Dissertations / Theses on the topic 'Ruminant production'

Methane is a potent greenhouse gas with a global warming potential 21 times that of carbon dioxide. Globally, ruminants are the main anthropogenic contributors to methane release to the atmosphere. Methane is produced in the gastrointestinal tract of ruminants, mostly within the rumen by methanogenic archaea. However, methane production represents a loss of 2 to 12% of dietary gross energy for the animal, which could otherwise be available for growth or milk production. Therefore, mitigation of methane production by ruminants could produce both economic and environmental benefits, with more sustainable and energy efficient livestock, and offering a promising way of slowing global warming. Despite extensive research undertaken to find ways of reducing methane emissions from ruminants, progress has been relatively limited. Furthermore, there is still a lack of studies linking rumen microbiology and ruminant nutrition and production. The central purpose of this research was to investigate feed additives to reduce methane emissions and to understand associated changes that occur in the rumen microbiota. For the first experiment (Chapter 2), biochar was evaluated as an antimethanogenic compound for beef cattle. The in vitro gas production technique was used to study the effects of biochar on rumen fermentation and methane production. Overall, methane production was reduced by 5% by the addition of biochar compounds (10 g/kg of substrate). The observed reduction in methane produced was not associated with a change in volatile fatty acid profile suggesting biochar primarily inhibited fermentation. Ammonia concentration was significantly reduced with biochar inclusion. Because different biochars had different effects on methane production, further investigation of relationships between the physicochemical properties of biochars and antimethanogenic effects are necessary. However, due to the small reduction in methane production recorded, research with biochar was discontinued. Encapsulated nitrate was then explored as an antimethanogenic additive and as an alternative non-protein nitrogen source to urea (Chapter 3). The effect of using encapsulated nitrate as a replacement for urea or dietary protein, plus the addition of inorganic sulphur, on enteric methane emissions, nutrient digestibility, nitrogen utilization and microbial protein synthesis from crossbred beef steers were studied. In addition, nitrate toxicity and eating behaviour were investigated. The inclusion of encapsulated nitrate reduced methane production compared to urea and a true protein source, with no adverse effects on rumen fermentation or nitrogen metabolism and no effects with the inclusion of elemental sulphur. The level of addition of encapsulated nitrate (14.3 g nitrate /kg DM) and the time of adaptation chosen for this study (14 days) were adequate to avoid nitrate toxicity. Finally, the effects of adding nitrate inclusion to different basal diets on rumen microbial populations and relationships of these populations with methane production were investigated (Chapter 4). The V4 hypervariable regions of the bacterial and archaea 16S rRNA genes were amplified and sequenced. Effects on microbial population induced by nitrate were dependant on the basal diet but nitrate altered specific archaeal and bacterial OTUs consistently between studies. A direct and strong correlation between some archaea taxonomic groups and OTUs with methane production was observed.

Dans le domaine de l'alimentation des ruminants, les huiles essentielles, en raison de leur pouvoir antibactérien, sont considérées de plus en plus comme une des solutions alternatives aux antibiotiques tels que les ionophores. Cette étude a pour but de caractériser les effets de deux composés aromatiques issus des huiles essentielles (CHE), l'aldéhyde cinnamique (Ac) et le carvacrol (Cv). Quatre expérimentations sont menées, avec des méthodologies différentes : in vitro en culture batch, avec des doses de 10, 100 et 1000 ppm dans le milieu, un substrat reproduisant une ration simplifiée et des durées d'incubation de 4 et 16h ; in situ où deux types de ration, l'une riche en amidon (RA), l'autre riche en fibre (RF) sont utilisées avec deux temps d'adaptation aux CHE (3 et 21 jours), et où les effets des deux CHE administrés oralement à raison de 1 g/jour/vache en période de tarissement sont mesurés sur la disparition ruminale in sacco de l'amidon de maïs, des matières azotées de différentes sources protéiques, ainsi que des glucides pariétaux de la luzerne ; un bilan nutritionnel conduit sur vaches taries recevant les deux CHE séparément (à la dose quotidienne de 1 g/vache) et en association ; et enfin, de façon contemporaine au bilan, la mesure de l'effet de l’association des deux CHE sur la production laitière et la qualité du lait. Ln vitro, il existe un seuil compris entre 100 et 1000 ppm dans le milieu qui conduit à une inhibition pratiquement totale des activités fermentaires et traduit l'effet antimicrobien des CHE. Les réponses aux doses de 10 et 100 ppm ne sont globalement pas différentes. La dose de 10 ppm, correspondant approximativement à 1 g/j/vache, a donc été retenue dans les expérimentations in vivo. Certaines réponses aux CHE témoignent d'une amélioration potentielle de l'utilisation de l'énergie. Ils diminuent in vitro la production de méthane calculée à partir des AGV après 16h de fermentation. L'Ac augmente la proportion de propionate in vitro comme in sacco après 21 jours d'adaptation; cependant ces effets ne sont pas répétés lors de la réalisation des bilans nutritionnels ; ils seraient donc observés uniquement dans le cadre de rations particulièrement riches en glucides pariétaux ou concentrées en amidon. Le Cv augmente la digestion ruminale de l'ADF mesurée par la méthode des bilans ainsi que la disparition de l’ADF de luzerne in sacco avec la ration riche en amidon, ce qui conduit, d'après les caractéristiques des rations, à associer préférentiellement ce CHE aux rations contenant un minimum de 34 % d'amidon. L'effet des CHE sur les glucides de réserve semble par contre limité, puisque l'Ac diminue la disparition de l'amidon de maïs mesurée in sacco mais de façon numériquement plus marquée à court terme, et que cet effet n'apparaît pas avec ce CHE dans le bilan de l'utilisation digestive de l'amidon. D'autres résultats traduisent une amélioration probable de l'utilisation de l'azote. Les deux CHE diminuent la concentration du N-NH3 dans le milieu de culture après 16 heures d’incubation in vitro ainsi qu'in situ avec la ration riche en amidon. Le Cv augmente l’efficacité de la synthèse microbienne mesurée dans le cadre du bilan nutritionnel, avec une ration moyenne en terme d'apports en amidon et glucides pariétaux, et plus pauvre en MAT, comparativement aux rations RF et RA utilisées in sacco. L'association de l'Ac et du Cv administrée oralement à des vaches en lactation n'a cependant pas entraîné d'effet sur la production laitière; il semble toutefois que l'utilisation métabolique de l'azote soit légèrement améliorée, comme en témoigne la diminution significative de la teneur en urée du lait. A l'instar des antibiotiques ionophores, le Cv et l'Ac semblent donc pouvoir être utilisés pour modifier la digestion ruminale, afin d'orienter le métabolisme fermentaire vers une utilisation plus efficace de l'énergie et de l'azote chez le ruminant. Les conditions dans lesquelles ils expriment les réponses les plus favorables restent toutefois à préciser, ainsi que leur effet exact sur la microflore ruminale<br>Ln the area of ruminant feed, essential oils are increasingly being considered, on account of their antibacterial property, as one alternative solution to antibiotics such as ionophores. This study sets out to characterize the effects of two aromatic essential oil compounds (EOC), cinnamaldehyde (Ca) and carvacrol (Cv). Four experiments were conducted using different methodologies: in vitro batch culture with doses of 10, 100 and 1000 ppm in the medium, a substrate reproducing a simplified ration and incubation times of 4 and 16h; in situ in which two types of ration are used, one high starch (HS), the other high fibre (HF) with two adaptation times to EOCs (3 and 21 days), and in which the effects of the two EOCs administered orally at the rate of 1 g/day/cow during the dry period are measured on in sacco rumen disappearance of maize starch, nitrogen matter from different protein sources, and parietal carbohydrates of alfalfa; a nutrient intake analysis on dried off cows receiving both EOCs separately (daily dose of 1 g/cow) and in association; and finally, contemporary with nutrient intake analysis, measurement of the effect of the association of both EOCs on milk production and milk quality. Ln vitro, there exists a threshold of between 100 and 1000 ppm in the medium which leads to almost total inhibition of fermenting activities, translating the antimicrobial effects of the EOC. Responses to doses of 10 and 100 ppm do not differ globally. The dose of 10 ppm, approximately corresponding to 1 g/d/cow, was therefore chosen for the in vivo experiments. Some responses to the EOCs evidence a potential improvement in utilization of energy. They reduce in vitro production of methane calculated on VFA levels after 16 h fermentation. Ca increases the proportion of propionate both in vitro and in sacco after 21 days’adaptation; however these effects are not repeated in nutrient intake analysis; they are apparently therefore only seen when rations are particularly high in parietal carbohydrates or starch concentration. Cv increases rumen digestion of ADF measured using the nutrient analysis method, and the in sacco disappearance of alfalfa ADF with the high starch ration which, according to ration characteristics, leads to associating this EOC preferably with rations containing at least 34% starch. On the other hand, the effects of EOCs on reserve carbohydrates appear to be limited, since Ca reduces the disappearance of maize starch measured in sacco but with higher counts over the short term, while this effect is not seen with this EOC in the results on the digestive utilization of starch. Other results translate a probable improvement in the utilization of nitrogen. Both reduce the EOCs concentration of N-NH3 in the culture medium after 16 hours' in vitro and in situ incubation with the high starch ration. Cv increases the efficacy of microbial synthesis, as measured by the nutrient analysis method, with a ration providing average starch and parietal carbohydrate content but lower total nitrogen content, with respect to the HF and HS rations used in sacco. The association of Ca and Cv administered orally to lactating cows did not however evidence any effect on milk production; it would appear however that the metabolic utilization of nitrogen is slightly improved, as indicated by the significant reduction in the urea content of the milk. Similar to ionophore antibiotics, Cv and Ac therefore appear to have use in modifying ruminant digestion, to orient fermenting metabolism towards more efficient energy and nitrogen utilization in ruminants. However, the conditions under which they express the most favourable response remain to be specified, and also their exact effect on ruminant microflora

Les légumineuses permettent de réduire les intrants en élevage (engrais, concentrés) en raison notamment de leurs niveaux élevés en protéines. Cependant, à la fois pendant le processus d'ensilage et celui de fermentation dans le rumen, les protéines peuvent subir une importante dégradation, ce qui affecte la valeur nutritive des fourrages et induit des rejets d'azote (N) importants, notamment dans l'urine. Certaines légumineuses peuvent alors être d'un intérêt particulier car elles produisent des composés secondaires qui peuvent modifier positivement les processus fermentaires et digestifs. Ainsi, les tannins condensés (CT) présents dans le sainfoin (SF, Onobrychis viciifolia) sont capables de se lier aux protéines, réduisant leur dégradation dans le silo et le rumen et se traduisant par un transfert de l'excrétion d'azote de l'urine vers les fèces. Le trèfle violet (RC, Trifolium pratense) contient la polyphénoloxydase (PPO), une enzyme qui catalyse l'oxydation de différents composés phénoliques en quinones. Comme les CTs, les quinones sont capables de former des complexes avec les protéines permettant de réduire leur dégradation dans le silo et le rumen. L'objectif de cette thèse était alors d'étudier et de quantifier les bénéfices potentiels de l'utilisation de ces deux espèces de légumineuses bioactives sur i) la qualité et la conservation des ensilages, ii) la fermentation ruminale, l'efficacité digestive et les performances des ovins, et iii) l'empreinte environnementale (excrétion d'N et de CH4). Nous avons effectué deux essais in vitro et deux essais in vivo, basés sur des ensilages composés de ces deux légumineuses, seules ou en mélange avec une graminée (la fléole- T, Phleum pratense L.) qui nous a servie de contrôle. Les essais in vitro nous ont permis de nous focaliser sur la qualité et la conservation des ensilages ainsi que sur la fermentation ruminale, tandis que les essais in vivo se sont concentrés sur la performance et l'efficacité digestive des agneaux, ainsi que sur leur bilan azoté et leurs émissions de CH4. L'inclusion de légumineuses bioactives dans les ensilages d'herbe a amélioré la qualité du fourrage, la fermentation pendant le processus d'ensilage ainsi que la protection des protéines contre une dégradation au sein du silo et du rumen. Globalement, l'alimentation des agneaux avec des mélanges comportant ces légumineuses s'est traduite par une augmentation de l'ingestion de matière sèche, en comparaison des agneaux alimentés avec la graminée pure. Néanmoins, en raison de la digestibilité nettement plus faible de T-SF, probablement due à une composition et une nature des fibres différentes ainsi qu'à la présence de CT, les agneaux ayant reçu T-SF ont montré une ingestion et des performances plus faibles que ceux ayant reçu les ensilages contenant RC. Dans le rumen, il semble que les protéines de RC aient été plus protégées de la dégradation que celles de SF, tandis que dans la suite du tractus digestif, les complexes formés entre protéines et CT (avec SF) se seraient moins dissociés que ceux formés entre protéines et quinones (avec RC), ce qui pourrait en partie expliquer le transfert d'excrétion de l'N de l'urine vers les fèces, observé chez les agneaux alimentés avec T-SF et bénéfique pour l'environnement. SF a également permis de réduire légèrement les émissions de CH4. Ainsi, utiliser des légumineuses bioactives dans les pratiques d'alimentation des ruminants apparaît une stratégie prometteuse pour fournir des produits animaux de façon plus durable. Nos résultats montrent que chaque espèce apporte des avantages différents, plutôt orientés vers la qualité de l'aliment et les performances animales pour RC mais plutôt orientés vers la réduction des rejets pour SF. Des recherches complémentaires sont donc nécessaires pour mieux caractériser ces avantages et élargir les investigations à d'autres espèces, d'autres mélanges et d'autres bénéfices potentiels. (...)<br>Fodder legume species allow to reduce inputs in livestock breeding systems (fertilizer, concentrates) notably because they contain high levels of crude proteins which are of primary importance in ruminant nutrition. However, during both silage and rumen fermentation processes, proteins are submitted to degradation which affects forage nutritive value and leads to nitrogen (N) losses notably via urine. Some specific legumes can then be of particular interest as they produce plant secondary compounds that can positively affect silage and digestive processes. Condensed tannins (CTs) present in sainfoin (SF, Onobrychis viciifolia) are able to bind with proteins thereby reducing their degradation in the silo and the rumen, resulting in a shift in N excretion from urine to faeces. Red clover (RC, Trifolium pratense) contains polyphenol oxidase (PPO), an enzyme that catalyses the oxidation of different phenolics into quinones. As CTs, quinones are able to form complexes with proteins that will similarly reduce their degradation in the silo and the rumen. The aim of this thesis was to investigate and quantify the potential benefits of using these two bioactive legume species on i) quality and conservation of silages, ii) rumen fermentation, digestive efficiency and sheep performance, and iii) environmental footprint (N excretion and CH4 emissions). We conducted two in vitro and two in vivo trials which were based on silages of pure legumes or of different mixtures with the grass species (timothy T, Phleum pratense L.), which served as control. In the in vitro trials, we focussed on silage quality, silage conservation and rumen fermentation, while in the in vivo trials, we focussed on lambs' performance, digestion efficiency, N balance and CH4 emissions. Including bioactive legumes in mixtures with grass improved, compared to pure grass, forage quality and fermentation during the silage making process, as well as proteins' protection from degradation within both the silos and the rumen. Lambs fed with the mixtures involving legumes responded with an increase in DM intake compared to their counterparts fed with T. Nevertheless, due to a possibly different fibre composition and to the presence of CT which impaired SF digestibility, lambs that consumed T-SF showed lower intake and performance than those that received RC-containing silages. In the rumen, RC proteins appeared more protected from degradation than SF ones, while in the subsequent parts of the digestive tract, the proteins-CT complexes (from SF) might less dissociate than the proteins-quinones ones (from RC). This could partly explain the environment-friendly shift in N excretion from urine to faeces when animals are fed with T-SF. SF also allowed to slightly reduce CH4 emissions. Thus, utilizing bioactive legumes in livestock feeding practices is a promising strategy to produce animal products more sustainably. Our results show different benefits relative to the bioactive legume species involved, directed towards boosted forage quality and animals' performance for RC but towards lowered wastes for SF. Further research is thus needed to better characterize these benefits and enlarging investigations to other plant species, mixtures and potential benefits (e.g. health). This will help to determine the appropriate choice of plant species according to the objectives

Thesis (PhD (Forest and Wood Science))—University of Stellenbosch, 2007.<br>Sustainable livestock production in semi-arid Botswana could be improved through tree planting on-farm to provide much needed protein and shade. Such action can be encouraged if the growth, productivity, nutritional value of trees and their contribution to mass gain of livestock are known.. A study at Malotwana investigated two indigenous species, Acacia galpinii and Faidherbia albida, and two exotic species, Leucaena diversifolia and L. leucocephala, at three spacings in a randomised complete block design replicated five times. The three spacings represented 400, 317 and 241 trees per hectare. The study was conducted over 6.5 years. Indigenous trees were sampled biennially and exotics annually to evaluate crown width, height, stem diameter, stem number and stem volume index. Complete plant harvesting of exotic trees at 2.5, 4.5 and 6.5 years evaluated agroforestry production. Leaves from all four species and pods of exotic species were analysed for chemical composition. Two groups of eight lambs were balanced for mass at selection for an on-farm feeding trial. Browse from exotic trees, comprising a 2:1 ratio of pods to leaves, was fed at 30% as supplement to hay to one group whose mean mass was contrasted with that of the control group fed sorghum bran at 30%. A. galpinii was a promising species, adaptable to planting away from its origin. Its crown width ranged from 5.86 m in high density plots to 6.08 m at low density and was significantly different among stands (p = 0.0406) at 6.5 years. Diameter at breast height (dbh) was significantly different among stands aged 6.5 years (p = 0.0003) and ranged between 10.38 cm at high density to 12.48 cm in low density plots, demonstrating a capacity to provide both shade and poles on-farm. At 4.5 years, F. albida attained a mean height of 4.5 m and 4.5 cm in dbh but suffered 67% mortality during a severe drought. Annual fodder production of 0.647 and 0.996 metric tonnes ha-1 for leaves and pods of L. diversifolia and 1.237 and 1.431 for L. leucocephala was recorded in years of average rainfall. Yields of 0.3 and 0.59 metric tonnes ha-1 were recorded for both species in the driest year. Equally good agroforestry production was obtained from both low and high density stands suggesting that low density plantings, which foster higher plant survival and reduce disease incidence, are best suited to the semi-arid conditions of Botswana. The crude protein of leaves ranged between 16.26 (L. diversifolia) and 25.25% (F. albida). They were highly digestible with more than twice the calcium content livestock require. Crude protein and digestibility measures were significantly different among leaves and varied significantly at different spacings (p<0.0001). Pods of the exotic species contained significantly more protein than the leaves (p<0.0001). Lambs supplemented with browse gained 102.33 g per animal per day while the control group gained 83.95 g. There were significant differences between groups during growth (p<0.05). Growing of A. galpinii, complemented with L. diversifolia and L. leucocephala, can supply short and long term feed, and greatly enhance livestock production while diversifying farm feed sources

[EN] The main objective of this Thesis was to study the energy metabolism in small ruminants under different nutrition sceneries. As methodology we utilized indirect calorimetry instead of direct calorimetry or feeding trials. Within indirect calorimetry we worked with a portable open circuit gas exchange system with a head hood. This open circuit respiration system permitted completed the whole energy balance and evaluate the efficiency of utilization of the energy of the diet for different physiological circumstances as milk production in dairy goats or maintenance in sheep. Besides, we could quantify in each trial some of the wastes related to environmental pollution as CH4 emissions and excretion of nitrogen in feces and urine. In this thesis three experiments were designed, two in dairy goats and other in sheep as we described below. In the first experiment, digestibility, energy balance, carbon and nitrogen balance, milk performance, rumen parameters and milk fatty acids and metabolites were obtained. Metabolic cages and open circuit indirect calorimetry system were the methods applied. Treatments consist in two mixed diets with alfalfa as forage. Within the concentrate, oat grain was replaced with rice bran. No significant differences were found for metabolizable energy intake (MEI), 1254kJ/kg of BW0.75 on average, and heat production (HP); 640 kJ/kg of BW0.75 on average. No differences were obtained for milk production (2.2 kg/d on average) and milk fat was greater in the rice bran diet (6.9% vs. 5.3% for rice bran and oat diets, respectively). Energy balance was positive and milk metabolites correlated these found. Regards to CH4 emissions, determined in vivo by gas exchange indirect calorimetry, goats fed the rice bran significantly reduced methane production (23.2 g/d vs 30.1 g/d). In the second experiment, we also used two types of diets, but in this case we substituted the forage and maintained the same concentrate; in one of the diets a grass (Maralfafa [Pennisetum sp.]- M diet) was used as forage and in the other an extensively used leguminous (Alfalfa [Medicago sativa]- A diet). Methods and analysis were the same that in Experiment 1, and here we include metabolites in urine and blood plasma. The dry matter intake was higher for diet A (1.8 vs 1.6 kg/d, respectively) and digestibility coefficients were higher for diet M. However, no significant differences were shown in MEI (1089 kJ/kg of BW0.75, on average) and HP (639 kJ/kg of BW0.75on average). Higher milk yield was observed in A diet than M diet (1.8 vs. 1.7 kg/d, respectively) and metabolites in urine, plasma and milk indicated better use of diet A than M, while no differences in milk composition were found (5% of fat and 4.3% of protein). Methane production was higher for A diet (28.5 g/d) than M diet (25.9 g/d), although these differences were not statistically significant. In the third experiment, energy partition was compared in two sheep breeds (Manchega vs. Guirra) fed above maintenance. We fed again with mixed diets and metabolic cages, indirect calorimetry, nitrogen balance and integral calculus were the tools used for these energy partitioning approach. An approximation of division of heat production was done. ME for maintenence was estimated at 354 kJ/kg of BW0.75and day, on average for the two breeds. Basal metabolic rate was different between breeds; 270 vs. 247 kJ/kg of BW0.75for Guirra and Manchega, respectively.<br>[ES] El objetivo principal de esta tesis fue estudiar el metabolismo energético en pequeños rumiantes bajo diferentes escenarios de nutrición. Como metodología se utilizó la calorimetría indirecta en vez de calorimetría directa o pruebas de alimentación. Dentro de la calorimetría indirecta trabajamos con un sistema portátil de circuito abierto de intercambio de gases con una "urna" (Heat hood). Este sistema de circuito abierto de respiración nos permitió completar todo el balance energético y evaluar la eficiencia de la utilización de la energía de la dieta para diferentes estados fisiológicos como producción de leche en cabras u oveja en mantenimiento. Además fue posible cuantificar en cada ensayo algunas perdidas relacionadas con la contaminación ambiental como emisiones de CH4 y la excreción de nitrógeno en heces y orina. En esta tesis se diseñaron tres experimentos, dos en cabras en lactación y otro en ovejas como describimos a continuación. En el primer experimento se han determinado, digestibilidad, balance energético, balance carbono nitrógeno, producción de leche, parámetros ruminales, ácidos grasos y metabolitos en leche. Jaulas metabólicas y un sistema de circuito abierto de calorimetría indirecta fue el método aplicado. Los tratamientos consistieron en dos dietas mixtas con alfalfa como forraje y dentro del concentrado el grano de avena fue reemplazado por cilindro de arroz. No se encontraron diferencias significativas en la energía metabolizable ingerida (MEI) de 1254 kJ/kg PV0.75 en promedio y una producción de calor (HP) de 640 kJ/kg PV0.75 en promedio. La producción de leche no presentó diferencias significativas entre las dos dietas, (2,2 kg/den promedio), la grasa de la leche fue mayor en la dieta de cilindro de arroz (6,9% vs. 5,3% para cilindro de arroz y avena respectivamente). El balance energético fue positivo y correlacionado a los metabolitos en leche determinados. En cuanto a las emisiones de CH4, determinadas en vivo mediante el intercambio de gases por calorimetría indirecta, las cabras alimentadas con el subproducto redujeron significativamente la producción de metano (23,2 g / d vs 30,1 g / d.). En el segundo experimento, también utilizamos dos tipos de dietas, pero en este caso sustituimos los forrajes y mantuvimos el mismo pienso; en una de las dietas se utilizó como forraje una gramínea (Maralfafa [Pennisetum sp.] - dieta M) y en el otro una leguminosa de uso extendido (Alfalfa [Medicago sativa] - dieta A). Los métodos de análisis y análisis fueron los mismos que los utilizados en el Experimento 1, y se incluyeron además análisis de metabolitos en orina y plasma. La materia seca ingerida fue mayor para dieta A (1,8 vs 1,6 kg/d, respectivamente), los coeficientes de digestibilidad fueron mayores para la dieta M. Sin embargo, no se encontraron diferencias significativas en MEI (1089 kJ/kg PV0.75, en promedio) y HP 639 kJ/kg PV0.75, en promedio). La producción de leche fue mayor en la dieta A que la dieta M, (1,8 vs. 1,7 kg/d, respectively) y los metabolitos en orina, plasma y leche indican un mejor aprovechamiento de la dieta A. No se presentaron diferencias en la composición de la leche (5% de grasa and 4.3% de proteína). La producción de metano fue mayor para la dieta A (28,5 g/d) que para la dieta M (25,9 g/d), aunque estas diferencias no fueron estadísticamente significativas. En el tercer experimento se compararon la partición energética en dos razas de ovejas (Manchega vs. Guirra) en mantenimiento. Fueron alimentadas con dietas mixtas en jaulas metabólicas, calorimetría indirecta, balance carbono nitrógeno y cálculos integrales fueron las herramientas utilizadas para un aproximación de la partición energética. Se realizó una aproximación de división de producción de calor. El ME para mantenimiento se estimó en 354 kJ/kg PV0.75/ día, en promedio para las dos razas. Las diferencias en la tasa metabólica basal entre las razas fu<br>[CAT] El principal objectiu d'aquesta tesi va ser estudiar el metabolism energètic en xicotets ruminants baix diferents escenaris de nutrició. Com a metodologia es va utilitzar la calorimetria indirecta en compte de calorimetria directa o proves d'alimentació. Dins de la calorimetria indirecta treballarem amb un sistema portatil de circuit obert d'intercanvi de gasos amb "urna" (Heat hood). Aquest sistema de respiració de circuit obert ens va permetre completar tot el balanç energètic i avaluar l'eficiència de la utilització de l'energia de la dieta per a diferents circumstàncies fisiològiques com produccion de llet en cabres o manteniment en ovelles. A més va ser possible quantificar en cada assaig algunes perdues relacionades amb la contaminacion ambiental com a emissions de CH4 i l'excreció de nitrogen en femta i orina. En aquesta tesi es van dissenyar tres experiments, dos en cabres en lactación i un altre en ovelles com vam descriure a continuació. En el primer experiment s'han determinat,digestibilidad, balanç energètic, balanç carboni nitrogen, producció de llet, paràmetres ruminales, àcids grassos i metabòlits en llet. Gàbies metabòliques i un sistema de circuit obert de calorimetria indirecta va ser el mètode aplicat. Els tractaments van consistir en dues dietes mixtes amb alfals com a farratge i dins del concentrat el gra de civada va ser reemplaçat per cilindre d'arròs. No es van trobar diferències significatives en l'energia metabolizable ingerida (MEI) de 1254 kJ/kg PV0.75 en mitjana i una producció de calor (HP) de 640 kJ/kg PV0.75 en mitjana. La producció de llet no va presentar diferències significatives entre les dues dietes, (2.2 kg/donen mitjana), el greix de la llet va ser major en la dieta de cilindre d'arròs (6.9% vs. 5.3% per a cilindre d'arròs i civada respectivament). El balanç energètic va ser positiu i correlacionat als metabòlits en llet determinats. Quant a les emissions de CH4, determinades en viu mitjançant l'intercanvi de gasos per calorimetria indirecta, les cabres alimentades amb el subproducte van reduir significativament la producció de metà (23.2 g / d vs 30.1 g / d.).En el segon experiment, també utilitzem dos tipus de dietes, però en aquest cas substituïm els farratges i vam mantenir el mateix pinso; en una de les dietes es va utilitzar com a farratge una gramínea (Maralfafa [Pennisetum sp.] - dieta M) i en l'altre una **leguminosa d'ús estès (Alfals [Medicago sativa] - dieta A). Els mètodes d'anàlisis i anàlisis van ser els mateixos que els utilitzats en l'Experiment 1, i es van incloure a més anàlisi de metabòlits en orina i plasma. La matèria seca ingerida va ser major per a dieta A (1,8 vs 1,6 kg/d, respectivament), els coeficients de digestibilidad van ser majors per a la dieta M. No obstant açò no es van trobar diferències significatives en MEI (1089 kJ/kg PV0.75, en mitjana) i HP 639 kJ/kg PV0.75, en mitjana). La producció de llet va ser major en la dieta Al fet que la dieta M, (1,8 vs. 1,7 kg/d, respectively) i els metabòlits en orina, plasma i llet indiquen un millor aprofitament de la dieta A. No es van presentar diferències en la composició de la llet (5% de greix i 4.3% de proteïna). La producció de metà va ser major per a la dieta A (28,5 g/d) que per a la dieta M (25,9 g/d), encara que aquestes diferències no van anar estadísticament significatives. En el tercer experiment es van comparar la partició energètica en dues races d'ovelles (Manxega vs. Guirra) en manteniment. Van ser alimentades amb dietes mixtes en gàbies metabòliques, calorimetria indirecta, balanç carboni nitrogen i càlculs integrals van ser les eines utilitzades per a un aproximació de la partició energètica. Es va realitzar una aproximació de divisió de producció de calor. L'EM para manteniment es va estimar en 354 kJ/kg PV0.75 / dia, en mitjana per a les dues races. Les diferències en la taxa metabòlica basal entre les races va ser de 2<br>Criscioni Ferreira, PF. (2016). Application of an open circuit indirect calorimetry system for gaseous exchange measurements in small ruminant nutrition [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/64069<br>TESIS

Os animais contribuem para o aumento da concentração de metano na atmosfera através da fermentação de tanques de esterco e da fermentação do trato digestivo (fermentação entérica). A fermentação entérica dos ruminantes, pseudo-ruminantes (cavalos, asno, mulas) e não ruminantes produzem em média 80 Tg/ano de metano e representam 28 % do metano antropogênico global emitido, dos quais 95 % provêm dos ruminantes. Os objetivos destes trabalhos foram (i) rastrear novos materiais com potencial forrageiro que contenham tanino e que promovam redução de metano entérico; (ii) estudar a influência dessas plantas sobre a produção de metano e parâmetros fermentativos in vitro; e (iii) estudar a influência dessas plantas sobre a população de Fibrobacter succinogenes e a comunidade metanogênica no meio de fermentação. Os resultados são apresentados na forma de capítulos, sendo o primeiro objetivo descrito no Capítulo 3, no qual é descrita a caracterização das leguminosas taniníferas Styzolobium aterrimum (STA), Styzolobium deeringianum (STD), Leucaena leucocephala(LEU), Mimosa caesalpiniaefolia Benth (MIC). Estas plantas foram avaliadas pela composição química e quantificação de compostos fenólicos e bioensaio até 96 h de incubação in vitro; tendo Cynodon x cynodon (CYN) como controle para avaliar a produção de gás potencial (A), a fase lag (L), a taxa fraccional de fermentação (\'mü\') e o incremento de gás devido à adição de PEG após 8, 24 e 48 h de incubação nas cinco plantas. As leguminosas tiveram melhor desempenho fermentativo que a gramínea, com exceção de MIC. Entretanto, a fermentação de todas leguminosas foi limitada diferentemente pela presença de tanino, da fibra indigestível ou pela ação aditiva de ambos. Entre todas as plantas, LEU mostrou ser uma forragem de boa qualidade para suplementação protéica em dietas de ovinos, assim como STA e STD, contanto que para estas haja um melhor manejo de produção para evitar o alto conteúdo de fibras, especialmente de FDA. MIC poderia ser incluído na dieta de ovinos em baixa concentração, não com a finalidade principal de suplementação protéica, mas explorando esta leguminosa como aditivo para mitigação de metano. No Capítulo 4 são apresentados os resultados de outro ensaio in vitro (segundo objetivo). A técnica in vitro de produção de gás foi utilizada para avaliar as quatro leguminosas taniníferas (STA, STD, LEU e MIC) e o CYN como controle em dois horários, no t1/2 (tempo para obtenção da metade da GP) e após 24 h de incubação, medindo a produção total de gás, metano, amônia, ácidos graxos de cadeia curta (AGCC), massa microbiana (MM) e a degradabilidade verdadeira da matéria seca (VDMS). A produção de metano em t1/2 foi reduzida (P < 0,05) com adição das leguminosas em 17% e quando relacionado à VDMS, esta redução alcançou em média 50% com LEU e STA e 37% com MIC e STD. LEU e STA causaram aumento significante na MM seguida por STD, MIC e CYN. A relação MM/SCFA em t1/2 foram maiores para LEU (14,7) e STA (14,1) seguida por STD (6,1), MIC (5,6) e CYN (4,6). A maior MM para LEU e STA sugere uma produção de ATP maior, porém, as diferentes proporções de AGCC demonstraram diferentes rotas de aquisição de ATP. O Capítulo 5 se refere à quantificação de linhagens de bactéria ruminal, a qual foi realizada utilizando primers específicos para detecção de seqüências de gene 16S rDNA para metanogênicas e para a bactéria celulolítica Fibrobacter succinogenes através da reação em cadeia da polimerase em tempo real (qPCR). Foi também investigado a influência das leguminosas na comunidade metanogênica através da eletroforese em gel com gradiente denaturante (DGGE) de seqüências de gene 16S rDNA. As metanogênicas em t1/2 foram 2,0 e 0,9 vezes menores que com STA e LEU comparadas com o controle, mas foram 2,5 e 0,5 vezes maiores com MIC e STD. A população de F.succinogenes foi 2,3 e 1,8 vezes menores do que o controle quando LEU e STA foram incubadas. A análise de DGGE para metanogênicas resultou em diferente distribuição de bandas com os tratamentos. CYN apresentou algumas bandas mais fortes, as quais se tornaram fracas com as leguminosas, exceto em STA. Algumas bandas tanto desapareceram, como em LEU, STA e MIC, ou se tornaram mais fracas, especialmente em STA. MIC apresentou ligeiro aumento no número de bandas fracas. É confirmado que as plantas taniníferas estudadas foram capazes de reduzir a emissão de metano com diferentes proporções dos produtos finais de fermentação, afetando negativamente a população de F. succinogenes e causando alterações na estrutura da comunidade metanogênicas<br>Animals contribute to increasing the methane concentration in the atmosphere through the fermentation of livestock manure and the fermentation in the digestive tract, e.g, enteric fermentation. The enteric fermentation of ruminants, pseudoruminants (horses, donkeys, mules) and non-ruminants produce an average of 80 Tg/year of methane and comprise 28 % of global anthropogenic methane emission, from which 95% arise from ruminants. The aims of this study were (i) to scan new potential forage containing tannin, which may reduce enteric methane emission; (ii) to study the influence of those plants on methane production and fermentative parameters in vitro; (iii) to study the influence of those plants on the population of Fibrobacter succinogenes and the methanogen community in the fermentation fluid. The results are presented in the form of chapters, being the first objective studied described in the Chapter 3, in which refers to the characterization of the tannin-rich legumes Styzolobium aterrimum (STA), Styzolobium deeringianum (STD), Leucaena leucocephala(LEU), Mimosa caesalpiniaefolia Benth (MIC). They were appraised for the chemical composition, quantification of phenolic compounds and bioassay up to 96 h in vitro incubation using Cynondon x cynodon (CYN) as control, to evaluate the potential gas production, (A), lag phase (L), fractional rate of gas production (\'mü\') and the gas increment due to PEG addition after 8, 24 and 48 h incubation of the five plants. Legumes showed better fermentative performance (except MIC) than the grass. However, each legumes fermentation was limited diferently by the presence of condensed tannin or the indigestible fiber or by the additive action of both. Among the plants, LEU showed good quality forage for protein supplementation in sheep diets as well as STA and STD as long there is an agriculture management to reduce indigestible fiber, specially ADF. MIC could be included in a sheep diet in low concentration, aiming not the protein supplementation, but exploiting it as an additive to methane mitigation. In Chapter 4 the second object is discussed describing an in vitro gas test to evaluate the four tannin-rich legumes (STA, STD, LEU and MIC), and CYN as control at two main time points: t1/2 (time of half maximal gas production) and 24 h, measuring total gas production , methane, ammonia, short chain fatty acids (SCFA), microbial mass growth (MM) and true substrate degradability (TSD). Methane production at t1/2 was reduced (P < 0.05) with addition of legumes by 17 % but when related to TSD this reduction reached on average 50 % with LEU and STA and 37% with MIC and STD. LEU and STA caused a significant increase in MM followed by STD, MIC, and CYN. Additionally, high MM/SCFA ratios in t1/2 were found in LEU (14.7) and STA (14.1) and followed by STD (6.1), MIC (5.6) and CYN (4.6). The higher MM in LEU and STA suggested higher ATP production; however, the different proportion of the SCFA demonstrated different routes of ATP acquisition. Chapter 5 refers to the quantification of specific strains of rumen bacteria, which was performed using designed primers for detecting 16S rDNA gene sequences for methanogens and the cellulolytic bacteria Fibrobacter succinogenes by real-time polymerase chain reaction (qPCR). Also, the influence of those four legumes on the methanogenic community was investigated using denaturing gradient gel electrophoresis (DGGE) of 16S rDNA gene. Methanogens at t1/2 were 2.0 fold and 0.9 fold lower with STA and LEU compared to the control, but they were 2.5 fold and 0.5 fold higher with MIC and STD. F. succinogenes population was 2.3 and 1.8 fold lower than the control when LEU and STA was applied. DGGE analysis of the methanogenic population resulted in different band patterns with treatments. CYN presented some strong bands, which became weaker with the legumes, except in STA. Some bands either disappeared, as in LEU, STA and MIC, or became weaker, especially in STA. MIC increased slightly the number of weak bands. It is confirmed that the studied taninniferous plants were able to reduce enteric methane with different fermentation products proportions, as well negatively affected F. succinogenes population and caused changes in the methanogenic community structure

Submitted by (edna.saturno@ufrpe.br) on 2016-12-13T16:39:39Z No. of bitstreams: 1 Kelly Cristina dos Santos.pdf: 2838245 bytes, checksum: 83360fa623d10eab2ee6df3369b537ff (MD5)<br>Made available in DSpace on 2016-12-13T16:39:39Z (GMT). No. of bitstreams: 1 Kelly Cristina dos Santos.pdf: 2838245 bytes, checksum: 83360fa623d10eab2ee6df3369b537ff (MD5) Previous issue date: 2013-07-25<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES<br>Considering the importance of food diversity available for feeding ruminants in the semiarid aimed to estimate the nutritional value of the following forage species: maniçoba (Manihot psedoglazziovii Pax. & Hoffm); sabiá (Mimosa caesapiniifolia Benth); mororó (Bauhinia Bauhinia cheilantha (Bong.) Steud.); Leucaena (Leucaena leucocephala Lam.); cunhã (Clitorea ternatea) and Gliricidia (Gliricidia sepium), from the chemical composition, carbohydrates and proteins fractionations, degradation parameters and ruminal fermentation, in vitro digestibility of dry matter and also ruminal and post-rumen protein degradation. The samples were collected in four replicates per species in the Experimental Caatinga Field of Embrapa Semi-Arid (CPATSA Petrolina City, state of Pernambuco. The concentrations of carbohydrates and protein fractionations were determined based on the Cornell Net Carbohydrate and Protein System (CNCPS). The evaluation of the degradation of organic matter and products of ruminal fermentation was performed using in vitro semiautomatic gas production technique. Ruminal degradability and intestinal digestibility of protein were estimated using the three steps technique. Although all the evaluated species presented crude protein above 110 g/kg DM, and the leucaena followed by manioc, stood out showing the highest levels (P <.05). The highest concentrations (P <0.05) of total phenols (FT), total tannins (TT) and condensed tannins (CT) were found in sabiá and mororó species, and considering the other species evaluated there are not variation. Cunhã species followed by Leucaena had the highest concentration of the B2 fraction (potentially digestible fiber) and the other species did not differ (P> 0.05) among themselves. The C fraction (unavailable fiber fraction) was found in greater amounts (P <0.05) in sabiá and mororó. The nitrogen fractions of high and medium ruminal degradation were found in higher concentrations in cunhã and leucaena, in relation to sabiá which had the lowest concentration. Fraction C, which corresponds to the unavailable nitrogen to animal metabolism was higher in sabiá and mororó species (P <0.05) and lower for cunhã, leucaena and maniçoba species. Maniçoba, gliricídia and to a lesser extent, leucaena provided higher (P <0.05) truly degradation of organic matter (TDMO g/kg OM), otherwise sabiá and mororó showed less values. Gliricídia, leucaena and maniçoba stood out, showing high digestibility potential (P <0.05).The cunhã had the highest percentage of rumen degradable protein (RDP) and the lowest percentage (P <0.05) of ruminal non degradable protein (RUP %CP). The leucaena presented higher intestinal protein digestibility (ID g/kg DM) as well as higher values of digestible RUP (RUPd g/kg DM). Gliricídia, Leucaena and maniçoba presented potential for reducing enteric CH4 production, without any effect on the nutrients degradation, digestibility and supply of readily fermentable carbohydrates high potential. The leucaena stands out as a source of rumen protected protein degradation and released in the intestine.<br>Ao se considerar a importância da diversidade de alimentos disponíveis para a alimentação de ruminantes no semiárido, objetivou-se estimar o valor nutricional das espécies forrageiras: maniçoba (Manihot psedoglazziovii Pax. & Hoffm); sabiá (Mimosa caesapiniifolia Benth); mororó (Bauhinia cheilantha (Bong.) Steud.); leucena (Leucaena leucocephala Lam.); cunhã (Clitorea ternatea) e gliricídia (Gliricidia sepium), a partir da composição química, do fracionamento dos carboidratos e proteínas, dos parâmetros de degradação e fermentação ruminal, da digestibilidade in vitro da matéria seca e da degradação ruminal e pós-rúmen da proteína. As amostras foram coletadas, em quatro repetições por espécie, no campo experimental da Caatinga, pertencente a Embrapa Semiárido (CPATSA), no município de Petrolina-PE. O fracionamento dos carboidratos e proteínas foi realizado com base no Cornell Net Carbohydrate and Protein System (CNCPS). A avaliação da degradação da matéria orgânica e dos produtos da fermentação ruminal foi realizada por meio da técnica in vitro semiautomática de produção de gases. A degradabilidade ruminal e digestibilidade intestinal da proteína foram estimadas por meio da técnica dos três estágios. Apesar de todas as espécies avaliadas apresentarem teores de proteína bruta acima de 110 g/kg de MS, a leucena, seguida da maniçoba, destacaram-se apresentando os maiores teores (P<0,05). As maiores concentrações (P<0,05) de fenóis totais (FT), taninos totais (TT) e taninos condensados (TC) foram encontrados nas espécies sabiá e mororó, em relação às demais espécies avaliadas. A cunhã, seguida da leucena, apresentou a maior concentração da fração B2 (fibra potencialmente digestível) e as demais espécies não diferiram (P>0,05) entre si. A fração C (fração indisponível da fibra) foi encontrada em maior quantidade (P<0,05) no sabiá e no mororó. As frações nitrogenadas de alta e média degradação ruminal, foram encontradas em maiores concentrações na cunhã e na leucena, em relação ao sabiá que apresentou a menor concentração. A fração C, que corresponde ao nitrogênio que está indisponível para o metabolismo animal, foi maior nas espécies sabiá e mororó (P<0,05) e menor para as espécies cunhã, leucena e maniçoba. A maniçoba, a gliricídia e, em menor escala, a leucena, proporcionaram maior (P<0,05) degradação verdadeira da matéria orgânica (DVMO g/kg MO), em contraste sabiá e mororó apresentaram menor degradação. Gliricícia, leucena e maniçoba destacaram-se, apresentando elevado potencial (P<0,05) de digestibilidade. A cunhã apresentou o maior percentual de proteína degradável no rúmen (PDR) e menor percentual (P<0,05) de proteína não degradável no rúmen (PNDR %PB). A leucena apresentou maior digestibilidade intestinal (DI g/kg MS) da proteína, bem como maiores valores de PNDR digestível (PNDRd g/kg MS). Gliricídia, leucena e maniçoba apresentaram potencial de redução da produção de CH4 entérico, sem efeitos negativos sobre a degradação dos nutrientes. Essas espécies apresentaram também alto potencial de digestibilidade e fornecimento de carboidratos prontamente fermentescíveis. A leucena destacou-se como fonte de proteína protegida da degradação ruminal e disponibilizada no intestino.

In Brazil, with the continued expansion of agriculture for supplying demands from international markets, progressive increases in emissions of green house gases are expected. The purpose of the project was hypothesized with three major approaches, 1) Strategies to mitigate methane emission in small ruminant production systems; 2) Identify tropical plants and individual bioactive compound against methanogenic propertie and 3) In vivo evaluation of the nutrients metabolism of Santa Ines sheep fed with tropical plants. For this, we have performed three experiments. The first study (Expt. 1) was designed to determine the in vitro effects of three tropical tannin rich plants such as Leucaena leucocephala (LL), Mimosa caesalpineafolia (MC), Schinus molle (SM) and one non-tannin rich plant Medicavo sativa (MS) for their anti-methanogenic properties when used with and without polyethylene glycol (PEG). All plants had significantly (P<0.05) influenced the degraded organic matter (TDOM) and degraded neutral detergent fiber (DNDF), especially LL, which had most influence on these parameters compared to other tannin containing plants. LL had positive response on antimethanogenic effects; its nutrient degradability was higher than that of other tannin containing plants. The second study (Expt. 2) was set to evaluate the effect of different organic extracts from the whole plant methanolic extract (MHE) of LL on in vitro gas production and to characterize the chemical constituents by using gas chromatography coupled with mass spectroscopy (GC-MS). Major abundant compounds present at the relative percentages of MHE were found to be stigmasterol trimethyl ester (TMS), neophytadiene, palmitic acid TMS, ?-Linolenic acid TMS and 2, 3, 5, 6-Tetra-M-Anisylbenzene. The effects of additions of different extracts in terms of nutrient degradability (TDOM and DNDF) were increased by all extracts. This study explained that the hexane extract from whole plant MHE was effective against methanogenic activity. The objective of the third study (Expt. 3) was to study the effect of LL plant leaves on rumen fermentation, apparent nutrient digestibility, nitrogen balance and methane production in Santa Ines sheep. The animals were divided in three groups in which they were fed with (i) 88% Tifton 85-hay (Cynodon dactylon) and 12% soyabean meal (Control group, n=4); (ii) 28% Tifton 85-hay (Cynodon dactylon) and 72% LL plus 20 ml solution containing 10g/day/animal of PEG (With PEG group - WPEG, n=6); (iii) 28% Tifton 85-hay (Cynodon dactylon) and 72% LL plus 20 ml of distilled water (Without PEG group- WOPEG, n=6). Nutrient intake (dry matter, organic matter, acid detergent fiber, lignin and crude protein) were higher in WPEG and WOPEG compared to the control group, except neutral detergent fiber intake. Apparent digestibilities and nitrogen metabolism had non-significant effects between the treatments. However, CH4 emissions were significantly lower in WPEG and WOPEG than the control. Furthermore, expressions of microbial populations of methanogens in WPEG had lower tendency than that of WOPEG and control. The most salient findings of this study were that, using plant rich in tannin in diets of small ruminants, we can get more benefits in terms of replacing the source of protein in the diet (food safety) and reduced production of enteric CH4 (animal production)<br>No Brasil, com expansão da agricultura para suprir as exigências dos mercados internacionais, são esperados aumentos progressivos nas emissões de gases do efeito estufa. O objetivo do projeto foi hipotetisado com três abordagens principais, 1) estratégias para mitigar emissões de metano em sistemas de produção de pequenos ruminantes; 2) identificar plantas tropicais com compostos bioativos com propriedades anti metanogénicas e 3) avaliação in vivo do metabolismo de nutrientes em ovelhas Santa Inês alimentadas com planta taninífera. Para isso, foram efetuados três experimentos. O primeiro estudo (Expt 1) foi concebido para estudar os efeitos in vitro de plantas tropicais ricas em tanino como Leucaena leucocephala (LL), Mimosa caesalpineafolia (MC) e Schinus molle (SM) e uma planta não taninífera, Medicavo sativa (MS) quanto às propriedades anti-metanogénicas quando usadas com e sem polietileno glicol (PEG). Todas as plantas significativamente (P < 0.05) influenciaram na matéria orgânica degradada (MOD) e na fibra em detergente neutro degradada (FDND), especialmente a LL, que teve maior influência sobre estes parâmetros, em comparação com as outras plantas que contém tanino LL teve resposta positiva sobre os efeitos de antimethanogênicos e a degradabilidade dos nutrientes foi maior do que a das outras plantas que contém tanino. O segundo estudo (Expt 2) foi definido para avaliar o efeito de diferentes extratos orgânicos a partir do extrato metanólico da planta (EMP) de LL na produção de gás in vitro e caracterizar os constituintes químicos usando cromatografia gasosa acoplada com espectroscopia de massa (GC-MS). Os compostos mais abundantemente encontrados, em termos de percentagens relativas do EMP, foram o éster de trimetil estigmasterol, neofitadina, ácido palmítico, ácido ?-linolênico e 2, 3, 5, 6-Tetra-M-anizil -benzeno. Os efeitos de adições dos diferentes extratos orgânicos, em termos de degradabilidade de nutriente (MOD e NDFD) foram aumentados para todos os extratos. Este estudo explicou que o extrato de hexano a partir do EMP foi eficaz na atividade anti metanogênicas em modificar a degradação ruminal de nutrientes. O objetivo do terceiro estudo (Expt 3) foi estudar o efeito das folhas da planta LL na fermentação ruminal, digestibilidade aparente de nutrientes, balanço de nitrogênio e produção de metano em ovinos Santa Inês. Os animais foram divididos em três grupos em que eles foram alimentados com (i) 88% feno de Tifton-85 (Cynodon dactylon) e 12% de farelo de soja (Grupo controle, n = 4); (ii) 28% feno de Tifton-85 (Cynodon dactylon) e 72% LL mais 20 ml solução contendo 10g/dia/animal de PEG (grupo com PEG - CPEG, n = 6); (iii) 28% feno de Tifton-85 (Cynodon dactylon) e 72% LL mais 20 ml de água destilada (sem PEG-grupo-SPEG, n = 6). A ingestão de nutrientes (matéria seca, matéria orgânica, fibra em detergente ácido, lignina e proteína bruta) foram maiores no grupos CPEG e SPEG em relação ao grupo controle, exceto a ingestão de fibra em detergente neutro. As digestibilidades aparentes e o metabolismo do nitrogênio não apresentaram efeitos significativos entre os tratamentos. No entanto, as emissões de CH4 foram significativamente inferiores nos grupos CPEG e SPEG em comparação com o grupo controle. Além disso, as expressões de populações microbianas de metanogênicas no grupo CPEG apresentaram tendência menor do que nos grupos SPEG e controle. As conclusões mais salientes do presente estudo foram que, usando planta rica em tanino em dietas de pequenos ruminantes, poderemos ter mais benefícios em termos de substituição da fonte de proteína da dieta (segurança alimentar) e redução da produção de CH4 entérico

A preocupação com a segurança alimentar e o aquecimento global pressiona a cadeia de produção de ruminantes a buscar alternativas para incremento na produtividade e redução nas emissões dos gases de efeito estufa, uma vez que essa atividade é responsável por grande parte das emissões de metano (CH4) entérico. O desenvolvimento de produtos enzimáticos para uso na nutrição de ruminantes torna-se de grande valia para contribuir com a demanda alimentar e reduzir os impactos ambientais. O objetivo do presente estudo foi avaliar o uso de um extrato de enzimas fibrolíticas (EEF), composto por endoglucanases, exoglucanases e xilanases, produzido pelo fungo Trichoderma reesei utilizando como substrato resíduos da indústria canavieira, sobre a digestibilidade, fermentação ruminal e desempenho de ovinos em crescimento, conduzidos através de dois experimentos. No experimento 1, foi avaliado a adição de doses crescentes (0, 10, 100, 1000 e 10000 µL g-1 de substrato) do EEF sobre a produção total de gases e CH4, degradabilidade e fermentação ruminal de três forrageiras tropicais (Cynodon spp., Panicum maximum e Cenchrus ciliares L.) em um ensaio in vitro, com o objetivo de verificar a possibilidade de uso do EEF na dieta de ruminantes sem prejudicar os parâmetros fermentativos. Verificou-se que os resultados foram dependentes da dose e do substrato utilizados. Contudo, foi verificado aumento na produção total de gases e CH4 e na degradabilidade de todas as forrageiras utilizadas com a dose mais alta do EEF. Conclui-se que o EEF pode ser utilizado na dieta de ruminantes como alternativa para incremento na degradabilidade de forrageiras tropicais. O experimento 2 foi dividido em duas fases conduzidas com o objetivo de avaliar o efeito do EEF sobre a digestibilidade aparente dos nutrientes, fermentação ruminal, desempenho animal e produção de CH4 entérico de 19 ovinos em crescimento divididos em dois grupos experimentais, controle (CTL) e enzima (ENZ), recebendo dieta composta de 70% de feno de Tifton-85 e 30% de mistura concentrada. O EEF foi aplicado diretamente no feno 24 horas antes do fornecimento da refeição. Na Fase I, avaliou-se o efeito de doses crescentes (0, 20, 40 e 80 µL) do EEF sobre a hidrólise da fibra e posteriormente a dose com melhor resposta foi utilizada nos estudos de digestibilidade aparente dos nutrientes e fermentação ruminal. A dose de 40 µL foi selecionada para ser utilizada no ensaio in vivo, pois apresentou melhores respostas sobre a redução nas frações fibrosas. Os animais suplementados com o EEF apresentaram maior digestibilidade da fibra em detergente ácido e maior produção de valerato. Na Fase II, foi avaliado o efeito do EEF sobre o desempenho, saúde e produção de CH4 entérico de ovinos em crescimento. Os procedimentos utilizados foram os mesmos descritos na Fase I. A suplementação do EEF proporcionou maior percentual médio de ganho de peso e menor produção de CH4 entérico por kg de matéria seca ingerida. As análises sanguíneas demonstraram que o EEF não prejudicou a saúde dos animais. Conclui-se que o EEF pode ser utilizado na dieta animal sem trazer riscos à saúde, além de ser uma estratégia para aumento na produtividade animal e contribuir com a mitigação de CH4 entérico de ovinos em crescimento<br>Concern about food security and global warming is pressing the ruminant production chain to seek alternatives to increase productivity and reduce greenhouse gas emissions, as this activity accounts for most of the enteric methane (CH4) emissions. The development of enzyme products for use in ruminant nutrition is of great value in order to contribute to food demand and reduce environmental impacts. The aim of the present study was to evaluate the use of a fibrolytic enzyme extract (FEE), produced by the fungus Trichoderma reesei using as substrate residues from the sugar cane industry, on the digestibility, ruminal fermentation and performance of growing sheep, conducted through two experiments. In the experiment 1, the addition of increasing doses (0, 10, 100, 1000 and 10000 ?L g-1) of the FEE on the total gas and CH4 production, degradability and ruminal fermentation of three tropical forages (Cynodon spp., Panicum maximum and Cenchrus ciliares L.) in an in vitro assay, with the objective of verifying the possibility of use of the FEE in the diet of ruminants without harming the fermentative parameters and, consequently, animal health. The results were found to be dose and substrate dependent. However, there was an increase in total gas and CH4 production and in the degradability of all forages used with the highest dose of FEE. It is concluded that the EPS can be used in the diet of ruminants as an alternative to increase the degradability of tropical forages. The experiment 2 was divided in two phases, with the objective of evaluating the effect of the FEE on the apparent digestibility of nutrients, ruminal fermentation, animal performance and enteric CH4 production of 19 growing sheep divided in two experimental groups, control (CTL) and enzyme (ENZ), receiving a diet composed of 70% of Tifton-85 hay and 30% of concentrated mixture. The FEE was applied directly to the hay 24 hours before the meal. In Phase I, the effect of increasing doses (0, 20, 40 and 80 ?L) of the FEE on fiber hydrolysis was evaluated and the dose with the best response was then used in the studies of apparent digestibility of nutrients and ruminal fermentation. The 40 ?L dose was selected to be used in the in vivo assay because it presented better responses on the reduction in fibrous fractions. The animals supplemented with FEE showed higher acid digestible fiber digestibility and higher valerate production. The other parameters were not influenced by the addition of FEE. In Phase II, the effect of FEE was evaluated on the performance, health and production of Enteric CH4 of growing sheep. The procedures used were the same as described in Phase I. The supplementation of the FEE provided a higher percentage of weight gain and lower enteric CH4 production per kg of ingested dry matter. Blood tests showed that FEE did not affect animal health. It is concluded that FEE can be used in the animal diet without presenting health risks, besides being a strategy to increase animal productivity and contribute to the mitigation of enteric CH4 of growing sheep

L'un des facteurs de variation majeur de la production quantitative et qualitative de lait chez les ruminants est l'éjection du lait. Celle-ci est provoquée par déclenchement de la contraction des cellules myoépithéliales par l'ocytocine (OT), au moment et/ou entre la traite et est responsable de la vidange des alvéoles vers la citerne. L'effet galactopoi͏̈étique de l'OT pourrait donc être expliqué par son effet de transfert du lait alvéolaire, mais également par d'autres effets sur l'épithélium mammaire sans que cela soit prouvé aujourd'hui. Les objectifs de notre travail étaient : (1) l'étude de l'effet galactopoi͏̈étique de l'augmentation de la fréquence de traite et plus particulièrement du rôle de l'OT dans cet effet chez la vache et la chèvre. L'augmentation de la fréquence de traite augmente significativement la production de 8 et 9 % chez la vache et la chèvre, confirmant l'effet galactopoi͏̈étique global d'une traite chez ces 2 espèces. Les injections de doses physiologiques d'OT provoquent des réponses différentes chez nos 2 modèles. Chez la vache, elles n'augmenent la production que lorsqu'elles sont accompagnées d'une vidange de la mamelle. En revanche, chez la chèvre, elles augmentent seules, la production en fonction des capacités de stockage citernal des animaux. L'effet galactopoi͏̈étique de l'OT, au moment et entre les traites, est donc démontré chez nos 2 modèles. Il peut être principalement expliqué par son action d'éjection/transfert du lait alvéolaire, qui optimiserait la production en limitant les effets négatifs de la stase lactée. L'augmentation du transfert alvéolaire ne modifiant pas la composition du lait chez la vache et la chèvre l'Ot entraîne

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico<br>The research aims to characterize this the creation of small ruminants in northeastern Brazil. To this end, initially we aimed to analyze the importance of cluster analysis for characterization of small ruminant production systems, using as a methodological tool to literature. Thus, it was observed that the cluster analysis methodology to characterize the animal production systems, is a technique used worldwide to identify the successful cases, advantageous aspects and obstacles in order to support programs that facilitate the leverage of farming. Subsequently, based on data collected from field research through interviews with 224 farmers in four northeastern states, it used the cluster analysis technique called cluster analysis, aimed specifically identify the homogeneous groups and check leveraging factors and restrictors groups in relation to the general characteristics of the producer and his property, the composition of herds, the socioeconomic aspects of producer and practices related to reproductive management, food and health. Thus, five homogeneous groups have been identified (or clusters) of small ruminant producers in northeastern Brazil. Group I represents 25% of the producers examined, where farms have little area, however, high stocking density, highlighting the presence of cattle more quantitative in that group, characterized as "small farms focused on milk production ". Group II contains 20% of analyzed producers, with the quantitative smaller herds among the groups, lower adoption of management practices and a higher frequency of exclusive breeders of goats and sheep, being defined as "small flocks not technified". Group III is the largest group, comprising 28% of respondents creators, where the goat herd significantly exceeds the sheep flock, being named as "traditional goat farmers". Group IV absorbs 16% of the most experienced producers, with the largest areas of observed properties, showing also a larger quantity of animals and a higher percentage of adoption of management practices, which are defined as "large farms technicality". Group V covers 11% of the youngest producers, the lowest group analyzed where mixed farms of sheep, goats and cattle are most frequent, representing 33% of producers in that group, named "emerging mixed farms." There was generally an increase in all groups regarding the feeding management used by Northeastern producers caused by the promotion of the development of the rural sector policies. They identified some obstacles to be overcome, especially with regard to reproductive health and herd management.<br>A pesquisa realizada neste pretendeu caracterizar a criaÃÃo de pequenos ruminantes na RegiÃo Nordeste do Brasil. Para tanto, inicialmente, teve como objetivo analisar a importÃncia da anÃlise de clusters para caracterizaÃÃo de sistemas de produÃÃo de pequenos ruminantes, utilizando-se como ferramenta metodolÃgica a pesquisa bibliogrÃfica. Dessa forma, observou- se que a metodologia de anÃlise de clusters, visando à caracterizaÃÃo dos sistemas de produÃÃo animal, à uma tÃcnica utilizada no mundo todo, visando identificar os casos exitosos, aspectos vantajosos e impedimentos, de forma a subsidiar aÃÃes que propiciem a alavancagem da atividade agropecuÃria. Posteriormente, a partir de dados coletados de uma pesquisa de campo, por meio de entrevistas com 224 produtores de quatro estados nordestinos, utilizou-se a tÃcnica de anÃlise de agrupamento denominada de anÃlise de clusters, visando, especificamente, identificar os grupos homogÃneos existentes e verificar os fatores alavancadores e restritores dos grupos em relaÃÃo Ãs caracterÃsticas gerais do produtor e de sua propriedade, à composiÃÃo dos rebanhos, aos aspectos socioeconÃmicos dos produtores e Ãs prÃticas relativas ao manejo reprodutivo, alimentar e sanitÃrio. Dessa forma, foram identificados cinco grupos homogÃneos (ou clusters) de produtores de pequenos ruminantes na RegiÃo Nordeste do Brasil. O grupo I representa 25% dos produtores analisados, onde as fazendas tÃm pouca Ãrea, no entanto, elevada densidade animal, destacando-se a presenÃa do rebanho bovino com maior quantitativo nesse agrupamento, caracterizando-se como âpequenas fazendas centradas na produÃÃo de leiteâ. O grupo II contÃm 20% dos produtores analisados, apresentando os menores quantitativos de rebanhos dentre os grupos, menor adoÃÃo de prÃticas de manejo e a maior frequÃncia de criatÃrios exclusivos de caprinos e ovinos, sendo definido como âpequenos rebanhos nÃo tecnificadosâ. O grupo III à o maior grupo, contendo 28% dos criadores entrevistados, onde o rebanho caprino supera sensivelmente o rebanho ovino, sendo nomeado como âcaprinocultores tradicionaisâ. O grupo IV absorve 16% dos produtores mais experientes, com as maiores Ãreas de propriedades observadas, apresentando, tambÃm, um maior quantitativo de animais e um maior percentual de adoÃÃo de prÃticas de manejo, sendo definidos como âgrandes fazendas tecnificadasâ. O grupo V abrange 11% dos produtores mais jovens, sendo o menor grupo analisado, onde os criatÃrios mistos de ovinos, caprinos e bovinos sÃo de maior frequÃncia, representando 33% dos produtores desse grupo, nomeado de âcriatÃrios mistos emergentesâ. Verificou-se, em geral, uma evoluÃÃo em todos os grupos no tocante ao manejo alimentar utilizado pelos produtores nordestinos, provocada por polÃticas de promoÃÃo do desenvolvimento do setor rural. Identificaram-se alguns entraves a serem superados, em especial no tocante ao manejo reprodutivo e sanitÃrio dos rebanhos.

L'acidose ruminale est l'une des préoccupations majeures des exploitations laitières actuelles. Les levures vivantes (LV) ont été largement étudiées et utilisées chez les vaches laitières pour stabiliser la fermentation ruminale. Récemment, la mesure du potentiel redox ruminal (Eh, en mV) a été considérée comme un outil intéressant pour indiquer le trouble de la fermentation ruminale. L'effet positif de LV sur Eh ruminal a été rapporté, mais il reste variable selon les conditions expérimentales. Les objectifs de ce travail étaient de fournir une meilleure compréhension du mode d'action de LV et de définir la condition optimale de l'utilisation de LV chez les vaches laitières. La première partie de ce travail a consisté en une analyse quantitative des résultats de 22 expériences avec des vaches laitières canulées. La deuxième partie de ce travail a consisté à vérifier certains des résultats de l'analyse quantitative par une expérience chez des vaches en lactation. En utilisant l'analyse quantitative de données existantes provenant d'expériences antérieures, nous avons clarifié la relation entre le Eh ruminal et d'autres paramètres ruminaux principaux tels que le pH et le profil VFA, et suggéré que les variations de Eh pourraient être liées au transfert d'électrons dans les réactions dans le rumen. En outre, la réponse du Eh après la supplémentation en LV était également liée à celle du profil AGV ruminal, suggérant que l'effet de LV sur le profil VFA était atteint par l'augmentation du pouvoir réducteur, reflétant un meilleur transfert d'électrons dans le rumen. L'analyse a en outre démontré que la régulation du Eh ruminal par LV serait particulièrement efficace lorsque le risque de troubles digestifs est élevé. Puisque l'influence des caractéristiques de la ration sur le Eh ruminal a été quantifiée, l'effet de LV dans un régime donné pourrait être estimé indirectement. En outre, l'analyse quantitative a également révélé que la réponse de Eh suite à la supplémentation en LV était associée à la quantité de sucres solubles ingérée. L'expérience in vivo chez des vaches en début de lactation a confirmé un effet plus important de LV sur Eh ruminal avec une ration riche en sucres solubles, et a démontré que la supplémentation en LV avait un impact sur la richesse des bactéries, et que les métabolites ont également été influencés par la supplémentation en LV, probablement associée à la diminution du Eh ruminal<br>Ruminal acidosis is one of the major concerns of current dairy farms. Live yeasts (LY) have been extensively studied and used in dairy cows for stabilization of rumen fermentation. Recently, measurement of ruminal redox potential (Eh, in mV) has been considered as an interesting tool to indicate ruminal fermentation disorder. The positive effect of LY on ruminal Eh has been reported, but it remains variable according to the experimental conditions. The aims of this work was to provide better understanding of mode of actions of LY, and to define the optimal condition of LY utilization in dairy cows. The first part of this work consisted to quantitative analysis of existing results from 22 experiments with cannulated dairy cattle. The second part of this work consisted to verify some of the results from quantitative analysis by an in vivo experiment in lactating cows. By using quantitative analysis of existing data from previously conducted experiments, we clarified the relationship between ruminal redox and other main ruminal parameters such as pH and VFA profile, and suggested that Eh variations might be related to the transfer of electrons in the reactions producing VFAs in the rumen. Moreover, response of ruminal Eh following live yeast supplementation was also related to that of ruminal VFA profile, which suggested that the effect of LY on VFA profile was achieved via the increase of reducing power, possibly reflected improved electron transfer and use in the rumen. The analysis further demonstrated that the regulation of ruminal Eh by LY would be particularly effective when risk of digestive disorder is high. Since the influence of dietary characteristics on ruminal Eh was quantified, the effect of LY in a given diet could be indirectly estimated. In addition, quantitative analysis also associated the response of ruminal Eh following LY supplementation to the intake of soluble sugars. The in vivo experiment in early-lactating cows confirmed greater effect of LY on ruminal Eh in diet rich in soluble sugars, and further demonstrated that i) LY supplementation tended to impact the richness of ruminal bacteria, and ii) some unidentified metabolites were also influenced by LY supplementation, probably associated to the decrease of ruminal Eh

O presente relatório tem como objetivo descrever as atividades realizadas no âmbito do estágio curricular do Mestrado Integrado em Medicina Veterinária da Universidade de Évora. Numa primeira parte, será descrita a casuística acompanhada ao longo do estágio, incluindo os procedimentos de profilaxia, sanidade, clínica médica, clínica cirúrgica e assistência reprodutiva. Dentro destas várias componentes, serão descritos com mais detalhe os casos que foram mais frequentes e/ou mais interessantes. Posteriormente, será apresentada uma revisão bibliográfica a propósito da febre Q, com particular abordagem sobre a espécie caprina. Nesta revisão, incluem-se tópicos como: etiologia, sinais clínicos, diagnóstico e tratamento da doença. Por fim, será abordado um estudo de caso sobre a eficácia de uma vacina implementada no âmbito da profilaxia da febre Q, na exploração Barão e Barão Lda. Os resultados demonstraram que, efetivamente, se verificou uma redução na taxa de abortos, após a implementação do protocolo vacinal; Abstract: Clinical medical and surgery in livestock species This report aims to describe the activities carried out within the scope of the curricular internship of the Master degree in Veterinary Medicine of Universidade de Évora. In the first part, will be described the followed activities along the internship, including the procedures of prophylaxis, internal medicine, surgery and reproductive management. Within these several components, will be described in more detail the cases that were more frequent and/or more interesting. Posteriorly, will be presented a bibliographic review about Q fever with particular approach on caprine species. In this review, are included topics like: etiology, clinical signs, diagnostics and treatment of the disease. Lastly, will be described a case study about the efficiency of a vaccine implemented in scope of Q fever profilaxy in Barão e Barão Lda.. The results have demonstrated that, effectively, it was verified a reduction in the abortion rate after the implementation of the vaccine protocol.

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico<br>O presente trabalho tem por objetivo principal efetuar a caracterizaÃÃo e avaliaÃÃo do desempenho econÃmico dos sistemas de produÃÃo de ovinos da raÃa Morada Nova no Estado do CearÃ. Para tanto foram aplicados questionÃrios junto aos produtores de ovinos da raÃa Morada Nova no Estado do CearÃ. Para caracterizaÃÃo tÃcnica, dividiu-se o sistema de produÃÃo de ovinos em quatro componentes: gerenciamento do produtor, infra-estrutura do sistema de produÃÃo, manejo dos rebanhos e desempenho dos rebanhos. Em seguida, foram determinados os Ãndices tecnolÃgicos para cada componente, separadamente e para o conjunto deles, com base na respectiva tecnologia recomendada. Para a caracterizaÃÃo socioeconÃmica dos produtores, foram analisados sete fatores, a saber: infra-estrutura e produÃÃo de volumosos, rebanhos e manejo de produÃÃo, produÃÃo, aspectos ambientais, mÃo-de-obra, crÃdito rural e administraÃÃo do empreendimento. A anÃlise econÃmica foi feita utilizando-se a metodologia do Sistema Integrado de Custos AgropecuÃrios â CUSTAGRI. Foram identificados quatro nÃveis tecnolÃgicos de sistemas de produÃÃo que foram usados para a anÃlise dos aspectos socioeconÃmicos, estimativas de custos e avaliaÃÃo de rentabilidade. Os sistemas de produÃÃo de ovinos Morados Nova mais tecnificados mostraram-se lucrativos e capazes de viabilizar o desenvolvimento sustentÃvel no meio rural, proporcionando a fixaÃÃo do homem no campo com emprego e renda. As principais dificuldades observadas pelos produtores estÃo ligadas à mÃo-de-obra desqualificada, polÃticas de crÃdito insuficientes e falta de polÃticas pÃblicas focadas na atividade.<br>This chapter has the aim to make the technical analysis of production systems in Morada Nova sheep to complement the project "Characterization and basis for the genetic improvement of sheep Morada Nova", coordinated by Embrapa Goats and Sheep, with the financial support of Banco do Nordeste (FUNDECI / ETENE). In order to achieve this objective, primary research was conducted with data collected through the application of questionnaires to the sheep farmers of the municip ality of Morada Nova, Cearà State. To assess the technological level, the system of sheep was divided into four components: the producer management, infrastructure, production system, herd management and performance of the herds. Next, we determined the te chnological indices for each component separately and for all of them, based on its recommended technology. We found four production systems baptized by the technology index for each producer, being called "high technology gap" - level D, "regular technolog ical gap" - level C, "low technology gap" - level B and "high art " - level A. It was found that 17% of farmers fall in the level A, 33% at level B, Level C in 33% and 17% at level D.

Volatile fatty acids (VFA) are important products of ruminal fermentation. The VFA are not only the major source of energy to the ruminant animals but also influence methane production in the rumen. Therefore it is important to understand mechanism controlling VFA production and to depict VFA production in a model. This will allow us to devise strategies to enhance energy utilization and reduce methane production in ruminant livestock. An evaluation of a mechanistic model in predicting VFA production was conducted and equations were introduced into the model to improve the predictions. Later a continuous culture experiment was conducted to test the hypothesis on which those equations were based on. A mechanistic model -" Molly, was evaluated using a dataset with reported VFA production rates. The results of residual error analysis indicated that the root mean square prediction errors (RMSPE) were 63, 63, and 49% for acetate, propionate and butyrate, respectively. An assessment from two studies reporting VFA production revealed a potential of reducing errors of prediction by representing interconversion among VFA. In the second study, equations based on thermodynamics influence of pH and VFA concentration were introduced in the model to represent interconversion among VFA. The parameters for de novo VFA production and VFA absorption were re derived with (VFAInt) and without (BASE) the new interconversion equations. There were some improvements in the VFA concentration predictions but the improvements were both in VFAInt and BASE models. The RMSPE of VFA production were still above 50% for acetate, propionate and butyrate. The larger errors of predictions were attributed to measurement variation in VFA production literature, or possible incorrect rate constants for interconversion equations. Finally, a third study was conducted to assess the effect of pH, and VFA concentration on VFA and methane production in continuous culture. The treatments consisted of control, 20 mmol/d acetate infusion (INFAC), 7 mmol/d propionate infusion (INFPR), and low pH (LOWPH). Individual isotopes of acetate, propionate and butyrate were infused in the fermenters to estimate interconversions among VFA. With LOWPH treatment methane emission was reduced whereas production of propionate was increased. Hydrogen production was higher in INFAC indicating that some of the acetate could have been degraded to CO2 and H2. It was estimated that around 3 % of de novo acetate was converted to propionate and 9 % to butyrate. Exchange between propionate and butyrate was insignificant and below 1% of de novo production of either VFA. However, treatments did not affect interconversion rates among VFA. These results indicated that pH and VFA concentration do not have thermodynamic influence on VFA interconversion as hypothesized.<br>Ph. D.

As exigências das condições higiênico-sanitárias na produção de animais de interesse zootécnico vêm aumentando progressivamente dada à necessidade de aliar-se produtividade a produtos de alta qualidade para atender a mercados consumidores cada vez mais exigentes. Nesse sentido, a utilização de antimicrobianos, tanto na profilaxia como na terapêutica, permanece como estratégia de controle para vários microrganismos patogênicos, de importância não apenas para a produção animal como também para a saúde humana, ainda que restrições ao uso indiscriminado desses produtos têm se intensificado. Não obstante, o uso excessivo desses produtos está associado à seleção de microrganismos resistentes nas áreas de produção. Por outro lado, investigações sobre circulação de cepas resistentes em rebanhos animais, até então restritas a populações humanas, ainda permanecem limitadas no Brasil. Bactérias do gênero Enterococcus, integrantes usuais da microbiota gastrointestinal animal e humana, são indicadoras ambientais de contaminação fecal e tem-se tornado objeto de preocupação em saúde pública e veterinária dada a ocorrência de cepas resistentes à vancomicina (VRE). O presente trabalho teve como objetivo isolar, quantificar e caracterizar VRE presentes em amostras fecais de ovinos oriundos de pequenas propriedades das regiões centro-leste e nordeste do estado de São Paulo. Para tanto, 132 amostras fecais foram coletadas diretamente do reto dos animais ou do piso das instalações. As amostras foram semeadas em ágar m-Enterococcus e subcultivadas em Ágar Bile Esculina acrescido de 6 &micro;g/mL de vancomicina (ABEV), para confirmação de Enterococcus spp e detecção de cepas resistentes. Procedeu-se igualmente a observação da morfologia, características tintoriais, bioquímicas e moleculares. O número máximo de Enterococcus spp. encontrado foi de 2,6 × 105 e 1,70 × 105 UFC/g de fezes do ambiente e dos animais, respectivamente. Na caracterização bioquímica espécies mais prevalentes foram: Enterococcus faecalis e Vagococcus fluvialis. No ABEV, houve crescimento de colônias VRE em 33 das 84 amostras de ovinos-caprinos e em 21 das 48 amostras ambientais, representando, respectivamente 46,7% e 29,3% das amostras analisadas. A análise por multiplex PCR das 54 cepas VRE obtidas indicaram que 23 (43%), 22 (41%), 2 (3,5%) e 2 (3,5%) foram positivas, respectivamente, para os genes vanC2/C3, vanC1, vanA e vanB, sendo que para 5,3% dos isolados nenhum produto foi amplificado, sugerindo a possível ocorrência de genes dos demais grupos van conhecidos entre os isolados. Os resultados obtidos indicam, de forma inédita no país, a circulação de VRE em propriedades produtoras de ovinos e caprinos, sem ocorrência de manifestações clínicas aparentes nos animais, porém com possíveis riscos à saúde dos produtores e profissionais envolvidos, bem como a eventuais consumidores.<br>Demands for sanitary conditions in animal farming have been increasing progressively given the need to combine productivity and high quality products to support increasingly demanding consumer markets. In this context, antimicrobial drugs used in prevention as well as in therapy remain as the control strategy for several pathogenic microorganisms, not important only in animal production but also in human health, although restrictions for the indiscriminate use of these drugs have been intensified. However, the excessive use of these products has been associated to the selection of resistant microorganisms in production areas. On the other hand, investigation on strains of public health importance circulating in animal herds is still limited in Brazil. Enterococcus genus bacteria, usually present in animal and human gastrointestinal microbiota, are environmental indicators of fecal contamination and have become a concerning subject in public and veterinary health given the occurrence of strains resistant to vancomycin (VRE). The present study aimed to isolate, quantify and characterize VRE present in stool samples of sheep and goats from several farms in the center-east and northeast regions of São Paulo State. Swabs collected one hundred and thirty-two stool samples either directly from the animal\'s rectum or from the ground. Samples were plated onto m-Enterococcus agar plates and subcultivated in Bile esculin agar with 6 &micro;g/mL of vancomycin (BEAV) to confirm Enterococcus spp and detect resistant samples. Colonies were identified by colonial morphology, Gram\'s staining, biochemical, and molecular profile. The highest colony count was equal to 2.6 × 105 and 1.7 × 105 CFU/g of feces from environmental and animal samples, respectively. Regarding biochemical characterization, Enterococcus faecalis e Vagococcus fluvialis were the most prevalent species. VRE was detected on BEAV in 33 out of 84 sheep-goat samples and in 21 out of 48 ambient samples, indicating a positivity rate of 46.7% and 29.3% respectively in the investigated samples. Analysis by multiplex PCR of the obtained 54 VRE strains indicated that 23 (43%), 22 (41%) 2 (3.5%) and 2 (3.5%) were positive, respectively, for the vanC2/C3, vanC1, vanA and vanB genes, and no product was amplified for 5.3% of the isolates, suggesting the possible occurrence of other known van gene groups among the isolates. The results obtained in this study indicate, for the first time in the studied areas, the circulation of VRE in sheep and goat farms, with no occurrence of apparent clinical signs in the animals, but with possible health risks to the farmers and workers involved, as well as potential consumers.

Cette thèse avait pour objectif d'évaluer la défaunation comme technique permettant une meilleure nutrition des ruminants. La défaunation entraîne une augmentation du flux d'azote (non ammoniacal) au niveau du duodénum. Cependant, des études de la littérature indiquent que l'effet de la défaunation sur les productions animales (viande, lait et laine) est variable. Notre hypothèse de travail est que le rapport azote / énergie (PDIN / UF) de la ration est le principal facteur de variation des effets observés. . . La défaunation améliore l'indice de consommation des animaux défaunés ( -1. 4 g MS / g de croît). L'ensemble de ces résultats est confirmé par l'étude de nos rations expérimentales. En conclusion, le rapport azote / énergie de la ration module les effets de la défaunation, quand l'énergie n'est pas limitante. En zone tropicale humide, la défaunation ne présenterait un intérêt que pour les rations mixtes et les vieux fourrages. L'intérêt de la défaunation en ZTH reste à confirmer, notamment pour les jeunes fourrages et la canne à sucre (pauvre en azote, riche en sucre)<br>The aim of this thesis was to evaluate defaunation as a technique, that allows a better nutrition of ruminants. Defaunation lead to an increase of non ammonia-nitrogen flow at the duodenum (NAN duo. ). . . The bilbliographic synthesis indicated an enhancement of the shape of volatil fatty acids (VFAs) in the rumen (increase of propionate) after defaunation, whereas microbial cellulolysis decreased ( - 4. 7% DrNDF). The increased intestinal nitrogen flow and the enhanced shape of VFAs contribute to the enhanced metabolic use of energetic nutrients. Thus, defaunation led to an increase of food conversion efficiency (- 1. 4 g DM / g growth). These results are confirmed by our experimental diets studies. As a conclusion, the nitrogen /energy ratio of the diet modulate defaunation effect, while energy is not the growth limiting factor. The interest of defaunation in humid tropical area need to be confirmed, especially for young forage and sugar cane (low on nitrogen, high on glycoside)

Globally agriculture and livestock producers have come under increasing pressure over the environmental impact of production systems. The objectives of this study were to re-calculate the direct methane (CH4) and nitrous oxide (N2O) emissions of livestock production systems in South Africa, taking into consideration the uniqueness of the South African scenario and to identify and evaluate possible greenhouse gas mitigation strategies for extensive production systems. It is important to generate accurate greenhouse gas (GHG) baseline figures to develop South Africa’s capacity to understand and reduce GHG emissions emitted from the livestock sector. Livestock produce GHG’s in the form of methane from enteric fermentation and nitrous oxide and methane from manure management and manure deposited on pastures and rangeland by grazing animals. Agriculture, forestry and land use (corrected for carbon sink values) emitted an estimated 4.9% of South African GHG gases in 2004, which makes it the third largest GHG contributor in South Africa after the energy industry and industrial processes. Livestock produced approximately 27% of the national methane emissions and 98% of the agricultural sector’s methane emissions in 2004. Methane is a potent GHG that remains in the atmosphere for approximately 9 to 15 years and is 28 times more effective in trapping heat in the atmosphere than carbon dioxide (CO2) over a 100-year period. Nitrous oxide has an atmospheric lifetime of 150 years and a global warming potential of 265 times that of CO2 over a 100-year period. South African livestock production is based on a unique combination of commercial (intensive and extensive) and emerging and communal (subsistence) production systems. The levels of productivity and efficiency in these production systems vary greatly in certain areas and it is important to distinguish between them when calculating GHG emissions. Previous inventories were conducted on a national scale utilizing IPCC default values (Tier 1 approach) for some or all of the emission calculations. These emission factors do not distinguish effectively between classes of animals, production efficiencies, and production systems. They are often based on assumptions of animals utilizing diets which are not representative of South African production systems. The IPCC Tier 2 methodology seeks to define animals, animal productivity, diet quality and management circumstances to support a more accurate estimate of feed intake for use in estimating methane production from enteric fermentation. It was also considered important to do separate calculations for each province as provinces differ in vegetation or biomes and production systems which may require different approaches to mitigation recommendations. Due to the heterogeneity of available feed types within South Africa it was considered important to use methodologies that could reflect such differences and was developed under similar conditions. The methodology utilized is based on the Australian national greenhouse account’s National Inventory Report, which contains Australian country-specific and IPCC default methodologies and emission factors. Emission factors specific to South African conditions and management systems were calculated where possible. A Tier 2 approach was adopted for all major livestock categories including privately owned game in accordance with the IPCC Good Practice requirements. Recently game farming has become a recognized commercial enterprise in the agricultural sector which needs to be included as an anthropogenic emissions source. Methane emissions from South African livestock were estimated at 1328 Giga gram (Gg) during 2010. Dairy and beef cattle contributed an estimated 964 Gg or 72.6% of the total livestock methane emissions in South Africa during 2010. Beef cattle in extensive systems were the largest contributor (83.3%), followed by dairy cattle (13.5%), and feedlot cattle (3.2%). The estimated direct enteric methane emission factors for dairy and beef cattle were higher than the IPCC default factors for Africa. The Eastern Cape recorded the highest dairy and beef cattle methane emissions, whereas Gauteng showed the highest feedlot methane emissions primarily due to cattle numbers. Small stock was responsible for 15.6% of the total livestock emissions contributing an estimated 207.7 Gg, with sheep producing 167 Gg and goats producing 40.7 Gg. Calculated enteric methane emission factors for both commercial and communal sheep were higher than the IPCC default values for developing countries. A similar tendency was found with goat emission factors. The highest sheep and goat methane emissions were reported for the Eastern Cape province. The pig and ostrich industry both contributed approximately 8 Gg CH4 during 2010. The North- West province produced the highest commercial pig GHG emissions with the highest communal pig emissions originating from the Eastern Cape. The poultry industry was the largest direct N2O producer of the non-ruminant livestock industries, contributing 2.3 Gg or 92.8% of the total nonruminant N2O emissions. The privately owned game industry contributed an estimated 131.9 Gg of methane emissions with the provinces of Limpopo, Eastern Cape and Northern Cape being the three largest contributors with 43.4, 37.3 and 21 Gg methane, respectively. The total privately owned game population was estimated at 2 991 370 animals, utilizing 20.5 million hectares. Beef cattle are the major contributors to livestock GHG emissions in South Africa followed by sheep, privately owned game, dairy cattle, goats, pigs, ostriches, equine, and poultry. The IPCC default values for Africa underestimate emission factors across all livestock categories. The methane emission factors calculated for commercial livestock production systems are more comparable to emission factors from developed countries and the emerging/communal production systems to those of developing countries. This emphasizes the need to develop country-specific emission factors through quantitative research for livestock in all provinces and on all types of production systems to produce accurate baseline figures, which is critical to future mitigation protocols. As part of this study fourteen tropical grass species typical of transitional rangeland regions of South Africa were characterised in terms of chemical composition, in vitro total gas and in vitro methane production. The results of the study demonstrated that in vitro methane production varied between tropical grass species typical of transitional rangeland in South Africa. The variation between species allows for the potential to identify and select species with a lower enteric methane production potential. Panicum maximum, Eragrostis curvula and Elionurus miticus were the three species which produced the lowest in vitro methane production but which also had a crude protein (CP) concentration of more than 3.5% of dry matter (DM) and with an in vitro organic matter digestibility (IVOMD) above the group average for the study. Furthermore, the results of the study revealed that in vitro methane production was higher in Decreaser species compared to Increaser species. Improving the quality of available forages through the use of cultivated pastures and fertilization is known to improve ruminant production efficiency. The effect of level of nitrogen (N) fertilization on certain qualitative parameters and in vitro total gas and methane production of improved grass species commonly utilised in South Africa was evaluated. Treatments included seven grass species divided into two photosynthetic pathways (C3 and C4) with three levels of N fertilization (0, 50 and 100 kg N/ha). No effect was found for N fertilization on in vitro total gas or methane production. The CP concentration increased (P < 0.05) and the NDF concentration tended to decrease (P < 0.1) as the level of N fertilization increased for both C3 and C4 species. Increasing the level of N fertiliser increased (P < 0.05) the methanogenic potential of Dactylis glomorata, Festuca arundinacea and Cenchrus ciliaris after the 24 hour incubation period but no effects (P>0.05) were found after the 48 hour incubation period. Results suggests that the stage of physiological development of forages might have a greater influence on the methanogenic potential of forages compared to the effect of N fertiliser application.<br>Thesis (PhD)--University of Pretoria, 2017.<br>Animal and Wildlife Sciences<br>PhD<br>Unrestricted

Dissertação de Mestrado Integrado em Medicina Veterinária<br>Coccidiose é uma parasitose causadas por parasitas da subclasse Coccidia. No entanto, o termo é utilizado, maioritariamente, para referir parasitoses causadas por parasitas do género Eimeria, tal como ocorreu ao longo desta dissertação. Existe um grande número de espécies de Eimeria, estas apresentam grande especificidade em relação ao hospedeiro. A patogenicidade depende da espécie e poucas são consideradas suficientemente patogénicas, para que, por si só, desencadeiem manifestações clínicas da doença. Geralmente as infecções envolvem várias espécies. É uma doença intestinal que normalmente assume uma forma insidiosa e só se torna evidente nos animais infectados após o aparecimento de sinais clínicos como diarreia, debilidade, inaptência ou perda de peso, provocando grandes perdas económicas em todo o mundo. Tem o seu maior impacto em borregos com menos de três meses de idade e é comum em cabritos nos primeiros seis meses. É mais comum em sistemas de produção intensiva, sendo influenciada por vários factores, entre os quais, e o mais importante, o maneio praticado na exploração. E. crandallis e E. ovinoidalis são consideradas as espécies mais patogénicas em ovinos e em caprinos é a E. ninakohlyakimovae. Durante o período de estágio foram realizados dois estudos. O primeiro estudo pretendeu avaliar a prevalência de Eimeria spp. em explorações portuguesas de ovinos em regime extensivo, semi-intensivo e intensivo, seleccionadas por métodos não probabilísticos. Neste estudo verificou-se que os sistemas intensivos apresentavam maior percentagem de animais infectados, infecções do tipo misto eram mais prevalentes em explorações extensivas e infecções simples em explorações intensivas. E. bakuensis foi a espécie mais prevalente nos três sistemas de produção. E. ovinoidalis, uma das espécies mais patogénicas, foi mais frequente em explorações intensivas. O segundo estudo realizado pretendeu analisar o nível de excreção de oocistos de Eimeria spp. em cabritos entre as três e as treze semanas de vida em dois sistemas de produção distintos (uma exploração localizava-se em Portel e outra na Igrejinha), sendo que, em Portel os cabritos eram amamentados pelas fêmeas aleitantes e na Igrejinha eram amamentados artificialmente. Os resultados revelaram que E. caprina e E. christenseni apresentaram valores médios de excreção de oocistos superiores na exploração de Portel. O total médio de excreção de oocistos de Eimeria spp. atingiu o valor mais elevado às treze semanas, idade em que as espécies E. arloingi, E. caprina, E.caprovina, E. christenseni e E. hirci apresentaram os valores médios de excreção de oocistos mais elevados. Entre as quais, E. arloingi apresentou o valor mais elevado.<br>ABSTRACT - Coccidiosis in small ruminants Coccidiosis is a parasitism caused by parasites of the subclass Coccidia. Nevertheless, the term is used, generally, to refer to parasitism caused by parasites of the genre EimeriaThere is a great number of species of Eimeria which present a great host specificity. The pathogenecity depends on the species and few are considered pathogenic enough to, just for themselves, cause clinical manifestations of the disease. However the infections usually involve several species and regularly assumes a subtle form that only becomes evident in the infected animals after the occurrence of clinical signs, such as diarrhea, debility and weight loss, leading to important economical losses. Coccidiosis has its bigger impact in lambs with less than three months of age and it is common in goat kids in the first six months. It is more common in intense production systems, being influenced by many aspects, amongst which, and most important, the handling practiced in the explorations. E. crandallis and E. ovinoidalis are considered the more pathogenic species in sheep and in goats it is E. ninakohlyakimovae. Two studies were carried out during the training period. The first one had the purpose of evaluating the prevalence of Eimeria spp. in Portuguese sheep farms in extensive, semi-intensive and intensive systems, selected by non probabilistic methods. In this study it was concluded that the intensive systems presented a higher percentage of infected animals, being the single infections more frequent in intensive explorations and mixed infections more frequent in the extensive ones. E. bakuensis was the prevalent species in the three systems of production. E. ovinoidalis, one of the more pathogenic species, was more frequent in intensive explorations. The second study pretended to analyze the level of excretion of oocistos of Eimeria spp in kids between three and thirteen weeks of life in two distinct systems of production (in Portel and in Igrejinha), In the Portel farm the kids were fed by their dams and in the Igrejinha farm they were fed artificially. The results showed that E. caprina and E. christenseni presented excretion values of oocistos, superior in the Portel exploration. The total Eimeria spp. oocysts excretion excretion reached the maximum value at thirteen weeks, age in which E. arloingi, E. caprina, E.caprovina, E. christenseni and E. hirci reached the maximum medium values of excretion of oocyst. Amongst these, E. arloingi, presented the higher values.

The doubly labelled water technique (DLW) allows the estimation of the carbon dioxide production (r<SUB>co2</SUB>) of a free-living animal from which, with knowledge of the respiratory quotient (RQ), energy expenditure may be predicted. The aim of this project was to assess the performance of this technique in ruminant animals using sheep as a model. In a series of preliminary experiments physiological processes which may affect this technique were examined. It was found the administered isotopes equilibrated throughout the body water after 6 hours following either an oral or intravenous dosing. <SUP>2</SUP>H lost in the form of methane was estimated to lead to errors in r<SUB>co2</SUB> of between -3.27 and -6.54% and may be corrected for by use of a methane to urine enrichment ratio of 0.6536. Losses of <SUP>2</SUP>H in exchangeable sites in faeces were estimated to lead to errors in r<SUB>co2</SUB> of between -5.35 to -6.54%, again corrections factors were proposed. Sequestration of <SUP>2</SUP>H into carcase fat was also quantified, a maximum error of 0.67% was estimated on r<SUB>co2</SUB>, although more <SUP>2</SUP>H was detected in the fat free carcase this was assumed to be exchangeable <SUP>2</SUP>H. A maximum error of -2.39% on water turnover (r<SUB>H20</SUB>) was estimated to arise from the recycling of <SUP>2</SUP>H due to the catabolism of labelled body solids, although this was probably an overestimate. No convincing evidence was found to suggest the fractionation factors applied to human subjects are not equally applicable to ruminant animals. The baseline body water enrichment was altered by a change in diet from synthetic concentrates to fresh chopped grass. Isotopic estimates of r<SUB>co2</SUB> were compared with respiration chamber measurements of r<SUB>co2</SUB>. A number of curve fitting procedures were considered together with three multi-point, three ratio plot and three two-point estimations of r<SUB>co2</SUB>. Using a multi-point calculation and after making corrections for fractional water loss, loss of <SUP>2</SUP>H in methane and faecal solids, r<SUB>H20</SUB> was underestimated by 16.24%. The isotopic r<SUB>co2</SUB> estimates were on average 1.52% (SD 15.31) lower than the chamber measurements, although one animal was markedly different from the others, omitting this animal led to an average error of + 5.95% (SD 4.34). In applying this technique to animals in the field the influence of a free-living existence on the performance of the method was assessed. A number of r<SUB>co2</SUB> calculation procedures were again considered. Preliminary chamber measurements were used to estimate methane production and faecal dry matter output in the field. Estimates of r<SUB>H2O</SUB> in the field (mean 7.218.1. day<SUP>-1</SUP>) were lower than those measured in the chambers (mean 9.812 1.day<SUP>-1</SUP>). From predictions of dry matter intake in the field RQ was estimated (mean 1.067), using the isotopic r<SUB>co2</SUB> estimates (mean 590 1.day<SUP>-1</SUP>) energy expenditure was then predicted (mean 11586 kJ.day<SUP>-1</SUP>). In the light of this work it was concluded the DLW technique may be usefully applied to ruminant animals and a number of practical suggestions were made.

Made available in DSpace on 2015-03-26T13:55:12Z (GMT). No. of bitstreams: 1 texto completo.pdf: 240793 bytes, checksum: eeb362298c55405471ae4aeda1bb3acd (MD5) Previous issue date: 2012-07-18<br>Conselho Nacional de Desenvolvimento Científico e Tecnológico<br>This study aimed to evaluate the effects of the live yeast and inactive yeast autolyzed on the voluntary intake, digestibility coefficient, efficiency of microbial protein synthesis, characteristics of the ruminal environment - pH, volatile fatty acids (VFA), rumen ammonia nitrogen (RAN), and balance of nitrogen compounds of cattle feed with high concentrate levels. The experiment was carried out from November, 2010 to February, 2011. Five Nellore heifers with 300 kg ± 39.5 of initial body weight and fitted with rumen canullaes, were used and distributed in a 5 x 5 Latin square design, with five treatments, five animals and five experimental periods lasting 15 days. These 15 days were divided in seven days to the animal s adaptation and the other eight days were for the collection of data and materials. Five additives/levels in the same basal diet were evaluated, as follow: negative control (without additives); positive control (1% of the diet dry matter of sodium bicarbonate and magnesium oxide in the proportion of 4:1); live yeast (10 g/day); inactive yeast autolyzed in the doses of 15 and 30 g/day. The experimental diets consisted of two concentrates based on corn and soybean meal, that differed only by the presence or absence of sodium bicarbonate and magnesium oxide, containing 20% of corn silage, dry matter basis, and calculated to weight gain of 1.2 kg per animal per day, second NRC (2000). The use of additives didn t alter (P>0.05) dry matter intake (DM), and intake of organic matter (OM), crude protein (CP), ether extract (EE), neutral detergent fiber corrected for ash and nitrogenous compounds (NDFap), non-fiber carbohydrates (NFC) and total digestible nutrients (TDN). Only the EE digestibility coefficient was influenced (P<0.05) by the treatments, showing higher values to the treatments positive control and inactive yeast autolyzed in the dose of 30 g/day; the negative control was the treatment that presented the lower EE digestibility coefficient; the treatments inactive yeast autolyzed in the dose of 15 g/day and live yeast didn t differ from the others. The digestibility coefficient of DM, OM, CP, NDFap, NFC and the content of TDN were not affected (P>0.05) by the treatments. Effects were not detected (P>0.05) among treatments on the nitrogen intake, fecal nitrogen excretion, urinary excretion of nitrogen, balance of nitrogen compounds, nitrogen utilization efficiency in relation to N intake and to N absorbed and efficiency of microbial protein synthesis. There were no treatments effects (P>0.05) on the ruminal pH average, RAN, total production and molar ratio of VFA and in the ratio acetate:propionate. The evaluated blood metabolites, glucose, creatinin and urea, were not influenced (P>0.05) by the studied additives.<br>Objetivou-se investigar o efeito da levedura viva e levedura inativa autolisada sobre consumo voluntário, coeficientes de digestibilidade, eficiência de produção de proteína microbiana, características do ambiente ruminal - pH, nitrogênio amoniacal ruminal (NAR), ácidos graxos voláteis (AGV) e balanço de compostos nitrogenados de bovinos alimentados com dietas de alto concentrado. O experimento foi conduzido entre novembro de 2010 e fevereiro de 2011. Foram utilizadas cinco novilhas Nelore, de aproximadamente dois anos de idade, com peso corporal médio inicial de 300 ± 39,4 kg, fistuladas no rúmen, distribuídas em delineamento em quadrado latino 5 x 5, com cinco tratamentos e cinco períodos com 15 dias de duração. Destes 15 dias, sete foram destinados à adaptação dos animais e os oito dias restantes para realização de coletas de dados e material.. Avaliou-se cinco diferentes aditivos/níveis em uma mesma dieta basal: controle negativo (sem aditivos); controle positivo (bicarbonato de sódio e óxido de magnésio na proporção de 4:1 da matéria seca da dieta); levedura viva na dose de 10 g/animal/dia e levedura inativa autolisada nas doses de 15 e 30 g/animal/dia. As dietas experimentais consistiram de dois concentrados à base de milho e farelo de soja, que diferiam entre si somente pela presença ou não de bicarbonato de sódio e óxido de magnésio, contendo 20% de silagem de milho, base da matéria seca e calculada para proporcionar ganho de peso de 1,2 kg/animal/dia, segundo o NRC (2000). O uso de aditivos não alterou (P>0,05) o consumo de matéria seca (MS), matéria orgânica (MO), proteína bruta (PB), extrato etéreo (EE), fibra em detergente neutro corrigida para cinzas e proteína (FDNcp), carboidratos não fibrosos (CNF) e nutrientes digestíveis totais (NDT). Somente o coeficiente de digestibilidade (CD) do EE foi influenciado (P<0,05) pelos tratamentos, apresentando maiores valores para os tratamentos controle positivo e levedura autolisada na dose de 30 g/dia; o controle negativo foi o tratamento que apresentou a digestibilidade do EE mais baixa; os tratamentos levedura autolisada na dose de 15 g/dia e levedura viva não diferiram estatisticamente dos anteriores. Os demais CD, CDMS, CDMO, CDPB, CDFDNcp, CDCNF e o teor de NDT não foram afetados (P>0,05) pelos tratamentos. Não foram detectados efeitos (P>0,05) dos tratamentos sobre o consumo de nitrogênio, excreção fecal de nitrogênio, excreção urinária de nitrogênio, balanço de compostos nitrogenados, eficiência de utilização do nitrogênio em relação ao nitrogênio consumido e ao nitrogênio absorvido e eficiência de produção microbiana. Os tratamentos não influenciaram (P>0,05) a média do pH ruminal, a concentração de NAR, a produção total e proporções molares de AGV e a relação acetato:propionato. Os metabólitos sanguíneos avaliados, glicose, creatinina e ureia, não foram influenciados (P>0,05) pelos aditivos estudados.

Les enquetes, menees aupres de 361 exploitations de la somalie centrale et de 131 concessions du yatenga, ont permis d'etablir une typologie des unites de production agro-pastorales. Les performances des petits ruminants somaliens sont significativement liees aux conditions climatiques: l'age a la premiere parturition est superieur a deux ans; l'intervalle de mise-bas avoisine 14 mois; la fecondite est faible: 62% chez les ovins et 65% chez les caprins; la mortalite est elevee chez les jeunes animaux avant sevrage (13 a 51%). Les releves barymetriques et la description des robes (4653 animaux) ont permis la caracterisation des populations ovines et caprines. Chez les ovins et les caprins mossi et peul, les parametres zootechniques sont les suivants: l'age a la premiere parturition est de 15,0 mois chez les mossi, et de 13,9 et 14,7 mois chez les ovins et caprins peul; l'intervalle de mise-bas est de 9,4 et 9,5 mois chez les deux especes mossi et de 9,6 et 10,9 mois chez les brebis et chevres peul; le taux de reproduction annuel est de 1,36 et 1,51 chez les petits ruminants mossi et 1,33 et 1,7 chez les brebis et chevres peul; le taux de mortalite atteint 17,1% chez les agneaux et 20,6% chez les chevreaux. L'evolution des donnees ponderales et les effets des facteurs de variations sont analyses et discutes. Les resultats de la simulation demographique et economique confirment l'augmentation sensible de revenu net par reproductrice grace a la mise en uvre des techniques suivantes: plan de prophylaxie, enrichissement des sous-produits de recoltes a l'uree, supplementation minerale, embouche intensive des jeunes ovins males, choix des reproducteurs, controle de l'abreuvement. Les structures de developpement, capables de gerer ces techniques nouvelles, pourraient etre des associations de paysans ou d'eleveurs

Les viandes d’agneaux et de chevreaux sont une composante de l’identité des systèmes d’élevage de petits ruminants en méditerranée. Ces productions répondent souvent au qualificatif de « coproduit », c’est-à-dire dérivés d’une activité principale orientée par un autre produit avec lequel ils entretiennent une relation d’interdépendance. Leur histoire est pourtant celle de leur effacement, lié à une sectorisation des activités et un processus de découplage entre productions. Notre approche repose sur une analyse comparative entre différentes situations où produits dominants et coproduits sont en tension. Les couples étudiés concernent : i) en Corse, les fromages vs les agneaux de lait et les cabris de lait, ii) en Sardaigne, les fromages vs les agneaux et iii) au Maroc, l’huile d’argan vs le chevreau de l’Arganeraie.Depuis des situations initiales montrant une complémentarité entre les diverses productions d’un même système productif, sont progressivement apparues des concurrences autour de l’usage des ressources laitières ou forestières. Leur appropriation par un produit phare, inscrit dans une logique de spécification (fromage, huile d’argan) puis validé par une indication géographique, a marginalisé les coproduits dans leurs conditions de production et de valorisation. J’ai donc analysé les interactions entre productions interdépendantes au sein d’un même système productif, en focalisant sur l’incidence de la qualification d’un produit phare sur le devenir de son coproduit.Ce travail est une contribution à la géographie agricole centrée sur les relations entre production et territoire, en lien avec le fonctionnement des systèmes productifs. Son originalité réside dans l’échelle d’analyse qui comprend plusieurs produits liés entre eux dans un système productif. L’enjeu a été d’interroger la qualité comme vectrice de frontières sociales et techniques qui peuvent être sources d’exclusions si l’on examine le devenir des coproduits. La reconnaissance d’un produit phare, donnée pour participer à la confortation du territoire, peut contribuer à défaire les liens qui unissent les éléments du système productif et ainsi affaiblir le territoire. Les perspectives ouvertes par mes résultats portent sur la production de territoires multi-situés, dépassant les territorialités classiques construites selon des logiques institutionnelles (indication géographique isolant un produit du reste de son système productif) pour aller vers des fonctionnalités plurielles et imbriquées. En étudiant les relances de coproduits, j’ai pu comprendre les tiraillements autour de l’usage des ressources partagées, les rivalités et conflits, mais aussi les compromis qui peuvent en résulter et participer à des processus de recouplage dans des perspectives de multifonctionnalité<br>Lamb and kid meats are part of the identity of the livestock farming systems of small ruminants in Mediterranean area. But these meats are often qualified as “co-products”, that is to say issued from a main activity dedicated to another product they are linked with by interdependency. Therefore, their history is marked by a progressive disappearance due to the sectorisation of the activities and a decoupling of productions. Our research is based upon a comparative analysis between several situations where a dominant product and its co-product are under tension. The studied couples are: i) in Corsica island, cheeses and milk lambs and kids, ii) in Sardinia island, cheeses and lambs and iii) in Morocco, argan oil and arganian forest kids.From the initial situations showing complementarities between the various productions within a same productive system, we observe a progressive competition around the use of some dairy or forestry resources. The appropriation of such resources by a major product, engaged in a movement of specification (cheese, argan oil) validated by the recognition as geographical indication, marginalized the co-products (lamb and kid meats) weakening their conditions of elaboration and marketing. Thus, I analyzed the interactions between interdependent productions within a same productive system, focusing on the consequences of the recognition of a major product on the future of its co-product.The results are contributing to agrarian geography as a discipline centered on the relationships between production and territory, clarifying the way of functioning of the productive systems. The originality of this work lies on the scale of analysis gathering several products linked together within a productive system. One main stake has been to question the meaning of “quality” as driving social and technical boundaries that become, as general requirements, potential sources of exclusions according to the future of the co-products. The fact to recognize a major product, considered as participating to strengthen the territory, may induce the destruction of the links unifying the elements of the productive system and, by the way, weaken the territory. Such results open perspectives on the production of multi-situated territories, overcoming the classical way to consider this production under institutional logics (ie geographical indication isolating one product from its whole system) for designing plural and interlinked functionalities. Through the study of co-products involved into processes of recovery, I achieved understanding the frictions created around the uses of shared resources, rivalries and conflicts, but also possible resulting compromises that may contribute to processes of recoupling with perspectives of multi-functionality

Cette thèse avait pour objectif d'évaluer la défaunation comme technique permettant une meilleure nutrition des ruminants. La défaunation entraîne une augmentation du flux d'azote (non ammoniacal) au niveau du duodénum. Cependant, des études de la littérature indiquent que l'effet de la défaunation sur les productions animales (viande, lait et laine) est variable. Notre hypothèse de travail est que le rapport azote / énergie (PDIN / UF) de la ration est le principal facteur de variation des effets observés. Nous avions pour objectifs: 1) Etablir les lois de la réponse animale à la défaunation en général, ainsi que dans le contexte spécifique de la zone tropicale humide. 2) Déterminer l'impact de la défaunation sur les paramètres de la digestion permettant d'expliquer la réponse animale à la défaunation, notamment sur la protéosynthèse et la cellulolyse microbienne. En premier lieu, les lois générales des effets de la défaunation ont été établies à partir de l'analyse statistique d'une base de données de la littérature (méta-analyse). Dans un second temps, l'étude de quatre rations à base de fourrage (Digitaria decumbens) contenant 50, 60, 70 et 90 g PDIN /UF a été réalisée. Dans une seconde étude, quatre autres rations composées de fourrage avec complément (maïs et tourteau de soja) et contenant 80, 100, 120 et 140 g PDIN /UF, furent testées. La production de viande a été déterminée par mesures de gain de croît moyen quotidien (GMQ) d' agneaux faunés et défaunés, en fonction des huit profils alimentaires (8 rapports PDIN /UF). Des mesures de flux duodénaux d'azote sur des béliers adultes fistulés, faunés et défaunés, nous ont permis d'estimer la protéosynthèse. La cellulolyse microbienne a été estimé par les mesures de dégradabilité in sacco des fibres (NDF), de digestibilité ruminale des fibres (NDF) ainsi que par la mesure des activités enzymatiques glycolytiques du rumen, sur ces mêmes béliers. Les résultats de la synthèse bibliographique indiquent que la défaunation entraîne une augmentation de la croissance des animaux en moyenne de 10% (P < 0.01, 132.6 vs 118.7 ± 5.2 g/j). Lors des essais expérimentaux, la défaunation a permis d'augmenter le GMQ en moyenne avec les rations mixtes ( PDIN / UF > 80) (P < 0.03, 184.1 vs 165.9 ± 9.3 g/j). Aucun effet n'a été observé pour les rations de fourrage (GMQ = 76 ± 3 g/j), sauf pour la ration contenant 50 PDIN/UF (25 vs 49 ± 11 g/j). Dans la synthèse bibliographique, l'augmentation de 20 % du flux d'azote (microbien et alimentaire) intestinal après défaunation, contribue à l'augmentation des quantités de nutriments azotés absorbés. Pour les études expérimentales, après défaunation ce flux augmente significativement de 20% pour les rations mixtes, et de (+ 11%) pour la ration de fourrage. La synthèse indique une amélioration du profil des acides gras volatils (AGV) du rumen (augmentation du pourcentage de propionate) après defaunation, tandis que la cellulolyse microbienne diminue (- 4.7 % DrNDF). L'augmentation du flux d'azote intestinal et l'amélioration du profil des AGV contribuent à l'amélioration de l'utilisation métabolique des nutriments énergétiques. Ainsi, la défaunation améliore l'indice de consommation des animaux défaunés ( -1.4 g MS / g de croît). L'ensemble de ces résultats est confirmé par l'étude de nos rations expérimentales. En conclusion, le rapport azote / énergie de la ration module les effets de la défaunation, quand l'énergie n'est pas limitante. En zone tropicale humide, la défaunation ne présenterait un intérêt que pour les rations mixtes et les vieux fourrages. L'intérêt de la défaunation en ZTH reste à confirmer, notamment pour les jeunes fourrages et la canne à sucre (pauvre en azote, riche en sucre).

Made available in DSpace on 2015-03-26T13:55:11Z (GMT). No. of bitstreams: 1 texto completo.pdf: 957474 bytes, checksum: 77cf971e8dacf24949def2ed6c79c3c2 (MD5) Previous issue date: 2011-07-15<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>The gradual growth of the biodiesel participation in global energy production creates a need for studies on the use of co-products generated in this production chain in animal feed, especially for small ruminants. In this sense, it is proposed to evaluate the co-product of oil extraction of castor seeds (Ricinus communis), castor bean meal (CM) in diets for sheep. In the experiment we evaluated the use of castor bean meal treated with 60 g/kg of calcium oxide (CaO), provided, dry or humid, on consumption and digestibility, performance, nitrogen balance and liver function in lambs. The CM was obtained after extraction of oil from castor beans using organic solvent. The treatment was performed using the CM solution of calcium oxide (CaO), prepared by diluting each kg in 10 liters of water. After mixing this solution to the CM, it remained at rest for 18 hours, and part of it dry in the yard and part of cement supplied after the period of disregard for the animals. The study included 35 male lambs, not neutered, mixed breed with average initial weight of 20 ± 0.253 kg kept in individual cages for 85 days, 15 days of adaptation and 70 days for data collection. The animals were randomly assigned to five treatments, arranged in a 2 x 2 +1 factorial, with two levels of substitution of soybean meal by castor meal (50 and 100%) and two forms of delivery of the castor bean meal (dry or humid) and a control treatment to the base of soybean meal. The diet was composed of 60% corn silage and 40% concentrate (based on MS) and isonitrogenous, with 15% CP (DM basis) in order to meet the nutritional requirements of a sheep with 20 kg body weight and average daily gain of 200 g. There was no significant interaction (P> 0.05) between the level of substitution of CM by soybean meal and the type of treated castor meal (dry or humid) to any of the characteristics evaluated in this experiment. DM intake and nutrient (P> 0.05), except crude protein (CP) and non-fiber carbohydrates (NFC) (P <0.05), when expressed in g / kgPC did not differ between treatments. The digestibility of DM, organic matter (OM), ether extract (EE), neutral detergent soluble fiber corrected for ash and protein (NDFap), and TDN did not differ (P> 0.05) between treatments. However, it was observed a quadratic effect on the digestibility of NFC (P = 0.015). The final body weight (PVF), average daily gain (ADG), the hot carcass weight (HCW), cold carcass weight (CCW) and cold carcass yield (RCF), did not differ between treatments evaluated (P > 0.05). However, there was a quadratic effect (P = 0.041) for hot carcass yield (WHR), when the SM was replaced by CM, with maximum at 45.66% substitution. Similar behavior was observed for the cooling losses also with a quadratic effect (P <0.001), due to the replacement level by the SM and CM humid or dry (P = 0.041). There was no difference in nitrogen intake (NI) (P> 0.05). The fecal nitrogen (FN) when presented in g / day (P> 0.05) showed no difference. However, when presented as% of N intake showed a linear effect due to the increased level of substitution of CM by SM (P = 0.050) and CM (P = 0.045). N excretion via urine showed a quadratic effect (P = 0.002), with increased excretion of N in the treatments with 50% substitution. The quadratic effect of N excretion via urine also reflected in urinary urea (P = 0.016) and (P <0.001). Serum levels of enzymes related to liver function did not change. We conclude that it is possible to replace all or part of soybean meal by meal castor treated with calcium oxide sputtered in dry or wet forms, in the diet of sheep in confinement, when fed to the level of 18% of total DM.<br>O crescimento gradual da participação do biodiesel na matriz energética mundial cria necessidade de estudos sobre a utilização dos co-produtos gerados nesta cadeia produtiva na alimentação animal, sobretudo para pequenos ruminantes. Neste sentido, propõe-se avaliar o co-produto da extração de óleo de sementes de mamona (Ricinus communis), farelo de mamona (FM), na alimentação de ovinos. No experimento avaliou-se o uso do farelo de mamona tratado com 60g de (CaO)/kg, fornecido, seco ou úmido, sobre o consumo e digestibilidade, desempenho, balanço de nitrogênio e função hepática em cordeiros. O FM foi obtido após extração do óleo de sementes de mamona utilizando-se solvente orgânico. O tratamento do FM foi realizado utilizando solução de óxido de cálcio (CaO), preparada diluindo-se cada kg em 10 litros de água. Após a mistura desta solução ao FM, este permaneceu em repouso por 18 horas, sendo parte do mesmo seco em terreiro de cimento e parte fornecido após o período de descaso para os animais. Foram utilizados 35 cordeiros machos, deslanados, não castrados, sem raça definida com peso inicial médio de 20 ± 0,253 kg mantidos em gaiolas individuais por 85 dias, sendo 15 dias de adaptação e 70 dias para coleta de dados. Os animais foram distribuídos aleatoriamente em cinco tratamentos, arranjados em esquema fatorial 2x2+1, sendo dois níveis de substituição ao farelo de soja pelo farelo de mamona (50 e 100%) e duas formas de fornecimento do farelo de mamona (seco ou úmido) e um tratamento controle à base do farelo de soja. A dieta foi composta por 60% de silagem de milho e 40% de concentrado (na base MS), sendo isonitrogenadas, com 15% de PB (base da MS), de forma a atender as exigências nutricionais de um ovino com 20 kg de peso corporal e ganho médio diário de 200 g. Não se observou interação (P>0,05) entre o nível de substituição do FS pelo FM e o tipo de farelo de mamona tratado (seco ou úmido) para nenhuma das características avaliadas neste experimento. O consumo de MS e dos nutrientes (P>0,05), exceto proteína bruta (PB) e carboidratos não fibrosos (CNF) (P<0,05), quando expressos em g/kgPC, não diferiu entre os tratamentos. A digestibilidade da MS, matéria orgânica (MO), extrato etéreo (EE), fibra solúvel em detergente neutro corrigida para cinza e proteína (FDNcp), e NDT não diferiu (P>0,05) entre os tratamentos avaliados. No entanto, foi observado efeito quadrático sobre a digestibilidade do CNF (P=0,015). O peso vivo final (PVF), o ganho médio diário (GMD), o peso de carcaça quente (PCQ), o peso de carcaça fria (PCF) e o rendimento de carcaça fria (RCF), não diferiram entre os tratamentos avaliados (P>0,05). No entanto, observa-se efeito quadrático (P=0,041) para o rendimento de carcaça quente (RCQ), quando o FS foi substituído pelo FMTU, com ponto máximo em 45,66% de substituição. Comportamento semelhante foi observado para as perdas por resfriamento (PR), também com efeito quadrático (P<0,001), em função do nível de substituição do FS pelo FMTS e FMTU (P=0,041). Não foi encontrada diferença no nitrogênio ingerido (NI) (P>0,05). O nitrogênio fecal (NF) quando apresentado em g/dia (P>0.05) não apresentou diferença. Porém, quando apresentado em % do N ingerido apresentou efeito linear negativo em função do aumento do nível de substituição do FS pelo FMTS (P=0,050) e FMTU (P=0,045). A excreção de N via urina apresentou efeito quadrático (P=0,002), com maior excreção de N nos tratamentos com 50% de substituição. O efeito quadrático na excreção de N via urina também refletiu na excreção urinária de uréia (P=0,016) e (P<0,001). Os níveis séricos de enzimas relacionadas com função hepática não se alteraram. Conclui-se que é possível a substituição total ou parcial do farelo de soja pelo farelo de mamona tratado com óxido de cálcio micropulverizada, nas formas seca ou úmida, na dieta de ovinos em confinamento, quando alimentados até o nível de 18% da MS total.

Thesis (Ph. D.) -- University of Maryland, College Park, 2006.<br>Thesis research directed by: Animal Sciences. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

<p> Animals with multi-compartmented stomachs, also known as ruminants, are adapted to digest cellulosic materials, which constitute the primary expense on ranches and dairies. Industrial byproducts can be repurposed for livestock diets to decrease these costs. Therefore, finding alternative feedstuffs may benefit the economics of livestock production. The goal of this project was to evaluate alternative uses of ruminal waste from commercial abattoirs. This project addressed two primary objectives. First, ruminal fiber as a potential dietary fiber source was evaluated. Second, the potential for preservation of ruminal fluid for later use was assessed. Results for the first objective indicated harvesting rumen waste from slaughterhouses could be beneficial for sustainable livestock production, while reducing the environmental threat posed by disposal of ruminal waste. Nutritional values of rumen waste in relation to other common livestock roughages sources commonly found in ruminant diets are numberical , such as coastal Bermuda grass hay (<i>Cynodon dactylon </i>) and alfalfa hay (<i>Medicago sativa</i>). Neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL) and crude protein (CP) values were 68.1%, 39.9%, 10.9% and 15%, respectively. Contribution to variance for NDF, ADF, ADL and CP were 97.2%, 97.9%, 95.4% and 19.1%, respectively. <i> In vitro</i> true digestibility (IVTD) and <i>in vitro</i> neutral detergent fiber digestibility (IVNDFD) were 46.2% and 21.6%, respectively. Results from the second objective showed lower degradation of feeds when frozen or lyophilized rumen fluid was used rather than fresh inoculum; however, differences in IVTD and IVNDFD suggest that, in the absence of fresh inocula, preserved rumen fluid may be a viable option. Implications from this study show rumen content could provide nutrients if fed to livestock and rumen microbes preserved (frozen or lyophilized) are still viable and able to degrade feedstuffs. Therefore, further research is needed to assess the consistency of using inoculum from slaughtered cattle and improve the preservation process.</p><p>

The influence of microbial activity on the pattern of gas production and the possibility of developing a protocol for standardising the microbial activity of ruminal fluid were investigated (chapter 2). Firstly, ruminal fluid was diluted 1:2, 1:5, 1:9 and 1:20 (v/v) with buffer solution and the <i>in vitro</i> gas production from cellulose, glucose, hay and ryegrass studied. Gas production at 4, 24 and 120h were significantly decreased as the ratio of buffer solution to ruminal fluid increased. For each substrate, incubation with ruminal fluid diluted 1:2 (v/v) gave a higher (P<<i>0.5</i>) asymptotic value 'B', rate 'C' of gas production and lower lag time than when incubated in the 1:5, 1:9 and 1:20 dilutions. Secondly, the effect of frequency of ovine ruminal sampling on microbial activity and substrate fermentation was investigated. The bacterial DM, bacterial absorbance and blank's gas volume were significantly affected by daily sampling of ruminal fluid. Daily sampling of rumen fluid did not significantly affect the gas production degradability parameters (B,C and Lag) until the bacterial DM fell below 0.09 g DM/10 cm³ strained rumen fluid. Bacterial DM was strongly related to the absorbance of ruminal fluid (R² = 0.99, <i>p</i><0.001), suggesting that standardisation of the level of microbial activity between days and laboratory can be achieved by estimating the bacterial DM from the absorbance of the strained ruminal fluid. The influence of donor diet on initial microbial concentration and gas production degradability was studied (chapter 3). Bacterial DM, bacterial absorbance and the blanks' gas volume increased significantly as the ratio of sheep pellet to hay increased. The gas production degradability parameters (B, C and Lag) were also affected by changing the donor diet ratio of sheep pellets and hay. NDF digestibility of cellulose and hay was not significantly affected by donor diet. Bacterial DM was strongly related to the absorbance of ruminal fluid and the blanks' gas volume (R² = 0.99, <i>p</i><0.001). These results suggest that changing the ratio of concentrate to hay reduced the initial bacterial concentration and affected the gas production degradability parameters.

Le méthane (CH4) est un des principaux gaz à effet de serre. L'élevage est à l'origine d'un tiers du CH4 produit par l'activité humaine en Europe. En plus, la production de CH4 représente une perte de 2% à 12 % de l'énergie consommée par l'animal. La méthanogenèse est le résultat de l'activité d'un groupe de microorganismes particuliers - les Archaea méthanogènes. La production de CH4 permet de d'éliminer du milieu ruminal l'hydrogène produit au cours de la fermentation des aliments par les autres microorganismes (bactéries, protozoaires, champignons). En effet, l'accumulation d'hydrogène affecte le fonctionnement optimal du rumen. La réduction des émissions de CH4 par les ruminants présente donc un intérêt économique et environnemental non négligeable et passe inévitablement par une modification de l'écosystème microbien du rumen. L'objectif de ce travail de thèse était de relier la production de CH4 avec la structure et l'activité de la communauté méthanogène du rumen. Différents modèles de manipulation de l'écosystème microbien ruminal comme la défaunation (élimination des protozoaires) et l'utilisation d'aliments connus pour modifier la méthanogenèse ont été utilisés. Le rumen étant un écosystème complexe, les interactions fonctionnelles entre les Archaea méthanogènes et les autres microorganismes présents (bactéries et protozoaires) ont également été étudiées. Dans cette optique, des outils de biologie moléculaire, permettant de cibler les principales communautés microbiennes, ont été optimisés. Nos travaux permettent de conclure sur l'absence de relation claire entre le nombre (et/ou la concentration) des Archaea méthanogènes et la méthanogenèse dans le rumen. Cependant les réductions des émissions de CH4 ont été attribuées aux changements dans la diversité de la communauté méthanogène et la disponibilité en hydrogène. Ce travail de thèse a mis en évidence que les modifications de la composition et/ou de l'activité métabolique de la communauté des Archaea méthanogènes seraient à l'origine des réductions des émissions de CH4 par les ruminants. Une meilleure connaissance des mécanismes microbiens impliqués dans la production de méthane permettra d'envisager de nouvelles pistes pour diminuer les émissions chez les ruminants.

Made available in DSpace on 2015-03-26T13:55:14Z (GMT). No. of bitstreams: 1 texto completo.pdf: 605913 bytes, checksum: 567cf7b52ccdd329ffc64b287c636d4d (MD5) Previous issue date: 2012-10-29<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>This dissertation was prepared from data generated in two experiments with procedures for the in situ isolation of indigestible neutral detergent fiber (iNDF) and indigestible acid detergent fiber (iADF) using sheep. The first experiment aimed to determine the in situ incubation time needed for the isolation of iNDF, and investigate the occurrence of mineral contamination in long term incubations in sheep. Samples concentrates, roughages and faeces were used. All samples were ground through in a cutting mill utilizing sieve with pores of 2mm diameter. Subsequently, the samples were placed in 4 x 5 cm non-woven textile fabric (NWT - 100g / m²) bags at the rate of 20 mg of dry matter (DM) / cm ² of exposed area and incubated in the rumen of four male sheep. This procedure was repeated four times, and incubated at every period groups among animals. The following incubation times were used: 0, 12, 24, 48, 72, 96, 120, 144, 168, 192, 216, 240 and 312 hours. After the bags had been removed, the contents of neutral detergent fiber (NDF) and neutral detergent insoluble ash (NDIA) of the residues were analyzed. The NDF degradation profiles were interpreted independently for each material by a non-linear logistic model. The profiles of availability of mineral associated with undegraded NDF were interpreted by a asymptotic model of the first order. Incubation times in sheep of 168 hours are recommended for isolation of NDFi. The content of mineral associated with undegraded NDF stabilized on average 28,9 hours after incubation, showing that samples were not contaminated by mineral, beyond that naturally associated with NDF. In the second experiment, the objective was to evaluate the influence of concentrate level in the diet on the estimates of roughages iNDF and iADF, and, incubation time needed for the in situ isolation of these fractions in sheep. The following forages were used for in situ procedures: in natura sugarcane, Tifton 85 hay, corn straw and corn silage. The samples processing and packaging were carried out following the procedures used in the first experiment. The treatments consisted on diets with different roughage (R): concentrate (C) proportions: 100V: 0C; 80V: 20C, 60V: 40C, 40F: 60C. Treatments were assigned to four male sheep breed, rumen using a Latin square design 4 x 4. The same incubation times used in the first experiment were applied in this experiment. After removal of the bags, they had their NDF and ADF contents analyzed sequentially. The degradation profiles were initially interpreted individually for each forage in each treatment using a non-linear logistic model. For each incubated roughage, the adjusted models were compared to check the effect of treatments on the indigestible fractions (iNDF and iADF) estimates and the fiber degradation rate. It was observed treatment effect (P <0.05) on the iNDFi and iADF estimates for in natura sugarcane and corn silage. It was observed influence of the treatments (P <0.05) on the degradation rates of NDF and ADF to the four roughages It is recommended that for in situ procedures using sheep fed up to 20% concentrate, incubations times of 120 and 144 hours be used for isolation of iNDF and iADF, respectively.<br>Esta dissertação foi elaborada a partir de dados gerados em dois experimentos com procedimentos para o isolamento da fibra insolúvel em detergente neutro indigestível (FDNi) e fibra insolúvel em detergente ácido indigestível (FDAi) em procedimentos in situ em ovinos. No primeiro experimento, objetivou-se determinar o tempo de incubação in situ, necessário para o isolamento da FDNi e, investigar a ocorrência de contaminação mineral em amostras incubadas no rúmen de ovinos por longos períodos. Foram utilizadas amostras de alimentos concentrados, volumosos e fezes. Todas as amostras foram processadas em moinho de facas utilizando peneira com poros de 2 mm de diâmetro. Posteriormente, as amostras foram acondicionadas em sacos de tecido não tecido (TNT, gramatura 100g/m²) de dimensão igual a 4 x 5 cm, na proporção de 20 mg de matéria seca(MS)/cm² de superfície exposta e incubados no rúmen de quatro ovinos machos, sem raça definida, fistulados no rúmen. Tal procedimento foi repetido por quatro vezes, incubando-se a cada período os grupos em animais distintos. Utilizaram-se os tempos de incubação: 0, 12, 24, 48, 72, 96, 120, 144, 168, 192, 216, 240 e 312 horas. Após a retirada dos sacos, foram determinados os teores de FDN e cinzas insolúveis em detergente neutro (CIDN). Os perfis de degradação da FDN foram interpretados de forma independente para cada material por meio de modelo logístico não linear. Os perfis de disponibilização da CIDN foram interpretados por meio de modelo assintótico de primeira ordem. Recomenda-se tempo de incubação in situ em de 168 horas para isolamento da FDNi em ovinos. Os teores de CIDN dos resíduos não degradados estabilizaram-se em média 28,9 horas após a incubação, demonstrando que as amostras não apresentaram contaminação mineral além daquela naturalmente associada à FDN. No segundo experimento, objetivou-se avaliar a influência do nível de concentrado da dieta sobre as estimativas da FDNi e FDAi de alimentos volumosos e os tempos de incubação in situ necessários para o isolamento destas frações em ovinos. Foram utilizadas para os procedimentos in situ amostras dos alimentos: cana-de-açúcar in natura, feno de tifton 85, palha de milho e silagem de milho. O processamento e acondicionamento das amostras foram realizados seguindo os procedimentos utilizados no primeiro experimento. Os tratamentos constituíram-se de dietas com diferentes relações volumoso(V):concentrado(C): 100V:0C; 80V:20C; 60V:40C e 40V:60C. Os tratamentos foram designados a quatro ovinos machos, sem raça definida, fistulados no rúmen por meio de um delineamento quadrado latino 4 x 4. Utilizou-se os mesmos tempos de incubação utilizados no primeiro experimento. Após a retirada dos sacos, estes tiveram seus teores de FDN e FDA analisados de forma sequencial. Os perfis de degradação foram inicialmente interpretados de forma individual para cada alimento em cada tratamento através de modelo logístico não linear. Procedeuse, para cada alimento incubado, a comparação entre os modelos ajustados, de modo a verificar o efeito dos tratamentos sobre as estimativas das frações indigestíveis (FDNi e FDAi) e taxa relativa à dinâmica de degradação ruminal. Observou-se efeito de tratamento (P<0,05) sobre a estimativa da FDNi e FDAi da cana-de-açúcar e silagem de milho. Para todos os alimentos foi observada influência dos tratamentos (P<0,05) sobre as taxas de degradação da FDN e FDA. Recomenda-se, para procedimentos in situ, em ovinos alimentados com até 20% de concentrado, a utilização de incubações de 120 e 144 horas, para isolamento da FDNi e FDAi, respectivamente.

Made available in DSpace on 2015-03-26T13:55:19Z (GMT). No. of bitstreams: 1 texto completo.pdf: 265737 bytes, checksum: 7936c17fdb38c477d2312632a8b70d18 (MD5) Previous issue date: 2013-05-29<br>Conselho Nacional de Desenvolvimento Científico e Tecnológico<br>This study was conducted to evaluate the effects of the use of sugarcane silage or traditional sources of forage (corn silage or fresh sugarcane) for Holstein cows on intake, milk production and nutritional parameters. The experiment was conducted at the Unidade de Ensino, Pesquisa e Extensão em Gado de Leite do Departamento de Zootecnia (DZO), da Universidade Federal de Viçosa, between July and September 2011. We used 25 Holstein cows with 600 kg of weight body inicially and adopted the randomized block design (RBD) with 5 blocks, 5 periods lasting 14 days each and 5 treatments, in a repeated measures in time. The treatments were provided corn silage, fresh sugarcane, sugarcane silage pure, cane silage with 0.5% CaO and cane silage with Lactobacillus buchneri. The forage: concentrate ratio of 60:40 for the MS diet based on corn silage and 40:60 for diets with sugarcane. Data were subjected to analysis of variance using the mixed procedure of SAS being used orthogonal contrasts to compare means adopting the 5% level of significance. Intake (kg / day) of DM were similar between treatments. A higher intake (kg / day) of EE and NDF and higher digestibility of DM, OM, EE, NDF and TDN diet based on corn silage in relation to diets based on sugarcane. There was a higher digestibility of DM and OM in diet of sugarcane silage inoculated with L. buchneri than sugarcane silage inoculated with CaO and there was a higher digestibility of DM, OM, EE, NDF and TDN to silage additives relative to sugarcane pure silage. The production of milk, fat and solids not fat were similar among treatments. It was concluded that diets based on sugarcane ensiled with forage: concentrate ratio of 40:60 in DM provides up to 22 kg of milk / cow / day and does not alter the composition of milk.<br>Este trabalho foi desenvolvido para avaliar os efeitos da utilização da silagem de cana-de-açúcar ou fontes tradicionais de volumosos (silagem de milho ou cana-de-açúcar in natura) para vacas Holandesas sobre o consumo, produção de leite e parâmetros nutricionais. O experimento foi conduzido na Unidade de Ensino, Pesquisa e Extensão em Gado de Leite do Departamento de Zootecnia (DZO), na Universidade Federal de Viçosa, entre julho e setembro de 2011. Foram utilizadas 25 vacas da raça Holandesa, com peso médio inicial de 600 kg e adotado o delineamento em blocos casualizados, com 5 blocos, 5 períodos com duração de 14 dias cada e 5 tratamentos, em esquema de medidas repetidas no tempo. Os tratamentos fornecidos foram silagem de milho, cana-de-açúcar in natura, silagem de cana-de-açúcar pura, silagem de cana-de-açúcar com 0,5% de CaO e silagem de cana-de-açúcar com Lactobacillus buchneri. A relação volumoso:concentrado foi de 60:40 na MS para dieta à base de silagem de milho e 40:60 para dietas com cana-de-açúcar ou cana-de-açúcar ensilada. Os dados foram submetidos à análise de variância, utilizando-se o procedimento Mixed do programa SAS, sendo utilizados contrastes ortogonais para comparação de médias adotando-se o nível de 5% de significância. Os consumos (kg/dia) de MS foram semelhantes entre os tratamentos. Verificou-se maior consumo (Kg/dia) de EE e FDNcp e maiores coeficientes de digestibilidade da MS, MO, EE, FDNcp e NDT para a dieta à base de silagem de milho em relação às dietas à base de cana-deaçúcar. Observou-se maior coeficiente de digestibilidade da MS e MO para dieta à base de silagem de cana-de-açúcar inoculada com L. buchneri em relação à silagem com CaO e de MS, MO, EE, FDNcp e teor de NDT para silagem de cana aditivada em relação à silagem de cana-de-açúcar pura. A produção de leite, teores de gordura e extrato seco desengordurado foram semelhantes entre os tratamentos. Conclui-se que dietas à base de cana-deaçúcar ensilada, com relação volumoso:concentrado de 40:60 na MS, proporcionam produção de até 22 kg/dia e não alteram a composição do leite.

Kyoto University (京都大学)<br>0048<br>新制・課程博士<br>博士(農学)<br>甲第20434号<br>農博第2219号<br>新制||農||1049(附属図書館)<br>学位論文||H29||N5055(農学部図書室)<br>京都大学大学院農学研究科応用生物科学専攻<br>(主査)教授 廣岡 博之, 教授 松井 徹, 教授 久米 新一<br>学位規則第4条第1項該当

La composition du lait en acides gras (AG) chez la vache laitière est la résultante du métabolisme lipidique au niveau du rumen et au niveau de la glande mammaire. Dans le cadre du renouvellement des systèmes d’unités d’alimentation INRA, l’objectif de ce travail est de prédire par une approche quantitative utilisant la méta-analyse de bases de données, les flux duodénaux d’AG chez les ruminants, le transfert des AG de l’intestin à la glande mammaire, et les flux d’AG sécrétés dans le lait.Des équations de prédiction des flux duodénaux et absorbés des AG saturés, des AG impairs et ramifiés, et d’un grand nombre d’isomères des AG insaturés ont été obtenues en intégrant les effets de facteurs expérimentaux tels que la nature du fourrage, le pourcentage de concentré, la supplémentation en huiles, graines végétales, et en produits marins, et leurs interactions. Ces équations sont fonction des AG ingérés et des facteurs interférents (mode de conservation et familles botaniques des fourrages, composition du régime alimentaire, caractéristiques des animaux).Pour le transfert des AG du duodénum à la glande mammaire, les équations privilégient comme prédicteur leur flux duodénal respectif, mais utilisent aussi des paramètres digestifs ruminaux (pH, acétate, butyrate) ou des caractéristiques des rations pour les AG impairs et ramifiés, ou les AG synthétisés de novo (C4:0 à C14:0).La validation de ces modèles a été faite à partir d’une base de données externe qui a permis de coupler les deux modèles et d’évaluer leur précision. Finalement, nous proposons des équations de prédiction des AG spécifiques ainsi que des groupes d’AG présentant un intérêt nutritionnel et qui peuvent fournir une approche aux systèmes d'unités d'alimentation pour prédire leurs réponses à différents types de rations<br>Milk fatty acids (FA) composition in dairy cows results from lipid metabolism in rumen and mammary gland. In the context of renewing the INRA feed unit system, the objective of this work is to predict, by a quantitative approach using metaanalysis, duodenal flows of FA in ruminants, FA transfer from the intestine to the mammary gland, and the secreted FA flows in the milk. Predictive equations for duodenal and absorbed saturated FA, odd and branched FA, and a large number of unsaturated FA isomers were obtained by integrating the effects of experimental factors such as the nature of the forage, the concentrate percentage, supplementation with oleaginous oils and seeds, and marine products, and their interactions.These equations are function of ingested FA and their interfering factors (forage conservation mode and botanical family, diet composition, animal factors).For the transfer of FA from duodenum to the mammary gland, the equations favor the prediction of their respective duodenal flows, but they also use ruminal digestive parameters (pH, acetate, butyrate) or dietary characteristics for odd and branched FA, or de novo synthesized FA (C4 :0 to C14 :0).Models validation was done with an external database, which allowed coupling the two models and evaluate their accuracy. Finally, we propose predictive equations for specific FA as well as FA groups of nutritional interest that can provide an approach to the INRA feed unit system to predict their milk yield responses according to different types of rations