Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-10-16T12:11:58Z No. of bitstreams: 1 2016 - Cristiane Nunes Coelho da Rocha.pdf: 2134676 bytes, checksum: 7d111f5f6a4f012cde150c537673a52f (MD5) / Made available in DSpace on 2017-10-16T12:11:58Z (GMT). No. of bitstreams: 1 2016 - Cristiane Nunes Coelho da Rocha.pdf: 2134676 bytes, checksum: 7d111f5f6a4f012cde150c537673a52f (MD5) Previous issue date: 2016-03-21 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The purpose of the research was to evaluate the efficacy of association abamectin 0.6% with fluazuron 3.0% in control of Rhipicephalus microplus, Dermatobia hominis and gastrointestinal nematodes in cattle. For this, there were five tests in which the control group animals received no treatment, while animals in the treated group received the formulation within the association in a single dose of 600 mcg of abamectin and 3 mg of fluazuron per Kg of body weight by route ?pour-on?. As to acaricide efficacy, two tests were conducted, one using artificially infested cattle and other naturally infested by Rhipicephalus microplus. In the same manner, a test was conducted to evaluate the efficacy of the product in test front of Dermatobia hominis naturally infested cattle. And two tests anthelmintic efficacy in infected cattle naturally and artificially by gastrointestinal nematodes. The mean of the carrapaticide efficacy for cattle artificially infested with R. microplus over the 23 days after treatment was 87,40%. The preventive effectiveness results of 98,12%; 98,68%; 98,36%; 97,88%; 96,76%; 96,45%; 96,84%; 97,03%; 95,36% and 87,07% respectively for the experimental days +7, +14, +21, +28, +35, +42, +49, +56, +63, +70. The acaricide effectiveness for naturally infested cattle by R. microplus was 96,30%; 96,90%; 95,98%; 96,83%; 98,32%; 96,12%; 96,15%; 98,8%; 97,18%, 99,12%; 97,18%; 98,04% and 77,50%, respectively for the experimental days +7, +14, +21, +28, +35, +42, +49, +56, +63, +70, +77, +84 and +91 for the treated group. The efficacy of the test product to D. hominis was 90,70% and 96,84% for days +7 and +14. The values of anthelmintic efficacy in naturally infected cattle with gastrointestinal nematodes was 92,17%; 89,32%; 87,38% respectively for the experimental days +7, +14, +21 for the treated group. For cattle artificially infected by gastrointestinal nematodes the efficacy was 92,59%; 97,62%; 87,82%; 86,96%; 96,00% respectively for Haemonchus placei, Trichostrongylus axei, Cooperia punctata, Cooperia pectinata and Oesophagostomum radiatum. The association abamectin 0.6% with fluazuron 3.0% was effective in artificially infested cattle and naturally infested by R. microplus, as well as demonstrates efficacy for D. hominis. The test product showed efficacy also in the reduction the eggs counts per gram of feces (EPG) in cattle naturally infected with gastrointestinal nematodes, as well as shown to be effective front of artificial infections with H. placei, T. axei and O. radiatum and has presented moderately effective against C. pectinata and C. punctata / O objetivo da pesquisa foi avaliar a efic?cia da associa??o de abamectina 0.6% com fluazuron 3.0% controle de Rhipicephalus microplus, Dermatobia hominis e nemat?ides gastrointestinais em bovinos. Para isso, foram realizados cinco ensaios, nos quais os animais do grupo controle n?o receberam tratamento, enquanto que os animais do grupo tratado receberam a formula??o da associa??o na dose ?nica de 600 mcg de abamectina com 3 mg de fluazuron por Kg de peso corporal, por meio de via ?pour-on?. Quanto ? atividade carrapaticida, foram conduzidos dois ensaios, um utilizando bovinos artificialmente infestados e outro naturalmente infestados por Rhipicephalus microplus. Da mesma forma, foi realizado um ensaio para avaliar a efic?cia do produto em teste frente a Dermatobia hominis em bovinos infestados naturalmente e dois ensaios de efic?cia anti-helm?ntica em bovinos naturalmente e artificialmente infectados por nemat?ides gastrointestinais. A m?dia da efic?cia carrapaticida para bovinos artificialmente infestados por R. microplus ao longo dos 23 dias ap?s o tratamento foi de 87,40%. O resultado da efic?cia preventiva foi de 98,12%; 98,68%; 98,36%; 97,88%; 96,76%; 96,45%; 96,84%; 97,03%; 95,36%; e 87,07% respectivamente para os dias experimentais +7, +14, +21, +28, +35, +42, +49, +56, +63, +70. A efic?cia carrapaticida para bovinos naturalmente infestados por R. microplus foi de 96,30%; 96,90%; 95,98%; 96,83%; 98,32%; 96,12%; 96,15%; 98,8%; 97,18%, 99,12%; 97,18%; 98,04% e 77,50%, respectivamente para os dias experimentais +7, +14, +21, +28, +35, +42, +49, +56, +63, +70, +77, +84 e +91 para o grupo tratado. A efic?cia do produto em teste para D. hominis foi de 90,70% e 96,84%, para os dias +7 e +14. Os valores de efic?cia anti-helm?ntica em bovinos naturalmente infectados por nemat?ides gastrointestinais foi de 92,17%; 89,32%; 87,38% respectivamente para os dias experimentais +7, +14, +21 para o grupo tratado. Para bovinos artificialmente infectados por nemat?ides gastrointestinais, a efic?cia foi de 92,59%; 97,62%; 87,82%; 86,96%; 96,00% respectivamente para Haemonchus placei, Trichostrongylus axei, Cooperia punctata, Cooperia pectinata e Oesophagostomum radiatum. A associa??o de abamectina 0.6% com fluazuron 3.0% demonstrou ser eficaz em bovinos artificialmente e naturalmente infestados por R. microplus, assim como apresentou efic?cia para D. hominis. O produto em teste apresentou efic?cia tamb?m na redu??o de ovos por grama de fezes (OPG) em bovinos naturalmente infectados por nemat?ides gastrointestinais, assim como, demonstrou ser efetivo frente a infec??es artificiais por H. placei, T. axei e O. radiatum, e apresentou-se moderadamente efetivo frente a C. pectinata e C. punctata.

Artrite-encefalite dos Caprinos (CAE) é uma enfermidade infecciosa, multissistêmica, causada por um lentivírus, e infecta caprinos de todas as idades, independente do sexo, raça e tipos de produção econômica. Os principais sintomas descritos são leucoencefalomielite, artrite, pneumonia crônica intersticial e mamite intersticial endurativa. A CAE possui distribuição mundial, no Estado de São Paulo encontra-se amplamente disseminada no rebanho caprino. Com o intuito de aprofundar os conhecimentos sobre o vírus da Artrite-encefalite dos caprinos (CAEV) serão realizados estudos de sequenciamento de parte do cDNA e análise filogenética de amostras detectadas de órgãos, líquido sinovial, sêmen e leite de caprinos naturalmente infectados e soropositivos ao IDGA para o vírus da CAE e correlacionar as variantes genéticas com a sintomatologia, a forma clinica preferencial e a patogenicidade. Para o estudo filogenético serão amplificados, por RT-PCR, e sequenciados, parte do gene pol e o gene tat das amostras. Este estudo possibilitará o conhecimento das estirpes virais existentes no rebanho caprino do estado de São Paulo e a sua patogenicidade. A pesquisa de mutações encontradas por meio da análise do estudo filogenético do vírus poderá mostrar se a variante encontrada apresenta predileção por uma determinada expressão clínica. O seqüenciamento genético poderá permitir, também no futuro, uma maior eficiência na produção de antígenos virais para sorodiagnóstico e vacinas a partir das cepas circulantes encontradas. / Caprine arthritis-encephalitis (CAE) is an infectious disease, multisystem caused by a lentivirus, and infects goats of all ages, regardless of sex, race and types of economic production. The main symptoms are leukoencephalomyelitis, arthritis, chronic interstitial pneumonia and interstitial mastitis induration. CAE has a worldwide distribution in the State of São Paulo is widely disseminated in the goat herd. Aiming to deepen knowledge about the virus caprine arthritis-encephalitis (CAEV) studies will be performed sequencing of part of the cDNA and phylogenetic analysis of samples detected in organs, synovial fluid, semen and milk of goats naturally infected and seropositive AGID test for CAE virus and to correlate genetic variants with the symptoms, the clinical form of preferential and pathogenicity. For the phylogenetic study will be amplified by RT-PCR and sequenced, part of the pol gene and the gene tat of the samples. This study will allow the knowledge of existing viral strains in goat herd in the state of Sao Paulo and its pathogenicity. The analysis of mutations found by analyzing the phylogenetic analysis of the virus may show if the variant has found a predilection for a particular clinical expression. The gene sequencing will allow, in future, greater efficiency in the production of viral antigens for serodiagnosis and vaccines from the circulating strains found.

Includes bibliographical references (leaves [259]-290) Investigates nitrogen assimilation and metabolism in rumen bacteria with the object of understanding the basic process and their controls.

Includes bibliographical references (leaves 196-220) Studies the growth, body composition, feed intake of grazing animals, the use of anabolic agents, fatty acid composition of ruminants fats; and, the effect of saturated fat on human health.

Includes bibliographical references (leaves [259]-290) / xxviii, 290 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Investigates nitrogen assimilation and metabolism in rumen bacteria with the object of understanding the basic process and their controls. / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Sciences, 1991

Bibliography: leaves 102-114. This study evaluates the difference in the nutritive value of rice straw varieties using chemical composition and digestibility measurements. It assesses several methods for improving the nutritive value of rice straw and the effect of urea treatment and rice straw quality on the colonisation of ruminal fungi and the characteristics of stem tissue structure.

Data is limited evaluating infrequent supplementation of urea or biuret to ruminants consuming low-quality forage (<6% crude protein). Therefore, a series of experiments were designed to compare the effects of daily (D) and alternate day (2D) supplementation of two non-protein nitrogen (NPN) sources (urea or biuret) to ruminants consuming low-quality forage. Experiment 1 was a N balance study using five wethers in an incomplete 5 x 4 Latin square design (five treatments; four 24-d periods) with a 2 x 2 factorial arrangement of treatments (two sources of NPN and two supplementation frequencies) and an unsupplemented control. Supplements, consisting of urea or biuret mixed with ground soy hulls and dried molasses, were isonitrogenous (approximately 26% crude protein; dry matter basis) and offered D or 2D. The 2D supplemented lambs received double the quantity of supplemental N on their supplementation day compared with D lambs; therefore, all D and 2D treatments received the same amount of supplemental N over a 2-d period. Experiment 2 was a 70-d cow performance study using 80 spring-calving cows during the last third of gestation. Cows were stratified by age, body condition score, and expected calving date, and assigned randomly within stratification to one of the five treatments described in Experiment 1 above. They were then sorted by treatment and randomly assigned to 1 of 20 pens (4 cows/pen, 4 pens/treatment). Experiment 3 was a site of digestion study using five ruminally and duodenally fistulated steers to compare D and 2D supplementation of urea or biuret on forage intake, ruminal fermentation, site and extent of nutrient digestion, and rumen microbial efficiency. Five ruminally and duodenally fistulated steers were used in an incomplete 5 x 4 Latin square design with the same treatments described in Experiment 1. The results for Experiment 1 reported that DM, OM, and N intake, DM, OM, and N digestibility, N balance, and digested N retained were greater (P<0.03) for supplemented wethers compared with CON with no difference (P>0.05) because of NPN source or SF. Supplemented lambs had increased plasma urea N (PUN) compared with CON (P<0.01) and urea treatments had greater PUN compared with biuret (P<0.01). Also, PUN was increased (P=0.02) for D compared with 2D treatments. In addition, data suggest that PUN exhibited less fluctuation on the day of a supplementation event for biuret compared with urea. Experiment 2 demonstrated that pre- and post- calving (within 14 d and 24 h of calving, respectively) cow weight and body condition score changes were more positive (P<0.05) for supplemented groups compared with the CON. In Experiment 3, forage OM intake and OM digestibility were not affected (P>0.05) by NPN supplementation, NPN source, or SF. However, total OM and N intake were increased (P<0.01) with supplementation. Duodenal flow of OM tended (P=0.08) to increase with NPN supplementation while N flow was greater (P=0.04) with NPN supplementation compared with the control. In addition, duodenal bacterial N flow was increased with NPN supplementation (P=0.04) and for biuret compared with urea (P<0.01). Bacterial efficiency (g bacterial N/kg OM truly digested in the rumen) was greater for the control compared with NPN treatments (P<0.01) while biuret had greater true N disappearance compared with urea (P=0.01). Intestinal disappearance (% of duodenal flow) of OM and N was not affected by NPN supplementation, NPN source, or SF. However, apparent total tract N digestibility was increased with NPN supplementation (P<0.01) and not affected by NPN source or SF. In addition, ruminal NH���-N increased (P<0.04) on the day all supplements were provided and the day only daily supplement were provided with supplemental NPN. However, an NPN source x SF interaction (P=0.03) on the day all supplements were provided indicated NH���-N increased at a greater rate for urea as SF decreased compared with biuret. Ruminal NH���-N on the day only daily supplements were provided was greater for D compared with 2D (P=0.02). This data suggests that ruminal degradation of biuret to NH���-N was more moderate and prolonged compared with urea, possibly improving use by ruminal microflora. On the day all supplements were provided, D treatments had increased (P=0.05) ruminal indigestible acid detergent fiber passage rate and ruminal liquid volume compared with 2D treatments. Overall, NPN supplementation when feeding low-quality forage (<6% CP) was more beneficial than compared to a negative control, for increasing efficiency of forage digestion, N use, and animal performance. While at the same time indicating that the infrequent supplementation of urea or biuret was not detrimental to forage nutrient utilization, N efficiency or cow performance. This research will provide researchers and ruminant livestock producers with original information that can be used in designing winter supplementation strategies that decrease supplementation costs. Keywords: Urea, Biuret, Forage, Non-Protein Nitrogen, Supplementation, Frequency / Graduation date: 2003

The main objective of this project was to investigate the effects of the type of dried distillers grains with solubles (wheat DDGS, corn DDGS, and blend DDGS (eg. wheat:corn = 70:30)) and bio-ethanol plant origin on the nutrient variation and availability in ruminants. In addition, DDGS products were studied as opposed to their parental grains. The project was divided into the several following studies. In Study 1, we studied the nutritive value of DDGS products in terms of (1) chemical profiles, (2) protein and carbohydrate sub-fractions associated with different degradation rates, and (3) digestible component nutrients and energy values using the NRC 2001-chemical approach and the in situ assay-biological approach. Also, we tested the validity of acid detergent insoluble crude protein (ADICP) and acid detergent lignin (ADL) to predict the potential degradability of DDGS. Due to starch fermentation in the ethanol process, the chemical components in DDGS became approximately threefold more concentrated than in feedstock grains. Slowly degraded protein (PB3) and unavailable protein (PC) increased in DDGS, indicating a decrease in the overall protein degradability in the rumen. Intermediately degraded protein (PB2) was higher for corn DDGS than for wheat DDGS and blend DDGS (54.2 vs. 27.7 vs. 30.8 %CP), while PB3 was higher for wheat DDGS and blend DDGS (29.9 vs. 51.2 vs. 53.2 %CP). Mainly as a result of differing heat conditions, PC differed significantly between wheat DDGS originated at different bio-ethanol plants (0.7 vs. 7.6 %CP). The prediction of truly digestible CP (tdCP) and NDF (tdNDF) differed between the NRC 2001-chemical approach and the in situ assay-biological approach; however, both approaches reported similar energy values. These values were the highest for corn DDGS (DE3X: 3.9 Mcal kg-1), followed by blend DDGS (DE3X: 3.6 Mcal kg-1), and wheat DDGS (DE3X: 3.4 Mcal kg-1). Corn DDGS was superior to corn, wheat DDGS was similar to wheat and corn, and blend DDGS was similar to corn. No significant differences in energy values were reported between bio-ethanol plants. ADICP was not an accurate indicator of the potential degradability of protein in DDGS samples, while ADL seemed to be an acceptable indicator of the potential degradability of DM (r = -0.87; P<0.01), CP (r = -0.89; P<0.01), and NDF (r = -0.82; P<0.01) in wheat DDGS samples incubated in rumen during 48 h.<p> In Study 2, we studied the ruminal and intestinal digestion profiles and the hourly effective rumen degradation ratios between nitrogen (N) and energy. The results showed a reduction in the effective degradability of DM (EDDM), OM (EDOM) and CP (EDCP) of wheat DDGS relative to wheat; however, corn DDGS remained the same as corn. The effective degradability of NDF (EDNDF) did not vary between the DDGS samples and feedstock grains. Among DDGS types, EDDM ranged from 52.4 to 57.7 %, EDOM from 46.4 to 53.5 %DM, and EDCP from 34.0 to 45.6 %CP, being higher as the proportion of wheat in feedstock increased. No significant differences in EDDM, EDOM, EDCP and EDNDF for wheat DDGS were detected between the different bio-ethanol plants. The hourly effective degradability ratios between N and energy indicated a potential excess of N in rumen when DDGS samples were evaluated as single ingredient. This excess increased as the proportion of wheat in feedstock increased. Estimated intestinal digestibility of rumen bypass protein (IDP) was similar between wheat and wheat DDGS, but higher in corn DDGS than in corn. Blend DDGS had the highest IDP (93.9 %RUP). Due to the significantly different PC sub-fraction found in wheat DDGS originated at the different bio-ethanol plants, a large but numerical difference was detected in IDP (89.4 vs. 75.9 %RUP).<p> In Study 3, we used both the DVE/OEB System and the NRC 2001 Model to reveal the metabolic characteristics of DDGS protein and predict the protein supply to dairy cattle. The two models showed higher protein values (DVE or MP) for DDGS samples than for feedstock grains. The higher IDP for blend DDGS largely contributed to the higher protein value relative to wheat DDGS and corn DDGS (MP: 277 vs. 242 vs. 250 g kg-1 DM). Similarly, protein values differed significantly between the bio-ethanol plants mainly as a result of the numerical but large difference in IDP (MP: 272 vs. 223 g kg-1 DM). According to the two models, the degraded protein balance for DDGS products was higher than in the parental grains. Wheat DDGS showed the highest potential N excess (DBPNRC: 78 g kg-1 DM). For corn DDGS, however, the DVE/OEB System suggested a potential N excess (11 g kg-1 DM) while the NRC 2001 Model exhibited a potential N deficiency (-12 g kg-1 DM). The degraded protein balance for wheat DDGS was similar between the different bio-ethanol plants.<p> In conclusion, the chemical and biological characteristics of DDGS varied among types and between wheat DDGS samples manufactured at the different bio-ethanol plants. Thus, it is inappropriate to assume fixed values for the nutritive value of DDGS without considering factors such as type of grain used and bio-ethanol plant origin. Further research with higher number of samples will help to clarify the use of the chemical profile to predict energy values and the potential degradability of DDGS.

El objetivo principal de la presente tesis doctoral fue estudiar la posibilidad de mejorar la calidad nutritiva de la leche de oveja y de cabra, y en particular la concentración de ácido linoleico conjugado (CLA) mediante la incorporación de diferentes fuentes de lípidos vegetales a la ración.El primer capitulo fue realizado para investigar los efectos de la suplementación con Semillas Enteras de Lino (WLS) o de Aceite de Lino (LSO) sobre la producción y composición de leche, así como el perfil de ácidos grasos (AG) de leche y queso. Las concentraciones de AG de cadena media y de AG saturados fueron más bajas, y las de AG insaturados y de cadena larga más altas en la leche de los tratamientos con lino. El ácido alfa-linolénico aumentó más con la semilla que con el aceite, mientras que el CLA (ácido ruménico, RA) aumentó más con el aceite que con la semilla. En paralelo, el ácido trans-11 vaccénico (TVA) aumentó únicamente con el aceite. De manera general, la composición en AG de quesos curados (60 días de maduración) fue similar a la de la leche del correspondiente tratamiento experimental.En el segundo capítulo se utilizaron 24 ovejas de raza Lacaune para estudiar los efectos de las semillas enteras de cártamo (WSF) sobre la producción y composición de leche, así como sobre su perfil de AG, en particular CLA. En la leche producida por el grupo WSF, las concentraciones de AG de cadena larga y de AG insaturados fueron más altas, mientras que las de AG de cadena corta y de AG saturados fueron más bajas. Las concentraciones de CLA (RA) y de TVA en leche fueron mayores en el grupo WSF.En el tercer capítulo, se realizaron dos ensayos experimentales con el objetivo de estudiar los efectos de la inclusión del aceite de soja (SBO) y de un complejo de enzimas fibrolíticas (E) sobre la digestibilidad de los nutrientes de la ración y la producción y composición de leche. Cuando SBO se utilizó solo, no tuvo consecuencias sobre las digestibilidades de MS, MO y FND. El tratamiento E incrementó las digestibilidades de MS, MO y FND. Sin embargo, cuando fueron utilizados conjuntamente (SBO+E) el aceite de soja anuló las mejoras ofrecidas por E. En el experimento de ordeño, las concentraciones de ácido oleico, TVA, linoleico y CLA fueron más altas por efecto del aceite, con respuestas más evidentes en raza Lacaune que en Manchega. La adición de enzimas incrementó la producción de leche. El cuarto capítulo consistió en un experimento llevado a cabo con 24 cabras Murciano-Granadinas con el objeto de estudiar los efectos de la suplementación con SBO sobre la producción y composición de leche, y su perfil de AG, especialmente de CLA y de TVA. La concentración de AG de cadena corta y media en leche se redujo, mientras que la de AG de cadena larga aumentó. SBO redujo el ratio de AG saturados/insaturados así como el índice de aterogenicidad. Comparado con el control, las concentraciones de CLA y TVA en la leche fueron triplicadas por efecto del aceite de soja.En conclusión, los lípidos de origen vegetal incrementaron el CLA (RA) y el ácido trans-11 vaccénico, obteniéndose los incrementos más altos con la utilización de aceites vegetales, especialmente con aceite de soja en ovejas de raza Lacaune o en cabras Murciano-Granadinas. Por el contrario, las semillas enteras de lino permitieron un mayor aumento del ácido alfa-linolénico, de tipo n-3. A la dosis utilizada, el aceite de soja no afectó la digestibilidad de la fibra, pero anuló el efecto positivo de las enzimas observado sobre la digestibilidad. / The present Doctoral Thesis was carried out to study the possibility of enhance the nutritive quality of sheep and goat milk using the incorporation of different sources of vegetal fat to the diet.The first experiment was performed to investigate the effects of feeding whole linseed (WLS) or linseed oil (LSO) to dairy ewes on lactational performance, milk and cheese fatty acids profile and CLA content. Short chain fatty acids (FA) remained unchanged while medium chain and saturated FA were decreased and large chain and unsaturated FA (including mono and poly-unsaturated FA) were increased by WLS and LSO. Feeding WLS was more useful on increasing milk alpha-linolenic acid content, while feeding LSO allowed a higher increase of rumenic acid. Similarly, trans-11 C18:1 (trans vaccenic acid or TVA), precursor of CLA, was only increased by LSO. Except for short chain FA, the FA profile of 60-d-old cheeses made from milk of the ewes receiving the experimental treatments was similar to the FA profile of the milk.In the second study, a total of 24 Lacaune dairy ewes at 49±7 DIM were used to study the effects of adding whole safflower seeds (WSF) to the concentrate on dairy performance and Conjugated Linoleic Acid (CLA) in milk. Feeding WSF increased concentrations of long chain and unsaturated FA, and decreased short chain and saturated FA. Concentrations of rumenic (cis-9, trans-11 CLA) and TVA acids in milk were increased in animals fed WSF. In addition, WSF reduced the saturated/unsaturated FA ratio and the atherogenicity index of the milk fat, but increased the ratio n-6/n-3 FA. In the third chapter, two experiments were performed to study the effects of feeding soybean oil (SBO) and a fibrolytic enzyme complex (E) on nutrients digestibility (trial 1) and lactational performance of dairy ewes (trial 2). When used alone, feeding SBO increased ether extract digestibility without varying the DM, OM and NDF digestibilities, while the E treatment increased DM, OM and NDF digestibilities. In contrast, when fed together with the enzyme complex, SBO reduced digestibilities of DM, OM and NDF, being the enzyme supplement unable to reincrease nutrients digestibility. In a milking trial, milk FA variations were higher in Lacaune than in Manchega ewes. Oleic acid, TVA, linoleic acid and CLA were increased.The fourth chapter consisted in an experiment where a total of 24 Murciano-Granadina dairy goats were used to study the effects of feeding soybean oil (SBO) on lactational performance and milk fatty acids (FA), particularly CLA and TVA. Feeding SBO increased milk concentrations of linoleic, oleic and stearic FA. As a consequence, feeding SBO reduced the saturated to unsaturated FA ratio and the atherogenicity index, but increased the n-6/n-3 FA ratio. Compared with the control, milk contents of cis-9, trans-11 CLA and TVA in the SBO treatment were almost triplicated. In conclusion, vegetal fat increased CLA (rumenic acid) and TVA, being the highest increases obtained in the case of feeding vegetal oils, particularly when using soybean oil in Lacaune ewes or Murciano-Granadina goats. In contrast, whole linseed grains enhance better the alpha-linolenic acid (n-3). Under the circumstances of our experiment, soybean oil did not affect fiber digestibility except when used together with the fibrolytic enzyme complex, in which case reduced DM, OM and fiber digestibilities.

Copper is one of the most important trace elements in ruminant nutrition. Its deficiency causes certain pathologies that can be cured by supplementation, by either five ("inorganic") or complexed ("chelated") forms. With the objective of being able to quantitatively compare the distribution of copper between the two forms of supplements, the speciation of copper in ruminant fluids was studied here. For this study, copper lysine supplement was used. It was necessary to first study the acid-base and complexation chemistry of lysine with copper (II). In addition, the complexation chemistry of glycine and histidine, were investigated. Mass balance equations were used to describe the distribution of copper (II) amongst different ligands. The results of the distribution of copper (II) ions in McDougall's solution (a simulated form of bovine saliva), indicate no significant differences in the distribution of copper using the different form of supplements. 1H NMR was used to validate the results from the computer model. Using a combination of the results from the saliva simulation model and the chemical shifts from the NMR studies, the chemical shift changes that would accompany the addition of copper (II) to McDougall's solution were predicted. Results from the models do not show any appreciable differences from experimental values. Rumen samples were collected. Important peaks in the 1H NMR spectrum were assigned. The spectrum indicated that acetic acid, resulting from the fermentation in the rumen, was a good probe for monitoring the speciation pattern. Speciation calculation indicated that the bulk of the copper would be bound to ammonia in the rumen. Changes in chemical shifts that result from the introduction of copper (II) to the rumen contents were predicted. Results were compared with experimental values. Agreement between the two sets of results was found to be satisfactory. The study shows that any advantages that result from the use of copper lysine supplement are not as a result of its remaining intact. Though metal bioavailabilities are hard to predict this approach could help better our understanding of this process. The methods developed here could be extended to other metal complexation problems in biological fluids. (Abstract shortened by UMI.)