Dissertations / Theses: 'Chicken broiler'

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Molepo, Lephai Sarah. "Effect of moringa seed meal supplementation on productivity and carcass characteristics of ross 308 broiler chickens." Thesis, University of Limpopo, Turfloop Campus, 2014. http://hdl.handle.net/10386/1340.

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Thesis (MSc. Agriculture (Animal Production)) -- University of Limpopo, 2014 Two experiments were conducted to determine the effect of moringa seed meal supplementation on productivity and carcass characteristics of Ross 308 broiler chickens. The first experiment determined the effect of moringa seed meal supplementation on productivity of Ross 308 broiler chickens aged one to 21 days. Two hundred and fifty unsexed day-old Ross 308 broiler chicks were randomly allocated to five dietary treatments, replicated five times, and each replication having 10 chickens. A completely randomized design was used. The chickens were fed on a grower diet supplemented with 0 (M0), 5 (M5), 10 (M10), 15 (M15) and 20 (M20) g of moringa seed meal/bird/day. Moringa seed meal supplementation had no effect (P>0.05) on feed intake, metabolisable energy intake, nitrogen retention, feed conversion ratio and live weight of unsexed Ross 308 broiler chickens. Moringa seed meal supplementation improved (P<0.05) growth rates of unsexed Ross 308 broiler chickens aged one to 21 days. A moringa seed meal supplementation level of 13.3 g/kg DM feed optimized growth rate of Ross 308 broiler chickens aged one to 21 days. The second experiment determined the effect of moringa seed meal supplementation on productivity and carcass characteristics of female Ross 308 broiler chickens aged 22 to 42 days. The chickens weighing 558 ± 10 g/bird were randomly allocated to five treatments with five replications having 10 birds. The chickens, aged 21 days, were allocated to the treatments in a completely randomized design. The chickens were fed on a grower diet supplemented with 0 (FM0), 5 (FM5), 10 (FM10), 15 (FM15) and 20 (FM20) g of moringa seed meal per kg DM. Moringa seed meal supplementation had no effect (P>0.05) on feed intake, growth rate, feed conversion ratio, live weight, metabolisable energy intake, carcass weight, breast meat weight, abdominal fat pad weight, liver weight, heart weight, thigh weight, meat flavour, juiciness and tenderness of female Ross 308 broiler chickens. However, moringa seed meal supplementation improved (P<0.05) nitrogen retention and gizzard weights of female Ross 308 broiler chickens. vi It was concluded that moringa seed meal supplementation improved growth rate of unsexed Ross 308 broiler chickens aged one to 21 days. Similarly, moringa seed meal supplementation increased nitrogen retention and gizzard weights of female Ross 308 broiler chickens aged 22 to 42 days.

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Nagaraj, Manonmani. "Evaluation of nutrition and management factors in the etiology of pododermatitis in broiler chickens." Auburn, Ala., 2006. http://repo.lib.auburn.edu/Send%206-15-07/NAGARAJ_MANONMANI_39.pdf.

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Viñado, Martínez Alberto. "Use of soybean lecithin in broiler chicken diets." Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/667795.

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La adición de grasas es una práctica habitual en la fabricación de piensos para avicultura, ya que son fuente de energía y ácidos grasos esenciales. La disponibilidad de ingredientes con alto contenido energético se puede ver reducida a causa del aumento de población mundial y la utilización de aceites vegetales para la producción de biodiesel. Por ello, la lecitina de soja (L), un coproducto del refinado del aceite de soja (S), puede ser una fuente de energía alternativa, ya que presenta un alto contenido en fosfolípidos, triacilgliceroles, ácidos grasos libres (AGL), fósforo, colina y compuestos antioxidantes. Por todo ello, el objetivo de la tesis fue estudiar el uso potencial de L como fuente de energía para piensos de pollos de carne. Para ello, se realizaron varios ensayos con el objetivo de estudiar el uso de L como fuente de energía en la alimentación de pollos y evaluar su influencia sobre el rendimiento productivo, digestibilidad de los ácidos grasos (AG), utilización de la energía y perfil de AG de la grasa abdominal. Una dieta base fue suplementada al 3% con S o aceite ácido (A), que fueron sustituidos por niveles crecientes (1%, 2% y 3%) de L (cruda o con alto contenido en AGL en el Capítulo Tres y Cuatro, respectivamente). En relación con la sustitución de S por L, aunque durante la fase de iniciación no se observaron efectos sobre el rendimiento productivo, los balances de digestibilidad demostraron que la incorporación de L disminuyó la digestibilidad de los AG y el contenido en energía metabolizable aparente del pienso. Sin embargo, en la fase de crecimiento-acabado, la sustitución parcial de L (hasta un 2%), no dio lugar a modificaciones en el rendimiento productivo ni la utilización de la energía y de AG. Respecto a la sustitución de A por L, tanto en fase de iniciación como en la de crecimiento-acabado, se observó que la combinación de ambos coproductos dio lugar a una mayor utilización de la energía y los nutrientes. Finalmente, el perfil de AG de la grasa abdominal estaba directamente relacionado con el perfil de AG del pienso, y no se observaron modificaciones importantes al sustituir S por L. En el último ensayo (Capítulo Cinco) se desarrolló una prueba de campo bajo condiciones experimentales con el objetivo de estudiar, diferentes niveles de inclusión de L en sustitución de S en dietas de pollos de crecimiento y de acabado, y su efecto sobre el rendimiento productivo. Además, se estudió el efecto sobre la digestibilidad ileal de los AG, el perfil de AG de la grasa abdominal y la salud intestinal. La sustitución total del S (2% de inclusión) por L, en dietas que también contenían aceite de palma y A (3,25% y 4,5% de grasas añadidas en crecimiento y acabado, respectivamente) no modificó el rendimiento productivo, la digestibilidad ileal de los AG totales y la morfología yeyunal. Por otro lado, se observó una reducción de la digestibilidad ileal de los AG poliinsaturados y un incremento en los recuentos de Lactobacillus spp. en yeyuno; aunque, sin consecuencias significativas sobre los parámetros productivos. El perfil de AG de la grasa abdominal reflejó el perfil de AG de las grasas, sin observarse importantes modificaciones. Como conclusiones podemos decir que L es una fuente de energía alternativa adecuada para pollos de carne en crecimiento y acabado, pudiendo sustituir S hasta un 2% sin alterar el rendimiento productivo, la utilización de energía y los AG. Además, la combinación L y A es una alternativa interesante para pollos adultos gracias a la existencia de interacciones positivas sobre la utilización de la energía y los AG. Fat addition is a common practice in feed manufacturing in order to increase the energetic density of diets and provide essential nutrients to livestock animals. The availability of conventional energetic ingredients for broiler chicken diets may be compromised by a constant growing world-wide population and the current tendency to use vegetable oils for biodiesel production. In this context, soybean lecithin (L), as a co-product obtained during soybean oil (S) refining process, may represent an economical and alternative energy source due to its high content in phospholipids, triacylglycerols, free fatty acids (FFA), phosphorus, choline and antioxidant compounds. Therefore, the global aim of the present thesis was to investigate the potential use of L, as energy source for broiler chicken diets. Several trials were performed with the aim to evaluate the inclusion of L as energy source in broiler feeding and study its influence on performance, energy utilization, fatty acid (FA) digestibility and the FA profile of the abdominal fat pad. A basal diet was supplemented at 3% with either S or acid oil (A) and increasing amounts of L (crude and high in FFA for Chapter Three and Four, respectively) were included in replacement (1%, 2% and 3%). In relation to S replacement, despite no effects were observed on performance parameters, results from the digestibility balances indicated that S replacement by L, in starter broiler chickens, lowered FA digestibility and the apparent metabolizable energy content of the diets. However, in grower-finisher broiler chickens, partial replacements up to a 2%, did not modify performance, and the utilization of energy and total FA. Regarding the replacement of A by L, in starter and grower-finisher broiler chicken diets, it was observed that blending both co-products have resulted in improvements on energy and nutrient utilizations. Finally, the FA profile of the adipose tissue was a clear reflect of the FA composition of the added fats, and S replacement by L produced slight changes on the FA profile of the abdominal fat pad. The last experiment (Chapter Five) consisted in a field trial under experimental conditions with the main objective to study, in grower and finisher broiler chicken diets, different levels of L inclusion in replacement of S and its effects on growth performance. In addition, ileal absorption of FA, FA profile of the abdominal fat pad and gut health markers were assessed. Soybean oil total replacement by L (2% of inclusion), in diets that also contained palm and A (3.25% and 4.5% of total added fats for grower and finisher diets, respectively), did not modify performance parameters, total FA ileal digestibility and jejunal morphology. On the other hand, a reduction on the digestibility of the polyunsaturated FA and an increase on Lactobacillus spp. counts at the jejunum were linked to total replacement; however, with no significant consequences on growth efficiency. Slight modifications were observed on the saturation degree of the abdominal fat pad, associated to the FA profile of the different added fats. Taking all the results into account, it was evidenced that L is a suitable energetic ingredient for grower and finisher broiler chicken diets due to it was observed that S partial replacements up to a 2% by L do not alter growth performance and the utilization of energy and FA. Besides, the blending of L and A results an interesting option, for adult broiler diets, due the existence of positive interactions on energy and FA utilization.

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Rodríguez, Sánchez Raquel. "Use of acid oils in broiler chicken diets." Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/666880.

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Los aceites ácidos son co-productos que derivan del proceso de refinación de los aceites para consumo humano (oleínas; aceites ácidos de refinación química y ácidos grasos destilados de refinación física). Se caracterizan por presentar un perfil en ácidos grasos (AG) similar al de los aceites crudos de los que derivan, pero se diferencian en su estructura molecular, ya que tienen un alto contenido en ácidos grasos libres (AGL), lo que puede afectar a su valor nutricional. El objetivo de la presente tesis es profundizar en el estudio de los procesos de digestión y absorción de la grasa en pollos de carne y determinar cómo se ven afectados por el nivel de saturación y nivel de AGL de la dieta y edad de los pollos. El primer ensayo (Capítulo 3) se llevó a cabo con el fin de evaluar el efecto del grado de saturación de la dieta y edad del pollo (14 d y 35 d) sobre los procesos de digestión y absorción de la grasa. Para ello se utilizaron dietas con un 6% de aceite crudo de soja y aceite crudo de palma. El segundo ensayo (Capítulos 4 y 5) se llevó a cabo para estudiar el efecto del nivel de AGL y grado de saturación de la dieta, así como también de la edad (14 d y 37 d) sobre los procesos de digestión y absorción de la grasa. Se utilizaron ocho dietas experimentales con dos grados de saturación (derivados del aceite de soja como fuente insaturada y del aceite de palma como fuente saturada) y cuatro niveles de acidez (5%, 15%, 35% y 50%). Para ello, se combinaron dos aceites crudos y dos co-productos ricos en AGL (oleínas). En ambos estudios se determinó la digestibilidad de los AG y el contenido en fracciones lipídicas a lo largo del tracto gastrointestinal (TGI; molleja, duodeno, yeyuno e íleon) y excreta. Los resultados demuestran que el yeyuno es el principal lugar de absorción de los AG y que la absorción está más afectada por la edad, grado de saturación y nivel de AGL de la dieta que la hidrólisis. La mayor utilización de las dietas insaturadas se confirmó tanto en pollos jóvenes como adultos y se relacionó con una mayor capacidad de absorción de los AG saturados a nivel del íleon. La mejora en la utilización de la grasa en pollos adultos se relacionó con una mayor absorción de los AG a nivel de yeyuno. Los resultados también evidencian que los pollos adultos (37 d) se vieron menos afectados por el nivel de AGL en la dieta que los pollos jóvenes (14 d), debido a que en los primeros la absorción de los AG a nivel de yeyuno fue más eficiente. Otro hallazgo interesante es que el aceite crudo de soja podría ser parcialmente reemplazado por el aceite ácido de soja de refinación química , cómo grasa alternativa, siempre y cuando no se supere el 15% y 35% de AGL en dietas de inicio y crecimiento-acabado, respectivamente. Por otro lado, no se observaron diferencias destacables entre los resultados obtenidos con dietas saturadas con 50% y 5% de AGL, lo que lleva a sugerir que el aceite ácido de palma (ácidos grasos destilados de refinación física de palma) podría reemplazar el aceite crudo de palma en dietas de crecimiento-acabado, al menos cuando no se supera el 50% de AGL de la dieta, sin que se produzcan repercusiones negativas sobre la utilización de la grasa de la dieta. Acid oils, fat by-products from the edible oil refining industry, are rich in free fatty acids (FFA), have similar fatty acid (FA) composition to their respective crude oils, but different molecular structures, which can affect their nutritional value. The aim of the present thesis is to study in depth the digestion and absorption of fat in broiler chickens, and determine how the age of the chickens, the saturation degree and the FFA level of dietary fat affect these processes in order to raise recommendations on the use of oils with certain percentages of FFA in the diets with no negative repercussions on fat utilization. The first trial (Chapter 3) was conducted in order to study the effect of the dietary fat saturation degree and age (14 d and 35 d) on the fat digestion and absorption processes. For this purpose the dietary use of crude soybean oil and crude palm oil was studied. The second trial (Chapters 4 and 5) was conducted to assess the effect of the dietary FFA level, fat saturation degree and age (14 d and 37 d) on fat digestion and absorption processes. Two crude oils and two fat by-products from the edible oil refining industry rich in FFA were used in order to produce eight dietary treatments with two different saturation degrees (soybean oil products as unsaturated fat source, and palm oil products as saturated fat source), and four levels of dietary FFA (5%, 15%, 35%, and 50%). In both trials the FA digestibility and lipid class composition were determined along the gastrointestinal tract (GIT; gizzard, duodenum, jejunum, and ileum), and excreta. The results evinced that the absorption process mainly takes place in the jejunum, and is more affected than the hydrolysis process is by the saturation degree and free fatty acid level of dietary fat, as well as by the age of the chicken. The greater utilization of unsaturated diets irrespective of the age was confirmed, which was mainly due to the higher contribution of the ileum, especially to saturated FA absorption. The improvement on fat utilization in adult broiler chickens was due to an increase in the contribution of the jejunum to FA absorption. The results also evinced that adult broiler chickens (37 d) were less affected by the dietary FFA level than young broiler chickens (14 d) were due to a more efficient FA absorption at the jejunum level. Another interesting finding is that crude soybean oil could be partially replaced by acid soybean oil from chemical refining, being a good alternative fat source to be used in broiler chicken diets at least when the dietary FFA level does not exceed 15% and 35% in starter and grower-finisher diets, respectively. On the other hand, the saturated diet with 50% dietary FFA level did not differ from the saturated diet with the lowest dietary FFA level (5%), suggesting that acid palm oil (palm fatty acid distillate) could replace crude palm oil in grower-finisher diets, at least when the FFA level does not exceed 50% with no negative repercussions on fat utilization compared to the use of crude palm oil. Regardless of the age, it was concluded that the FA profile of dietary fat has a bigger impact on fat utilization than the level of dietary FFA.

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Jackson, Gillian. "Monoamine release and turnover in broiler chicken brain." Thesis, University of Bristol, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.411086.

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Williams, Beverley Gail. "Aspects of bone quality in the broiler chicken." Thesis, University of Glasgow, 2000. http://theses.gla.ac.uk/6630/.

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The work contained in this thesis explores the development of the tibiotarsus shaft and the quality of cortical bone in the modern broiler, in relation to genetic background, growth rate and dietary mineral content. This was achieved through a series of experiments predominantly using a modern selected strain of broiler and an older, unselected control strain, and occasionally utilising current commercial stock. Birds were exposed to a variety of dietary mineral contents, and feeding regimes, and assessments were made of a number of aspects of bone quality, bone turnover, and mineral homeostasis at selected ages .A number of phases in tibiotarsus development were identified from the embryo through to slaughter age at approximately six weeks; these were seen in all strains of broiler chicken investigated. Resorption and replacement of the embryonic cartilage model of the tibiotarsus was found to begin before day 16 of incubation, and a reduction in cortical thickness was observed between this age and hatch as the marrow cavity was enlarged. During this period, the cortex was observed to develop from a maze like scaffold, to display recognisable Haversian canals with the new bone being rapidly mineralised; by day 6, the cortex displayed a distinctive pattern of Haversian canals which remained consistent throughout much of the bird's life-span. From hatch, cortical width began a rapid increase in thickness, which was seen to halt at approximately 18 days of age, cortical thickness remaining approximately constant from this age. The rapid increase in cortical mineral content was also seen to plateau at approximately 11 days.

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Kaminskienė, Jurga. "Mineralinių medžiagų panaudojimas dėsliųjų vištų ir viščiukų broilerių mityboje." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2008. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2008~D_20080317_134022-62942.

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Per pastaruosius 20 metų daug pasiekta auginant viščiukus broilerius – ženkliai padidėjo viščiukų augimo greitis ir maisto pasisavinimo efektyvumas. Šiuolaikiniai komerciniai hibridai greitai vystosi ir jiems reikia daug energijos turinčių lesalų, kurie leidžia maksimaliai išnaudoti jų genetines galimybes. Daugiau pasiekta ir vištų dedeklių lesinime balansuojant lesalus skirtingais dėslumo etapais, ypač ankstyvojo dėjimo periodu. Pastaruoju metu paukščių lesinime didelis dėmesys skiriamas optimaliam kalcio, fosforo, natrio, kalio ir chloro subalansavimui. Parinkus netinkamas kalcį ir fosforą nešančias medžiagas, taip pat nesubalansavus natrio, kalio ir chloro tarpusavio santykio, t.y. anijonų katijonų balanso, padidėja vandens suvartojimas, sutrinka virškinimo trakto mikrobiologinė pusiausvyra, blogėja kraiko kokybė ir mikroklimato parametrai, susidaro sąlygos paukščiams susirgti ascitais, padaugėja paukščių staigių gaišimo atvejų. Vitaminai ir mineralai yra svarbi sudedamoji paukščių raciono dalis. Šios medžiagos įtraukiamos į racioną kaip priedai atitinkamais kiekiais, kad būtų patenkintas jų poreikis sveikiems produkciją duodantiems paukščiams. Mineralų ir vitaminų trūkumas gali būti kritiškas tam tikrais organizmo vystymosi etapais, todėl kai kurie autoriai teigia, kad net ir trumpas vitaminų bei mineralų apribojimas augimo fazės metu gali turėti neigiamų pasekmių. Magistrinio darbo tikslas – nustatyti mineralinių medžiagų įtaką dėsliųjų vištų ir viščiukų broilerių... [toliau žr. visą tekstą] Minerals play a very important role in digestion and metabolism of poultry. They are necessary, for the maintenance, growth, production and health of birds. Laying hens also require minerals, primarily calcium, for eggshell formation. Minerals is divided into the macrominerals (those needed in relatively large amounts) and the micro- or trace minerals. Although microminerals are required only in small amounts, the lack of an adequate dietary supply can be just as detrimental to poultry as a lack of one of the macrominerals. Grains are low in minerals, so all poultry feeds contain supplemental sources. Calcium, phosphorus and salt are needed in the greatest amounts. Microminerals such as iron, copper, zinc, manganese and iodine are normally supplied through a trace mineral mix. The minerals influence by the bird‘s physiological status, requirement of minerals and its source is describe in the theory part. Two experiment were performed with broiler chickens and laying hens. The feed intake, feed conversion ratio, birds mortality, the degree of mineralization in the bone tibia, pH, macroelements Ca, P, Mg, Na, K, Cl and alkaline phosphatase in the blood serm were researched in experiment of broiler chickens. Number and weight of eggs, body weight, laying intensity, leftover and utilization of feed to get 1 kg eggs mass, quality parameters of eggshells, the physiological conditions and mortality reasons were researched in test of laying hens. Conclusions. Sodium bicarbonate was... [to full text]

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Owens, B. "Alternatives to antibiotic growth promoters for broiler chicken production." Thesis, Queen's University Belfast, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.411368.

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Karlsson, Louise. "The Rowan Ranger Chicken Breed - a Suitable Alternative for the Organic Chicken Meat Industry." Thesis, Linköpings universitet, Biologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-129085.

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The only available broiler strain to use in organic chicken meat production, until recently, has been conventional fast growing broiler hybrids. The Rowan Ranger is a broiler strain that has a naturally slower growth rate which makes this strain suitable for organic farming, meeting the demands of KRAV without being subjected to a feed restriction. One of the farms in Sweden using Rowan Ranger in their organic production is Bosarp farm in Skåne County where they produce KRAV certified chickens and where the animals used in this study were raised. This study compared differences between a naturally slow growing strain of chicken to a fast growing strain to see whether there were differences in behaviour between the two, if one of the strains was more susceptive to stress than the other and whether they differed in outdoor use and activity level. Regardless of strain, chickens used the outdoor perimeter the same, although the Rowan Rangers did not range as far from the chicken house as Ross 308. Even so, they seem to be more suitable in an organic setting than Ross 308 due to the fact that they seem less hungry and more content, this based on the fact that they perform less feeding behaviour and spend more time laying down. Also, they grow nicely to slaughter weight with a good diet quality whereas Ross 308 need to be qualitative feed restricted to do the same, giving the Rowan Rangers better welfare.

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Mafiri, Matseko Nkele. "Effect of supplementing diets with effective microorganisms on intake, growth and carcass characteristics of ross 308 broiler chickens." Thesis, University of Limpopo, 2014. http://hdl.handle.net/10386/1390.

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Thesis (M.Sc. (Animal Production)) -- University of Limpopo, 2014 Two experiments were conducted to determine the effects of supplementing diets with effective microorganisms on intake, growth and carcass characteristics of Ross 308 broiler chickens. The first experiment determined the effect of supplementing diets with effective microorganisms on performance of unsexed Ross 308 broiler chickens aged one to three weeks. Two hundred unsexed day-old chicks were randomly assigned to five treatments with four replications, each replication having ten birds. A complete randomized design was used. The chickens were fed a grower diet supplemented with 0 (EM0), 30 (EM30), 50 (EM50), 70 (EM70) or 100 (EM100) ml of effective microorganisms per litre of water. Effective microorganism supplementation did not improve (P>0.05) diet and metabolisable energy intakes of the chickens. Effective microorganism supplementation reduced (P<0.05) growth rate and live weight of the chickens. Poorer (P<0.05) feed conversion ratios were observed in chickens supplemented with effective microorganisms. However, effective microorganism supplementation improved (P<0.05) crude protein retention of the chickens. Supplementation with effective microorganisms reduced (P<0.05) mortality rate of the chickens from 10 to 0 %. The second experiment determined the effect of supplementing diets with effective microorganisms on performance of male Ross 308 broiler chickens aged 22 to 42 days. The chickens were randomly allocated to five treatments with four replications, each replication having 10 birds. The chickens aged 21 days, weighing 474 ± 2g, were allocated to the treatments in a complete randomized design. The chickens were fed a grower diet supplemented with 0 (EMM0), 30 (EMM30), 50 (EMM50, 70 (EMM70) or 100 (EMM100) ml of effective microorganisms per litre of water. Effective microorganism supplementation did not improve (P>0.05) intake, DM digestibility, metabolisable energy, feed conversion ratio, fat pad weight and meat sensory attributes of the chickens. Effective microorganism supplementation reduced (P<0.05) growth rate, live weight and carcass weight of the chickens. However, effective microorganism supplementation improved (P<0.05) crude protein retention and crude protein content of meat of the chickens. Supplementation with effective microorganisms reduced (P<0.05) mortality of the chickens from 5 to 0 %. v It is concluded that effective microorganism supplementation to the diets of Ross 308 broiler chickens reduced growth rate and live weight of the chickens. However, effective microorganism supplementation improved crude protein retention and crude protein content of the meat of broiler chickens. Supplementation with effective microorganisms reduced mortality of the chickens to zero.

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Ngomani, Delisile. "Effect of dietary threonine level on productivity and carcass characteristics of Ross 308 broiler chickens." Thesis, University of Limpopo, 2019. http://hdl.handle.net/10386/3052.

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Thesis (M.Sc. (Animal Production)) --University of Limpopo, 2019 Two experiments were conducted to determine the effect of dietary threonine level on production performance and carcass characteristics of Ross 308 broiler chickens. In each experiment the diets were isocaloric and isonitrogenous but with different dietary threonine levels.The first part of the study determined the effect of dietary threonine level on feed intake, growth rate, mortality and carcass characteristics of Ross 308 broiler chickens aged between Day 1-21. A total of 150 unsexed day-old chicks were used in a complete randomized design having 5 treatments (6.4, 7.5, 8, 8.5 and 9g of threonine/kg DM feed), replicated three times and having ten chickens per replicate. The second part of the study determined the effect of dietary threonine level on feed intake, digestibility, growth rate, mortality and carcass characteristics of male Ross 308 broiler chickens aged between Day 22-42. Seventy-five male chickens were used in a complete randomized design having 5 treatments (6.4, 7.5, 8, 8.5 and 9g of threonine/kg DM feed), replicated three times and having five chickens per replicate. A quadratic regression model was used to determine the optimal productivity of the chickens while a General Linear Model (GLM) procedures for the statistical analysis of variance was used to detect dietary treatment effects. Where there were significant differences (P<0.05), Turkey’s honestly significant difference test (HSD) was used for mean separation. The chickens were slaughtered at the ages of 21 and 42 days for Experiments 1 and 2, respectively, following ethical standards as recommended by the University of Limpopo Animal Research Ethics Committee (AREC/12/2017: PG). Two chickens per replicate for both studies were slaughtered for the determination of carcass characteristics (carcass and organ weights, gut organ digesta pH and gastro-intestinal length measurements). Dietary threonine levels used in this experiment affected (P<0.05) feed intake, growth rate, live weight, metabolisable energy (ME) intake, nitrogen retention, feed conversion ratio and gut organ weights and lengths of unsexed Ross 308 broiler chickens aged 21 days. Dietary threonine level did not affect (P>0.05) diet digestibility. Feed conversion ratio, pH of the proventriculus digesta, gut intestine length and caecum length of unsexed broiler chickens were optimized at different dietary threonine levels of 9.6, 8.5, 6.6 and 8.4 g/kg DM, respectively. Dietary threonine levels had an effect (P<0.05) on feed intake, diet digestibility, metabolizable energy, live weight, proventriculus pH values, GIT length, gut organ and carcass organ weights of male Ross 308 broiler chickens between 22 to 42 days of age. Proventriculus and large intestine weights were optimized at different dietary threonine levels of 7.5 and 9.1 g/kg DM feed, respectively. Dietary threonine level did not affect (P>0.05) growth rate, feed conversion ratio of male Ross 308 broiler chickens between 22 to 42 days of age. It is concluded that dietary threonine levels used in this study affected production performance of younger broilers (Day 1-21) more than that of older birds (Day 22-42). However, production variables were optimized at different dietary threonine levels. This has implication on diet formulation for the chickens and no linear response could be established National Research Foundation (NRF), and the Department of Agriculture, Forestry and Fisheries (DAFF)

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Hamdi, Manel. "Dietary factors influencing calcium and phosphorus utilization in broiler chicken." Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/400305.

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Urdaneta, Rincon Maria. "Mild feed restriction and compensatory growth in the broiler chicken." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0021/MQ55722.pdf.

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Paxton, Heather. "Locomotor design constraints and musculoskeletal compromises in the broiler chicken." Thesis, Royal Veterinary College (University of London), 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.572144.

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Aitchison, Mia. "Energy efficiency and nutrient partitioning in the modern broiler chicken." Thesis, University of Aberdeen, 2014. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=225709.

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Vilarrasa, Gustems Ester. "Use of re-esterified oils in pig and broiler chicken diets." Doctoral thesis, Universitat Autònoma de Barcelona, 2015. http://hdl.handle.net/10803/287900.

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La incorporació de matèries grasses és una pràctica habitual en la formulació de pinsos per a porcs i pollastres. Els olis àcids són subproductes de la indústria de refinació d’olis, donant lloc a matèries primeres sostenibles i interessants des del punt de vista econòmic. Ara bé, el seu elevat contingut en àcids grassos (AG) lliures, fa que el seu valor nutritiu sigui inferior al del seu corresponent oli natiu. Podem neutralitzar els AG lliures dels olis àcids a través de la seva esterificació amb glicerol (subproducte de la indústria del biodièsel), obtenint, com a producte final d’aquest procés, els olis re-esterificats. La diferent estructura molecular dels olis re-esterificats pot millorar el seu valor nutritiu i, en particular, l’absorció dels AG saturats. Per tot plegat, l’objectiu global d’aquesta tesi va ser investigar l’ús potencial dels olis re-esterificats en l’alimentació de porcs i pollastres. La caracterització dels greixos (Capítol 3, 4 i 5) va mostrar que els olis re-esterificats presentaven la mateixa composició en AG que la dels seus corresponents olis natius, però una major proporció d’AG saturats situats a la posició sn-2 de les molècules d’acilglicerols, i una major quantitat de mono- i diglicèrids (amb els AG principalment esterificats a les posicions sn-1,3), el que va donar lloc a un menor contingut en energia bruta. Als tres primers experiments (Capítol 3, 4 i 5), es va comparar l’ús de dos olis re-esterificats de palma (amb baix i alt contingut en mono- i diglicèrids) amb el del seu corresponent oli àcid (control negatiu) i oli natiu (control positiu). D’una banda, no es van observar diferències en els coeficients d’absorció dels AG entre els animals alimentats amb l’oli natiu i els alimentats amb l’oli àcid de palma (excepte en pollets de primera edat). Per tant, els olis àcids de palma poden considerar-se una font de greix alternativa en l’alimentació d’animals monogàstrics, sempre que tinguin < 60% d’AG lliures i < 3% d’humitat, impureses i fracció insaponificable. D’altra banda, els animals alimentats amb olis re-esterificats de palma van assolir coeficients d’absorció similars o inclús superiors als dels animals alimentats amb el seu corresponent oli natiu, encara que es van observar algunes peculiaritats en funció de l’espècie i de l’estat fisiològic dels animals. En pollastres (Capítol 5), el grau de saturació del greix va exercir un major impacte en l’absorció aparent dels AG que l’estructura molecular del greix. Per aquest motiu, en l’últim experiment (Capítol 6) es va investigar quina seria la millor estratègia nutricional (olis re-esterificats purs o mescles) per obtenir la millor eficiència en termes d’absorció aparent dels AG. La substitució de l’oli re-esterificat de palma per oli re-esterificat de soja va millorar l’absorció aparent dels AG totals, encara que no es va observar sinergisme entre els dos olis re-esterificats. Una altra troballa interessant va ser que, independentment de la font de greix, de l’espècie i de l’estat fisiològic dels animals, la fracció lipídica eliminada per les femtes i les excretes estava principalment constituïda per AG lliures, el que suggereix que el factor limitant del procés d’absorció del greix de la dieta no és el procés d’hidròlisi lipídica, sinó el procés de solubilització micel·lar. Per tot això, podem considerar que, des d’un punt de vista nutricional, els olis re-esterificats són una bona font de greix alternativa per ser utilitzats en l’alimentació d’animals monogàstrics. Això no obstant, i degut a que el procés d’esterificació suposa un cost afegit, la seva viabilitat econòmica dependrà del preu diferencial entre l’oli natiu i l’oli àcid. The addition of fat sources in pig and broiler-chicken diets is a common practice. Acid oils are by-products from oil refining industry, resulting in sustainable and economically interesting raw materials. However, they have a lower nutritive value than their corresponding native oil, due to their high free fatty acid (FA) content. We can neutralize the free FA content of acid oils through their esterification with glycerol (by-product from biodiesel industry). Re-esterified oils are the end products of this process. The different molecular structure of re-esterified oils may enhance the apparent absorption of saturated FA and, consequently, their overall nutritive value. Therefore, the global aim of this thesis was to investigate the potential use of re-esterified oils in pig and broiler-chicken diets. Fat characterization (Chapter 3, 4 and 5) showed how re-esterified oils had the same FA composition as their corresponding native oils, but a greater proportion of saturated FA located at the acylglycerol sn-2 position and a greater amount of mono- and diacylglycerols (with FA mainly esterified at the sn-1,3 positions), which resulted in a lower gross energy content. In the first three experiments (Chapter 3, 4 and 5), the use of two re-esterified oils (with a low and a high mono- and diacylglycerol content) was compared with that of their corresponding acid (negative control) and native (positive control) oils. On one hand, no differences in FA apparent absorption coefficients were observed between animals fed native or acid palm oils (except in young broiler chickens). Thus, acid palm oils can be considered interesting alternative fat sources to be used in monogastric-animal diets, provided they have < 60% of free FA and < 3% of moisture, impurities, and unsaponifiable matter. On the other hand, animals fed re-esterified palm oils achieved similar or even better apparent absorption coefficients than those fed their corresponding native oil, although some peculiarities were observed according to the species and the physiological state of the animals. In broiler chickens (Chapter 5), the fat degree of saturation exerted a greater impact on FA apparent absorption than did the fat molecular structure. For this reason, in the last experiment (Chapter 6), the best nutritional strategy (pure re-esterified oils or blends of re-esterified oils) was investigated, in order to obtain the best efficiency in terms of FA apparent absorption. The addition of re-esterified soybean oil in replacement of re-esterified palm oil in broiler chicken diets improved the total FA apparent absorption, although no synergism was observed between re-esterified oils. Another interesting finding was that, regardless of the dietary fat source, the species, and the physiological sate of the animals, fat lost in feces or excreta was mainly composed of free FA, which suggests that micelle formation, and not fat hydrolysis, is the rate-limiting step of fat absorption. Taken together, from a nutritional point of view, re-esterified oils are good, alternative fat sources to be used in monogastric-animal diets. However, considering that the esterification process represents an additional cost, the economic viability of re-esterified oils will depend on the price differential between native and acid oils.

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Thee, Jelvia Amianco Chemical Sciences &amp Engineering Faculty of Engineering UNSW. "Enrichment techniques for enhanced detection of campylobacter in broiler chicken carcasses." Awarded by:University of New South Wales. Chemical Sciences & Engineering, 2009. http://handle.unsw.edu.au/1959.4/43420.

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Campylobacter has been known for more than a century and today Campylobacter infection is considered the leading cause of bacterial foodborne disease in the developed world. Consumption of undercooked poultry and/ or handling of raw poultry are seen as the main transmissions of Campylobacterto humans due to high levels (107 and 108 CFUlg) of C.jejunifound in the intestinal tract of raw poultry. Several studies have suggested that by delaying addition of antibiotics for 2 h at 37??C there was a better recovery of Campylobacter in food samples. Rinses from sixty whole carcasses were treated to non-pre-enrichment incubation and preenrichment at 37??C or 42??C for 2, 4 and 6h. Using TECRA?????? CAMVIA immunoassay method, results showed that 100% of the carcasses were positive for Campylobacter when the pre-enrichment techniques was applied compared to just 30-60% positive results from non pre-enrichment techniques. To develop more efficient enrichment methods, thirty carcass rinses were incubated in Bolton, Preston and TECRA??? broth under aerobic and microaerobic atmosphere at 25??C and 42??C. Results' from TECRA??? CAMVIA revealed that recovery of Campylobacter spp. from TECRA??? broth under aerobic conditions and Bolton or Preston broth under microaerobic conditions are not significantly different (p > 0.05). Charcoal based CCDA and Karmali agar were as effective as blood based Campy-Cefex agar in isolating Campylobacter spp. although Karmali was better in suppressing the growth of background microflora. Twenty samples of retail poultry carcasses, offal, portion chicken, mince respectively and ten samples of each fresh chicken sausages and frozen nuggets respectively were enriched in TECRA??? and Preston broths for recovery of Campylobacter. TECRA??? CAMVIA showed that 100% (TECRA??? and Preston) of the portion chicken was Campylobacter positive compared to 80 (TECRA???)-100% (Preston) of liver, 90 (TECRA???)-1 00% (Preston) of minced chicken and 65 (TECRA???)-75% (Preston) of carcasses. The difference between the two broths to recover Campylobacter spp. was not significant.

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Mbajiorgu, Christian A. "Effect of time of initiation of feeding after hatching and influence of dietary lysine and ascorbic acid supplementation on productivity and mortality of Ross 308 broiler chickens." Thesis, University of Limpopo (Turfloop Campus), 2007. http://hdl.handle.net/10386/692.

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Thesis (M.Sc. (Animal Production)) --University of Limpopo, 2007 Two experiments were conducted to evaluate the effect of time of initiation of feeding after hatching and influence of dietary lysine and ascorbic acid supplementation on productivity, carcass characteristics and mortality of Ross 308 broiler chickens. The first experiment examined the effect of time of initiation of feeding after hatching and influence of dietary lysine supplementation during realimentation on productivity, carcass characteristics and mortality of Ross 308 broiler chickens during the winter period. Three hundred and sixty unsexed Ross 308 broiler chickens with an initial weight of 30 ± 2 g per bird were assigned to twelve treatments with three replications of ten birds each in a 4 (times of initiation of feeding) x 3 (lysine supplemental levels) factorial, complete randomized design. At each time of initiation of feeding after hatching during the starter and grower stages, the diets were isocaloric and isonitrogenous but with three different lysine supplementation levels. Lysine supplementation started three days after hatching. Time of initiation of feeding above 36 hours after hatching resulted in growth retardation and high mortality rate. More than 50 % of the birds died between one and three days of age when initiation of feeding after hatching was above 36 hours. However, the birds ‘caught-up’ at the latest within eight days of realimentation. This compensatory growth could be explained in terms of higher intakes. Lysine supplementation during realimentation reduced the number of days of ‘catch-up’ irrespective of time of initiation of feeding after hatching. Generally, the higher the level of lysine supplementation, the lower was the number of days of ‘catch-up’ upon realimentation. Thereafter, time of initiation of feeding after hatching and lysine supplementation had no effect (P>0.05) on live weight, feed intake, growth rate, feed conversion ratio, diet digestibility, nitrogen content of breast meat, dressing %, carcass characteristics and mortality of Ross 308 broiler chickens. The second experiment examined the effect of time of initiation of feeding after hatching and influence of dietary ascorbic acid supplementation on productivity, carcass characteristics and mortality of Ross 308 broiler chickens during the summer period. Six v hundred and seventy five unsexed Ross 308 broiler chickens with an initial weight of 32 ± 2 g per bird were assigned to fifteen treatments with three replications of fifteen birds each in a 3 (times of initiation of feeding) x 5 (ascorbic acid supplemental levels) factorial, complete randomized design. Ascorbic acid supplementation started 3 days after hatching. An average of 18 % and 31 % of the birds died between one and three days of age when initiation of feeding after hatching was above 36 hours. However, the birds ‘caught-up’ within ten days of realimentation irrespective of time of initiation of feeding after hatching. This compensatory growth could be explained in terms of reduced maintenance requirement and possibly, increased efficiency of growth. Following ‘catch-up’, ascorbic acid supplementation during realimentation lowered (P<0.05) mortality rate and improved growth rates irrespective of time of initiation of feeding after hatching. Growth rate increased incrementally with increasing levels of ascorbic acid supplementation within each time of initiation of feeding after hatching. Improved growth rate in the ascorbic acid supplemented birds resulted in improved live weight in comparison with those without ascorbic acid supplementation at 21 days of age and continued until 42 days of age. Live weight increased incrementally with increasing levels of ascorbic acid supplementation within each time of initiation of feeding after hatching. Similarly, increasing ascorbic acid supplementation within each time of initiation of feeding after hatching increased dressing percentage and breast meat yield at 42 days old. However, ascorbic acid supplementation had no effect (P>0.05) on feed intake of the birds irrespective of time of initiation of feeding after hatching. In both experiments, mortality was positively and strongly correlated with time of initiation of feeding after hatching while live weight was negatively and strongly correlated with time of initiation of feeding after hatching. It is concluded that time of initiation of feeding above 36 hours after hatching is not desirable, mainly because of its effect on mortality. However, lysine supplementation in the diet of broiler chickens subjected to delayed initiation of feeding after hatching might play a key role in accelerating the rate of ‘catch-up’ growth response. vi It is also concluded that the beneficial effect of ascorbic acid supplementation could be exploited in reducing mortality rate and improving growth rates in broiler chickens subjected to delayed initiation of feeding after hatching. the National Research Foundation

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Molepo, Lephai Sarah. "Effect of moringa seed meal supplementation on productivity and carcass characterictics of ross 308 broiler chickens." Thesis, University of Limpopo, 2014. http://hdl.handle.net/10386/1363.

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Thesis (MSC. Agriculture (Animal Production)) --University of Limpopo, 2014 Two experiments were conducted to determine the effect of moringa seed meal supplementation on productivity and carcass characteristics of Ross 308 broiler chickens. The first experiment determined the effect of moringa seed meal supplementation on productivity of Ross 308 broiler chickens aged one to 21 days. Two hundred and fifty unsexed day-old Ross 308 broiler chicks were randomly allocated to five dietary treatments, replicated five times, and each replication having 10 chickens. A completely randomized design was used. The chickens were fed on a grower diet supplemented with 0 (M0), 5 (M5), 10 (M10), 15 (M15) and 20 (M20) g of moringa seed meal/bird/day. Moringa seed meal supplementation had no effect (P>0.05) on feed intake, metabolisable energy intake, nitrogen retention, feed conversion ratio and live weight of unsexed Ross 308 broiler chickens. Moringa seed meal supplementation improved (P<0.05) growth rates of unsexed Ross 308 broiler chickens aged one to 21 days. A moringa seed meal supplementation level of 13.3 g/kg DM feed optimized growth rate of Ross 308 broiler chickens aged one to 21 days. The second experiment determined the effect of moringa seed meal supplementation on productivity and carcass characteristics of female Ross 308 broiler chickens aged 22 to 42 days. The chickens weighing 558 ± 10 g/bird were randomly allocated to five treatments with five replications having 10 birds. The chickens, aged 21 days, were allocated to the treatments in a completely randomized design. The chickens were fed on a grower diet supplemented with 0 (FM0), 5 (FM5), 10 (FM10), 15 (FM15) and 20 (FM20) g of moringa seed meal per kg DM. Moringa seed meal supplementation had no effect (P>0.05) on feed intake, growth rate, feed conversion ratio, live weight, metabolisable energy intake, carcass weight, breast meat weight, abdominal fat pad weight, liver weight, heart weight, thigh weight, meat flavour, juiciness and tenderness of female Ross 308 broiler chickens. However, moringa seed meal supplementation improved (P<0.05) nitrogen retention and gizzard weights of female Ross 308 broiler chickens. vi It was concluded that moringa seed meal supplementation improved growth rate of unsexed Ross 308 broiler chickens aged one to 21 days. Similarly, moringa seed meal supplementation increased nitrogen retention and gizzard weights of female Ross 308 broiler chickens aged 22 to 42 days.

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Anderson, Mallory Grace. "Chicken or fish? Do environmental complexity and stocking density impact affective states of broiler chickens and rainbow trout?" Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/105133.

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In commercial settings, broiler chickens and rainbow trout are housed in barren environments under high stocking densities, due to an emphasis on production efficiency. These monotonous housing conditions do not provide broilers or trout with the ability to perform functional, highly-motivated behaviors and increase their susceptibility to excessive anxiety and fear, resulting in negative affective states and poor animal welfare. Affective state (or emotional state) is a cumulative product of short-term life experiences, ranging from positive to negative. Because affective states are largely influenced by environmental condition, determining animal affective state can provide useful information on how to improve housing conditions in order to ensure positive experiences and good animal welfare. Cognitive processes are closely associated with affective state; a "cognitive bias" occurs when affective state influences aspects of cognition, such as judgement and attention. Animals in positive affective states make optimistically-biased decisions during ambiguous situations, judging the situation as if it will produce a positive outcome, and show less bias towards a perceived threat, responding in a less anxious and calm manner. Animals in negative affective states make pessimistically-biased decisions during ambiguous situations, judging the situation as if it will result in a negative outcome. Additionally, animals in negative affective states will bias their attention towards a perceived threat rather than alternative stimuli, responding in an anxious manner. Therefore, judgement and attention bias tests can be used to determine animal affective states. In Chapter 3, a judgement bias test was used to determine affective state of broiler chickens housed in either complex (perches, dust bath, pecking stones, and rotating enrichment objects) or barren (no enrichment) environments under either high or low stocking densities. Broilers housed in complex environments responded more optimistically during the judgement bias test than broilers from barren environments, indicating the former were in a positive affective state. Stocking density did not impact their responses in the judgement bias test, indicating that affective states were not impacted by that treatment. In Chapter 4, an attention bias test was used to determine level of anxiety and a tonic immobility test was used to determine fear in order to investigate affective state of broilers housed in the same conditions as described for Chapter 3. Broilers housed in complex environments were less anxious during the attention bias test than broilers from barren environments, indicating environmental complexity reduced anxiety in broilers. Stocking density did not impact anxiety. Broilers from high stocking density environments had shorter tonic immobility durations than broilers from low stocking density environments, suggesting the former were less fearful. Environmental complexity did not impact fearfulness. In Chapter 5, a judgement bias test was used to determine affective state of rainbow trout housed in either complex (shelter structure and artificial plants) or barren (no enrichment) tanks under either low or high stocking densities. Trout housed in high stocking density tanks responded optimistically during the judgement bias test, indicating they were in a more positive affective state compared to trout housed in low stocking density tanks. Environmental complexity did not impact their responses in the judgement bias test, indicating no effect of enrichments on affective states was found. These results indicate a beneficial relationship of a complex environment on broiler chicken affective state, observed through an optimistic judgement bias and reduced attention bias (anxiety) towards a perceived threat. Thus, providing a complex housing environment for broilers can improve their welfare and result in a positive affective state. Rainbow trout reared at the tested high density resulted in a positive affective state, although complexity did not benefit their welfare. Our results contribute much needed information on stocking densities to ensure fish welfare. Overall, environmental complexity, not stocking density, had a positive impact on broiler chicken affective states. Rainbow trout affective states were positively impacted by stocking density, but not environmental complexity. Master of Science Conventional housing of broiler chickens and rainbow trout (both raised for meat) causes concern for their welfare and affective states. Environmental conditions can greatly impact animals' affective states–their long-term emotional state, ranging from positive to negative. In barren environments at high stocking densities, broiler chickens and rainbow trout are prevented from showing normal behaviors and these conditions can compromise their affective state and welfare. By 'asking' chickens and trout whether the glass is half full or half empty, we can determine level of optimism or pessimism, and level of anxiety or calmness, therefore gaining a better understanding of their affective states. This can be done using a judgement bias test and attention bias test, where animal responses (optimism and anxiety) are recorded during ambiguous situations (judgement) and threatening situations (attention). Animals in positive affective states judge ambiguous situations optimistically (glass half full) and pay little attention towards perceived threats, while animals in negative affective states judge the same ambiguous situations pessimistically (glass half empty) and pay more attention towards perceived threats. In Chapter 3, responses to ambiguous situations were used to determine the affective state of broiler chickens housed in either enriched (perches, dust bath, pecking stones, rotating toys) or barren environments at either high or low stocking densities. Broiler chickens housed in enriched environments had an optimistic judgement bias of ambiguous situations (glass half full), suggesting they were in a more positive affective state compared to broilers housed in barren environments. Stocking density did not impact their level of optimism. In Chapter 4, responses to a perceived threat were used to determine level of anxiety and a tonic immobility test was used to determine fear of broilers housed under the same conditions as in Chapter 3. Broilers housed in enriched environments paid less attention to a perceived threat than broilers housed in barren environments, indicating the former were less anxious (glass half full) and in a positive affective state. Fear was not impacted by the tested enrichments, but birds kept under higher stocking densities did show reduced fear compared to birds in low-density environments. In Chapter 5, rainbow trout were housed in either enriched (shelter structure and artificial plants) or barren tanks at either high or low stocking densities. Affective state was evaluated through their responses to ambiguous situations. Trout housed in high stocking density environments had an optimistic judgement bias of ambiguous situations (glass half full), suggesting they were in a more positive affective state than trout housed in low stocking density environments. The enrichments did not impact their responses during the test, suggesting they did not impact fish optimism. These results indicate that an enriched environment improves broiler affective state and welfare compared to conventional housing conditions, the tested densities did not impact their welfare. Although an enriched environment did not positively impact responses of trout during ambiguous situations, our results show that housing rainbow trout in large groups results in a positive affective state and improved welfare status compared to housing trout in small groups. Overall, environmental enrichment, not stocking density, had a positive impact on broiler chicken affective states. Rainbow trout affective states were positively impacted by stocking density, but not environmental enrichment.

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Davids, Patricia (Tracey). "Playing chicken : the players, rules and future of South African broiler production." Diss., University of Pretoria, 2013. http://hdl.handle.net/2263/41069.

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The South African broiler industry is the greatest contributor to the South African agricultural sector, while at the same time providing the cheapest form of protein to the South African consumer. In light of a recent application for increased tariffs due to the industry’s inability to compete with the price of imported products, the need for a tool that is able to quantify the benefit of increased tariff protection to producers, while at the same time considering the cost of increased tariffs on South African consumers became apparent. The integrated nature of the industry however raised the concern that the assumptions associated with traditional quantitative modelling techniques, particularly that of a perfectly competitive market, would not allow the current broiler model within the BFAP sector modelling framework to represent the industry accurately. The primary objective of the study was to determine the true method of price discovery within the South African broiler market, in order to specify a price equation that is able to capture the dynamics surrounding price formation with improved accuracy. This price formation mechanism was then integrated into a simulation model that represents the industry accurately. Due to its ability to represent reality within the market with greater accuracy, the New Institutional Economic (NIE) framework was used to analyse the structure of the South African broiler industry as action domain. The actors and activities in the value chain were evaluated, followed by an analysis of the institutions that govern exchange within the market, highlighting the implications of these institutions for price formation within this coordinated market structure. Upon evaluation of compensation structures used within broiler production contracts, it became evident that the market for live broilers produced by contract growers could be considered as a market for grower services, as opposed to a market for live broilers. Compensation based on a broiler production tournament offers significant incentives for greater efficiency, effectively ensuring that production efficiency increases on a continuous basis. Despite the contractual obligation of integrated producers to pay their contracted growers based on a formula including the cost of production, the broiler producer price is negotiated between integrators and retailer, within a concentrated market structure. The cost of production is used as bargaining tool in price negotiations, yet the availability of imported products at extremely competitive prices limits the extent to which increased production costs can be passed up through the value chain. This was confirmed by the fact that the response of the domestic broiler producer price was much more elastic to changes in the international price than to changes in feed costs. The theoretical factors that drive broiler producer prices in South Africa were confirmed econometrically through the use of an error correction model, estimated empirically using secondary monthly data from 2007 to 2012. The estimated equations were integrated into a partial equilibrium framework using an import identity to establish equilibrium in the market, rather than a price equilibrator. The inelastic response from the domestic broiler producer price to changes in broiler feed prices raised questions regarding South African producers’ ability to compete with imported products and produce sustainably in the long run. Given the higher costs of production domestically, as well as the relative size and importance of the broiler industry within the South African agricultural sector, the need to evaluate the tariff application objectively was clear. Policy decisions should weigh the benefit of increased producer prices on broiler producers against the cost of protective policy to consumers, while also considering the specific consumers that would be required to bear the cost of increased tariffs. Integration of the partial equilibrium model of the broiler industry into the BFAP sector modelling framework enabled the simulation of various tariff scenarios, quantifying the effect on the agricultural sector, as well as chicken consumption. At the same time, the successful simulation of different scenarios and policy shocks validated the model. Simulation of the tariffs applied for by SAPA resulted in a producer price increase of 6%, which would be a significant margin on the bottom line for domestic producers. The cost to consumers of a 3.3% increase in retail prices also seems digestible; however the underlying factors that drive competitiveness should also be addressed in order to ensure long run sustainability for the industry. Dissertation (MSc Agric)--University of Pretoria, 2013. gm2014 Agricultural Economics, Extension and Rural Development unrestricted

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Britz, Jacobus Petrus. "Feed buying behaviour of small–scale broiler farmers / Britz J.P." Thesis, North-West University, 2011. http://hdl.handle.net/10394/7328.

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The South African poultry industry is a large part of the agricultural industry and a very important contributor to the Agriculture’s Gross Domestic Product. Furthermore, this industry is expanding and very good growth is predicted for the next decade. This growth will take place in the formal as well as the informal segments of the industry. The informal segment holds a lot of potential for suppliers to supply in their growing needs. Due to the fact that broiler feed is seen as a large contributor to the total cost of broiler production, it is considered very important factor. If feed suppliers want to focus on the informal market, they need to understand the differences between commercial farmers and small–scale farmers and specifically the different needs of small–scale farmers. To develop a strategy to utilize the opportunities in the informal market, it is necessary to understand all the factors that influence the purchase behaviour of these farmers. A model of stimulus response is used to define the factors that may influence purchase behaviour. The factors that seemed important from the literature study are market and other stimuli. The market stimuli consist of product, price, promotion and place. The product aspect could further be divided into quality aspects, brand equity, and additional services that accompany the product. Other stimuli that could influence purchase behaviour are economic conditions, special event, climatic condition and the influence of culture. Data was collected by means of a questionnaire. Descriptive statistics and factor analysis were used on the data to determine which factors influence the small–scale farmers’ purchase behaviour. While the Kaiser Meyer Olkin measure, Bartlett’s test of shericity and Cronbach Apha were used to determine if the data is suitable to do a factor analysis on. Factor analysis was done to determine which factors are the most important. The seven significant factors that influence the purchase behaviour of small–scale farmers are: * Value for money and opportunity. * Perceived brand value. * Customer support and service. * Consensus on available quality. * Brand loyalty. * Feed price at the reseller. * Bag size. More research on this topic in a larger geographical area is required. Thesis (M.B.A.)--North-West University, Potchefstroom Campus, 2012.

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Miller, Elizabeth. "Farming Without Farmers: Deskilling in Contract Broiler Farming." Thesis, University of Oregon, 2019. http://hdl.handle.net/1794/24222.

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Social scientists and food studies scholars have shown an enduring interest in how food is produced in our largely industrialized food system. However, there has been little research about the organization of labor on industrialized farms. These sites of production are mostly privately owned and hidden away from researchers and journalists, who are often perceived as critics or activists by farmers and other agriculturalists. My dissertation fills this gap by focusing exclusively on industrialized contract broiler farms. Contract broiler farming is a model where farmers agree to raise chickens for meat for a set amount of time, at a rate of pay based on the ratio of feed to chicken weight at slaughter. Farmers invest in the built infrastructure to execute this process, but the company they contract for is mostly in control of the upstream and downstream supply and processing chains that depend on the production of the broiler chicken for their continued functioning. I use archival, interview, and ethnographic data to detail the history of broiler farming, the emergence of contracting, and what the experience of it is like today. The most significant and novel part of this project is my ethnographic data collected over six months spent working on two broiler farms contracted with one of the largest firms in the US. To date, no other researchers have been able to gain this level of access. In this dissertation, I begin by exploring the role of management, detailing how the structure of the farming contract and ambiguous supervisory oversight facilitates farmer’s compliance with company demands. Then, utilizing agricultural and labor scholarship on deskilling in the labor process, I explore how poultry farming has become deskilled, robbing farmers of autonomy, the opportunity to agitate for better labor conditions, and ultimately eroding the intimate knowledge necessary to execute successful animal husbandry. Finally, I explore the games farmers play at work. While these games obscure how surplus value is appropriated from the farmer by the contracting firm, they also demonstrate farmer’s resistance and acquiescence to their deskilling and loss of autonomy.

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Christiansen, Alexandra R. "Nutritional, sensory, and quality attributes of heritage bred chicken and commercial broiler meat." Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/16284.

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Master of Science Department of Food Science Elizabeth A. Boyle Animal production factors can affect nutritional composition and quality of poultry meat. Quality attributes and fatty acid composition were evaluated on breast and thigh meat with skin from free range, heritage bred chickens (>116 day of age) (HB) and commercial broilers (<50 day of age) (CM). In addition, sensory and textural attributes were evaluated on breast and thigh meat of HB, and air or water chilled CM. Moisture and fat content was similar (P>0.05) between chicken types without skin. Thigh meat had at least 2.41% more fat (P<0.05) than breast meat; however, breast meat had at least 2.33% more moisture (P<0.05) regardless of skin inclusion or chicken type. Heritage meat with or without skin had a greater amount (P<0.05) of ω3 polyunsaturated fatty acids (PUFA) than CM regardless of chilling type and HB had a lower, more desirable ω6:ω3 ratio of 12.79 when compared to air or water chilled CM at 15.20 and 14.77, respectively. Heritage breast and thigh meat with skin contained 35.60 and 35.21% PUFA which was greater than (P<0.05) CM breast and thigh meat with skin at 20.96 and 20.45%, respectively. Whole carcass weight of CM, breast weight, and bone-in thigh weight was 71.30%, 148.0%, and 52.2% heavier (P<0.05), respectively, than HB weight. However, bone-in thigh yield was 2.1% higher (P<0.05) in HB. Commercial broiler breast and thigh meat was more tender (P<0.05) with higher myofibrillar tenderness and overall tenderness values and having less connective tissue than HB breast and thigh meat. Thigh meat from HB also had the highest (P<0.05) peak force values for Warner-Bratzler (3.47 kgf) and Allo-Kramer (7.22 kgf/g sample) shear tests. Thigh meat was perceived to be more juicy (P<0.05) and have more chicken flavor intensity (P<0.05) than breast meat. Heritage meat showed advantages in fatty acid profiles while CM meat showed advantages in yields and tenderness attributes.

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Mokgope, Precious Kgomotso. "Effect of dietry carrot meal supplementation on productivity and carcass characteristics of arbor acre broiler chickens." Thesis, University of Limpopo, Turfloop Campus, 2014. http://hdl.handle.net/10386/1103.

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Thesis (MA. Agric. (Animal Production)) -- University of Limpopo, 2014 This study determined the effect of carrot meal supplementation on productivity and carcass characteristics of Arbor acres broiler chickens aged one to six weeks. Experiment I determined the effect of carrot meal supplementation on productivity of Arbor acre broiler chicks aged one to 21 days. Two hundred unsexed Arbor acre broiler chickens were randomly assigned to five treatments with five replicates, each replicate having ten birds. A completely randomized design was used in the first experiment. The treatments were 0 (UA0), 20 (AU20), 50 (AU50), 75 (AU75) or 100 (AU100) g of carrot meal supplementation per kg DM feed. Quadratic equations were used to determine levels of carrot meal supplementation for optimal feed intake, metabolisable energy intake and nitrogen retention of Arbor acre broiler chickens aged one to 21 days. Linear equations were used to determine relationships between carrot meal supplementation and productivity variables. Dietary carrot meal supplementation had no (P>0.05) effect on growth rate, live weight and feed conversion ratio of unsexed Arbor acre broiler chickens aged one to 21 days. Carrot meal supplementation, however, improved (P<0.05) metabolisable energy intake and nitrogen retention of the chickens. Dietary metabolisable energy intake and nitrogen retention of the chickens were optimized at different carrot meal supplementation levels of 40.5 and 53.57 g/kg DM feed, respectively. No chicken deaths were recorded. Experiment II determined the effect of carrot meal supplementation on productivity and carcass characteristics of female Arbor acre broiler chickens aged 22 to 42 days. The chickens were randomly allocated to five treatments with five replicates, each having 10 birds, in a completely randomized design. The supplementation levels were 0 (FA0), 20 (FA20), 50 (FA50), 75 (FA75), or 100 (FA100) g of carrot meal per kg DM feed. Quadratic equations were used to determine levels of carrot meal supplementation for optimal feed intake, feed conversion ratio, live weight, metabolisable energy intake and nitrogen retention of broiler chickens aged 22 to 42 days. Linear equations were used to determine relationships between carrot meal supplementation and production variables. Dietary carrot meal supplementation had no (P>0.05) effect on growth rate, live weight and carcass parts of female Arbor acre broiler chickens aged 22 to 42 days. Carrot meal supplementation improved (P<0.05) feed intake, feed conversion ratio, metabolisable energy intake and nitrogen retention of Arbor acre broiler chickens aged vi 22 to 42 days. Dietary feed intake, feed conversion ratio, live weight, metabolisable energy intake and nitrogen retention were optimized at different dietary carrot meal supplementation levels of 52.8, 63.8, 38.0, 42.0 and 44.3 g/kg DM feed, respectively. Dietary carrot meal supplementation had no effect (P>0.05) on tenderness and flavour of female Arbor acre broiler meat. Broiler chickens on diets supplemented with 20, 50 or 100 g of carrot meal per kg DM feed produced meat with better (P<0.05) juiciness values than those of meat from chickens not supplemented with dietary carrot meal and those supplemented with 75 g/kg DM feed. There was a positive relationship between carrot meal supplementation and chicken meat juiciness. It is concluded that carrot meal supplementation improved (P<0.05) metabolisable energy intake and nitrogen retention of unsexed Arbor acre broiler chickens aged one to 21 days. However, carrot meal supplementation had no effect (P>0.05) on growth rate, live weight and feed conversion ratio of unsexed Arbor acre broiler chickens aged one to 21 days. Carrot meal supplementation improved (P<0.05) intake, feed conversion ratio, metabolisable energy and nitrogen retention of female Arbor acre broiler chickens aged 22 to 42 days. However, carrot meal supplementation did not (P>0.05) improve growth rate and live weights of the chickens.

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Humphrey, Brooke David. "Priority of the immune system for lysine, arginine and glucose in the broiler chicken /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2004. http://uclibs.org/PID/11984.

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Ekong, Olabisi Aderonke. "Profitability, farmer and farm characteristics: the case of Ghana broiler chicken industry in 2015." Thesis, Kansas State University, 2018. http://hdl.handle.net/2097/38610.

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Master of Science Department of Agricultural Economics Vincent R. Amanor-Boadu This study assessed the farm and farmer characteristics influencing the profitability of broiler chicken farms in Ghana. It used data obtained from the 2015 census of the poultry industry conducted by USAID-METSS in collaboration with Ghana's Ministry of Food and Agriculture and the Ghana National Association of Poultry Farmers. Results show that broiler production in Ghana is operated on a small scale basis with an average number of 1,410 birds. Broiler chicken production is profitable in Ghana with national average gross margin/bird of GHS 9.22 and standard deviation of 8.40. Regression analysis was carried out using Ordinary Least Square method to estimate the effect of farm and farmer characteristics on profitability and also explore regional differences. Results shows that farm income and feed were negative and statistically significant such that a farmer with primary income from broiler chicken production had a decrease in gross margin of GHS 1.24 per bird compared to a farmer with other sources of income; a farmer that increases one unit of own feed production will have a decrease in gross margin of GHS 0.06 per bird. Additionally, regional differences exist such that farms situated in Ashanti, Central, and Eastern had higher gross margin per bird of GHS 3.21, GHS 6.10 and GHS 6.26 respectively compared to farms situated in Brong Ahafo Region. In conclusion, the study shows that both farmer (primary source of income) and farm characteristics (such as regional location and the extent to which feed was prepared on the farm) were important in explaining broiler chicken profitability. Finally, continuous research is recommended to examine the robustness of these factors in explaining profitability.

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Menezes, Adriana Gomes de. "Identificação dos pontos criticos na produção avicola." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256960.

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Orientadores: Irenilza de Alencar Naas, Marta dos Santos Baracho Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola Made available in DSpace on 2018-08-14T11:27:11Z (GMT). No. of bitstreams: 1 Menezes_AdrianaGomesde_M.pdf: 3659236 bytes, checksum: 9ed106bcdf2c0254a5318139cf5e3141 (MD5) Previous issue date: 2009 Resumo: O presente trabalho propôs um estudo exploratório para determinar os pontos críticos de controle, gargalos e possíveis riscos do incubatório e da granja de produção de frango de corte. A pesquisa foi conduzida em um incubatório e em dois aviários na região do interior do Estado de São Paulo. O experimento foi conduzido nas seguintes salas do incubatório: sala de ovos, câmera fria, pré-aquecimento, incubadora e nascedouro. Os seguintes dados foram coletados no incubatório e nos aviários: dados de temperatura (T,?C) e umidade (UR,%), velocidade do ar (VA, m s-1), temperatura superficial do ovo e do pintinho (tS,?C), níveis de amônia (NH3) e luminosidade. Na avaliação dos aviários foi aplicado o questionário do manual de Boas Práticas de Produção de Frango de Corte, bem como entrevistas com os colaboradores/produtores e posterior aplicação da matriz de análise de risco para determinar os pontos críticos de controle. Após a coleta dos dados foi aplicado o Controle Estatístico do Processo (CEP), através da análise de Índice de Capacidade do Processo utilizando o software Minitab15®. Os pontos críticos identificados no incubatório e nas duas granjas analisadas foram a temperatura ambiente e umidade relativa. As categorias que se configuraram como pontos críticos de controle foram: cama de aviário, alimentação, água, higiene e saúde do trabalhador, manejo e biosseguridade, normas e legislações, instalações e planejamento das atividades. Pôde-se concluir que a análise dos PCCs associada às ferramentas de controle CEP, às diretrizes de boas práticas de produção e às demais literaturas consultadas, contribuíram para a garantia da segurança alimentar da produção avícola industrial, resultando em maior confiança na cadeia de produção. Abstract: This research presents an exploratory study to determine the critical control points, bottlenecks and possible risks of the incubation process and farm production of broilers. The research was conducted in an incubatory and two aviaries in the state of São Paulo. The experiment was conducted in the following rooms of the incubatory: egg room, cold camera, pre-heating and hatchery. The following data were collected in the incubatory and in the aviaries: temperature (T?C), humidity (% RH), air velocity (AV m s-1), surface temperature of the egg and the chick (ST), ammonia levels and light intensity. In the assessment of the aviaries, the following tools were applied: the questionnaire from the Manual of Good Practices for Broiler Production, interviews with employees/producers and subsequent application of the matrix of risk analysis to determine the critical control points. After collection of data, the Statistical Process Control (SPC) was applied, through the analysis of the Process Capability Index PCI and PC, using the software Minitab15®. The critical points identified in the incubatory and in the two farms were T(ºC) and RH(%). The topics that were taken into consideration as critical control points were: poultry litter, food, water, hygiene and health of workers, husbandry and biosecurity, legislation, facilities and planning of activities. It was observed that the analysis of PCCs associated with statistical control tools, guidelines of good practices for production as well as information from existing literature, contributed to ensuring the food safety of the poultry production industry, resulting in higher levels of trust in the production chain. Mestrado Construções Rurais e Ambiencia Mestre em Engenharia Agrícola

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Neves, Diego Pereira 1983. "Biomechanics of the feeding process of broiler chicks." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257099.

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Orientador: Irenilza de Alencar Nääs Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola Made available in DSpace on 2018-08-25T10:56:01Z (GMT). No. of bitstreams: 1 Neves_DiegoPereira_D.pdf: 2128104 bytes, checksum: aae1334cdaf344654741c087740bd7c6 (MD5) Previous issue date: 2014 Resumo: Os frangos podem exibir diferentes padrões de movimentos biomecânicos as partes do corpo em relação às características físicas do alimento (tamanho, formato e dureza) durante a alimentação. As limitações anatômicas relacionadas com a idade, sexo e linhagem também podem afetar o processo mecânico de alimentação. Para determinar a importância desses parâmetros, as medidas relacionadas aos movimentos biomecânicos de partes corporais são necessárias. Em particular, a trajetória, dimensões e efeitos temporais relacionados com o bico do frango e com a movimentação da cabeça devem ser considerados. No entanto, determinar esta informação manualmente do vídeo por um operador humano é tedioso e propenso a erros. A presente tese tem como objetivo avaliar o impacto de três tipos distintos de ração sobre a biomecânica da alimentação de frangos de corte. O total de 19 pintos de corte machos foram filmados durante a alimentação aos 3 e 4 dias de idade através de uma câmera de alta velocidade com taxa de aquisição de 250 fps (quadros por segundo). As rações avaliadas foram: farelada fina (F1), farelada grossa (F2) e quebrada (F3), no qual o diâmetro geométrico médio e o desvio padrão geométrico foram 476?m (2.54), 638?m (2.56), e 1243?m (2.43) , respectivamente. O peso e a morfometria do bico (comprimento e largura) foram medidos após as gravações. O deslocamento da cabeça das aves durante as fases `mouthful¿ e `mandibulação¿ e a abertura máxima do bico foram mensurados por de análise computacional de imagem. A fase `mouthful¿ consistiu no movimento da cabeça de forma ininterrupta direção oblíqua ou vertical em direção à ração até que a partícula de alimento fosse capturada. A fase `mandibulação¿ consistiu em um ciclo de abertura e de fechamento do bico, na qual existe uma abertura máxima do bico. Estas fases foram classificadas manualmente como: `mouthful¿ como 'sucedido' ou 'fracassado' e `mandibulações¿ como `catch-and-throw¿ (CT) ou `slide-and-glue¿ (SG). O `mouthful sucedido¿ consistiu quando a ave capturou o alimento com sucesso, e a `mouthful fracassado¿ quando a ave errou a partícula de alimento. `Catch-and-throw¿ consistiu no reposicionamento da partícula na ponta bico antes de iniciar o transporte para o interior da cavidade oral. `Slide-and-glue¿ consistiu na deslocação da língua até a ponta em bico para aderir as partículas de alimento com o auxílio da saliva pegajosa e transportar para o interior da cavidade oral. Os resultados indicaram correlações significativas de fraca intensidade entre o peso, as características morfométricas do bico e as variáveis biomecânicas, bem como correlação entre a abertura máxima do bico e o deslocamento cabeça. O deslocamento da cabeça foi maior no `mouthful sucedido¿ (0,439 mm ± 0,002) em relação ao `mouthful fracassado¿ (0,371 mm ± 0,005). Além disso, o deslocamento da cabeça foi mais expressivo em F3 (0,526 mm ± 0,005), F2 (0,519 mm ± 0,004) e F1 (0,431 mm ± 0,003), respectivamente. O deslocamento da cabeça também foi significativamente maior para CT (0,245 mm ± 0,001) do que SG (0,114 mm ± 0,000). Considerando os diferentes tipos de ração, o deslocamento da cabeça para CT foi maior em F3, F1 e F2, enquanto que para SG foram maiores em F3, F2 e F1, respectivamente. A abertura máxima do bico também foi maior para CT (0,245 mm ± 0,001) do que SG (0,114 mm ± 0,00). Além do mais, para CT foi maior no F3 e F1 que em F2, enquanto que para SG foi maior para F1, F3 e F2, respectivamente. Assim, os diferentes tamanhos das partículas de ração (granulometria) foi, potencialmente, o fator chave para o movimento dos pintos durante a alimentação. Além disso, esta relação não foi proporcional à granulometria, explicada por valores mais elevados em F3 e F1. A ocorrência de `mouthful fracassado¿ foi 18,0% para F3, 11,2% para F2 e 6,6% para a F1. Para a classificação das mandibulações, observou-se a maior frequência de CT em F3 (26,1%), F1 (24,9%) e F2 (17,9%), respectivamente. Esta situação sugere que os pintos capturaram as partículas na ponta bico de maneira mais adequada para a deglutição com a granulometria 638µm (F2) do que 476?m (F1) e 1243µm (F3), explicada pela menor movimentação e necessidade de reposicionamento das partículas de alimento. De forma geral, a tecnologia de câmeras de alta velocidade combinada com análise computacional de imagem adotada neste experimento foi um método eficaz para análise de movimentação. É desejável uma melhor compreensão das limitações mecânicas do aparelho bucal das aves durante a alimentação, a fim de determinar a relação entre os diferentes tipos de alimentos sobre os padrões biomecânicas exibidos pelas aves Abstract: Broiler chickens may exhibit different biomechanical motions patterns of the body parts in relation to the physical properties of feed (size, shape and hardness) while feeding. The anatomical limitations related to age, gender and breed may also impact the feeding mechanical process. To determine the significance of these parameters, measurements related to the biomechanical motions of body parts are required. In particular, the trajectory, dimensions and temporal effects related to the chicken¿s beak and head movements should be considered. However, determining this information manually from video by a human operator is tedious and prone to errors. The present thesis aims assess the impact of three different feed types on the biomechanics of feeding behaviour of broiler chicks. A total of 19 male broiler chicks were recorded while feeding at 3 and 4-d-old using a high-speed camera with an acquisition rate of 250 fps (frames per second). The feed types considered were: fine mash (F1), coarse mash (F2) and crumbled (F3), in which the geometric mean diameter and the geometric standard deviation were 476µm (2.54), 638µm (2.56), and 1243µm (2.43), respectively. The birds¿ weight and morphometric traits of the beak (length and width) were measured after the recordings. The birds¿ head displacement during mouthful and mandibulation phases and the maximum beak gape were measured through computational image analysis. Mouthful phase consisted an uninterruptedly head movement towards feed in an oblique or vertical direction until the feed particle is grasped. Mandibulation phase consisted in one cycle of opening and closing of the beak, in which there is a maximum beak gape. These phases were manually classified, as follows: mouthfuls as `normal¿ or `fail¿ and mandibulations as catch-and-throw (CT) or slide-and-glue (SG). Normal mouthful was when the bird successfully grasped the feed, and fail mouthful was when the birds missed the feed. Catch-and-throw is when the feed is repositioned within the beak tip before starting the transport into the oral cavity. Slide-and-glue consists in the displacement of the tongue up to the beak tip in order to glue the feed particles with the aid of the sticky saliva and carry inward oral cavity. The results indicated significant correlations of weak intensity between weight, morphometric traits of the beak, and the biomechanical variables, as well as correlation between maximum beak gape and head displacement. The head displacement was higher in a normal mouthful (0.439 mm ± 0.002) than fail mouthful (0.371 mm ± 0.005). Furthermore, head displacement was more expressive in F3 (0.526 mm ± 0.005), F2 (0.519 mm ± 0.004), and F1 (0.431 mm ± 0.003), respectively. The head displacement was also significantly higher for CT technique (0.245 mm ± 0.001) than SG (0.114 mm ± 0.000). Considering the different feed types, head displacement for CT was higher in F3, F1 and F2, while for SG were higher in F3, F2, and F1, respectively. The maximum beak gape was also higher for CT (0.245 mm ±0.001) than SG (0.114 mm ± 0.00). Moreover, for CT it was higher in F3 and F1 than in F2, while for SG was higher for F1, F3 and F2, respectively. Thus, the different size of the feed particles (granulometry) was potentially the key factor for the chicks¿ motion while feeding. Besides, this relation was not proportional to the granulometry, explained by higher values for F3 and F1. The occurrence of `fail mouthful¿ was 18,0% for F3, 11,2% for F2 and 6,6% for F1, respectively. For mandibulations classification, it was observed a higher frequency of CT in F3 (26,1%), F1 (24,9%), and F2 (17,9%). This situation suggests that the chicks grasped the particles in the beak tip more properly for swallowing with the granulometry 638µm (F2) than 476µm (F1), and 1243µm (F3), explained by the less motion and necessity of repositioning the feed particles. Overall, the high-speed camera technology combined with computational image analysis adopted in this experiment was an effective method for motion analysis. It is desirable a better understanding of the mechanical limitations of the birds¿ jaw apparatus while feeding in order to determine the relationship between different types of feed in biomechanical patterns displayed by the birds Doutorado Construções Rurais e Ambiencia Doutor em Engenharia Agrícola

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Jezile, G., D. Westfall, G. Peterson, DR Child, DP Turner, and Averbeke W. Van. "Effects of liming on microbial activity and N mineralization in broiler manure-amended soils from Bizana, Eastern Cape, South Africa." Taylor & Francis, 2008. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001059.

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A laboratory incubation study was conducted to determine the effects of liming on microbial activity and N mineralization in two Bizana soils amended with broiler manure. The experimental layout was a 4 x 3 complete factorial experiment with three replicates, arranged in a randomized design. Soil pH, CO2 evolution, and mineral N concentration were measured. After 56 days the soil pH ranged from 4.50 to 5.74 and 4.99 to 5.94, in the Magusheni and Nikwe soils, respectively. The effect of liming on microbial activity and N mineralization differed between the soils. In the Nikwe soil (acid saturation 4.0%), microbial activity and N mineralization increased as the rate of broiler manure application was raised, but liming had no effect. In the Magusheni soil (acid saturation 25%), microbial activity increased as both lime and chicken manure application rates increased, but liming reduced N mineralization, suggesting N immobilization was being driven by an active microbial population in the limed soils. The rates of lime and/or chicken manure application, percentage Ca2+ and soil acid saturation were important factors influencing microbial activity and N mineralization, but the effect of soil pH on N mineralization was not evident in either of the soils.

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Ferreira, Petrus Stephanus. "A management model for service excellence and organisational performance in the breeder/broiler chicken industry." Thesis, Bloemfontein : Central University of Technology, Free State, 2008. http://hdl.handle.net/11462/98.

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Thesis (D. Tech)--Central University of Technology, Free State, 2008 The global, one-world economy has arrived and South Africa is part of it. Business needs to understand the challenge of global competitiveness. This study reflected the prominence of managing diversity in establishing service excellence and performance management for professionals in the mediumsize chicken breeder/broiler industry in South Africa, following the increased importance of the breeder/broiler industry in providing an affordable nutriment/commodity to the poor and needy South African population. The ongoing variables in the political, social, cultural and technology domains in South Africa also affect the chicken breeder/broiler industry. It necessitates the scientific evaluation of the effect of the external political and socio-political environment; internal training and development, leadership styles, literacy levels, employment equity, resistance to change, reverse discrimination and cultural diversity on service excellence and performance. Country Bird (Pty) Ltd., a significant role-player in the food production industry, was thus selected as the object of this study. The role of management and the workers was examined to determine the level of impact in attaining service excellence and organisational performance. Attention was also focused on the development of a service excellence and organisational performance management model that can be used in the chicken breeder/broiler industry to improve organisational performance and sustainable profits.

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Calais, Andreas. "Poor welfare or future investment? Different growth pattern of broiler breeders." Thesis, Linköpings universitet, Biologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-118552.

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The parental stock of meat type chickens (broiler breeders) are commonly feed restricted to decrease their rapid growth and the issues associated with it. Among these birds, chronic hunger and stress are the most prominent welfare concerns and mass heterogeneity within flocks a major management challenge. The present study compared small and large broiler breeders of the same age within a flock, with the hypothesis that small birds would show signs of poorer welfare indicated by higher corticosterone concentration and heterophil/lymphocyte ratio as a consequence of higher experienced feed restriction due to competition. It also aimed to characterize morphometric differences between small and large birds within flocks as well as between birds on different feeding regimens; skip-a-day vs. every-day-fed. Heterophil/lymphocyte ratio at 4 weeks was significantly higher in large birds compared to small birds, but corticosterone concentration did not differ. Relative mass of the upper gastrointestinal tract, pancreas and liver of small birds at 4 weeks of age were significantly larger, while relative muscle and gizzard fat mass were significantly lower compared to large birds. 12 weeks old skip-a-day fed birds largely followed the pattern of 4 weeks old small birds. In the present study, no clear signs of poorer welfare in small broiler breeders could be seen and the morphometric differences might suggest different ways to cope with feed competition. A larger gastrointestinal tract might indicate long-term investments and maybe that smaller broiler breeders, and skip-a-day fed birds, are better habituated to feed restriction.

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Radebe, Nomvula Emily. "Utilization of whole hatchery waste meal as alternative feedstuff in broiler diets." Thesis, [Bloemfontein?] : Central University of Technology, Free State, 2012. http://hdl.handle.net/11462/168.

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Thesis (M. Tech.(Agriculture: Animal Production)) - Central University of technology, Free State, 2012 A 42-day feeding trial involving 180 day old broiler chicks was carried out at Glen Agric Institute ARC poultry section to study the effects of whole hatchery waste meal (WHWM) as an alternative in broiler diets. In this study whole hatchery waste meal (WHHW) replaced fish meal (FM), protein for protein, in broiler diets at 0, 10, 20, and 30% levels. One hundred and eighty broiler chickens were grouped, 45 birds per treatment which were further replicated 3 times (15 birds per replicate) in a completely randomized design. Feed and water supply were offered to birds ad libitum while standard management practices were meticulously adopted. Samples of the two test ingredients were sent to a lab for chemical analysis and the results indicated that FM had higher content of crude protein (73.18%) while that of WHWM was 4226. The calcium phosphorus ratio was 16.6:1 for WHWM as against 1.5:1 in the FM. The results also indicated a higher content of Ash% and Ether extract for WHWM (18.12) and (23.94) respectively. The higher ash content could be due to the high content of eggshell at the time of processing. At the end of the feeding trial broiler performance, blood, carcass characteristics and the economic benefit of using WHWM in broiler diets were determined. Blood and meat samples were collected and sent to the pathology laboratory at the University of the Free State, Bloemfontein for hematological and meat characteristics analysis. Results for broiler performance showed that broilers fed diet 2 had highest values for feed intake (118.25g/bird/day), weight gain (50.16g/bird/day) and daily protein intake (29.08g/bird/day) while those fed with diet 3 were superior in the efficiency of feed conversion (2.31). The highest value of abdominal fat 1.12% was observed in birds fed diet 2. The highest live mass was observed in birds fed diets containing no WHWM (2.83), while non significant difference were observed in live mass of birds fed diet 1, 3 and 4. Broilers fed control diet had highest mean values for eviscerated weight (2.20kg) and dressing percentage (77.86%). Blood samples were sent for analysis of White blood cells (WBC), Red blood cells (RBC) and Haemoglobin (HGB), Hematogrit (HCT), Mean corpuscular volume (MCV), Mean corpuscular haemoglobin (MCH) and Mean corpuscular haemoglobin concentration (MCHC). The results showed marginal variations in blood parameters. White blood cell counts were higher for birds fed control diet (519.59 x 103/1) than those fed WHWM (484.93 X 103/1). Non significant differences (P > 0.05) were observed on the HGB of all treatment groups including the control group. RBC counts of T1-T3 were not significantly different from each other but statistically significantly different from T4 (30% WHWM). The highest value of 2.67 106/ mm3 was observed in birds fed a higher level of WHWM. High RBC and HGB counts in the birds fed WHWM are an indicative of higher oxygen carrying capacity. The HCT and MCH results showed nonsignificant differences between T1, T3 and T4, except T2 which was significantly different from the other treatment groups. The MCV values for T1-T4 were 132.58, 126.47, 129.15 and 128.15 10'15L respectively. The highest and lowest values were recorded on T1 and T2 respectively. The feed costs decreased with an increase in the level of WHWM in broiler diets. The lowest feed cost/kg weight gain of R8.69 recorded for broilers fed on diet three. This agrees with several studies which documented the use of hatching waste in poultry diet as means of reducing feed cost (Babiker et al 1991; Abiola, 1999; Abiola, 2000; Abiola and Onunkwor 2004). It can be concluded that 10% of FM can be replaced with WHWM in broiler diets without adverse effects on growth, hematological and carcass traits.

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Fatoumata, Diarrassouba. "Impacts of antimicrobial growth promoters used in broiler chicken production on the emergence of antibiotic resistance in commensal E. coli and Salmonella." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/1614.

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Despite their beneficial effects, concerns have been raised about the role of antimicrobial growth promoters (AGP) in the emergence of antibiotic resistant bacteria. This study evaluated the effects of approved AGP on the emergence of antibiotic resistance in commensal E. coli and foodborne pathogen Salmonella. A survey of antibiotic resistance levels in commercial broiler chicken farms in the Fraser Valley (B.C.) and an experimental feeding trial were conducted from May 2004 to February 2005 and May to November 2005, respectively. The latter examined the effects of ten AGP formulations (bambermycin, penicillin, salinomycin, bacitracin, combination of salinomycin and bacitracin, chlortetracycline, virginiamycin 11ppm, virginiamycin 22ppm, monensin and narasin) on bird performance as well. Multiple antibiotic resistant commensal E. coli and Salmonella carrying virulence genes were found at commercial broiler chicken farms and therefore may serve as reservoirs for these genes. There was no significant difference between feed formulations on the phenotypic or genotypic characteristics of the isolates, except for tetracycline resistance gene tet(B). In the experimental feeding trial, broiler chickens were fed a diet including or excluding AGP. Birds were sampled prior to and weekly during feeding of the control and the AGPP containing diets. Although not detected on day 0, E. coli increased after day 7 to more than 9.9 log10 CFU/g in ceca. Multi-drug resistant E. coli were isolated from birds fed the ten AGP containing diets as well as the control diet. Except for penicillin, none of the AGP containing diets significantly improved bird performance compared to the control diet (P>0.05). Good management practices can significantly improve broiler chickens performance and decrease the mortality rate.

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35

Duggan, Brendan Michael. "Genetic improvement of skeletal architecture and locomotion in domestic poultry." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31096.

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Breeding success in the broiler chicken has been accompanied by gait problems which are detrimental to productivity and welfare. Although these gait issues have not been reported to the same extent in Pekin ducks, there is concern that such problems will manifest if the duck continues on its current selection trajectory. In order to understand how changes in morphology due to selection have affected gait in both species, divergent lines were objectively assessed for gait using a pressure platform (12 birds per line at three, five and seven weeks of age). The broiler chicken was compared to the slower growing layer chicken and the Pekin duck to its slower growing ancestor, the mallard. Two breeding lines of Pekin duck were also assessed. After gait assessment, the leg bones (femur and tibiotarsus) were scanned by computed tomography to measure morphological changes which have occurred due to selection for high growth and meat yield. Results were analysed by ANOVA, accounting for age and sex. During walking, heavy lines walked at a slower velocity, displayed a wider stance and spent more time supporting their mass on both feet than their lighter conspecifics, strategies which are likely to improve balance. The foot angle while walking differed between lines; all duck lines rotated their feet internally whereas the layer chickens’ feet were aligned with the direction of travel. Conversely the broiler chicken rotated its feet externally by seven weeks of age. Morphologically, the main differences were between species. Duck lines reached adult leg size earlier than chickens, which may be a response to differing adaptive environments prior to domestication. This early cessation of bone growth in ducks may provide more opportunity for the bones to remodel to handle the loads imposed on them. Lower levels of porosity and a unique cortical architecture observed in ducks endow relatively greater bone strength. Bone curvature also differed between species; the tibiotarsus curved more laterally in ducks than in chickens and may be a swimming adaptation that hinders locomotion on land in the modern production bird. In order to improve the objectivity of selection for better gait in poultry, the genetic parameters of gait components selected on the basis of results in this thesis were estimated using a linear mixed model in a population of Pekin ducks of known pedigree. As they are a simpler measure, similar or improved heritability estimates were estimated for these gait components when compared with the standard commercial gait score which is based on a subjective view of walking ability. Intense selection for economic traits has altered gait in similar ways in both species. To improve gait in poultry, greater breeding success may be achieved by focussing on those components of gait which have changed through selection, rather than using a subjective overall visual gait score. Furthermore, in both species, adaptations for pre-domesticated life may have affected the ability with which the selected lines have accommodated their gait to other morphological changes associated with increasing body mass.

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Nelson, Laura Ashley. "Dietary macronutrient composition and exogenous neuropeptide Y affect feed intake in brioler chicks." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/48899.

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Understanding the central nervous systems role in appetite regulation is crucial to cure the obesity epidemic, which is more prevalent than any disease in the United States. Central appetite regulators, known as neuropeptides, are pivotal in understanding appetite regulation. Neuropeptide Y (NPY), a 36 amino acid peptide, plays a major role in regulating the hunger signals from the brain. In all vertebrates studied, it is a strong orexigenic neurotransmitter located throughout multiple nuclei of the hypothalamus. Peripheral hormones associated with hunger are able to activate NPY neurons in the arcuate nucleus, which leads to a cascade of events that activate orexigenic neurons throughout the hypothalamus. Although extensive research has gone into understanding the role of NPY in appetite regulation, the effects of macronutrient composition of diets on NPY function have not been elucidated in non-mammalian species. This research investigates how food intake is affected by dietary macronutrient composition in broiler type chickens that are fed three varying macronutrient diets: high carbohydrate (22% CP, 3000kcal/kg) a broiler starter diet, high fat (60% ME from lard), high protein 30%CP). All diets were formulated to be isocaloric. When chicks are fed the high fat diet central NPY administration has a greater effect on feed intake compared to both the basal and high protein diet. Regardless of what diet the chick is fed from hatch, if they are switched to one of the other two diets post central administration of NPY the high fat diet stimulated feed intake for the longest duration. Although, NPY had the strongest orexigenic effect on chicks fed the high fat diet, in a choice diet situation broiler chicks chose the high protein diet, independent of central NPY administration. Master of Science

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Cox, Chasity Marie. "The effects of dietary β-glucan supplementation on performance and immune response of broiler chicks during an Eimeria challenge". Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/46327.

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Escalating consumer concerns have placed the poultry industry under mounting pressure to reduce the use of chemotherapeutic agents as feed additives. One possible alternative receiving increased attention is the use of immunomodulators such as β-glucan. A pilot study evaluated the effects of a yeast derived β-glucan (Auxoferm YGT) on growth performance and immune response of broiler chickens. Day-old chicks were fed a diet containing 0, 0.02, or 0.1% yeast β-glucan. On days 7 and 14 post-hatch, body weight and relative immune organ weights were measured, peripheral blood was collected to determine heterophil to lymphocyte (H:L) ratios, and small intestinal sections were sampled to evaluate relative gene expression. The addition of β-glucan had no influence on growth. Dietary β-glucan supplementation modulated the expression of interleukin (IL)-8, IL-18, interferon (IFN)-γ and inducible nitric oxide synthase (iNOS) in the small intestine. A subsequent study was conducted to investigate the effects of dietary β-glucan on broiler chick (1440 birds) performance and immune response during a mixed Eimeria infection (day 8 of age). Measurements were taken and samples collected on days 4, 7, 10, 14 and 21 post-hatch. The results from this study show that β-glucan supplementation did not negatively impact performance. The addition of β-glucan to the diet resulted in reduced gross lesion severity and increased H:L ratios. The gene expression results suggest that β-glucans are capable of skewing the host immune response toward aTh1 mediated response and consequently down-regulating the Th2 mediated response. Master of Science

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38

Hakansson, Franziska. "Effect of daytime and age on the avoidance and approach behaviour of commercial Danish broiler chicken." Thesis, Linköpings universitet, Biologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-119347.

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As activity levels of intensively managed broiler chicken vary over time, detailed knowledge on their influence is potentially useful to further adjust welfare assessment schemes. Therefore, this study investigated the influence of daytime and age on the performance of broiler chicken in two applied fear tests.On-farm studies were carried out in 14 flocks of intensively managed broiler chicken. A forced and a voluntary approach test were conducted during morning and evening hours and at three different ages (1: 6-12d; 2: 21-24d; 3: prior to slaughter). At each observation, avoidance distances (AD) and the number of animals voluntarily approaching (VA) an observer were collected.No significant correlation was found between daytime and AD or VA. When tested at different ages, daytime and VA were significantly correlated (1: r= 0.56*; 2: r= 0.40*; 3: r= 0.64*), but the results were not consistent. At three weeks the VA was found to be higher in the morning but at younger age and prior to slaughter, more birds approach an observer in the evening. Both, approach and avoidance peaked at three weeks and decreased prior to slaughter. Further, the effect of differing observer locations in the chicken house on the behavioural response of broiler chicken was studied. A higher proportion of birds voluntarily approached an unknown human in the area close to the main entrance door, but the avoidance behaviour was not affected.From the results of this study I conclude, that the time of assessment has no effect on avoidance or approach behaviour of commercial slow-growing broiler chicken. However, fear related behaviour changed depending on age. This makes the applied tests potentially applicable independent of daytime restrictions when performed with birds of the same age.

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Sabbagh, Rian Saleh. "Asymmetry in growth of the broiler chicken : histochemical and anatomical studies on the musculo-skeletal system." Thesis, Durham University, 1990. http://etheses.dur.ac.uk/6251/.

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The aim of this work was to study the apparent asymmetry in the breast muscles in some individual broiler chickens strain "Cobb 500", with a view to revealing the cause(s) of this asymmetrical growth. Birds showing apparent asymmetry in the breast were selected to study their breast muscles anatomically and histochemically in comparison with unselected birds as controls. The skeleton was studied in these birds too. Selected chickens had heavier body and muscle weight, and higher growth rate than the controls. However, no significant differences were obtained between the two sides of the pectoralis or supracoracoideus muscles in either group of chickens, although the degree of asymmetry of the pectoralis muscle in selected chickens was higher than in the controls. The distribution of pectoralis muscle weight (degree of asymmetry) was normally distributed in both groups of chickens. The histochemical study on the pectoralis muscle revealed that there were significant differences in fibre number and diameter between the anterior (region A) and mid part (region B) of the pectoralis muscle in both groups of chickens, in that there were more FG fibres in region B, whereas region A has more FOG and SO fibre number. The diameter of fibre type in region A was significantly larger than in region B. Differences in fibre diameters were obtained between the right and left side of the pectoralis muscle. FG and SO fibres in the left anterior side of pectoralis muscle were growing significantly faster than in the right side in selected chickens, and control (against body weight or muscle weight). However, no significant differences were obtained for fibre numbers per square millimeter either between the two sides in control or in selected chickens. Many measurements on the skeleton were taken to study the shape of the sternum and the rib-cage in both groups of chickens. The essential differences were the depth of the keel, shape of the rib-cage, and the shape of the ribs. In selected chickens, depth of the keel at the right side was significantly deeper than the left, consequently the width and height of the keel in the left side were significantly greater than in the right side. As a result, the breast angle at the right side was significantly larger than the left one. Statistical analysis revealed significant differences in the shape of the ribs between the two sides. Ribs at the left side had significantly greater: arc and chord length, enclosed area and height; than the right side. In addition the orientation dorsal angle of the left ribs was significantly greater than the right. As a result, selected birds had faster bone growth, shorter, and less bone weight than the controls, in addition to the deformities in the shape of the keel, rib-cage, and ribs. From the results, it would appear that the asymmetry in the shape of the keel and rib-cage could be the consequence of the high growth rate in body weight and increased breast muscle weight, without increase of the growth of skeletal mass. Such disproportionate change in body parts could be the result of direct selection for increased amount of breast muscles. This problem could be reduced by restriction of early growth and include the concept of the skeletal growth in the selection-programme indices.

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Williams, Ischer Sarah Ashlee. "Evaluation of a sprinkler cooling system on inhalable dust and ammonia concentrations in broiler chicken production." Thesis, University of Iowa, 2016. https://ir.uiowa.edu/etd/3216.

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Indoor air contaminants such as dust and gases are present in concentrations that may be hazardous to worker health in poultry production. Poultry dust may contain inflammatory agents (e.g., endotoxin) and inhalation exposure has been associated with pulmonary symptoms. The current control practice to reduce worker exposure to poultry dust is the use of respiratory protection (e.g., filtering face-piece respirators). Limited research has been conducted to evaluate engineering controls to reduce dust concentrations in broiler chicken production. Therefore, the purpose of this research was to evaluate the effectiveness of a water sprinkling system to reduce inhalable dust and ammonia concentrations in a broiler chicken house. Inhalable dust and ammonia concentrations were measured daily for the production cycle of a flock of broiler chickens (63 days). Inhalable dust was measured gravimetrically using an inhalable sampler and ammonia was measured by a direct reading sensor. Sampling was performed on a stationary mannequin inside two broiler chicken houses. One house used a sprinkler cooling system to deliver a water mist throughout the house and the second house was an untreated control. The sprinkler system activated 5 days after chicken placement and continued through day 63 of the broiler chicken production cycle. The following sprinkler activation program was used each hour from 6am to 10pm: days 5 – 9 five seconds, days 10 – 14 ten seconds, and days 15-63 for fifteen seconds. Geometric mean (GM) inhalable dust concentrations collected in the treatment house (5.2 mg/m3) were lower than those found in the control house (6.0 mg/m3). The GM ammonia concentration within the treatment house was higher at 10.6 ppm (GSD: 1.80), compared to the control house (GM 9.51 ppm; GSD: 1.77). However, the observed differences were not statistically significant (p = 0.33 and p = 0.34, respectively). Concentrations of inhalable dust were reduced by 11β when using the water sprinkling system, however the reduction was not statistically significant. The observed reduction in dust concentration was not sufficient to eliminate the need for respiratory protection.

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Borges, Vívian Palmeira. "Principais lesões macro e microscópicas em frangos de corte condenados por caquexia em abatedouro : contribuição ao diagnóstico /." Jaboticabal : [s.n.], 2006. http://hdl.handle.net/11449/95981.

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Orientador: Oswaldo Durival Rossi Júnior Banca: Antonio Carlos Alessi Banca: Eurípedes Batista Guimarães Resumo: A caquexia figura como uma das mais importantes causas de condenação total de frangos de corte durante a inspeção em abatedouros frigoríficos determinando grandes prejuízos ao setor avícola. Para melhor entender esta enfermidade foram estudados os aspectos macro e microscópicos de 400 aves caquéticas de um abatedouro frigorífico sob Inspeção Federal no Estado de Mato Grosso do Sul. Foram relatadas e catalogadas todas as lesões macro e microscópicas das aves caquéticas examinadas. Devido às diferentes alterações detectadas e aos diversos órgãos atingidos pôde-se concluir que as etiologias devem ser variadas. O fígado, sacos aéreos e pele foram os órgãos mais comumente comprometidos. O envolvimento do fígado, em vários graus e com lesões diferenciadas, em grande parcela dos casos induziu à percepção de que o comprometimento deste órgão - importante para a síntese protéica - está intimamente relacionado ao aparecimento de quadros de caquexia. A lesão de degeneração da cabeça femoral, embora não tenha sido uma alteração freqüentemente detectada têm correlação positiva com o aparecimento de casos de nefrite caseosa. O índice de aparecimento de lesões teciduais maior nos animais caquéticos que naqueles não caquéticos e o fato de que períodos curtos de privação alimentar não interferem no aparecimento de graus mais severos de caquexia são dados que corroboram para o entendimento de que esta é uma síndrome associada a enfermidades e não à fome. Abstract: Cachexia is one of the most important causes of carcass downgrading in poultry inspection and it determines serious losses to poultry industry. To better understand this syndrome, the macro and microscopic aspects of 400 cachetic carcasses were studied in a slaughterhouse under Federal inspection in Mato Grosso do Sul State. Each macro and microscopic lesion was reported and classified. Because of the several alterations in many viscera it was possible to conclude that there must be a plenty of etiologies. Liver, air sacs and skin were the most compromised organs. Hepatic involvement in different levels induce to the perception that this important organ in protein synthesis is close related to cachexia cases. Femoral head degeneration although not frequently identified showed a positive correlation to caseous nephritis. Ali the studied lesions were greater in cachetic animais when compared to non-caquetic broilers. This data associated to the fact that short periods of time of food deprivation do not interfere in severe cases of cachexia corroborate to the understanding that this is a syndrome related to diseases and not to hunger. Mestre

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Machethe, Tanya Ashley. "Economic and marketing analysis of smallholder broiler production in Mopani District of Limpopo Province, South Africa." Thesis, University of Limpopo, 2016. http://hdl.handle.net/10386/1724.

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Thesis (MSc. (Agricultural Economics)) -- University of Limpopo, 2016 The broiler industry in South Africa consists of both small-scale and commercial poultry farmers. It provides the cheapest source of protein, absorbs labour and contributes massively to the agricultural sector. Broiler industry absorbs labour from the labour market, both skilled and unskilled; therefore it is a good source of employment. The specific objectives of the study included determining factors influencing productivity among smallholder broiler producers in Mopani District using Stochastic Frontier Production Function and technical efficiency analysis. The profitability of smallholder broiler production in the study area was also estimated using the Gross Margin Analysis. Furthermore, determinants of market participation among smallholder broiler producers in the study area were analysed using the Logit model. The Stochastic Frontier Production Function results revealed a positive relationship between the productivity of the farmers in their broiler production and labour, feeds, stock size and vaccines. The results also showed that feeds was significant at 1% while stock size was significant at 10% level. The technical efficiency results indicated that smallholder broiler farmers in Mopani District could save an average of 23.4 % in production costs and realize a maximum cost saving of 95.8% in production costs. The Gross Margin Analysis revealed that the cost of feeds were the highest incurred, taking up 70.61% of the total costs of production and the second highest being cost of stock comprising of 15.11% of the total production costs. The Logit results on the determinants of market participation showed that household size, income received per month, experience, land size, access to market information, distance to the market, profitability and land ownership are statistically significant in determining participation in the market. Based on the findings from the study, it is recommended that linkages between the formal markets and the smallholder farmers be established for farmers not participating in the market. Farmers who making profit and have more experience in broiler production should be provided with a platform to grow into commercial farming. This could be through subsidies or provision of other incentives that are key to enhancing expansion, such as land and funds.

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Cross, Deborah Elaine. "Phytochemical and enzyme supplementation of broiler chicken diets and the effects on intestinal microflora, nutrient utilisation and performance." Thesis, University of Glasgow, 2004. http://theses.gla.ac.uk/4867/.

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Zhang, Shuai. "Physiological and Biochemical Aspects of Methionine Isomers and Precursors in Broilers." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/71816.

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Methionine (Met) is an essential amino acid for animals and also the first limiting amino acid in a broiler diet. The dietary supplemental Met sources include the natural isoform L-methionine (L-Met), the synthetic form DL-methionine (DL-Met) and the synthetic Met precursor DL-2-hydroxy-4 (methylthio)-butanoic acid (DL-HMTBA). The objective of this dissertation was to determine the effect of different dietary Met source supplementation and Met deficiency on a series of physiological and biochemical aspects, including growth performance, global DNA methylation and methyltransferase activity, blood antioxidant profile (e.g., acute phase protein, leukocyte count), intestinal nutrient transporter gene expression, Met converting enzyme gene expression and activity, oxidative stress markers, and a potential pathway related to amino acid signaling. To achieve this goal, male Cobb-500 broilers were raised from day of hatch (d0) to d35 post-hatch and fed a diet deficient in methionine and cysteine (Met + Cys) (control) or the same diet supplemented with 0.22% DL-Met, 0.22% L-Met or 0.31% DL-HMTBA (to provide 0.22% DL-Met equivalent) to meet Met + Cys requirements. Tissues (liver, breast muscle, duodenum, jejunum and ileum) and blood samples were collected at various ages from d0 to d35 for analysis. Met supplementation significantly improved body weight gain and feed efficiency compared to the Met deficient group, but no differences were observed among DL-Met, L-Met and DL-HMTBA for growth performance parameters (P > 0.05). Met supplementation had no effect on red blood cell packed cell volume, white blood cell differential count, hepatic total DNA methylation, DNA methyltransferase and Met oxidase activity, and had limited effects on activation of p70S6K, a key amino acid signaling protein (P > 0.05). Although dietary Met sources did not change oxidative status of the treated chickens, both L-Met and DL-Met but not DL-HMTBA supplementation decreased the level of acute phase protein serum amyloid A compared to the control group (P > 0.05). The effect of Met supplementation on gene expression of nutrient transporters and Met converting enzymes were complex and dynamic. Most of the target genes demonstrated tissue- and development-dependent expression patterns, with few significant treatment effects observed. L-Met and DL-Met but not DL-HMTBA supplementation enhanced the neutral amino acid transporters ATB0,+ and B0AT gene expression in various small intestinal segments. All three Met sources increased monocarboxylic acid transporter (MCT1) gene expression in the jejunum. DL-HMTBA and L-Met fed chickens showed greater hepatic L-HMTBA oxidase (HAO1) gene expression. DL-Met increased glutamic-oxaloacetic transaminase 2 (GOT2) gene expression in the duodenum. An in vitro study with tissue explants, however, did not demonstrate a similar gene expression pattern as that in the in vivo study. Lastly, RNA sequencing results illustrated that Met deficiency could lead to many differentially expressed genes but different supplemental Met sources had no influence on hepatic gene expression profiles. In conclusion, as common dietary supplemental Met sources, L-Met, DL-Met and DL-HMTBA exhibited similarity in impacting intestinal amino acid/peptide/monocarboxylic acid transporter gene expression and Met converting enzyme activity. The regulatory roles of Met as an antioxidant and nutrient signaling in cell metabolism were not affected by different dietary supplemental Met sources. Ph. D.

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Fiorentino, Nicole Marie. "Assessment of iron bioavailability and protein quality of new fortified blended foods in broiler chickens." Thesis, Kansas State University, 2017. http://hdl.handle.net/2097/35497.

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Master of Science Department of Food, Nutrition, Dietetics, and Health Brian L. Lindshield Fortified-blended foods (FBFs), grain-legume porridges (most commonly corn and soy), are frequently used for food aid purposes. Sorghum and cowpea have been suggested as alternative FBF commodities because they are drought-tolerant, grown locally in food aid receiving countries, and are not genetically modified. The objective of this thesis was to determine the protein quality and iron bioavailability of newly formulated, extruded FBFs in broiler chickens, which have been suggested as a good model for assessing iron bioavailability. Five FBFs were formulated to contain whey or soy protein to compare protein quality, sugar, oil, and an improved micronutrient premix. These included three white sorghum-cowpea FBFs; two were extruded with either whey protein concentrate (WSC) or soy protein isolate (WSC+SPI) added, one was non-extruded (N-WSC). Two others were white sorghum-soy (WSS) and corn-soy (CSB14) FBFs. Two additional white-sorghum cowpea FBFs were reformulated and “over-processed” to contain no sugar, less whey (O-WSC) or soy protein (O-WSC+SPI), and less oil, thus producing a less expensive FBF. Two studies were performed using prepared (Prep) or dry (Dry) FBFs, along with the United States Agency for International Development (USAID) corn and soy blend FBF, CSB+, fed to chickens for 3 and 2 weeks, respectively; food intake, body weights, hemoglobin, and hepatic iron were assessed. In the Prep study, new FBFs significantly increased caloric and protein efficiency compared to CSB+, despite similar food intake and body weight gain. In the Dry study, CSB+ significantly decreased food intake and caloric efficiency, with the exception of O-WSC+SPI, and nonsignificantly reduced body weight gain and protein efficiency compared to new FBFs. CSB+ significantly reduced hepatic iron content compared to all FBFs in the Dry study, and was nonsignificantly decreased compared to new FBFs in the Prep study. In conclusion, sorghum and cowpea FBFs performed similarly to corn and soy FBFs, suggesting these commodities are suitable replacements for corn and soy. Soy protein isolate (WSC+SPI) was an effective alternative to whey protein concentrate (WSC), suggesting SPI can be a less expensive protein supplement in FBFs. Surprisingly, non-extruded sorghum and cowpea (N-WSC) was equally efficacious to extruded WSC. However, N-WSC did not meet viscosity requirements and is not precooked, which limits its viability as an FBF. O-WSC+SPI resulted in poorer outcomes compared to other FBFs, which suggests the protein quality of cowpea may be inferior and the inclusion of whey protein is needed in this formulation, as O-WSC with whey performed similarly to other FBFs. Overall, new FBFs, with the exception of O-WSC+SPI, resulted in improved food efficiency and hepatic iron outcomes compared to CSB+, suggesting they are of higher nutritional quality. However, further research is needed to refine and identify the best FBF formulations.

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46

Borges, Vívian Palmeira [UNESP]. "Principais lesões macro e microscópicas em frangos de corte condenados por caquexia em abatedouro: contribuição ao diagnóstico." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/95981.

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Made available in DSpace on 2014-06-11T19:27:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-04-10Bitstream added on 2014-06-13T18:32:19Z : No. of bitstreams: 1 borges_vp_me_jabo.pdf: 810273 bytes, checksum: 0704631ed3d05666adee30a0ec98e496 (MD5) Universidade Estadual Paulista (UNESP) A caquexia figura como uma das mais importantes causas de condenação total de frangos de corte durante a inspeção em abatedouros frigoríficos determinando grandes prejuízos ao setor avícola. Para melhor entender esta enfermidade foram estudados os aspectos macro e microscópicos de 400 aves caquéticas de um abatedouro frigorífico sob Inspeção Federal no Estado de Mato Grosso do Sul. Foram relatadas e catalogadas todas as lesões macro e microscópicas das aves caquéticas examinadas. Devido às diferentes alterações detectadas e aos diversos órgãos atingidos pôde-se concluir que as etiologias devem ser variadas. O fígado, sacos aéreos e pele foram os órgãos mais comumente comprometidos. O envolvimento do fígado, em vários graus e com lesões diferenciadas, em grande parcela dos casos induziu à percepção de que o comprometimento deste órgão - importante para a síntese protéica - está intimamente relacionado ao aparecimento de quadros de caquexia. A lesão de degeneração da cabeça femoral, embora não tenha sido uma alteração freqüentemente detectada têm correlação positiva com o aparecimento de casos de nefrite caseosa. O índice de aparecimento de lesões teciduais maior nos animais caquéticos que naqueles não caquéticos e o fato de que períodos curtos de privação alimentar não interferem no aparecimento de graus mais severos de caquexia são dados que corroboram para o entendimento de que esta é uma síndrome associada a enfermidades e não à fome. Cachexia is one of the most important causes of carcass downgrading in poultry inspection and it determines serious losses to poultry industry. To better understand this syndrome, the macro and microscopic aspects of 400 cachetic carcasses were studied in a slaughterhouse under Federal inspection in Mato Grosso do Sul State. Each macro and microscopic lesion was reported and classified. Because of the several alterations in many viscera it was possible to conclude that there must be a plenty of etiologies. Liver, air sacs and skin were the most compromised organs. Hepatic involvement in different levels induce to the perception that this important organ in protein synthesis is close related to cachexia cases. Femoral head degeneration although not frequently identified showed a positive correlation to caseous nephritis. Ali the studied lesions were greater in cachetic animais when compared to non-caquetic broilers. This data associated to the fact that short periods of time of food deprivation do not interfere in severe cases of cachexia corroborate to the understanding that this is a syndrome related to diseases and not to hunger.

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47

Hadziabdic, Sead [Verfasser]. "Transfer and structural alterations of resistance plasmids carrying carbapenemase-encoding genes in a broiler chicken infection model / Sead Hadziabdic." Berlin : Freie Universität Berlin, 2020. http://d-nb.info/1220691569/34.

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48

Gavin, Amanda Jane. "The impact of intensive genetic selection for improved performance in the broiler chicken on metabolic rate, morphology and body." Thesis, University of Glasgow, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.392647.

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McGill, Elizabeth Ruth Firman Jeffre D. "Effects of low crude protein diets with amino acid supplementation on broiler performance in the starter period." Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6457.

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Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 18, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Thesis advisor: Dr. Jeffre Firman. Includes bibliographical references.

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50

Colón, Guillermo J. "Avian musing feature space analysis." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44754.

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The purpose of this study was to analyze the possibility of utilizing known signal processing and machine learning algorithms to correlate environmental data to chicken vocalizations. The specific musing to be analyzed consist of not just one chicken's vocalizations but of a whole collective, it therefore becomes a chatter problem. There have been similar attempts to create such a correlation in the past but with singled out birds instead of a multitude. This study was performed on broiler chickens (birds used in meat production). One of the reasons why this correlation is useful is for the purpose of an automated control system. Utilizing the chickens own vocalization to determine the temperature, the humidity, the levels of ammonia among other environmental factors, reduces, and might even remove, the need for sophisticated sensors. Another factor that this study wanted to correlate was stress in the chickens to their vocalization. This has great implications in animal welfare, to guarantee that the animals are being properly take care off. Also, it has been shown that the meat of non-stressed chickens is of much better quality than the opposite. The audio was filtered and certain features were extracted to predict stress. The features considered were loudness, spectral centroid, spectral sparsity, temporal sparsity, transient index, temporal average, temporal standard deviation, temporal skewness, and temporal kurtosis. In the end, out of all the features analyzed it was shown that the kurtosis and loudness proved to be the best features for identifying stressed birds in audio.

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Dissertations / Theses on the topic 'Chicken broiler'

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