing to consumers and providing beneficial factors, economically speaking.

Consumer demand for fresher and minimally processed foods has brought about a movement to find effective, non-thermal processing technologies for the treatment of milk. The influence of temperature on bacterial reduction in UV irradiated milk was tested. Commercially processed skim, reduced fat (2%), and whole milk samples were inoculated with a naladixic acid resistant E. coli O157:H7 surrogate (ATCC 25922), maintained at or brought to 4oC and 20oC, respectively, and then exposed to a UV light dose between 5.3-6.3 mJ/cm2 for approximately 1.5 sec using the CiderSure 3500 apparatus (FPE Inc., Macedon, NY). Bacterial concentrations before and after UV exposure were enumerated and the results indicated that processing temperature was not significantly related to bacterial reduction (p > 0.05). The results did indicate that skim milk samples had a greater bacterial reduction, regardless of processing temperature compared to reduced fat milk and whole milk samples (p < 0.05). Solids such as milk fat, protein, lactose and minerals, in the milk have a greater effect over bacterial reductions than processing temperatures. Traditional goat cheeses are produced using unpasteurized milk, which increases the food safety concerns for these types of products. Fresh goat's milk was inoculated to 107 cfu/ml with Listeria monocytogenes (L-2289) and exposed to UV light using the CiderSure 3500 apparatus. Inoculated milk was exposed to an ultraviolet dose range between 0 and 20 mJ/cm2 to determine the optimal UV dose. A greater than 5-log reduction was achieved (p < 0.0001) when the milk was processed 12 times for a cumulative exposure time of roughly 18 sec and a cumulative UV dose of 15.8 +/- 1.6 mJ/cm2. The results of this study indicate that UV irradiation could be used for the reduction of L. monocytogenes in goat's milk. Organoleptic consequences of goat's milk treated with UV technology were assessed. Olfactory studies were conducted and a highly significant difference was determined between the odor of fresh goat's milk and UV processed milk (p < 0.05). The extent of lipid oxidation and hydrolytic rancidity was measured by thiobarbituric acid reactive substances (TBARS) and acid degree values (ADVs). Results indicated that as the UV dose increased, there was a significant increase in TBARS values and ADVs of the milk samples (p < 0.05). Milk samples were processed using the UV processor under the same conditions as previously described without exposure to the UV source to determine if the agitation from pumping was causing off-flavors by way of hydrolytic rancidity. The ADVs from these samples increased at the same rate as the UV irradiated samples; however, sensory studies indicated that the increase of free fatty acids (FFA) was not enough to cause detectable off-odors in the milk. Solid phase microextraction and gas chromatography (SPME-GC) was utilized to quantify the production of volatile compounds that were formed due to UV processing. The formation of pentanal, hexanal and heptanal was identified after as little as 1.3 mJ/cm2 UV dose. Peak areas were measured and analyzed after 7.8 mJ/cm2 and 15.6 mJ/cm2 and were determined to increase significantly as UV dose increased (p < 0.05). The chemical analyses supported the findings from the olfactory studies. The outcome of this research showed that UV irradiation at the wavelength 254 nm, was detrimental to certain chemical properties of fluid milk. The properties that were perceived as negative in fluid milk may be considered an attribute in certain types of cheese and future studies in the cheese production sector should be considered. Other applications for this technology could be for use in developing countries where milk is not typically processed because of the high costs of thermal pasteurization. On-farm applications for the treatment of replacement milk should also be considered.<br>Ph. D.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-07-03T20:45:36Z No. of bitstreams: 1 MARIA VERÔNICA MONTEIRO MARINHO - DISSERTAÇÃO PPGEA 2011..pdf: 14161012 bytes, checksum: 98f60a63c6ac5eb3a86397eec9d5976f (MD5)<br>Made available in DSpace on 2018-07-03T20:45:36Z (GMT). No. of bitstreams: 1 MARIA VERÔNICA MONTEIRO MARINHO - DISSERTAÇÃO PPGEA 2011..pdf: 14161012 bytes, checksum: 98f60a63c6ac5eb3a86397eec9d5976f (MD5) Previous issue date: 2011-09<br>Capes<br>O consumo do leite de cabra e de seus derivados é crescente, tendo-se como base, sua qualidade nutricional; no entanto, o sabor forte e marcante tem aceitabilidade reduzida induzindo rejeição em boa parte dos consumidores. A produção de iogurte a partir do leite de cabra combinado com polpa de frutas, pode melhorar as características sensoriais próprias do leite, mascarando seu odor característico, melhorando os teores nutricionais e, por consequência, aumentando a comercialização e o mercado. Assim sendo, objetivou-se, com esta pesquisa, a elaboração e a avaliação sensorial, química, física, físico-química e reológica de iogurte de leite de cabra adicionada de polpa de umbu {Spondias tuberosá). Foram utilizados, na elaboração das amostras, iogurte de leite de cabra, polpa de umbu, adicionada nas proporções de 10, 15 e 20%, e sacarose. Realizou-se a caracterização química, física e físico-química da polpa do umbu utilizada na elaboração das amostras. Os dados das avaliações químicas, físicas e físico-químicas da polpa foram expressos em média simples. Nas avaliações químicas, físicas e físico-químicas dos iogurtes os dados foram tratados de acordo com o delineamento inteiramente casualizado com três repetições, utilizando-se o programa Assistat. Nos iogurtes elaborados realizou-se a análise sensorial por meio de uma escala hedônica de nove pontos, na qual foram avaliados os atributos de consistência, sabor, cor, aroma, aparência, acidez e doçura e aplicados testes de aceitação; os dados foram tratados pelos programas Consensor 1.1 e Assistat, com comparação entre as médias, pelo Teste de Tukey. O estudo do comportamento reológico dos iogurtes foi realizado nas temperaturas 5, 10 e 15 °C, com leituras realizadas emviscosímetro e os dados ajustados com os modelos de Ostwald de Waelle (Lei da Potência), Casson e Mizrahi-Berk. A polpa de umbu apresentou valores de pH, acidez total titulável, sólidos solúveis totais, ácido ascórbico e teor de água, próximos aos valores reportados em literatura; em relação à cor, apresentou predominância do matiz amarelo. Para os iogurtes com diferentes concentrações de polpa de umbu o que apresentou as maiores notas médias em todos os parâmetros da avaliação sensorial, foi o iogurte de leite de cabra com 10% de polpa de umbu. Com base nos valores do pH, os iogurtes foram classificados como alimentos ácidos; em relação aos parâmetros acidez total titulável e ácido ascórbico, o iogurte de leite de cabra, com 10% de polpa de umbu, apresentou os maiores valores; não houve diferença significativa entre as formulações em relação aos sólidos solúveis totais (°Brix), proteínas, lipídios e atividade de água. Os iogurtes de leite de cabra com polpa de umbu apresentaram comportamento de fluido não newtoniano com características pseudoplásticas. Os modelos reológicos de Ostwald de Waelle, Casson e Mizrahi-Berk representaram satisfatoriamente o comportamento reológico dos iogurtes de leite de cabra com diferentes concentrações de polpa de umbu. O aumento no percentual de polpa de umbu adicionada reduziu as viscosidades aparentes dos iogurtes.<br>The consumption of goat milk and its derivatives is growing, due to its nutritional quality. However, its strong flavor has reduced acceptability in a considerable part of the consumer market. The production of yogurt from goat milk combined with fruit pulp can improve the sensory traits of the former by masking its characteristic aroma, improving nutritional content, thereby increasing its commercialization and market share. Thus, this study aimed at the development and sensory, chemical, physical, physico-chemical and rheological assessment of yogurt from goat's milk added to umbu pulp {Spondias tuberosa). Samples of goat milk yogurt and umbu pulp, added in proportions of 10, 15 and 20%, and sucrose, were used to elaborate the samples. We carried out the chemical, physical and physicochemical characterization of umbu pulp used in sample preparation. Data from chemical, physical and physicochemical assessments of the pulp were expressed as means. In the chemical, physical and physicochemical evaluations of the yogurts, data were analyzed in accordance with a randomized design with three replications using the Assistat program. In prepared yogurts, sensory evaluation was conducted using a nine-point hedonic scale, where we assessed consistency, flavor, color, aroma, appearance, acidity and sweetness, applying acceptance testing. Data were analyzed with Consensor 1.1 and Assistat programs, and means compared by applying Tukey's test. The study of rheological behavior was performed at 5, 10 and 15 °C, with readings performed in a viscometer and data fit to Ostwald the Waelle (Power Law), Casson, and Mizrahi-Berk models. The umbu pulp showed pH, titratable acidity, soluble solids, ascorbic acid and moisture content close to values reported in the literature, and, in terms of color, exhibited a predominantly yellowness. For yogurts with different concentrations oíumbu pulp, goat's milk (10% umbu pulp) displayed the highest mean scores in ali sensory parameters. Based on pH values, yogurts were classified as acidic foods; with respect to titratable acidity and ascorbic acid, yogurt from goat's milk with 10% umbu pulp exhibited the highest values; there was no significant difference between the formulations in terms of soluble solids (°Brix), proteins, lipids and water activity. Goat milk yogurt with umbu pulp showed non- Newtonian fluid behavior with pseudoplastic characteristics. Ostwald the Waelle, Casson, and Mizrahi-Berk rheological models adequately represented the rheological behavior of goat milk yogurt with different concentrations of umbu pulp. The increased percentage of umbu pulp reduced the apparent viscosity of the yogurts.

Milk expression of recombinant proteins of pharmaceutical value in transgenic dairy animals is an emerging solution for molecules that cannot be made efficiently using the standard bioreactor platform. However, the expression of large quantities of recombinant proteins in the mammary gland can result in phenotypes with compromised lactation physiology. These negative consequences have been vaguely described in the literature and, in most cases; they have not been studied in depth with view to understanding the mechanisms of mammary disruption by transgene expression. Therefore, using a transgenic herd of goats expressing recombinant human butyrylcholinesterase, the main goals of this research were to: a) study the lactation performance and basic milk parameters; b) assess milk composition; c) explore the integrity of epithelial tight junctions, endoplasmic reticulum stress and accelerated cell death; d) investigate delayed lactogenesis; and e) assess the effects of "compensatory treatments" on transgenic lactation performance. Our findings showed that transgenic lactations were characterized by a slow/delayed start of milk production, a relatively normal milk volume at peak and a premature shutdown of milk production compared to controls. These compromised productivities were associated with a disrupted lipid secretion at the level of the secretory epithelium, and a dramatic raise in the presence of phagocytes in milk that was not associated with mammary infection. Milk composition studies indicated that transgenic goats produce lower quantities of caseins and short chain fatty acids. Through determination of serum album presence and Na:K ratio in milk we established the development of permeable tight junctions as an apparent mechanism of lactation disruption in the transgenic animals. Delayed expression of α-lactalbumin was proposed as a major determinant of the delayed lactogenesis observed in the tra<br>L'expression des protéines recombinantes de valeur pharmaceutique dans la glande mammaire des animaux transgéniques est une solution émergeante pour les molécules qui ne peuvent pas être produites efficacement par les bioréacteurs standards. Toutefois, l'expression de grandes quantités de protéines recombinantes dans la glande mammaire peut entraîner des phénotypes avec une physiologie de la lactation compromise. Ces conséquences négatives ont été vaguement décrites dans la littérature et, dans la plupart des cas ; elles n'ont pas été étudiées en profondeur pour comprendre les mécanismes qui perturbent la glande mammaire suite à l'expression des transgènes. Par conséquent, en utilisant un troupeau de chèvres transgéniques qui expriment la forme recombinée de la butyrylcholinesterase humaine, les principaux objectifs de cette recherche étaient: a) d'étudier la performance de la production laitière et les paramètres de base du lait; b) d'évaluer la composition du lait; c) d'explorer l'intégrité des jonctions serrés épithéliales, le stress du réticulum endoplasmique (RE) et la mort cellulaire accélérée; d) d'enquêter sur la lactogénèse retardée; et e) d'évaluer les effets des "traitements compensatoires" sur la performance de la production laitière des chèvres transgéniques. Nos résultats ont démontré que les lactations transgéniques étaient caractérisées par un départ lent/retardé de la production laitière, un volume de lait relativement normal au pic de la production et un arrêt prématuré de la production laitière par rapport aux contrôles. Ces productivités compromises étaient associées à une perturbation de la sécrétion des lipides au niveau de l'épithélium sécrétoire et une augmentation dramatique des phagocytes dans le lait qui n'était pas associée à une infection mammaire. Les études sur la composition du lait ont indiqués

In conditions where supplementation of poor quality diets is a major challenge, forage legumes such as Sericea lespedeza can be a good alternative supplement for protein at lower cost than most commercial concentrates. From studies done on Sericea lespedeza it is found plausible and valuable to supplement urea with Sericea lespedeza to strategically combat the deleterious effect of condensed tannins in the Sericea lespedeza and provide nitrogen in the rumen. This study was aimed to evaluate the effect of replacing sunflower oilcake with urea (a rumen degradable protein RDP source) or Sericea lespedeza (rumen undegradable protein RUP source) mixed with urea as nitrogen/protein sources on nutrient utilization, milk yield and milk composition of Saanen dairy goats. A digestibility and lactation study were conducted at the University of Pretoria Research Farm and chemical analysis performed at the University Nutrilab. A 30 days digestibility study was conducted on male Saanen goats after the lactation study, with 23 days adaptation and 7 days data collection period. Nine male goats were randomised and allocated to the three treatments in metabolism cages. In the lactation study 36 dairy goats were blocked according to milk collected on first month of lactation into high, medium and low milk yielders, then allocated to the three treatments of total mixed rations containing sunflower oilcake (T1) at 7% main protein source, T2 (urea at 1%) and T3- Sericea lespedeza at 12.5% mixed with urea according to a complete randomised block design (CRBD). Milk samples were collected from individual goats monthly at two consecutive milking’s. The samples were analysed for milk fat, protein, lactose, somatic cell count and milk urea nitrogen using a Milko-Scan analyser (at Irene Lacto lab). In the digestibility study, dry matter intake was significantly higher for goats fed on Sericea lespedeza with urea (T3) diet than goats fed on T1 and T2 diet. Goats on T3 diet had also significantly higher organic matter and crude protein intake than those goats fed on the other two TMR diets. The results also shows that the mean daily milk yields for the goats in the T1, T2 and T3 were 2.56, 2.46 and 2.52 kg per day respectively. T2 group had higher milk fat % (3.61) and higher milk urea nitrogen (MUN - 25.70 mg N/dl) than the other two treatments. T1 had significantly higher milk protein %. There was a great difference in milk composition of the afternoon milk as compared to the morning milk. The three TMRs had no significant difference in the nitrogen utilization and nitrogen excretion. It is then concluded that Sericea lespedeza mixed with urea can be used as subsititutes for sunflower oilcake in the diets of dairy goats since no negetive effect was found. However further investigations are needed.<br>Dissertation (MSc Agric)--University of Pretoria, 2017.<br>DAAD-NRF<br>International Foundation for Science (IFS)<br>Animal and Wildlife Sciences<br>MSc (Agric)<br>Unrestricted

Milk protein polymorphisms have a significant influence on milk quantity and composition. Kappa-casein is of special interest due to its known relationship with milk quality. In goats, a number of allelic variants have been identified, primarily classified into two groups. Group BIEF alleles (D, E, K, and M) have been shown to have a positive effect on milk yield and technological properties, while group AIEF, the remaining alleles, have a less positive influence on milk composition. The aim of this study was to investigate genetic variation in the kappa-casein genotype of South African goats. PCR-RFLP and DNA sequencing were performed on 68 and 77 samples, respectively. In addition, 84 milk samples were analyzed for milk composition. RFLP analysis revealed that the A and/or B alleles were the most frequent in the populations studied. A frequency of 0.00 was observed for the BIEF variants using DNA sequencing. In all goat types included, the B allele was the most common, with frequencies ranging from 60% in SA Boer goats to 100% in Saanens. The B’ allele had lower frequencies of 0.357 and 0.207 in SA Boer goats and local goat types, respectively. The H allele was present at low frequencies in local goat types (10.3%) and in SA Boer goats (3.6%), but was absent in Saanens. AMOVA results indicated that most of the total variation occurred within populations (80.66%) with the remainder of the variation (FST = 0.1934; p < 0.01) occurring due to genetic differences between populations.<br>Dissertation (MSc(Agric))--University of Pretoria, 2009.<br>Animal and Wildlife Sciences<br>unrestricted

This degree has been obtained at the Faculty of Veterinary Science, Medical University of South Africa, now part of the new Faculty of Veterinary Medicine of the University of Pretoria Saanen and South African Indigenous goats were bred to kid at twelve months and annually thereafter. Milk production was recorded. Conception rates were generally more than 90 %, except for Indigenous goats in their first year. Few Indigenous goats (12 %) had twins at the first parturition, whereas 45% of Saanens had twins at 12 months of age. Twinning increased with age, and Saanen and Indigenous goats had kidding rates of 182% and 174% respectively in their third year, with Saanens later exceeding 200%. Triplets were infrequent, except in mature Saanens (9% of parturitions), and in Crossbreds (16%). Mean lactation yields were 579, 838, and 758kg for Saanens in first, second and third lactations, respectively. Lactation lengths were 283, 293 and 290 days respectively (excluding milk production beyond 300 days). Mean lactation yields for Crossbreds were 317, 446 and 438kg for first, second and third lactations. Lactation lengths were slightly shorter for Crossbreds than for the Saanens at 236, 248 and 257 days respectively. Indigenous goats were recorded at a mean milk yield of 23kg per lactation, and a mean lactation length of 94 days. Milk composition analyses for Saanens averaged 3.43, 2.88, and 4.49% for milk fat, protein and lactose, respectively. The analyses for Crossbred goats were 5.47, 3.88 and 4.81%, and for Indigenous goats were 9.33, 5.04 and 5.12%, respectively. These results showed that Crossbred goats gave less milk than Saanens, but significantly more than Indigenous goats. Milk production of Crossbred goats was found to be adequate for household requirements (subsistence purposes). In this way, the Crossbred goats were shown to be able to fulfil one of the objectives of the crossbreeding programme. The main disease identified was coccidiosis, acccompanied by pneumonia, which caused unacceptably high mortality among goat kids: 31% of Saanen, 24% of Crossbred, 38% of Three-quarter Saanen and 28% of Indigenous female kids. It is believed that this problem is largely management related, and worsened by overcrowding and the consequent poor hygiene; but the presence of rotavirus might also be significant. These aspects warrant further investigation. The main disease problem identified in mature goats was mastitis, which caused deaths of goats from peracute cases. Another important problem which became apparent after four years of age, was the incidence of squamous cell carcinoma on the udders of Saanens. Reduced exposure to the sun, by the provision of adequate shade should alleviate this problem; but the crossbreeding programme was seen to be of benefit, since no cases occurred in Crossbred goats. The experiment on heartwater aimed to assess resistance to this disease. Saanen, Indigenous and Crossbred goats were reared in a tick-free environment. In Year 1, eight goats of each type at eight months of age were given 5ml virulent heartwater blood of the Ball 3 stock. Temperatures and clinical sign were monitored. All eight Saanens were overcome by the disease, but only one Indigenous goat and two Crossbreds. In Year 2, Phase 1 of the experiment included six males and six females each of Indigenous and Crossbred goats at 11 months of age. Seven Crossbreds, but no Indigenous goats died. In Phase 2, nine Saanens were treated with tetracycline and compared to two untreated Saanens and nine untreated Three-quarter Saanen goats at 12 months of age. Both of the untreated and one of the treated Saanens died, and seven of the Three-quarter Saanens died. There were only small differences in temperature reactions; but Indigenous goats showed less clinical signs than other breeds. No differences of gender or year were apparent. These experiments indicated that Saanen goats show no genetic resistance, but that South African Indigenous goats appear to be genetically resistant to heartwater, and can transmit this resistance to a good proportion of Crossbred progeny. It has been shown therefore that it is feasible to develop a dairy goat resistant to heartwater, which could contribute significantly to the reduction of human malnutrition in rural and peri-urban communities in Southern Africa.<br>Dissertation (PhD)--University of Pretoria, 1997.<br>Production Animal Studies<br>unrestricted

VIEIRA, Marieta Maria Martins. Fisiologia, comportamento e produção de leite em genótipos caprinos sob pastejo em modelos de produção irrigados no semiárido brasileiro. 2013. 92 f. Tese (doutorado em zootecnia)- Universidade Federal do Ceará, Fortaleza-CE, 2013.<br>Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-04-22T17:39:36Z No. of bitstreams: 1 2013_tese_mmmvieira.pdf: 1675409 bytes, checksum: 2a85e97ba9c494e83a6b8546e67b458a (MD5)<br>Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-05-27T17:46:06Z (GMT) No. of bitstreams: 1 2013_tese_mmmvieira.pdf: 1675409 bytes, checksum: 2a85e97ba9c494e83a6b8546e67b458a (MD5)<br>Made available in DSpace on 2016-05-27T17:46:06Z (GMT). No. of bitstreams: 1 2013_tese_mmmvieira.pdf: 1675409 bytes, checksum: 2a85e97ba9c494e83a6b8546e67b458a (MD5) Previous issue date: 2013<br>This study aimed to assess the impact of genotype (Anglo-nubian and Saanen), type of grass (tanzania grass and tifton-85), the same management (intensive, moderate and mild) and time of year (dry, transition and wet) on physiological parameters, behavior, production and physico-chemical characteristics of goat milk kept in pasture in the semiarid region of Northeast Brazil. We used thirty-six goats than twice a week (morning or afternoon) had collected their physiological data (temperature fur, rectal temperature, respiratory rate, heart rate and sweat rate). Three collections were made of animal fur (the fur coat thickness, length, diameter and density of the hair). Environmental variables were recorded to calculate the Enthalpy of Comfort Index Animal. Analyses of the blood count, as well as measurements of cortisol, thyroxine and triiodothyronine. These goats yet had their behavior evaluated twice during the season and were also collected data their production and physicochemical characteristics for milk three times a week. Data were expressed as mean and standard error and evaluated by ANOVA and the means were compared by Tukey test (P>0.05). Milk production was analyzed by regression over the lactation. It was observed that in the transition period (morning and afternoon) and rainy (late) values of temperature and humidity were crucial to keep the goats out of the thermal comfort zone. The temperature was higher pelt for Anglo-nubian (36.7 °C), while respiratory rate (73.6 breaths.min-1) and heart (93.0 beats.min-1), length (1,85 cm) and diameter of the hair (0.048 μM) were higher for the Saanen and may indicate a condition of acclimatization or adaptation. Feeding behavior has changed with the season. As for milk production, Anglo-nubian goats produces better grazing tifton-85 or under intensive management in tanzânia grass under management moderate or mild. Already Saanen produces better grazing tanzânia grass under intensive management or tifton-85 moderate or mild under management. Other evaluations remained within the normal range. We conclude that dairy goats in semiarid environment homeothermy and maintain their milk supply with adequate physicochemical characteristics.<br>Objetivou-se avaliar o impacto do genótipo caprino (Anglo-nubiana e Saanen), tipo de gramínea (capim-tanzânia e capim-tifton 85), manejo da mesma (intensivo, moderado e leve) e época do ano (seca, transição e chuvosa) sobre os parâmetros anatomo-fisiológicos, o comportamento, a produção e as características físico-químicas do leite de cabras mantidas em diferentes modelos de produção em pasto cultivado e irrigado, na região Semiárida do Nordeste Brasileiro. Foram utilizadas trinta e seis cabras, que duas vezes por semana (manhã ou tarde) tiveram coletados os seus dados fisiológicos (temperatura do pelame, temperatura retal, frequência respiratória, frequência cardíaca e taxa de sudorese). Foram feitas três coletas do pelame dos animais (espessura da capa do pelame, comprimento, densidade e diâmetro dos pêlos). As variáveis ambientais foram registradas para o cálculo do Índice Entalpia de Conforto dos animais. Foram realizadas análises do hemograma, assim como dosagens de cortisol, triiodotironina e tiroxina. Estas cabras ainda tiveram seu comportamento avaliado durante duas vezes por época do ano e também tiveram coletados os seus dados de produção e características físico-químicas do leite durante três vezes por semana. Os dados foram expressos em média e erro padrão e avaliados por ANOVA, sendo as médias comparadas pelo teste de Tukey (P<0,05). A produção de leite foi analisada por meio de regressão ao longo da lactação. Observou-se que na época de transição (manhã e tarde) e chuvosa (tarde) os valores de temperatura e umidade foram determinantes para manterem os caprinos fora da zona de conforto térmico. A temperatura do pelame foi maior para a Anglo-nubiana (36,7 °C); enquanto que a frequência respiratória (73,6 resp.min-1) e cardíaca (93,0 bat.min-1), comprimento (1,85 cm) e diâmetro dos pêlos (0,048 μm) foram mais elevadas para a Saanen, podendo indicar condição de aclimatização ou adaptação das mesmas. O comportamento ingestivo foi alterado com a época do ano. Quanto à produção de leite, a Anglo-nubiana produz melhor em pastagem de capim-tifton 85 sob manejo intensivo ou em capim-tanzânia sob manejo moderado ou leve. Já a Saanen produz melhor em pastagem de capim-tanzânia sob manejo intensivo ou em capim-tifton 85 sob manejo moderado ou leve. As demais avaliações se mantiveram dentro dos limites considerados normais. Conclui-se que cabras leiteiras em ambiente semiárido conseguem manter sua homeotermia e produção de leite com características físico-químicas adequadas.

Thesis (MScAgric)--Stellenbosch University, 2014.<br>ENGLISH ABSTRACT: Little research has been done on natural feed additives which enhance milk production in dairy animals. Fenugreek (Trigonella foenumgraecum) is a member of the legume family and is found in India, Middle East, North Africa and South Europe. Fenugreek is used as an herb in traditional medicine to promote lactation in lactating women. It also influences the lactation performance in ruminants such as dairy cows, water buffaloes and dairy goats. Diocin is a natural saponin found in Fenugreek and has structural similarity to oestrogen, which leads to an increased release of growth hormone (GH) and ultimately milk production. Three different trials were carried out to investigate Fenugreek’s effects. Each trial consisted of three treatment groups where dairy goats were randomly assigned. Nutrifen®, NutrifenPlus® and a control treatment served as the three treatments used in this study. Forty-eight goats per treatment group were used in the first trial where the main objective was to evaluate Fenugreek’s effect on milk production and milk composition. The second trial consisted of eight goats per treatment group, where Fenugreek’s effect on the in vivo and in vitro digestibility of the feed served as the main objective of this study. In the final part of the study, growth hormone found in plasma was subsequently investigated using the same goats from trial two. Fenugreek’s effect on elevating GH levels was the objective from the third part of the study. The first trial showed promising results in terms of an increase in milk production (P = 0.01) from dairy goats using the Nutrifen® treatment and an increase in milk lactose (P = 0.03) using the NutrifenPlus® treatment. Blood cholesterol and cholesterol content found in the milk did not differ between treatments used. Apparent digestibility of the total digestible nutrients (TDN) from the feed did not increase and did not differ between treatments and therefore concluded that the dairy goats digested the different treatments with similar efficiency regardless of the additive added to the feed. Growth hormone levels found in plasma also did not differ between treatments used in the third part of the study. Variation was found in GH plasma levels and this was expected as GH levels are known to have variation within ruminants. It appears that Fenugreek used as a natural feed additive can increase the milk yield from dairy goats, which would be beneficial to the commercial dairy goat farmer. However, the process on how Fenugreek exerts its effect on milk production still remains unclear.<br>AFRIKAANSE OPSOMMING: Tot datum is min navorsing gepubliseer wat die invloed van natuurlike voer bymiddels op melkproduksie aanspreek. Fenugreek (Trigonella foenumgraecum) is ‘n peulgewas en kom voor in Indië, die Midde Ooste, Noord Afrika en Suid Europa. Fenugreek word in tradisionele medisyne gebruik om sodoende melkproduksie in lakterende vroue te verhoog. Dit verhoog ook melkprodukise in melkkoeie, waterbuffels en melkbokke. Diocin is ‘n natuurlike saponien, met sterk oestrogeniese strukturele ooreenkomste, wat in Fenugreek voorkom. Diocin lei tot die verhoogde afskeiding van groeihormoon (GH) en uiteindelik ‘n toename in melkproduksie. Drie proewe is uitgevoer ten einde die effek van Fenugreek te ondersoek. Elke proef het bestaan uit drie behandelingsgroepe en melkbokke is ewekansig aan die groepe toegedeel. Nutrifen®, NutrifenPlus® en ‘n kontrole sonder enige additief is gebruik as behandelings. Agt-en-veertig bokke is per behandeling gebruik in die eerste proef. Die doel van hierdie proef was om die invloed van Fenugreek op melkproduksie en melksamestelling te bepaal. Die tweede proef het agt bokke per behandelingsgroep gehad en het ten doel gehad om te bepaal wat die invloed van Fenugreek op die in vitro en in vivo verteerbaarheid van die voere was. In die derde proef is dieselfde bokke as die in proef twee gebruik en hier is groeihormoon vlakke in sirkulerende bloedplasma gemeet om die invloed van Fenugreek op hierdie parameter te bepaal. Resultate van die eerste proef het getoon dat melkproduksie van bokke wat Nutrifen® ontvang het betekenisvol verhoog het (P = 0.01) terwyl NutrifenPlus® gelei het tot ‘n verhoging (P = 0.03) in melk laktose vlakke. Bloed cholesterol en melk cholesterol vlakke was onveranderd. Skynbare verteerbaarheid van die totale verteerbare voedingstowwe (TVV) van die voer het nie verander (P = 0.34) met die insluiting van Fenugreek nie. Plasma groeihormoonvlakke was nie betekenisvol verskillend (P > 0.05) tussen behandelingsgroepe nie en die gebrek aan verskille kan waarskynlik toegeskryf word aan die variasie wat binne behandelings groepe opgemerk is vir hierdie parameter. Sodanige variasie in plasma groeihormoon word as algemeen beskou in herkouers. Gevolglik kan aanvaar word dat die natuurlike voerbymiddel, Fenugreek, gebruik kan word om melkproduksie in lakterende melkbokke te verhoog. Hierdie praktyk behoort voordele in te hou vir die kommersiële melkprodusent. Die proses waardeur hierdie verhoging plaasvind is egter steeds nie duidelik nie.

Thesis (MScAgric)--Stellenbosch University, 2001.<br>ENGLISH ABSTRACT: The goat is a significant domestic animal throughout the world today. With an estimated world goat population of 590 million goats in 1991 (FAO, 1991 as citied by Haenlein, 1996) it is impossible to consider the goat as insignificant. The need for milk, and it seems particularly goat’s milk, is obvious if one considers the increase in dairy goat populations over the past 20 years. Across the globe the dairy goat population has increased by 52% while in developing and developed countries, there has been an increase of 56% and 17%, respectively (Haenlein, 2000). The goat dairy industry in South Africa is still very underdeveloped, yet it holds tremendous potential for the entrepreneur willing to take the risk and do the job correctly. With the present South African financial situation the opportunities that exist for exporting value added products to countries with stronger currencies is a market with extraordinary potential. In New Zealand, the national herd consists of approximately 16000 dairy goats and 90% of the milk produced is turned to powdered milk and then exported to the East, a valuable source of foreign currency. In South Africa, the same potential exists and with some vision and hard work the dairy goat industry can make a valuable contribution to generating foreign currency. Research into the protein requirements and particularly protein degradability requirements of dairy goats is scarce, yet in recent years there has been an increased interest in the effect of protein supplementation to lactating animals (Mishra & Rai, 1996). In the work of Mishra & Rai (1996) there were benefits obtained from the use of different rumen degradable proteins for lactating dairy goat does. The does on the highly degradable protein diet had a better feed intake while the does on the low degradable protein diet gave a higher milk production. Other research on this field of study has also delivered positive results with more than one species of lactating animal that had increased levels of UDP in the diet (Robinson et al., 1991 and Christensen et al., 1993). Loerch et al. (1995) suggested that improved production by making use of rumen undegradable proteins would have no effect if crude protein were not a limiting factor in production. Pailan & Kaur (1995) and Mishra & Rai (1996) did research on lowered CP levels with increased UDP levels in lactating dairy does. They used of three diets, with the one having a 20% lower CP value but an increased level of UDP (40-45% of total CP). From this work it was concluded that a decreased CP level and an increased level of UDP is able to sustain production when compared with diets with a higher CP value. The current study consists of two trials. In the first trial the effect of weaning age and dietary protein degradability on the growth of Saanen kids was investigated. In the second trial the effect of dietary protein degradability on the production of lactating Saanen does was investigated. Fifty-eight Saanen kids were divided into groups to determine the effect of weaning age (42 vs. 70 days) on animal performance. Within the weaning day treatments, the kids were again divided into two dietary treatments. One group received a low UDP creep diet (LC) and the other a high UDP creep diet (HC). The two creep diets were formulated with rumen degradable: undegradable protein (RDP : UDP) ratios of 70:30 and 60: 40, referred to as LC and HC, respectively. However, the results from the degradability trial indicated no difference in RDP: UDP ratios for the low and high creep (72:28 and 73:27 respectively) diets. At 15.66 ± 3.09 kg the kids were taken off the creep diet and put on the growth diet. At this transition, the kids in each of the 4 established treatments were again randomly divided into two dietary treatments, a high or a low UDP growth diet, resulting in a total of eight treatments for the trial. The two growth diets were formulated with RDP: UDP ratios of 70:30 and 60:40, referred to as low growth (LG) and high growth (HG) respectively. Results from the degradability trial indicated RDP: UDP ratios for the LG and HG of 73:27 and 68:32 respectively. The growth trial was conducted over 140 days and feed intake, bodyweight change and feed conversion efficiency were compared for each of the 8 treatments. From the trial with the Saanen kids it was concluded that weaning dairy goat kids at 42 days of age when feed intake was 240 g/day resulted in similar growth rates when compared with weaning at 70 days. The two creep diets did not differ in RDP: UDP ratios and thus no conclusion can be made regarding the influence of the creep diets on the growth of Saanen kids from 20 to 80 days of age. The two growth diets did in fact differ from one another, in terms of RDP: UDP however, protein degradability had no influence on the performance of the Saanen kids from 80 to 140 days of age. Twenty-one lactating Saanen does were randomly assigned to one of three experimental diets. The treatments had two RDP: UDP ratios and two crude protein (CP) levels. Treatments were formulated to be 1) RDP: UDP = 70:30, CP = 20 % 2) RDP: UDP = 62:38, CP = 20% and 3) RDP: UDP = 62:38, CP = 18.3%. In the production trial the does were milked for 120 days, during which milk yield, milk composition, bodyweight change, feed intake and feed conversion efficiency were compared between the treatments. In the digestibility and nitrogen metabolism trial, 18 does varying from 84 to 110 days in lactation, were used to compare the experimental diets. Furthermore, the experimental diets were compared in a degradability and rate of passage trial using cannulated Dohne merino wethers. Results from the degradability trial indicated that the low UDP, low protein high UDP and high UDP diets had RDP: UDP ratios of 82:18, 78:22 and 79:21 respectively, and that the dietary protein degradability did not differ significantly between diets. Results from the production trial indicated that there was a significant difference in feed intake, dry matter (DM) intake and bodyweight. The does on the low UDP diet had significantly higher feed intakes and DM intakes and were significantly heavier at the end of the trial period. As the diets didn’t differ in protein degradability other factors must have influenced the intakes between diets. Palatability may have influenced feed and DM intake, as the low protein high UDP and high UDP diets both contained higher levels of fishmeal. No significant differences in milk production, milk composition or milk production efficiency were observed. Besides the fact that the diets did not differ in effective protein degradability, large variations in milk production between animals and low numbers of animals per treatment limited the ability to measure a difference between the treatments. Results from the digestibility trial varied between diets with the low UDP diet having a significantly lower digestibility overall than the other two diets. Reasons for the difference in digestibility could be due to the difference in rate of passage (low UDP = 0.064/hour versus the 0.044- 0.045/hour of the low protein and high UDP diets respectively) and the high ADF value of the low UDP diet. Because no difference in effective protein degradability existed between the diets it is not possible to make an accurate conclusion on whether or not the dietary protein degradability had an influence on production parameters tested in this trial.<br>AFRIKAANSE OPSOMMING: Huidiglik is die bok ‘n belangrike gedomestikeerde dier dwarsoor die wereld. Aangesien die wereldwye bokpopulasie in 1991 op 590 miljoen geraam is (FAO, soos aangehaal deur Haenlein, 1996), is dit onmoontlik om die bok as onbelangrik te beskou. Die behoefte aan melk, en dan veral bokmelk, is duidelik as mens die toename in bokpopulasies oor die afgelope 20 jaar in ag neem. Wereldwyd het die melkbokpopulasie met 52% toegeneem, terwyl dit in ontwikkelende en ontwikkelde lande met 56% en 17% onderskeidelik, toegeneem het (Haenlein, 2000). Ten spyte van die feit dat die bokmelk-industrie in Suid-Afrika nog baie onderontwikkel is, is daar geweldige potensiaal vir die entrepeneur wat bereid is om ‘n risiko te loop en die taak korrek aan te pak. Binne die huidige Suid-Afrikaanse finansiele situasie bestaan daar veral geleenthede om waardetoegevoegde produkte na lande waarvan die wisselkoers sterker is, uit te voer. In Nieu Zeeland is die nasionale kudde ongeveer 16000 melkbokke en 90% van die geproduseerde melk word verwerk na poeiermelk en uitgevoer na die Ooste. In Suid-Afrika bestaan dieselfde potensiaal en met die korrekte visie en harde werk kan die melkbok-industrie ‘n belangrike bydra lewer om buitelandse valuta te verdien. Alhoewel navorsing aangaande die proteien-degradeerbaarheidsbehoeftes van melkbokke skaars is, bestaan daar die afgelope paar jaar ‘n toenemende belangstelling in die effek van proteien supplementering aan lakterende diere (Mishra & Rai, 1996). In die werk van Mishra & Rai (1996) is die voordele om verskillende rumen degraderende proteTenvlakke in lakterende melkbokke te gebruik, aangetoon. Ooie op ‘n hoogs degradeerbare prote'fen-dieet het beter voerinnames getoon, terwyl die ooie op ’n laag degradeerbare prote'fen-dieet hoer melkproduksies gelewer het. Navorsing van hierdie aard op ander lakterende spesies het ook positiewe resultate met ‘n toename in verbyvloeiprote'ien in die dieet gelewer (Robinson et al., 1991 en Christensen et al., 1993). Loerch et al. (1995) het voorgestel dat ‘n verbeterde produksie, deur gebruik te maak van verbyvloeiprote'fn, geen effek sal he as ruprote'fen (RP) nie ‘n beperkende faktor i.t.v produksie is nie. Beide Pailan & Kaur (1995) & Mishra en Rai (1996) het navorsing gedoen op die invloed van verlaagde RP-vlakke en verhoogde nie-degradeerbare protein (NDP) vlakke in die diete van lakterende melkooie. Daar is gebruik gemaak van drie diete, waarvan die een dieet ‘n 20% laer RPinhoud, maar ‘n verhoodge NDP-vlak (40-45% van totale RP) gehad het. Vanuit hierdie werk is die gevolgtrekking gemaak dat ‘n verlaging in RP-vlak en ‘n verhoging in NDP-vlak dieselfde produksie kan onderhou, soos met ‘n hoer RP-inhoud. Die huidige navorsing bestaan uit twee proewe. In die eerste proef is die effek van speenouderdom en dieet-prote'fen-degradeerbaardheid op die groei van Saanen-lammers ondersoek. In die tweede proef is die effek van dieet-proteien-degradeerbaardheid op die produksie van lakteerende Saanen melkbokke ondersoek. Agt-en-vyftig Saanen-lammers is verdeel in twee speenouderdom-behandelings, nl. ‘n 42 dae (42) en ‘n 70 dae (70) speenouderdom. Binne hierdie speenouderdom-behandelings is die lammers verder verdeel in twee dieet-behandelings. Die een groep het ‘n lae NDP kruiprantsoen (LK) en die ander ‘n hoe NDP kruiprantsoen (HK) ontvang. Die twee kruiprantsoene was geformuleer om rumen degradeerbare proteien (RDP): NDP verhoudings van 70:30 (LK) en 60:40 (HK) te bevat, maar die resultate van die degradeerbaarheidsproef het aangetoon RDP: NDP verhoudings van 77:23 (LK) en 78:22 (HK). Die lammers is vanaf die kruipdieet oorgeplaas op ‘n groeidieet by ‘n gemiddelde lewende massa van 15.99±3.09 kg. Tydens hierdie oorplasing is die lammers van die vier bestaande behandelings verdeel in ‘n verdere twee dieetbehandelings, nl. ‘n hoe of ‘n lae NDP groei-dieet (LG en HG onderskeidelik), met die gevolg dat ‘n totaal van agt behandelings in hierdie proef bestaan het. Die twee groeidiete is geformuleer met RDP: NDP verhoudings van 70: 30 (LG) en 60: 40 (HG) onderskeidelik, maar die resultate van die degradeerbaarheidsproef het aangetoon RDP: NDP verhoudings van 78:22 (LG) en 72:28 (HG). Die groeiproef is uitgevoer oor 140 dae en voerinname, verandering in liggaamsgewig en voeromsettingsdoeltreffendheid (VOD) is vergelyk tussen die agt behandelings. Uit die lammerproef is die gevolgtrekking gemaak dat boklammers wat op 42 dae gespeen is, wanneer voerinname 240g/dag is, soortgelyke resultate i.t.v. groeitempo lewer as lammers wat op 70 dae gespeen is. Die twee kruiprantsoene het nie van mekaar in RDP: NDP verskil nie en dus kan geen gevolgtrekking gemaak word omtrentdie invloed van dieet-protel'en-degradeerbaarheid op die groei van Saanen boklammers van 20 tot 80 dae ouderdom. Die twee groei diete het van mekaar verskil in RDP: NDP maar dieet-proteien-degradeerbaardheid het geen invloed op die groei van die Saanen boklammers van 80 tot 140 dae ouderdom gehad nie. Een-en-twintig lakterende Saanen-ooie is ewekansig in drie groepe. Die behandelings het twee RDP: NDP-verhoudings en twee ruprotei'en (RP) -peile ingesluit. Behandelings was 1) RDP: NDP = 70:30, RP = 20% 2) RDP: NDP = 62:38, RP = 20% en 3) RDP: NDP = 62:38, RP = 18.3%. Tydens hierdie produksieproef is die ooie vir 120 dae gemelk en die melkopbrengs, melksamestelling, verandering in liggaamsgewig, voerinname en VOD bepaal en vergelyk tussen behandelings. In die verterings- en stikstofmetabolismeproef is 18 ooie gebruik om die diete te vergelyk. Verder is die diete ook vergelyk in ‘n degraderings- en deurvloeitempoproef met gekannuleerde Dohne merino hamels. Dieet-proteien-degradeerbaardheid waardes verkry uit die degradeerbaarheidsproef het aangedui dat die bepaalde RDP: NDP verhoudings was 82:18, 78:22 en 79:21 vir die lae NDP, lae prote'fen hoe NDP en hoe NDP diete, en dat daar geen verskil in dieet-prote'fen-degradeerbaardheid was tussen die drie rantsoene. Resultate van die produksieproef dui daarop dat daar verskille in voerinname, droematerialinname, en liggaamsgewig tussen die drie rantsoene was. Die ooie op die laer NDP rantsoen het ‘n hoe voer en DM inname gehad en was swaarder na 120 dae in die proef as die ooie in die ander twee behandelings. Redes vir hierdie verskille is nie as gevolg van dieet-proteiendegradeerbaarheid nie. Die smaaklikheid kon dalk ‘n rol gespeel het omdat dat die twee hoe NDP rantsoene hoer vlakke van vismeel gehad het. Daar was geen verskil in melkproduksie, melksamestelling en melkproduksiedoeltreffenheid tussen die drie behandelings. Resultate van die verteringsproef het tussen die laer NDP-rantsoen en die ander twee rantsoene gevarieer. Die rede vir die verskil in verteerbaarheid mag wees a.g.v. verskillende deurvloeitempo’s (laer NDP = 0.064/uur teenoor 0.044 - 0.045/uur vir die laeproteien en hoe-proteienrantsoene) en die ADF waarde wat van die lae NDP rantsoen verskil het van die ander twee rantsoene. Omdat die resultate van die degradeerbaarheidsproef aangedui het dat daar geen verskil in dieet-proteiendegradeerbaardheid was nie is dit nie moontlik om ‘n gevolgtrekking te maak random die invloed van dieet-proteien-degradeerbaardheid op die produksie van lakterende Saanen melkbokke nie.

In order to meet the increasing demand for food quality and safety, the control of pathogenic microorganisms from farms to consumers remains a continuous challenge. Disease has always been a critical issue in animal production, affecting animal health and wellbeing. For several decades, antibiotics and chemotherapeutic agents have been used in animal feed to treat and prevent infectious diseases or to promote growth. However, there are concerns about the risk of development of cross-resistance and multiple antibiotic resistance in pathogenic bacteria in both human and livestock. To slow the development of resistance, some countries have restricted or banned use of antibiotics in feeds. Therefore, the need to find alternatives to growth-promoting and prophylactic uses of antibiotics is of outmost importance in agriculture. Beneficial bacteria, mainly lactic acid bacteria have been effectively used previously as feed additives in livestock to manipulate the gut microbiota in order to support animal health. Therefore, the current study focused on isolation and characterisation of probiotic bacteria from raw goats milk. The first part of the study aimed at isolating and identifying potential probiotic bacteria. Bacteria from raw milk were cultured onto selective media including, M17 agar and MRS agar supplemented with 0.05 g/L cysteine-hydrochloride. A total of seventeen lactic acid bacteria were isolated, and were then identified using phenotypic assays, 16S rDNA gene sequencing and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF). Lactobacillus plantarum strains (KJ026587.1, KM207826.1, KC83663.1, and KJ958428.1) and Pediococcus acidalactici were obtained. Potential probiotic bacteria were identified based on their ability to survive in the gastrointestinal conditions that include growth at low pH and bile tolerance, production of antimicrobial compounds and adhesion to the intestinal mucosa. The second part of the study focused on in vitro screening of probiotic attributes in the isolates. Production of antimicrobial activity, ability to adhere to intestinal cells and survive in the gastrointestinal tract, as well as antibiotic susceptibility, were among the main probiotic properties that were analysed to assess functionality and safety of the isolates. The in vitro studies revealed that the five isolates were tolerant to acidic pH and high concentrations of bile salts, which are characteristics necessary for the probiotics to survive in the gastrointestinal tract. These isolates were also found to exhibit antimicrobial activity against some of the pathogens affecting the goats industry. The five selected LAB strains displayed resistance to vancomycin, gentamycin and nalidixic acid, but were susceptible to a broad range of other antibiotics. However, the antibiotics to which the isolates were resistant might not pose problems as it is unlikely to be transmissible between bacteria cells. Fluorescent microscopy analysis, revealed strong adhesion of the isolates to the ileum mucus following their staining with BacLight viability probe. This study is the first in South Africa that isolated and characterised probiotic bacteria from raw goats milk. Most studies on application of probiotics in ruminants have been performed in cows and calves, and there is very little information for lambs and goats. The results of this study suggest that the five selected bacteria could be used as potential candidates for the development of direct fed microbials and growth promoters that can be used in improving the overall health status of the goats. Formulation of the best cocktail and its use as direct fed microbials for goats will result in improved nutrition and productivity.<br>Dissertation (MSc)--University of Pretoria, 2015.<br>Microbiology and Plant Pathology<br>MSc<br>Unrestricted

Tyrimo metu naudotos laktobacilų išskyrimo, lactobacilų padermių rūgščių gamybos aktyvumo nustatymo, rauginto pieno klampumo nustatymo, bei riebalų rūgščių gamybos aktyvumo nustatymo metodikos. Darbo tikslas: Nustatyti skirtingų laktobacilų rūšių karvės ir ožkos pieno fermentacijos aktyvumą. Darbo uždaviniai: 1.Nustatyti Lactobacillus acidophilus, L. bulgaricus, L. rhamnosus, L. plantarum ir L. fermentum rūgščių gamybos aktyvumą rauginant karvės ir ožkos pieną. 2.Nustatyti ir įvertinti surauginto karvės ir ožkos pieno klampą; 3.Nustatyti skirtingų laktobacilų riebalų rūgščių gamybos aktyvumą. 4.Nustatyti Lactobacillus acidophilus, L. bulgaricus, L. rhamnosus, L. plantarum ir L. fermentum gyvybingumą rauginant pieną dvi paras. Išvados: Skirtingos laktobacilų rūšys karvės ir ožkos piene rūgštis gamino aktyviai. Didžiausiu rūgščių gamybos aktyvumu raugintame karvės piene pasižymėjo L. acidophilus, šios kultūros titruojamasis rūgštingumas 6 - ąją para buvo 220 oT, ožkos piene – L. planarum, 6 – ąją parą buvo 228 oT. Didžiausias rauginto karvės ir ožkos pieno klampumas nustatytas pieną rauginant 24 val. L. bulgaricus kultūra (atitinkamai 344,797 mPa.s ir 167,313 mPa.s). Didžiausias sočiųjų riebalų rūgščių (RR) kiekis, nuo bendro riebalų rūgščių kiekio, nustatytas karvės piene raugintame su L. bulgaricus (66,7 proc) ir L. acidophilus (62,6 proc). Didžiausias polinesočiųjų RR kiekis nustatytas pieną rauginant su L. plantarum (71,1 proc). Didžiausias sočiųjų RR kiekis... [toliau žr. visą tekstą]<br>During the research the following methods had been used: extraction of lactobacillus, identification of production activeness in lactobacillus tribe acids, tests of acidified milk tenacity and establishments in production activeness of fatty acids. Work aim: Determine fermentation activeness of different lactbacillus tribes in cow‘s and goat‘s milk. Work goals: 1.Determine activeness of production of Lactobacillus acidophilus, L. bulgaricus, L. rhamnosus, L. plantarum and L. fermentum in cow‘s and goat‘s milk. 2.Identyfy and evaluate cow‘s and goat‘s acidified milk of viscosity. 3.Determine production activeness of different lactobacillus fatty acids. 4.Identify Lactobacillus acidophilus, L. bulgaricus, L. rhamnosus, L. plantarum and L. fermentum viability fermentation milk for two days. Conclusions: Different types of lactobacillus in cow‘s and goat‘s milk produced acids actively. The biggest production of acids in acidified milk was performed by L. acidophilus, titrated acidity of this culture after 6 days was 220 oT, in goat‘s milk – L. planarum, after 6 days - 228 oT. The biggest cow‘s and goat‘s actified milk tenacity was found when milk was fermented for 24 h with the help of L. bulgaricus culture (accordingly 344,797 mPa.s and 167,313 mPa.s). The biggest ammount of fatty acids, from the overall fatty acid ammount, found in cow‘s milk which was fermented with L. bulgaricus (66,7 %) and L. acidophilus (62,6 %). The biggest ammount of polyunsaturates was found... [to full text]

Mestrado em Engenharia Zootécnica - Produção Animal - Instituto Superior de Agronomia / Faculdade de Medicina Veterinária<br>Milk yield records from 3993 lactations by 1948 goats of the Alpine and Saanen breeds, as well as their crosses were used in this study. Different productive traits (total milk yield, daily milk yield, yield up to 305 days of lactation and lactation length) and reproductive traits (age at first kidding and prolificacy) were analyzed as a function of different factors that affect milk production, such as year and season of kidding, breed, lactation number and litter size. All the factors had a significant effect on the productive and reproductive traits, including the interaction between breed and number of lactation, such that Saanen goats had the highest yield in the first lactation and dropped afterwards, while in the Alpine breed the reduction in milk yield was only observed in the fourth lactation. Crossbred goats had better results for all traits except prolificacy, with an estimated heterosis of 5 to 8% for milk production. Lactation curves were estimated with grafted polynomials (splines) as a function of the different factors studied. The estimated curves showed a good adjustment and their variability with the levels of the different factors studied was small.

Orientador: Paulo César Razuk<br>Banca: Augusto Ronchi Junior<br>Banca: Waldemar Gastoni Venturini Filho<br>Resumo: O produtor de leite de cabra, com o apoio e incentivo de entidades governamentais, privadas e ONGs; agrega tecnologia ao leite garantindo uma melhor distribuição de renda e qualidade de vida, fixando-se cada vez mais no campo. O resfriamento do leite após a ordenha é a melhor medida para retardar a proliferação natural das bactérias e sua temperatura deverá ser reduzida de 36 ºC para 4 ºC no período máximo de 2 horas em cada ordenha. O tempo transcorrido entre a primeira ordenha e seu recebimento na usina de beneficiamento deverá ser, no máximo, de 48 horas. Neste trabalho propõe-se projetar e analisar tanques de resfriamento de leite com capacidades úteis de 320, 500 e 2000 litros em aço inoxidável austenítico AISI 304, utilizando-se do coeficiente global médio (U) e das temperaturas médias de saturação do fluido de refrigeração (X) obtidos em ensaios experimentais. Um objetivo secundário foi verificar a possibilidade da utilização de caixas d'água de polietileno com a mesma capacidade dos tanques, por ser um produto acessível, de baixo custo e que atende as exigências sanitárias, visando obter um produto que possa substituir o aço inoxidável, mas descartou-se esta possibilidade, pois o fundo plano destas caixas dificultaria a retirada do produto e a limpeza. Nos cálculos envolvidos na geometria para a construção dos tanques, utilizou-se da relação entre a altura cilíndrica e o diâmetro que contemplasse respectivamente, o número... (Resumo completo, clicar acesso eletrônico abaixo)<br>Abstract: The goat milk producer, with support and encouragement of governmental and private agencies as well as NGOs, aggregate technology to milk production ensuring a better distribution of income and life quality for all his family, making it possible the maintenance of the country life. The milk cooling ater the milking process is the best alternative to delay the natural proliferation of bacteria. The milk temperature should be reduced from 36 ºC to 4 ºC in a maximum period of time of two hours for each milking. The elapsed time between the first milking and the milk delivery in the processing plant shall be at most 48 hours. In this work, we propose to design and analyze milk cooling AISI 304 austenitic stainless ateel 320, 500 and 2000 liters tanks, using the mean global coefficient (U) and mean saturation temperatures of the refrigeration fluid (X), obtained experimentally. Besides stainless steel built tanks, accessible low cost polyethylene watertanks, with same dimensions of the steel tanks, attending the necessary sanitary requirements were used, aiming for an alternative product that can replace stainless steel. However, this possibility was rejected, because its flat basis would make it hard the product removal and its cleaning. During the geometric calculations in the manufacturing of the tanks, the relationship betwwen the cylindrical height and the diameter was defined in order to provide the golden ratio and batch square... (Complete abstract click electronic access below)<br>Mestre

Due to its strength, flexibility, and biocompatibility, spider silk is a highly appealing material for applications in the medical field. Unfortunately, natural spider silk is difficult to obtain in large quantities because spiders are territorial and cannibalistic, making them impractical to farm. Synthetic spider silk proteins produced by transgenic hosts such as bacteria and goats have made it possible to obtain the quantities of spider silk needed to study it more fully and to investigate its potential uses. The spider silk proteins produced in our laboratory do not have an optimal purification method to remove all of the non-biocompatible contaminants and have not previously been tested for their biocompatibility. The first focus of this dissertation was to create goat cells that can be used to create new goats. These new goats will produce proteins that can be purified more efficiently and more completely. The second focus of this dissertation was to perform biocompatibility tests on goat-derived spider silk proteins. Prior to performing any biocompatibility tests, a method was established for removing endotoxins – an impurity that causes an immune response in the body – from the proteins. This work has shed light on areas for improvement in the silk protein purification process and laid groundwork for the production of new goat-derived proteins. These steps will help make it possible for synthetic spider silk to progress further toward becoming a viable biomaterial.

Objetivou-se avaliar o impacto do genÃtipo caprino (Anglo-nubiana e Saanen), tipo de gramÃnea (capim-tanzÃnia e capim-tifton 85), manejo da mesma (intensivo, moderado e leve) e Ãpoca do ano (seca, transiÃÃo e chuvosa) sobre os parÃmetros anatomo-fisiolÃgicos, o comportamento, a produÃÃo e as caracterÃsticas fÃsico-quÃmicas do leite de cabras mantidas em diferentes modelos de produÃÃo em pasto cultivado e irrigado, na regiÃo SemiÃrida do Nordeste Brasileiro. Foram utilizadas trinta e seis cabras, que duas vezes por semana (manhà ou tarde) tiveram coletados os seus dados fisiolÃgicos (temperatura do pelame, temperatura retal, frequÃncia respiratÃria, frequÃncia cardÃaca e taxa de sudorese). Foram feitas trÃs coletas do pelame dos animais (espessura da capa do pelame, comprimento, densidade e diÃmetro dos pÃlos). As variÃveis ambientais foram registradas para o cÃlculo do Ãndice Entalpia de Conforto dos animais. Foram realizadas anÃlises do hemograma, assim como dosagens de cortisol, triiodotironina e tiroxina. Estas cabras ainda tiveram seu comportamento avaliado durante duas vezes por Ãpoca do ano e tambÃm tiveram coletados os seus dados de produÃÃo e caracterÃsticas fÃsico-quÃmicas do leite durante trÃs vezes por semana. Os dados foram expressos em mÃdia e erro padrÃo e avaliados por ANOVA, sendo as mÃdias comparadas pelo teste de Tukey (P<0,05). A produÃÃo de leite foi analisada por meio de regressÃo ao longo da lactaÃÃo. Observou-se que na Ãpoca de transiÃÃo (manhà e tarde) e chuvosa (tarde) os valores de temperatura e umidade foram determinantes para manterem os caprinos fora da zona de conforto tÃrmico. A temperatura do pelame foi maior para a Anglo-nubiana (36,7 ÂC); enquanto que a frequÃncia respiratÃria (73,6 resp.min-1) e cardÃaca (93,0 bat.min-1), comprimento (1,85 cm) e diÃmetro dos pÃlos (0,048 &#956;m) foram mais elevadas para a Saanen, podendo indicar condiÃÃo de aclimatizaÃÃo ou adaptaÃÃo das mesmas. O comportamento ingestivo foi alterado com a Ãpoca do ano. Quanto à produÃÃo de leite, a Anglo-nubiana produz melhor em pastagem de capim-tifton 85 sob manejo intensivo ou em capim-tanzÃnia sob manejo moderado ou leve. Jà a Saanen produz melhor em pastagem de capim-tanzÃnia sob manejo intensivo ou em capim-tifton 85 sob manejo moderado ou leve. As demais avaliaÃÃes se mantiveram dentro dos limites considerados normais. Conclui-se que cabras leiteiras em ambiente semiÃrido conseguem manter sua homeotermia e produÃÃo de leite com caracterÃsticas fÃsico-quÃmicas adequadas<br>This study aimed to assess the impact of genotype (Anglo-nubian and Saanen), type of grass (tanzania grass and tifton-85), the same management (intensive, moderate and mild) and time of year (dry, transition and wet) on physiological parameters, behavior, production and physico-chemical characteristics of goat milk kept in pasture in the semiarid region of Northeast Brazil. We used thirty-six goats than twice a week (morning or afternoon) had collected their physiological data (temperature fur, rectal temperature, respiratory rate, heart rate and sweat rate). Three collections were made of animal fur (the fur coat thickness, length, diameter and density of the hair). Environmental variables were recorded to calculate the Enthalpy of Comfort Index Animal. Analyses of the blood count, as well as measurements of cortisol, thyroxine and triiodothyronine. These goats yet had their behavior evaluated twice during the season and were also collected data their production and physicochemical characteristics for milk three times a week. Data were expressed as mean and standard error and evaluated by ANOVA and the means were compared by Tukey test (P>0.05). Milk production was analyzed by regression over the lactation. It was observed that in the transition period (morning and afternoon) and rainy (late) values of temperature and humidity were crucial to keep the goats out of the thermal comfort zone. The temperature was higher pelt for Anglo-nubian (36.7 ÂC), while respiratory rate (73.6 breaths.min-1) and heart (93.0 beats.min-1), length (1,85 cm) and diameter of the hair (0.048 &#956;M) were higher for the Saanen and may indicate a condition of acclimatization or adaptation. Feeding behavior has changed with the season. As for milk production, Anglo-nubian goats produces better grazing tifton-85 or under intensive management in tanzÃnia grass under management moderate or mild. Already Saanen produces better grazing tanzÃnia grass under intensive management or tifton-85 moderate or mild under management. Other evaluations remained within the normal range. We conclude that dairy goats in semiarid environment homeothermy and maintain their milk supply with adequate physicochemical characteristics.

Made available in DSpace on 2014-06-11T19:33:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-06-15Bitstream added on 2014-06-13T19:44:26Z : No. of bitstreams: 1 rodrigues_l_dr_botfmvz.pdf: 681510 bytes, checksum: 590f90c90a98c3da3d566cdd75891f67 (MD5)<br>Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)<br>Universidade Estadual Paulista (UNESP)<br>Foram utilizadas 50 cabras (30 da raça Alpina e 20 ½ Boer + ½ Alpina), primíparas e multíparas, com peso corporal médio de 52,7±1,07 kg, avaliadas em média até 203,9±8,04 dias de lactação. Foram testados dois sistemas de produção em pasto: SP1 –suplementação concentrada e SP2 - suplementação mineral. Os animais foram mantidos em pastagem estabelecida com Panicum maximum cv. Tanzânia. O controle leiteiro foi realizado a cada 14 dias, por meio da pesagem do leite e, em determinados os teores de gordura, proteína, lactose, sólidos totais (ST), extrato seco desengordurado (ESD), nitrogênio uréico e contagem de células somáticas (CCS). Calculou-se as variáveis: tempo para atingir o pico, produção no pico (PP), produção de leite no tempo t e persistência (PS), além dos custos de alimentação em função do sistema de produção. O grupo racial e o sistema de produção em pasto influenciaram a curva de lactação. A suplementação concentrada de cabras da raça Alpina resultou em maior tempo para atingir o pico de lactação, maiores PP e PS. O teor médio de ST, proteína e ESD do leite foram influenciados pelo grupo racial, sendo que as cabras ½ BA apresentaram valores superiores em relação às cabras da raça Alpina. Os teores de lactose e ESD foram maiores no leite proveniente do SP1 em relação ao SP2. O log da CCS foi influenciado pelo sistema de produção em pasto e as cabras do SP1 apresentaram menor CCS. Observou-se influência significativa da interação entre grupo racial e sistema de produção em pasto para as porcentagens de gordura e nitrogênio uréico. No sistema de produção em pasto, cabras da raça Alpina devem ser suplementadas com ração concentrada. A suplementação com ração concentrada apresentou uma maior renda líquida total por cabra, proporcionando maior lucro ao produtor.<br>Fifty goats were used (30 Alpine and 20 ½ Boer + ½ Alpine), primiparous and multiparous, with average body weight of 52.7 ± 1.07 kg, evaluated averaging to 203.9 ± 8.04 days of lactation. Were tested two pasture on systems: SP - concentrate supplementation and SP – mineral supplementation. Animals were kept in pasture established with Panicum maximum cv. Tanzania. Milk control was performed every 14 days, by weighing milk and were determined levels of fat, protein, lactose, total solids (TS), solids non fat (SNF), milk urea nitrogen and somatic cell count (SCC) in milk samples. It was calculated some variables: time to reach peak, production at peak (PP), milk production on t time and persistence (PS), in addition, cost of food according to the production system. Breed group and pasture production system influenced the lactation curve. Concentrate supplementation of Alpine goats resulted in longer time to reach peak of lactation, higher PP and PS. Average content of TS, SNF and protein were influenced by breed group, and ½ BA goats showed higher values in relation to Alpine goats. Content of lactose and SNF observed was greater in milk of animals from PS1 compared to PS2. Log of SCC was influenced by pasture production system and goats from SP1 had lower values. It was observed influence of interaction between breed group and pasture production system for percentages of fat and milk urea nitrogen. Alpine goats, on pasture production system should be supplemented with concentrate. Concentrate supplementation showed a higher total net income per goat, and consequently, a higher profit to producer.

In Mediterranean countries, sheep and goat’s milk production has traditionally been destined for the manufacture of cheese, often as raw milk. Cheese quality is closely related to milk composition but also to hygienic aspects such as somatic cell count, bacteriology or presence of antibiotic residues, currently regulated by European legislation. The implications of the presence of antibiotic residues in milk as a result of veterinary treatments include negative effects on consumer’s health such as allergies or antibiotic resistance and problems on the manufacturing processes of fermented products. For the screening of milk samples for antimicrobial residues, there are various methods available, microbial inhibitor tests and assays based on specific receptors, both widely used, especially in farms, the dairy industry and control laboratories. Screening methods have been validated for the use in raw milk from cows, but information on the performance of these tests in sheep and goat’s milk is rather limited. The aim of this study was to evaluate the performance of some microbial and receptor-binding screening tests to detect antibiotics in sheep and goat’s milk according to Commission Decision 2002/657/EC to determine their suitability to monitor the presence of antibiotic residues in milk and establish the most convenient analytical strategy in Spain. The Detection capability (CCβ) of microbial screening tests, the BRT MRL, the Delvotest MCS SP-NT, the Delvotest MCS Accelerator and the Eclipse 100, was at or below the maximum residue limits (MRLs) for most beta-lactam antibiotics assessed and other non-beta-lactam drugs such as neomycin, tylosin, sulfadiazine and sulfadimethoxine. However, they were less sensitive in the detection of quinolones and tetracyclines at safety levels. When individual milk samples were analysed, microbiological tests showed a higher occurrence of non-compliant results in sheep milk than in goat’s milk, being related in all cases to an elevated somatic cell count (SCC). The microbiological system consisting of two complemetary microtiter plates containing Geobacillus stereathermophilus var. calidolactis and Bacillus subtilis, respectively, allows improving the detection level in sheep milk with respect to the use of a single commercial test using G. stearothermophilus, detecting some quinolone and macrolide substances more closely related to their respective MRLs. The rapid receptor-binding assays (the Betastar Combo, the Charm MRL BLTET, the SNAP Betalactam, the SNAP Tetracycline and the TwinsensorBT) were able to detect most beta-lactams and tetracyclines at or below MRLs (CCβ ≤ MRL). A higher specificity of the rapid receptor tests was obtained in all cases even when individual milk samples were analysed. Only the TwinsensorBT test presented non-compliant results when antibiotic-free milk samples from individual animals were analysed, especially in the last weeks of lactation. No cross-reactions were found when drugs belonging to antimicrobial groups other than beta-lactams or tetracyclines were present in milk. Azidiol, used as a preservative, had no effect on the performance of the rapid receptor tests. Moreover, differences between the visual and instrumental classification of the test results were not found. Taking into account the frequency of use of antibiotics commonly employed in Spain and the screening test sensitivity at MRLs equivalent to antibiotic concentrations, total detection rates have been calculated. In general, the use of a single test allows detecting 62.8-82.4 % of the antibiotics employed. For sheep milk, the total detection range achieved with microbial tests was significantly higher than that reached with rapid receptor tests. However, no significant differences between the two types of tests were found when goat's milk was analysed. In both types of milk, the simultaneous use of two screening tests with a different analytical basis increases the total detection range significantly, reaching values ≥ 90 % in some cases. However, antibiotics such as enrofloxacin, marbofloxacin, spiramycin, and streptomycin also used to treat mastitis and other infectious diseases could not be detected by the screening tests assessed. Therefore, the improvement of the analytical strategy through the periodical implementation of screening tests able to detect these substances at safety levels would be recommended.<br>Beltrán Martínez, MC. (2014). Analytical strategy for the detection of antibiotic residues in milk from small ruminants [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/48164<br>TESIS

Dissertação de Mestrado em Engenharia Zootécnica-Produção Animal<br>Os principais factores do leite de cabra com influência a nível da qualidade e rendimento do queijo são revistos. Partindo de uma análise sumária da situação da caprinicultura leiteira em Portugal, das características e aspectos nutricionais do leite de cabra, dos factores que estão na base da variação da composição do leite e da aptidão do leite para o fabrico de queijo estudaram-se os resultados das análises físico-químicas, dos últimos cinco anos, referentes ao leite de cabra fornecido à empresa Queijo Saloio – Indústria de Lacticínios S.A. Os resultados obtidos permitiram concluir que existem, nesta unidade industrial e ao longo do tempo, diferenças assinaláveis e estatisticamente significativas na variação das características físico-químicas (teores em proteína e em matéria-gorda), microbiológicas e de carácter sanitário (microrganismos e células somáticas) do leite de cabra, relevantes para o fabrico de queijo. Posteriormente, retiraram-se conclusões relativamente às alterações que os constituintes do leite induzem a nível do rendimento queijeiro. Destaca-se a importância da avaliação e controlo das características do leite como factor de melhoria da qualidade/rendimento do queijo e sugere-se a adopção de uma metodologia teórica de padronização do leite para o fabrico de queijo de cabra.<br>ABSTRACT - The main factors of the goat milk with influence on the cheese quality and yield, are reviewed. Based on a succinct analysis of the dairy goat situation in Portugal, the characteristics and nutritional aspects of the goat milk, the factors based on the variation of the milk composition and the milk quality for the production of cheese, the physico-chemical data (last five years) of the goat milk supplied to Queijo Saloio – Indústria de Lacticínios S.A. have been studied. The results obtained have enabled the conclusion that in this industrial unit and along the years there have been notable differences, statistically significant, in the variation of goat milk characteristics: physico-chemical (protein and fat content), microbiological and hygiene-sanitary (microorganisms and somatic cells), relevant for the production of cheese. Subsequently, conclusions have been obtained in what concerns the changes that the constituents of milk can induce on cheese yield. It must be emphasized the importance of the evaluation and control of the milk characteristics as a factor of quality improvement / cheese yield and it is suggested the introduction of a theoretical methodology of composition standardization of the milk for the production of goat cheese.

Orientador: Heraldo César Gonçalves<br>Banca: Edson Ramos de Siqueira<br>Banca: Mário de Beni Arrigoni<br>Banca: Claudete Regina Alcalde<br>Banca: Mauro Sartoi Bueno<br>Resumo: Foram utilizadas 50 cabras (30 da raça Alpina e 20 ½ Boer + ½ Alpina), primíparas e multíparas, com peso corporal médio de 52,7±1,07 kg, avaliadas em média até 203,9±8,04 dias de lactação. Foram testados dois sistemas de produção em pasto: SP1 -suplementação concentrada e SP2 - suplementação mineral. Os animais foram mantidos em pastagem estabelecida com Panicum maximum cv. Tanzânia. O controle leiteiro foi realizado a cada 14 dias, por meio da pesagem do leite e, em determinados os teores de gordura, proteína, lactose, sólidos totais (ST), extrato seco desengordurado (ESD), nitrogênio uréico e contagem de células somáticas (CCS). Calculou-se as variáveis: tempo para atingir o pico, produção no pico (PP), produção de leite no tempo t e persistência (PS), além dos custos de alimentação em função do sistema de produção. O grupo racial e o sistema de produção em pasto influenciaram a curva de lactação. A suplementação concentrada de cabras da raça Alpina resultou em maior tempo para atingir o pico de lactação, maiores PP e PS. O teor médio de ST, proteína e ESD do leite foram influenciados pelo grupo racial, sendo que as cabras ½ BA apresentaram valores superiores em relação às cabras da raça Alpina. Os teores de lactose e ESD foram maiores no leite proveniente do SP1 em relação ao SP2. O log da CCS foi influenciado pelo sistema de produção em pasto e as cabras do SP1 apresentaram menor CCS. Observou-se influência significativa da interação entre grupo racial e sistema de produção em pasto para as porcentagens de gordura e nitrogênio uréico. No sistema de produção em pasto, cabras da raça Alpina devem ser suplementadas com ração concentrada. A suplementação com ração concentrada apresentou uma maior renda líquida total por cabra, proporcionando maior lucro ao produtor.<br>Abstract: Fifty goats were used (30 Alpine and 20 ½ Boer + ½ Alpine), primiparous and multiparous, with average body weight of 52.7 ± 1.07 kg, evaluated averaging to 203.9 ± 8.04 days of lactation. Were tested two pasture on systems: SP - concentrate supplementation and SP - mineral supplementation. Animals were kept in pasture established with Panicum maximum cv. Tanzania. Milk control was performed every 14 days, by weighing milk and were determined levels of fat, protein, lactose, total solids (TS), solids non fat (SNF), milk urea nitrogen and somatic cell count (SCC) in milk samples. It was calculated some variables: time to reach peak, production at peak (PP), milk production on t time and persistence (PS), in addition, cost of food according to the production system. Breed group and pasture production system influenced the lactation curve. Concentrate supplementation of Alpine goats resulted in longer time to reach peak of lactation, higher PP and PS. Average content of TS, SNF and protein were influenced by breed group, and ½ BA goats showed higher values in relation to Alpine goats. Content of lactose and SNF observed was greater in milk of animals from PS1 compared to PS2. Log of SCC was influenced by pasture production system and goats from SP1 had lower values. It was observed influence of interaction between breed group and pasture production system for percentages of fat and milk urea nitrogen. Alpine goats, on pasture production system should be supplemented with concentrate. Concentrate supplementation showed a higher total net income per goat, and consequently, a higher profit to producer.<br>Doutor

Submitted by Amauri Alves (amauri.alves@ufv.br) on 2015-12-08T16:21:29Z No. of bitstreams: 1 texto completo.pdf: 830285 bytes, checksum: de44c53e0279d7598c799f67d9169a9a (MD5)<br>Made available in DSpace on 2015-12-08T16:21:29Z (GMT). No. of bitstreams: 1 texto completo.pdf: 830285 bytes, checksum: de44c53e0279d7598c799f67d9169a9a (MD5) Previous issue date: 2015-07-27<br>Conselho Nacional de Desenvolvimento Científico e Tecnológico<br>O presente estudo objetivou propor modelos de regressão aleatória multicaracterísticos (MRAM) combinando diferentes funções para descrever a produção de leite e a porcentagem de gordura e proteína do leite, em uma avaliação genética de cabras leiteiras via inferência bayesiana. Foram analisados 3.856 registros de produção de leite (MY), porcentagem de gordura (FP) e proteína (PP) no dia do controle da primeira lactação de 535 cabras Alpina e Saanen (incluindo mestiças). As análises iniciais foram realizadas utilizando MRA unicaracterísticos (MRAU), nos quais para todos os efeitos (curva média, genética aditiva e de ambiente permanente), os seguintes modelos foram considerados: terceira e quinta ordem dos polinômios ortogonais de Legendre; B-splines lineares com três (na 1°, 20° e 40° semana) e cinco (na 1°, 8°, 15°, 20° e 40° semana) nós, função de Ali e Schaeffer (Ali e Schaeffer, 1897) e função de Wilmink (Wilmink, 1987). As variâncias residuais foram consideradas heterogêneas com três classes: 1 a 3, 4 a 8 e 9 a 40 semanas de lactação. Depois da definição dos melhores MRAU para descrever cada característica (MY, FP e PP), baseado no Critério de Informação da Deviance (DIC), as funções foram combinadas para compor o MRAM (MRAM combinado). O modelo baseado na função de Ali e Schaeffer apresentou melhor ajuste para as características MY e PP, enquanto o modelo baseado nos polinômios ortogonais de Legendre de quinta ordem (Leg5) foi o melhor para descrever FP. Todos os MRA testados considerando a combinação de funções apresentaram menores valores de DIC, demonstrando a superioridade destes modelos quando comparados a outros MRAM baseados somente em uma função. Entre os MRAM combinados, aquele que considerou a função de Ali e Schaeffer para descrever MY e PP e o Leg5 para descrever FP apresentou o melhor ajuste. As estimativas de herdabilidade para MY e FP foram próximas até 20 semanas, e variaram de 0,25 até 0,54. As estimativas de herdabilidade para PP foram, em geral, maiores que as estimativas para MY e FP, variando de 0,35 até 0,51. A correlação genética entre MY e FP e entre MY e PP ao decorrer do período de lactação foram negativas, exceto para o período imediatamente após o pico de lactação. A correlação genética entre FP e PP foi positiva e aproximadamente constante durante a lactação (aproximadamente 0,54). Conclui-se que a combinação de diferentes funções em um único MRAM pode ser uma alternativa plausível para a avaliação genética conjunta de diferentes características longitudinais.<br>The present study aimed to propose multiple-trait random regression models (multiple-trait RRM) combining different functions to describe milk yield, fat and protein percent in a dairy goats genetic evaluation by using MCMC (Markov Chain Monte Carlo) Bayesian inference. Were analyzed 3,856 milk yield (MY), fat (FP) and protein (PP) percent test-day records from 535 first lactation of Saanen and Alpine goats (including crosses). The initial analyses were performed using single- trait RRM, in which for all effects (average curve, additive genetic and permanent environmental) the following models were considered: third and fifth order Legendre polynomials, linear B-splines with three (at 1, 20 and 40 weeks) and five (at 1, 8, 15, 20 and 40 weeks) knots, Ali and Schaeffer function (Ali and Schaeffer, 1987) and Wilmink function (Wilmink, 1987). Residual variances were modeled by a step function with three classes: 1 to 3, 4 to 8, and 9 to 40 weeks of lactation. After definition of the best single-trait RRM to describe each trait (MY, FP, PP) based on the Deviance Information Criterion (DIC), the functions were combined to compose the multiple-trait RRM. The model based on Ali and Schaffer function fitted better for MY and PP, while the model based on fifth order Legendre polynomials (Leg5) was the best one for FP. All tested RRM considering the combinations of functions presented lower DIC values, showing the superiority of these models when compared to other multiple-trait RRM based only on one function. Among the combined RRM, those considering Ali and Schaeffer function to describe the MY and PP, and Leg5 to describe the FP, presented the best fit. Estimates of heritability for MY and FP were close until 20 weeks, ranging from 0.25 at 0.54. The estimates of heritability for PP were, in general, higher than the estimates for MY and FP, ranging from 0.35 until 0.51. The genetic correlation between MY and FP and between MY and PP throughout the lactation period were negative, except for the period immediately after lactation peak. The genetic correlation between FP and PP was positive and approximately constant throughout the lactation (about 0.54). We concluded that combining different functions in a unique multiple-trait RRM can be an plausible alternative for joint genetic evaluation of different longitudinal traits.

Thesis (Ed. D.)--Illinois State University, 1994.<br>Title from title page screen, viewed March 27, 2006. Dissertation Committee: Robert Hemenway (chair), Jeffrey Hecht, Pamela Hardaway-Wheeler, Toni McCarty, Thomas Caldwell. Includes bibliographical references (leaves 123-134) and abstract. Also available in print.

[ES] Los residuos de antibióticos en la leche constituyen un aspecto de gran importancia para la salud pública y pueden tener un efecto negativo en la industria láctea. Para proteger al consumidor se han establecido los Límites Máximos de Residuos (LMR) para diferentes antibióticos en la leche cruda. Sin embargo, la transferencia de estas sustancias de la leche al queso ha sido poco estudiada y, por lo tanto, se desconoce el impacto de la presencia de antibióticos sobre el proceso de elaboración y la seguridad del queso. El objetivo de la tesis ha sido evaluar la transferencia de los antibióticos más empleados en el ganado caprino lechero, desde la leche a quesos curados y frescos, así como estudiar el efecto sobre el proceso de fabricación y la calidad de los quesos durante la maduración. Para alcanzar el objetivo se han realizado elaboraciones de quesos curados (60 días) a partir de leche en presencia de diversos antibióticos (amoxicilina, bencilpenicilina, cloxacilina, eritromicina, ciprofloxacina, enrofloxacina y oxitetraciclina) a niveles admisibles (LMR) y fabricaciones de leche libre de antibiótico como referencia. Los resultados obtenidos sugieren que la mayor parte de los antibióticos en la leche no afectaron al proceso de fabricación del queso. Solamente la eritromicina y oxitetraciclina incrementaron el tiempo requerido en el proceso de elaboración. Respecto a las características del queso evaluadas a diferentes tiempos de maduración (0, 30 y 60 días), las pocas diferencias encontradas se refirieron a la concentración de ácidos grasos libres, el color y las propiedades de textura, pero en su mayoría no fueron detectadas en la evaluación sensorial. Sin embargo, cantidades variables de antibióticos, se transfirieron de la leche al queso (entre 7,4 y 68%). Las quinolonas y oxitetraciclina presentaron las más elevadas tasas de retención, así como persistencia a lo largo de la maduración, con altas concentraciones de quinolonas (enrofloxacina: 148±12 µg/kg; ciprofloxacina: 253±24 µg/kg) y de oxitetraciclina (20±5,7 µg/kg) después de los 60 días de curado. En el estudio de quesos frescos, se evaluó la presencia de residuos de medicamentos en la leche pasteurizada y en los quesos frescos a partir de leche de cabra con antibióticos (amoxicilina, bencilpenicilina, cloxacilina, neomicina, eritromicina, ciprofloxacina, enrofloxacina y oxitetraciclina) a niveles de seguridad (LMR). Los resultados mostraron que altas cantidades de antibióticos, entre el 71 y el 100% de la concentración inicial en la leche cruda, permanecieron en la leche pasteurizada y que fueron transferidas al queso en gran medida, con porcentajes de retención que oscilaron entre 37,5 y 75%. Con respecto a los márgenes de seguridad de estos productos, se calcularon teniendo en cuenta diferentes grupos de edades (niños, adolescentes y adultos), y los efectos negativos de estos antibióticos sobre la salud. Los resultados indicaron que el mínimo margen de seguridad en la leche pasteurizada lo presentaron la ciprofloxacina, enrofloxacina, y eritromicina para el grupo de niños. En relación al queso fresco, se obtuvo un elevado margen de seguridad para todos los antibióticos y grupos de edad considerados, lo que sugiere que este producto probablemente no tenga efectos negativos en la salud del consumidor. Es importante enfatizar que concentraciones relativamente altas de antibióticos podrían permanecer en la leche de cabra pasteurizada y productos relacionados, como los quesos frescos y de corta maduración. La presencia de estos antibióticos podría contribuir al desarrollo y propagación de la resistencia a los antimicrobianos que actualmente constituye un grave problema a nivel mundial. Los resultados de este trabajo podrían servir a las autoridades de salud pública para evaluar si los sistemas actuales de control de antibióticos en la leche y los productos lácteos son adecuados o deberían ser revisados.<br>[CAT] Els residus d'antibiòtics en la llet animal constitueixen un aspecte de gran importància per a la salut pública, i poden tindre un efecte negatiu en la indústria làctia. Per a protegir al consumidor s'han establit els Límits Màxims de Residus (LMR) per a diferents medicaments veterinaris en la llet crua. No obstant això, la transferència d'estes substàncies de la llet al formatge ha sigut poc estudiada i, per tant, es desconeix el impacte de la presència de antibiòtics sobre el procés d'elaboració i la seguretat del formatge. L'objectiu de la tesi ha sigut avaluar la transferència dels antibiòtics més empleats en el bestiar caprí lleter, des de la llet a formatges curats i frescos, així com l'efecte sobre el procés de fabricació i la qualitat dels formatges durant la maduració. Per a aconseguir l'objectiu s'han realitzat elaboracions de formatges curats (60 dies) a partir de llet en presència de diversos antibiòtics (amoxicilina, bencilpenicilina, cloxacilina, eritromicina, ciprofloxacina, enrofloxacina i oxitetraciclina) a nivells admissibles (LMR) i fabricacions de llet lliure d'antibiòtic (control) com a referència. Els resultats obtinguts suggerixen que la major part dels antibiòtics en la llet no van afectar el procés de fabricació del formatge. Només l'eritromicina i l'oxitetraciclina van incrementar el temps requerit en el procés d'elaboració del formatge. Respecte a les característiques del formatge avaluades a diferents temps de maduració (0, 30 i 60 dies), les poques diferències trobades es van referir a la concentració d'àcids greixos lliures, el color i les propietats de textura, però majoritàriament no van ser detectades en l'avaluació sensorial. No obstant això, quantitats variables d'antibiòtics, es van transferir de la llet al formatge (entre 7,4 i 68%). Les quinolones i l'oxitetraciclina van presentar les més elevades taxes de retenció, així com persistència al llarg de la maduració, amb altes concentracions de quinolones (enrofloxacina: 148±12 µg/kg; ciprofloxacina: 253±24 µg/kg) i d'oxitetraciclina (20±5,7 µg / kg) després dels 60 dies de curació. En l'estudi de formatges frescos, es va avaluar la presència de residus de medicaments en la llet pasteuritzada i en els formatges frescos a partir de llet de cabra amb antibiòtics (amoxicilina, bencilpenicilina, cloxacilina, neomicina, eritromicina, ciprofloxacina, enrofloxacina i oxitetraciclina) a nivells de seguretat (LMR). Els resultats van mostrar que altes quantitats d'antibiòtics, entre el 71 i el 100% de la concentració inicial en la llet crua, van romandre en la llet pasteuritzada i que van ser transferides al formatge en gran manera, amb percentatges de retenció que van oscil·lar entre 37,5 i 75%. Respecte als marges de seguretat d'estos productes, es van calcular tenint en compte diferent grups d'edats (xiquets, adolescents i adults), i els efectes negatius d'estos antibiòtics sobre la salut. Els resultats van indicar que el mínim marge en la llet pasteuritzada ho van presentar la ciprofloxacina, la enrofloxacina, i l'eritromicina per al grup de xiquets. En relació al formatge fresc, es va obtindre un elevat marge de seguretat per a tots els antibiòtics i grups d'edat considerats, la qual cosa suggereix que este producte probablement no tinga efectes negatius en la salut del consumidor. És important emfatitzar que concentracions relativament altes d'antibiòtics podrien romandre en la llet de cabra pasteuritzada i productes relacionats, com els formatges frescos i de curta maduració. La presència d'estos antibiòtics podria contribuir al desenrotllament i propagació de la resistència als antimicrobians que actualment constitueix un greu problema a nivell mundial. Els resultats d'este treball podrien servir les autoritats de salut pública per a avaluar si els sistemes actuals de control d'antibiòtics en la llet i els productes lactis són adequats o haurien de ser revisats.<br>[EN] Antibiotic residues in milk are a great concern for public health, and they have negative implications for the dairy industry. To guarantee the safety of milk and derivates, Maximum Residues Limits (MRL) for different veterinary drugs in raw milk have been established. However, the transfer of these substances from milk to cheese, has been poorly studied and, therefore, the impact of the use of raw milk containing antibiotics on the cheese-making and the cheese safety is thus far unknown. The aim of this thesis was to evaluate the transfer of the most widely used antibiotics used in dairy goats, from milk to matured and fresh cheese, as well as their effect on the cheese-making process and the quality characteristics of the cheeses during ripening. To this end, antibiotic-free milk was spiked individually with seven veterinary drugs (amoxicillin, benzylpenicillin, cloxacillin, erythromycin, ciprofloxacin, enrofloxacin and oxytetracycline) and used to make mature Tronchón cheeses, which were analyzed at different ripening times (0, 30, and 60 days) to determine antibiotic residues, pH, chemical composition, proteolytic and lipolytic activities, color, and textural properties. The cheese-making process was unaffected by the presence of most antibiotics in milk. Only erythromycin and oxytetracycline significantly increased the time required for cheese production. Regarding cheese characteristics, the few differences found were related to the free fatty acid concentration, color and textural properties, which remained mostly undetected by the sensory analysis panelists. However, variable amounts of antibiotics, ranging from 7.4 to 68 %, were transferred from milk spiked with antibiotics, to cheese. Oxytetracycline and quinolones presented the highest retention rates as well as persistence along maturation, with high concentrations of quinolones (enrofloxacin: 148±12 µg/kg, ciprofloxacin: 253±24 µg/kg) and oxytetracycline residues (20±5.7 µg/kg) in cheeses after 60 days of ripening. In the study of fresh cheeses was evaluated the presence of drug residues in pasteurized fluid milk and fresh cheeses obtained from goat milk containing antibiotics (amoxicillin, benzylpenicillin, cloxacillin, neomycin, erythromycin, ciprofloxacin, enrofloxacin and oxytetracycline) at safety levels (MRLs). The safety margin of these dairy products for consumers was also evaluated. Results showed that high amounts of antibiotics, between 71-100% of the initial concentration in raw milk, remained in pasteurized goat milk and were transferred to cheese to a high extent, with retention percentages ranging from 37.5 to 75%. Regarding the safety margin of goat milk products, calculated taking into account different age groups (children, teenagers and adults), and the published negative effects of such antibiotics on consumer health, results indicate that the minimum safety margin of pasteurized milk was obtained for ciprofloxacin, enrofloxacin and erythromycin in the group of children. Regarding fresh cheese, an elevated safety margin was obtained for all antibiotics and age groups considered. It is important to emphasize that relatively high concentrations of antibiotics could remain in pasteurized fluid goat milk and related products such as fresh cheese and cheeses of a short ripening period. The presence of these antibiotics in dairy products might contribute to the development and spread of antimicrobial resistance, which is considered an important public health concern worldwide. The result of this research could serve the public health authorities to assess if current control systems of antibiotics in milk and dairy products are adequate or have to be revised.<br>Por último, quiero dar las gracias a la educación pública que permite que la economía no sea una barrera para la formación y al “Programa de ayudas a la investigación” (FPI-2014) de la Universitat Politècnica de Valencia, que me concedió la oportunidad de realizar está investigación durante los 4 años de trabajo.<br>Quintanilla Vázquez, PG. (2019). Effect of antibiotics in goat milk on the manufacture and characteristics of cheese [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/125701<br>TESIS

Made available in DSpace on 2014-06-11T19:25:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-03-24Bitstream added on 2014-06-13T18:26:32Z : No. of bitstreams: 1 salvadeo_vm_me_bauru.pdf: 454404 bytes, checksum: f9533c97cafb5b981d239b02a0bf9213 (MD5)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>O produtor de leite de cabra, com o apoio e incentivo de entidades governamentais, privadas e ONGs; agrega tecnologia ao leite garantindo uma melhor distribuição de renda e qualidade de vida, fixando-se cada vez mais no campo. O resfriamento do leite após a ordenha é a melhor medida para retardar a proliferação natural das bactérias e sua temperatura deverá ser reduzida de 36 ºC para 4 ºC no período máximo de 2 horas em cada ordenha. O tempo transcorrido entre a primeira ordenha e seu recebimento na usina de beneficiamento deverá ser, no máximo, de 48 horas. Neste trabalho propõe-se projetar e analisar tanques de resfriamento de leite com capacidades úteis de 320, 500 e 2000 litros em aço inoxidável austenítico AISI 304, utilizando-se do coeficiente global médio (U) e das temperaturas médias de saturação do fluido de refrigeração (X) obtidos em ensaios experimentais. Um objetivo secundário foi verificar a possibilidade da utilização de caixas d'água de polietileno com a mesma capacidade dos tanques, por ser um produto acessível, de baixo custo e que atende as exigências sanitárias, visando obter um produto que possa substituir o aço inoxidável, mas descartou-se esta possibilidade, pois o fundo plano destas caixas dificultaria a retirada do produto e a limpeza. Nos cálculos envolvidos na geometria para a construção dos tanques, utilizou-se da relação entre a altura cilíndrica e o diâmetro que contemplasse respectivamente, o número...<br>The goat milk producer, with support and encouragement of governmental and private agencies as well as NGOs, aggregate technology to milk production ensuring a better distribution of income and life quality for all his family, making it possible the maintenance of the country life. The milk cooling ater the milking process is the best alternative to delay the natural proliferation of bacteria. The milk temperature should be reduced from 36 ºC to 4 ºC in a maximum period of time of two hours for each milking. The elapsed time between the first milking and the milk delivery in the processing plant shall be at most 48 hours. In this work, we propose to design and analyze milk cooling AISI 304 austenitic stainless ateel 320, 500 and 2000 liters tanks, using the mean global coefficient (U) and mean saturation temperatures of the refrigeration fluid (X), obtained experimentally. Besides stainless steel built tanks, accessible low cost polyethylene watertanks, with same dimensions of the steel tanks, attending the necessary sanitary requirements were used, aiming for an alternative product that can replace stainless steel. However, this possibility was rejected, because its flat basis would make it hard the product removal and its cleaning. During the geometric calculations in the manufacturing of the tanks, the relationship betwwen the cylindrical height and the diameter was defined in order to provide the golden ratio and batch square... (Complete abstract click electronic access below)

Amb l'objectiu d'obtenir nous coneixements sobre la base molecular de la lactació en cabres de la raça Murciano-Granadina (MUG), hem dut a terme una anàlisi RNA-Seq de mostres de la glàndula mamària (N=7) obtingudes en tres punts temporals diferents: 78 dies (T1, lactació primerenca), 216 dies (T2, lactació tardana) i 285 dies (T3, període sec) després del part. Aquest experiment ens va permetre identificar 1654 gens expressats diferencialment (DE), les funcions dels quals estaven relacionades principalment amb el metabolisme de les proteïnes, lípids i carbohidrats, homeòstasi del calci, mort cel·lular programada, remodelació tissular i immunitat. A més, vam realitzar un estudi d'associació del genoma complet (GWAS) que va incloure 822 cabres amb registres per set fenotipus lleters mesurats durant la primera lactació amb la finalitat de contribuir a dilucidar l'arquitectura genòmica de la producció i la composició de la llet. Aquest estudi ens va permetre detectar 24 quantitative trait loci (QTL). No obstant això, només tres QTL van mostrar significació estadística a nivell genòmic, és a dir, QTL1 (cromosoma 2, 130,72-131,01 Mb) per al percentatge de lactosa de la llet, QTL6 (cromosoma 6, 78,90-93, 48) Mb) per al percentatge de proteïna i QTL17 (cromosoma 17, 11.20 Mb) per als percentatges de proteïna i matèria seca. Mitjançant l'anàlisi del patró de segregació de polimorfismes d'un sol nucleòtid (SNP) dels genes de les caseïnes en bezoars (ancestre de la cabra domèstica) i cabres domèstiques d'Europa, Àfrica, Pròxim Orient i Extrem Orient, es va determinar que del 36,1% (CSN2) al 55,1% (CSN1S2) dels SNPs són compartits entre bezoar i cabra domèstica. Així mateix, més del 50% dels SNP dels gens de les caseïnes van ser compartits per 2 o més poblacions de cabra doméstica situades en diferents continents, i del 18 al 44% dels SNP van ser compartits per les quatre poblacions domèstiques esmentades anteriorment. Aquests resultats ens permeten concloure que una part important de la diversitat existent en els gens de les caseïnes caprines va emergir abans de la domesticació de les cabres. Un altre objectiu de la Tesi va ser caracteritzar la variació del nombre de còpies (CNV) en una població de 1036 cabres MUG. Mitjançant l'ús del programari PennCNV i QuantiSNP, vam identificar 4617 i 7750 CNV autosòmics, respectivament, que posteriorment van ser acoblats en 486 regions CNV o CNVR. Els gens que mapegen dins de CNV mostren un enriquiment de funcions relacionades amb la transducció olfactiva, els transportadors ABC i el desenvolupament embrionari. Un dels CNVR identificats en el nostre estudi coincideix amb la posició del gen de la proteïna de senyalització agouti (ASIP), que afavoreix la síntesi de feomelanina groga/vermella. En diversos estudis, l'augment del nombre de còpies del gen ASIP va ser associat amb un patró de pigmentació blanc en cabres. No obstant això, al realitzar un experiment de qPCR amb l'objectiu de quantificar el nombre de còpies del gen ASIP en poblacions de cabres amb diferents patrons de pigmentació, vam esbrinar que el CNV de ASIP no solsament segrega en cabres Saanen (blanques), sinó també en cabres MUG (negres/marrons) i cabres Malaguenyes (vermelles/rosses). Aquest resultat indica l'absència d'una relació simple i lineal entre el nombre de còpies del gen ASIP i la di&#320;lució del patró de pigmentació en cabres. Finalment, hem investigat l'arquitectura genòmica de la coloració de la capa en cabres MUG mitjançant la combinació de diferents tècniques experimentals. Aquesta anàlisi ha revelat l'existència d'una estreta associació entre una mutació aminoacídica (c.801C> G, p.Cys267Trp) al gen de receptor de la melanocortina 1 (MC1R) i el color negre/marró de les cabres MUG, la qual cosa implica que l'herència de la pigmentació en aquesta raça és monogènica.<br>Con el objetivo de obtener nuevos conocimientos sobre la base molecular de la lactación en cabras de la raza Murciano-Granadina (MUG), se llevó a cabo un análisis RNA-Seq de muestras de la glándula mamaria (N=7) obtenidas en tres puntos temporales distintos, es decir, 78 días (T1, lactación temprana), 216 días (T2, lactación tardía) y 285 días (T3, período seco) después del parto. Este experimento permitió identificar 1654 genes expresados diferencialmente (DE), cuyas funciones estaban relacionadas principalmente con el metabolismo de las proteínas, lípidos y carbohidratos, homeostasis del calcio, muerte celular programada, remodelación tisular e inmunidad. Con la finalidad de contribuir a dilucidar la arquitectura genómica de la producción y la composición de la leche, realizamos un estudio de asociación del genoma completo (GWAS) que incluyó 822 cabras con registros para siete fenotipos lecheros medidos durante la 1ª lactación. Este estudio permitió detectar 24 quantitative trait loci (QTL). No obstante, sólo tres QTL mostraron significación estadística a nivel genómico, es decir, QTL1 (cromosoma 2, 130,72-131,01 Mb) para el porcentaje de lactosa de la leche, QTL6 (cromosoma 6, 78,90-93,48) Mb) para el porcentaje de proteína y QTL17 (cromosoma 17, 11.20 Mb) para los porcentajes de proteína y materia seca. Mediante el análisis del patrón de segregación de polimorfismos nucleotídicos sencillos (SNP) de los genes de las caseínas en bezoares (ancestro de la cabra doméstica) y cabras domésticas de Europa, África, Cercano Oriente y Lejano Oriente, se determinó que del 36,1% (CSN2) al 55,1% (CSN1S2) de los SNPs son compartidos por el bezoar y la cabra doméstica. Asimismo, más del 50% de los SNP de los genes de las caseínas fueron compartidos por 2 o más poblaciones de cabra doméstica ubicadas en diferentes continentes, y del 18 al 44% de los SNP fueron compartidos por las cuatro poblaciones domésticas mencionadas anteriormente. Estos resultados nos permiten concluir que una parte importante de la diversidad existente en los genes de las caseínas caprinas emergió antes de la domesticación de las cabras. Otro objetivo de la Tesis consistió en caracterizar la variación del número de copias (CNV) en una población de 1036 cabras MUG. Mediante el uso del software PennCNV y QuantiSNP, identificamos 4617 y 7750 CNV autosómicos, respectivamente, que posteriormente fueron ensamblados en 486 regiones CNV o CNVR. Los genes que mapean dentro de CNVR muestran un enriquecimiento de funciones relacionadas con la transducción olfativa, los transportadores ABC y el desarrollo embrionario. Uno de los CNVR identificados en nuestro estudio coincide con la posición del gen de la proteína de señalización agouti (ASIP), que favorece la síntesis de feomelanina amarilla/roja. En diversos estudios, el aumento del número de copias del gen ASIP fue asociado con un patrón de pigmentación blanco en cabras. Sin embargo, al realizar un experimento de qPCR con el objetivo de cuantificar el número de copias del gen ASIP en poblaciones de cabras con diferentes patrones de pigmentación, averiguamos que el CNV del gen ASIP no sólo segrega en cabras Saanen (blancas), sino también en cabras MUG (negras/marrones) y cabras Malagueñas (rojas/rubias). Este resultado indica la ausencia de una relación simple y lineal entre el número de copias del gen ASIP caprino y la dilución del patrón de pigmentación. Finalmente, hemos investigado la arquitectura genómica de la coloración de la capa en cabras MUG mediante la combinación de distintas técnicas experimentales. Este análisis reveló la existencia de una estrecha asociación entre una mutación aminoacídica (c.801C> G, p.Cys267Trp) en el gen del receptor de la melanocortina 1 (MC1R) y el color negro/marrón de las cabras MUG, lo que implica que la herencia de la pigmentación en dicha raza es monogénico.<br>In order to obtain new insights into the molecular basis of lactation in Murciano-Granadina (MUG) goats, we carried out a RNA-Seq analysis of mammary gland samples (N = 7) obtained in three different time points, that is, 78 days (T1, early lactation), 216 days (T2, late lactation) and 285 days (T3, dry period) after parturition. This experiment allowed the identification of 1654 differentially expressed (DE) genes, the functions of which were mainly related to protein, lipid and carbohydrate metabolism, calcium homeostasis, programmed cell death, tissue remodeling and immunity. In order to help elucidate the genomic architecture of milk production and composition, we also carried out a genome-wide association study (GWAS) including 822 goats with records for seven dairy phenotypes measured during the first lactation. This study allowed the detection of 24 quantitative trait loci (QTL). However, only three QTL showed statistical significance at the genome-wide level, that is, QTL1 (chromosome 2, 130.72-131.01 Mb) for the percentage of lactose in milk, QTL6 (chromosome 6, 78.90-93, 48) Mb) for the percentage of protein and QTL17 (chromosome 17, 11.20 Mb) for the percentages of protein and dry matter. By analyzing the segregation patterns of single nucleotide polymorphisms (SNPs) mapping to the casein genes in bezoars (ancestor of the domestic goat) and domestic goats of Europe, Africa, the Near East and the Far East, it was determined that about 36.1% (CSN2) to 55.1% (CSN1S2) of casein SNPs are shared between bezoars and domestic goats. Besides, more than 50% of the SNPs of the casein genes were shared by 2 or more domestic goat populations located on different continents, and 18 to 44% of the SNPs were shared by the four previously mentioned domestic populations. These results allow us to conclude that an important part of the diversity existing in the caprine casein genes emerged before the domestication of goats. Another objective of the Thesis consisted of characterizing copy number variation (CNV) in a population of 1036 MUG goats. Using the PennCNV and QuantiSNP software, we identified 4617 and 7750 autosomal CNVs, respectively, which were subsequently assembled into 486 CNV regions (CNVR). Genes located within CNV show an enrichment of functions related to olfactory transduction, ABC transporters and embryonic development. Interestingly, one of the CNVR identified in our study coincides with the position of the agouti signaling protein (ASIP) gene, which favors the synthesis of yellow/red pheomelanin. In several studies, increased copy number of the ASIP gene was associated with a white pigmentation in goats. However, when conducting a qPCR experiment with the objective of quantifying the number of copies of the ASIP gene in goat populations with different coat colors, we found that the ASIP CNV not only segregates in Saanen (white) goats, but also in MUG (black/brown) and Malagueñas goats (brown/blond). This result indicates the absence of a simple and linear relationship between the number of copies of the goat ASIP gene and the dilution of pigmentation. Finally, we have investigated the genomic architecture of coat color in MUG goats by combining different experimental techniques. This analysis revealed the existence of a close association between a missense mutation (c.801C>G, p.Cys267Trp) in the melanocortin receptor 1 (MC1R) gene and the black/brown color of MUG goats, which implies that the inheritance of pigmentation in this breed is monogenic.<br>Universitat Autònoma de Barcelona. Programa de Doctorat en Producció Animal

This study has compared the effect of milk pricing systems on the selection goals of dairy producers in two provinces of Canada, British Columbia (BC), and Quebec. These provinces were chosen for comparison as BC produces milk largely for a fluid market, while Quebec produces milk for a manufacturing market. Within BC, due to a higher utilization and higher milk price, the value/kg of skim on Vancouver Island was higher than that of the Vancouver Lower Mainland over the study period 1963-1982. Between the two provinces, the value/kg of skim in BC was found to be consistently higher than in Quebec over the 20 year period, while the value of fat was higher in Quebec than BC. In BC in 1980, the value of a kilogram of skim was approximately $0.30, whereas its value in Quebec was only $0.20. During the 1960s in BC, the value of skim represented one half the value of milk, and in 1982 it comprised two thirds of the value of milk, as compared to Quebec, where fat represented 43% of the value of milk. Net economic values were calculated by subtracting the dollar cost of production associated with the components of milk (carrier, fat and protein), from the gross value/kg of skim and fat. These values showed that the value/kg of protein was negative and decreasing in both BC and Quebec. The economic value/kg of butterfat has been consistently positive and increasing over the study period in BC and Quebec to $3.27 and $3.34/kg respectively in 1982. The relative economic values of carrier, fat and protein in BC and Quebec in 1982 were 0.08:1.00:-0.10 and 0.06:1.00:-0.12 respectively, which puts moderate selection on carrier and fat, and negative selection on protein. Selection index weights for carrier, fat and protein revealed that the BC dairy industry has always applied positive selection to the carrier and fat portion, and negative selection to the protein portion of milk. In 1982 the selection weights were 0.087:1.253:-1.189. The Quebec index has shown more fluctuation that BC, with less selection against solids compared to BC; (0.050:1.280:-0.657). Theoretical genetic goals of the BC dairy industry have been consistent at approximately 3.0% butterfat, 2.0% protein and 95.0% carrier. The genetic goals in Quebec have undergone wide fluctuations, but generally have signalled the dairy producer to increase both butterfat and protein. The goals of the two industries are now very similar, with the exception that Quebec continues to place higher value on solids than BC.<br>Land and Food Systems, Faculty of<br>Graduate

碩士<br>國立中興大學<br>畜牧學系<br>86<br>The purpose of this study was conducted to examine cow milk or reconstituted milk components in goat milk by electrophoresis method. Based on the varied electrophoretic mobilities of milk proteins, (s1-casein demonstrated a higher electrophoretic mobility than (s2-casein. Moreover, since (s1-caseinis is absent or account for a minor content in goat milk, consequently the characteristics of goat (s1-casein make it easy to detect adulteration of goat milk with cow milk. To precipitate more casein contents, milk proteins were separated by the isoelectric point of casein at pH 4.6. The casein concentrations in Saanen、 Toggenberg、Nubian、Alpine and Lamancha goats were: 25.46±1.98 mg/ml、22.08±1.29mg/ml、22.68±1.75mg/ml、24.21±1.15mg/ml 、29.13±1.87mg/ml respectively。 Goat or bovine caseins in the agarose gels displayed three major bands of A、B and C. Fresh goat milk、reconstituted goat milk(Bate(s or Sentosa)、 fresh cow milk and reconstituted cow milk also dramatically varied in band proportions after densitometerically scanned, as following: fresh goat milk, A band 11.98±0.59%、B band 41.41±0.53%、C band 46.62±0.63%；reconstituted goat milk(Bate( s ), A band 10.38±0.52%、B band 32.25±0.59%、C band 57.37±0.77%；reconstituted goat milk(Sentosa), A band 9.99±0.68% band 36.54±0.79%、C band 53.45±0.47%；fresh cow milk, A band 54.77±0.64%、B band 8.90±0.42%、C band 36.33±0.38%；reconstituted cow milk, A band 51.32±0.74%、B band 9.84±0.43%、C band 38.85±0.66%. With the adulteration of reconstituted or fresh cow milk, the relative area proportions of A and B bands in fresh goat milk showed a dramatically change. However, when added with reconstituted goat milk, the area proportion of A and B bands in fresh goat milk were not altered. Since the area percentage of A band in goat milk was closely proportional to the content of fresh or reconstituted cow milk in casein electropherogram, regression analysis between the adulterated cow milk content and area percentage of A band in fresh goat milk revealed a high correlation coefficient( r2=0.98). The results of this study can be employed to detect the adulteration of fresh or reconstituted cow milk in fresh goat milk.

碩士<br>國立屏東科技大學<br>畜產系<br>94<br>Ionic calcium（iCa） concentration is an important factor affecting casein micelles stability in goat’s milk. Several factors affect the equilibrium of calcium in milk, such as pH, milk compositions and structure of casein complex. The purpose of this study was to investigate the variations in compositions and physicochemical properties of goat’s milk at different stages of lactation, and the relationships among ionic calcium concentration, milk composition and physicochemical properties. Milk gross compositions of individual goats were taken for measuring fat, protein, lactose, solids-not-fat and somatic cell counts. The physicochemical properties of milk include pH, titratable acidity (TA), ethanol stability (EtOH%), total calcium concentration (tCa)and ionic calcium concentration. Experiment 1 was to investigate the effect of calcium chloride addition and pH adjustments on the ionic calcium concentration and ethanol stability in bulk goat’s milk. The concentrations of added calcium chloride concentration in goat’s milk were 0.00, 0.25, 0.50, 0.75, 1.00, 1.50, 2.00, 5.00 and 10.00 mM, respectively. The measurements of iCa concentration, pH and EtOH% of adjusted goat’s milk were carried out. Results showed that increasing amount of calcium addition in goat’s milk increased iCa concentration, but decreased pH and EtOH%. In this study, the addition of 0.50 mM calcium increased the iCa concentration from 3.00 mM to 3.29 mM, and decreased the EtOH% from 48% to 44%. The ionic calcium concentration of bulk goat’s milk increased as the pH decreased. Decreasing the pH of bulk goat’s milk from 6.68 to 6.60, the iCa concentration increased from 3.02 mM to 3.27 mM, but the EtOH% decreased from 48% to 43%. Experiment 2 was to investigate the relationships between EtOH% and iCa in milk samples taken from 12 individual Saanen goats. After labor, samples of individual goat’s milk were taken everyday at first week, then once a week for the rest of lactation period. According to lactation stages, milk samples were presented as colostrums (less than day 7), early-lactation (day 8-100), mid-lactation (day 101-200) and late-lactation (later than day 201) milks, respectively. Results showed that the fat, protein, lactose and solids-not-fat (SNF) contents in goat’s colostrums were significant higher than these in early-lactation, mid-lactation and late-lactation milks (P＜0.05). Analysing the relationships of milk compositions and iCa concentration showed that iCa concentration of individual goat’s milk was positively related to milk fat (P＜0.001) and protein (P＜0.01), and negatively related to lactose (P＜0.01). The pH value of colostrums was significant lower than milks at other stages in lactation (P＜0.05), but TA of colostrums was higher (P＜0.05). The EtOH% of mid-lactation milk was the highest in milk at all stages of lactation, and ionic calcium concentration in mid-lactation milk was the lowest. The tCa concentration of colostrum was significant higher than at other stages of lactation. The tCa concentration of late-lactation milk was significant higher than at early-lactation and at mid-lactation milks. The ionic calcium concentration of colostrum was significant higher than in individual goat’s milk and bulk goat’s milk. Both EtOH% and pH of colostrum were significant lower than in individual goat’s milk and bulk goat’s milk. There was a significant negative relationship between ionic calcium concentration and ethanol stability (r= -0.7740, P＜0.001). The ranges of the EtOH% and iCa concentration of 12 goats over lactation period were from 20 to 69 % and from 1.40 mM to 3.99 mM, respectively. Both EtOH% and iCa concentration showed normal distribution when analysing data of both EtOH% and iCa concentration at 5% and 0.20 mM interval, respectively. There were variations in iCa concentration and EtOH% of individual goat’s milks from different stages in lactation. The EtOH% of milk decreased in months as the iCa concentration increased. To sum up, the goat’s milk of mid-lactation had the higher milk quality during lactation period.

Research Doctorate - Doctor of Philosophy (PhD)<br>Goat's milk and goat's milk products are widely consumed in developing countries, and are attractive to many consumers in developed countries due to their therapeutic and nutritional value. Although an increasing global demand exists, the variety of commercially available goat's milk products is currently limited. Goat's milk itself may be a suitable vehicle for delivering probiotics to humans, and the addition of probiotics to goat's milk may further enhance its health promoting value. This thesis examines the feasibility of using the novel probiotic Propionibacterium jensenii 702 in co-culture with established probiotic organisms (lactobacilli and bifidobacteria) in the manufacture of goat's milk products such as fermented milk, yogurt, ice cream and spray dried powder. To provide beneficial health effects probiotic bacteria must survive passage through the gastrointestinal tract, then adhere to and colonise the gut epithelium. As these functional properties can be influenced by the food carriers used in probiotic delivery, a series of in vitro studies were performed to investigate the effect of goat's milk carrier foods on these functional aspects of probiotic efficacy. The viability of the probiotics during product shelf life, and the physico-chemical characteristics and sensory attributes of these products, were also analysed in order to assess both their general quality and appeal. The first of the studies presented involved the examination of different mono-culture and co-culture combinations of P. jensenii 702 in fermented goat's milk with respect to viability during storage, physico-chemical and sensory attributes of the milk, and in vitro gastrointestinal tolerance and adhesion ability. Co-cultivation of P. jensenii 702 with L. acidophilus LA-5 and B. animalis subsp. lactis BB-12 in goat's milk was not found to impact adversely on either the physico-chemical properties or sensory characteristics of the fermented milk preparations, or the functional properties of these bacteria. Thus it was found that combining P. jensenii 702 with lactobacilli and bifidobacteria could be effectively utilised in the development of probiotic goat's milk products. Based on these findings, a triple co-culture of these three organisms was utilised in all subsequent studies. In the second study, plain and stirred fruit yogurts were developed. P. jensenii 702 demonstrated high viability (108cfu/g) in all types of yogurt throughout storage, while the viability of the bifidobacteria also remained above the minimum recommended level (106 cfu/g). However, the results indicated that yogurt starter culture bacteria may have had an adverse effect on L. acidophilus LA-5 viability during the shelf life of the products, resulting in low viable counts in both types of yogurts (<105 cfu/g). In general the physico-chemical properties of the yogurts were within acceptable ranges and sensory tests revealed that the addition of fruit juice improved consumer acceptability of the yogurt. The third study involved development of a chocolate flavoured probiotic ice cream using goat's milk. In addition to the performance of P. jensenii 702, the effect of packaging materials on both probiotic viability, and the physico-chemical and sensory properties of the product were also evaluated. Regardless of packaging type (glass, polyethylene or polypropylene) all three probiotics were able to maintain high viability (107-108 cfu/g) in the ice cream during 52 weeks of storage at -20°C. While no significant effect on the sensory properties of the ice cream could be associated with the packaging materials, product stored for 12 weeks was more highly ranked for all sensory attributes than that stored for one week. The relative influence of different food matrices on the gastrointestinal tolerance and adhesion of probiotics was examined in vitro using goat's milk ice cream, plain and 10% stirred fruit yogurts. In relation to the different food types, significant variation in the viability of all three probiotics was observed when exposed to simulated gastro-intestinal conditions of either low pH (2.0) or 0.3% bile. In general, ice cream was found to improve the acid and bile tolerance of the probiotics compared to plain and stirred fruit yogurts. In contrast, the fruit yogurt appeared to be the most favourable carrier in terms of in vitro adhesion of the probiotics to human Caco-2 intestinal cells, although a substantial number of viable bacteria (105-106 cfu/g) were found to be adherent in all cases. The effects of micro-encapsulation and subsequent storage on the viability of the three probiotics was examined after spray drying the triple combination in reconstituted goat's milk. Although spray drying resulted in an initial reduction in the number of viable cells, the viability of all three probiotics remained unaffected (~106 cfu/g) under refrigerated storage for 24 weeks. Rehydration of spray dried probiotics in coffee and black tea at 85°C lowered viable cell numbers, however, both P. jensenii 702 and L. acidophilus LA-5 retained satisfactory viability (~106 cfu/g) even after rehydration at this temperature. This thesis provides evidence to suggest that the novel probiotic P. jensenii 702 may be successfully utilised in probiotic co-culture for the manufacturing of functional goat's milk products such as ice cream and yogurts. The findings also reveal the importance of careful selection of both the species to be used in co-cultured probiotic preparations, and a suitable carrier food matrix, in order to assure maximum benefit to consumers.

碩士<br>東海大學<br>畜產學系<br>89<br>The study was conducted to inhibit the growth of psychrotrophs by injection of carbon dioxide to keep the best quality of raw goat’s milk. The study had three parts─Exp.Ⅰ: Effect of carbon dioxide injection on raw goat’s milk quality; Exp.Ⅱ: Effect of carbon dioxide on P. fluorescens inoculated raw goat’s milk quality; Exp.Ⅲ: Effect of carbon dioxide treated milk on sensory evaluation of pasteurized milk and yogurt. Carbon dioxide treatments in our study were controlled by pH value, and raw goat’s milk were treated until pH 6.5 and pH 6.4. Results showed carbon dioxide treatment had significantly effect on inhibiting psychrotrophs (p < 0.05), but had no significant effect on TPC and LABC (p < 0.05). Because of carbon dioxide dissolving into raw goat’s milk, pH value of two carbon dioxide treatments decreased. Viscosity of both treatments increased because the acidity influenced structure of casein micelles. But at 10th day, because of spoilage and whey off of raw goat’s milk, viscosity of control were significantly lower than carbon dioxide treatments (p < 0.05). However, carbon dioxide treatment increased the ethanol sensitivity of raw goat’s milk, but not influence the heat denatured precipitate percentage of raw goat’s milk. So, ethanol test, which was used by dairy plant, was not suitable in carbon dioxide treated milk, but heat denatured precipitate at 80℃ 10 min could replaced ethanol test. Raw goat’s milk with high quality treated with carbon dioxide maintained the best quality of raw goat’s milk, and for the raw goat’s milk with low quality, although carbon dioxide inhibited the growth of psychrotrophs (p < 0.05), too, psychrotrophs grew and produced lots of protease, meanwhile injection of carbon dioxide increased the activity of enzyme, and increased the proteolysis (p < 0.05). No differences between carbon dioxide treatments and control when fresh milk and yogurt were processed by raw goat’s milk, implied that dairy plant could use carbon dioxide to keep the quality of raw goat’s milk.

碩士<br>長榮大學<br>經營管理研究所<br>93<br>The domestic market of goat milk has been up and down through the integration leading by the Council of Agriculture, Executive Yuan during the past ten years. The market is seriously wounded after being through the events of a foot-and-mouth disease, fake goat milk, and the participation of WTO in 2000. In order to inspire the market, the GGM, which is an emblem of representing goat milk product, is created to re-build the confidence of customers. Bill Gates declared: “The winner is the one who controls the channel”. The goat milk market is a unique channel which focuses mainly on the customers. The market is highly related to the customers and services regarding the commerce from the business spreading to home delivery. Therefore, we can infer a new slogan from Mr. Gates’ quotation, “The one who controls the channel is the overlord, and the winner is the one who obtains the trust of customers”. It reflects the spirit of customer-oriented business. To understand the current status of goat milk market, the course of change and development, customer behavior, consuming decision, and the change of channel, this research synthesizes a market survey and result analysis to achieve the goal. Moreover, a case study is used to analyze and prove the key factors to be successful for the goat milk business. The research further studies the characteristics of customers who enjoy the goat milk products. A fixed consuming behavior from most of customers is concluded from the analyses of survey results. The analyses illustrate that most of the consuming behavior focused on several main choices and their buying decision did not have noticeable differences. We concluded the consuming consistence of customers who enjoy goat milk products. The main channel of the goat milk market is to provide the home delivery to their customers over the decades. Several companies have tried different ways to challenge the channel; they failed. However, the goat milk proprietors will keep their efforts to challenge the business. The key point to success is to maintain the knowledge of market trend and consumer behavior. In summary, the outcome of this research is to suggest a proposal as a reference when developing the goat milk market and making the product orientation policy.

Метою роботи було провести порівняльне дослідження жирнокислотного складу молока коров’ячого, коз’ячого та овечого, а також дослідити жирнокислотний склад молочного жиру коров’ячого молока при його скисанні впродовж 72 годин. На основі проведених газохроматографічних досліджень встановлено у жирнокислотному профілі молочного жиру коров’ячого молока впродож 72 годин скисання відбуваються кількісні і якісні зміни, які обумовлені діяльністю мікрофлори при молочнокислому бродінні. Встановлено, що при скисанні молока коров’ячого впродовж 72 годин істотно коливається співвідношення між вмістом насичених і ненасичених жирних кислот, яке через 24 години скисання становило 1,97 : 1, через 48 годин - 1,81 : 1, а через 72 години 1,77 : 1. Сумарний відносний вміст поліненасичених жирних кислот у молочному жирі коров’ячого молока при скисанні через 24 години становив – 5,41%, через 48 годин - 5,76%, а через 72 години – 6,25%. Така динаміка свідчить про достовірне зростання кількості поліненасичених жирних кислот у молочному жирі коров’ячого молока при його скисанні впродовж 72 годин. Показано зміни вмісту жирних кислот родин омега-3 у молочному жирі коров’ячого молока при скисанні, а саме: через 24 години сумарний вміст омега-3 поліненнасичених жирних кислот складав 0,46%, через 48 годин - 0,43%, а через 72 години лише 0,39% від загального відносного вміст усіх жирних кислот.<br>The aim of the study was to conduct a comparative study of the fatty acid composition of cow's, goat's and sheep's milk, as well as to study the fatty acid composition of cow's milk milk fat during its fermentation for 72 hours. Based on the conducted gas chromatographic studies, quantitative and qualitative changes occur in the fatty acid profile of cow's milk fat during 72 hours of fermentation, which are due to the activity of the microflora during lactic acid fermentation. It was found that when fermenting cow's milk for 72 hours significantly varies the ratio between the content of saturated and unsaturated fatty acids, which after 24 hours of fermentation was 1.97: 1, after 48 hours - 1.81: 1, and after 72 hours 1 , 77: 1. The total relative content of polyunsaturated fatty acids in the milk fat of cow's milk during fermentation after 24 hours was - 5.41%, after 48 hours - 5.76%, and after 72 hours - 6.25%. This trend indicates a significant increase in the amount of polyunsaturated fatty acids in the milk fat of cow's milk when fermented for 72 hours. The changes in the content of fatty acids of the omega-3 families in the milk fat of cow's milk during fermentation are shown, namely: after 24 hours the total content of omega-3 polyunsaturated fatty acids was 0.46%, after 48 hours - 0.43%, and after 72 hours only 0.39% of the total relative content of all fatty acids.<br>Реферат Вступ 1 РОЗДІЛ 1. Огляд літератури. 1.1 Фактори, що впливають на склад і властивості молока 1.2 Фактори, що впливають на жирність молока 17 1.3. Показники ідентифікації сирого молока різних видів сільськогосподарських тварин 1.4 Мікробіологічні і санітарно-гігієнічні показники молока 1.5 Вплив жирнокислотного складу молока на його біологічну цінність і виробництво молочних продуктів 1.6. Походження молочних жирних кислот 2 Розділ 2. Матеріали і методи досліджень 2.1 Схема і дизайн дослідження 2.2 Методика визначення жирнокислотного складу молока 3.1. Розділ 2. Результати дослідження та їх обговорення 3.1 Жирнокислотний профіль козячого молока 3.2. Жирнокислотний профіль коров’ячого молока 3.3 Середні значення відносного вмісту жирних кислот у коров’ячому молоці 3.4 Вплив процесу скисання коров’ячого молока на його жирнокислотний профіль 3.4.1. Відносний вміст жирних кислот у молочному жирі коров’ячого молока через 24 години ферментації 3.4.2. Відносний вміст жирних кислот у молочному жирі коров’ячого молока через 48 години ферментації 3.4.3. Відносний вміст жирних кислот у молочному жирі коров’ячого молока через 72 години ферментації 3.5 Узагальнення отриманих результатів Висновки і пропозиції виробництву 4 Розділ 4. Охорона праці та безпека в надзвичайних ситуаціях 4.1 Захист сировини та готової продукції на об’єктах харчової промисловості Бібліографія Додатки

碩士<br>國立中興大學<br>畜產學系<br>88<br>The purposes of this study were conducted to investigate the variation of milk somatic cell counts (SCC), electrical conductivities (EC), milk serum lactate dehydrogenase activities and milk production in goats for monitoring the health of udder and the quality of goat milk. Individual half udder samples of morning and evening milking were taken from twenty does weekly. In addition, milk production of individual doe was recorded weekly, and the bacterial isolation of each half udder milk sample was tested monthly. The result showed that the milk production of morning milking in individual doe was significantly higher than those in evening milking, the electrical condutivites of morning milking samples were higher than those in the evening milking samples, but there were no significant difference can be seen, while the somatic cell counts and lactate dehydrogenase activities of evening milking samples were significantly higher than those in the morning milking samples (P<0.05 ). The correlation coefficients of somatic cell counts, lactate dehydrogenase activities and electrical conductivities with milk production were —0.42, -0.52 and —0.12 respectively, while the correlation coefficients of somatic cell counts with lactate dehydrogenase activities, somatic cell counts with electrical conductivites, and lactate dehydrogenase activities with electrical conductivities were 0.65, 0.15 and 0.21 respectively. The correlation coefficients of LDH1 and LDH2 with SCC were —0.57 and —0.20 respectively, while the coefficients of LDH3, LDH4 and LDH5 with SCC were 0.66, 0.37 and 0.28 respectively. In does, the LDH3, LDH4 and LDH5 activities of infected half udder were significantly higher than those in the normal half udder (p<0.01), while the LDH1 activities in half udder were significantly lower than those in the normal half udder (p<0.01). The result of this study indicated that the analysis of somatic cell counts and lactate dehydrogenase activities can be used as an indicator for monitoring the subclinical mastitis of dairy goat.

The aim of this study was to develop and examine the validity of using a phenotype scoring system (PTS), a new concept, in evaluating milk yield and constituents in different goat genotypes (Indigenous, British Alpines, Saanen and Toggenburg) raised in small scale production systems. Strategic decisions of small scale African farmers are mostly based on visual appraisal or body condition scoring (BCS) of their animals. BCS has been highly recommended as a means to evaluate both the energy and the health status of animals, especially in beef farming, but this method has been criticized for being too simple and too subjective because its evaluation is often done too late after the damage has already happened. Phenotype scoring (an approach which includes breed, udder size and BCS of the animal) is presented in this study as a better tool to evaluate milk yield in different goat genotypes raised under free range conditions. This has also been a good opportunity firstly to indicate which, among the three dairy breeds of goat under discussion, can adapt best to the African small scale farming system; secondly to review the relevance of some blood metabolites in characterizing milk production in different goat breeds and thirdly to study the milking capacity of the indigenous compared to the dairy goats raised under small scale production systems in South Africa. Thirty-two goats (8 Indigenous, 8 British Alpines, 8 Saanen and 8 Toggenburg) were raised in a free range system at the ARC-Irene experimental farm close to Pretoria. The experiment was a completely randomized experimental design with eight replicates per treatment group. Blood samples were collected by jugular venipuncture into 10 ml heparinised tubes in the morning before feeding on a weekly basis over a period of two months. Blood plasma was immediately aspirated after centrifugation (3000G), kept on ice and brought to the laboratory for the analysis of glucose, cholesterol, urea nitrogen (BUN) and free fatty acid (FFA) concentrations. Immediately after, all does were entirely milked (followed by 1ml oxytocin IM injection and the kids taken away for a period of four hours) before a second milking session took place to measure the daily milk yield of the does. Milk samples were analyzed for lactose, milk proteins, milk fat, milk urea-nitrogen (MUN) and milk somatic cell count (SCC). In addition body condition score (BCS), age and data related to the goat genotype (breed, udder characteristics) were recorded. Results confirmed that milk yield from dairy goats was higher (p<0.001) than the milk yield of indigenous goats during the entire period of study. Milk lactose values recorded in this study (between 3.9 and 4.9%) were the most stable constituent in goat’s milk. Milk protein concentration (between 3.1 and 4.5%) was significantly higher in the indigenous than in dairy breeds, especially in week one and from week four onwards. Milk fat values (between 3.3 and 7.7%) displayed a decline in all breeds; but as from week three, the fat in milk of indigenous does increased and from week five onwards, it remained significantly higher (p<0.001) compared to that of dairy breeds. In conclusion, the superiority of dairy breeds in milk yield was proven while the quality of indigenous goat milk was recognized. Studies on the characterization of milk production in different breeds revealed that the Toggenburg was superior to the other breeds, followed by the British Alpines and the Saanen; but the British Alpines showed a better adaptability to the environment followed by the Toggenburg and the Saanen. The latter could not produce milk without feed supplementation and lost most body condition as compared to the other breeds. Statistical analyses indicated that breed influenced milk yield, milk fat and the protein content of milk (especially in the Saanen and Toggenburg goats). BCS influenced fat content, lactose, milk proteins, MUN and SCC and also milk yield. Udder size influenced milk proteins and milk yield while udder attachment was associated with milk yield only. These results show that PTS, because it takes into account BCS, breed and udder size, is a better tool for predicting milk yield of goats herded in small scale farming systems. Africans interested in dairy goat farming should adopt PTS as a means to evaluate milk yield especially since milk is sold per volume and not by quality in Africa. Finally, milk from the indigenous goats is superior in terms of lactose, fat and protein content. The latter quality attributes can be used as selection criteria since the milk industry pays premiums for the fat and protein content of milk.<br>Thesis (PhD)--University of Pretoria, 2012.<br>Animal and Wildlife Sciences<br>unrestricted