O presente trabalho teve como objetivo estudar os efeitos da suplementação de ácido linoléico conjugado (CLA), associada à redução do nível de proteína bruta (PB) da dieta de frangos de corte. No primeiro ensaio, o período experimental transcorreu dos 21 aos 41 dias, quando 1440 machos da linhagem Ross, com mesmo peso inicial, foram distribuídos em delineamento inteiramente casualizado, em esquema fatorial 3x3, sendo três níveis de CLA (0%, 0,5% e 1,0%) e três níveis de PB (19%, 17%, 15%). Houve redução do ganho de peso e aumento da conversão alimentar apenas em função do decréscimo de PB e ambos os fatores elevaram o índice econômico mensurado. Os rendimentos de carcaça inteira e peito diminuíram proporcionalmente a PB da dieta. Houve interação entre CLA e PB para o tamanho do fígado, ambos os fatores elevaram a gordura abdominal. Em relação aos parâmetros analisados em amostras de peito, o pH elevou-se proporcionalmente, em relação a PB, as intensidades de vermelho e amarelo foram modificadas ou pela PB, ou pelo CLA e para a luminosidade houve interação. Quanto ao perfil de ácidos graxos, a PB elevou somente o ácido esteárico e o CLA aumentou os ácidos graxos saturados e reduziu os monoinsaturados. Houve incorporação crescente dos isômeros de CLA, em função da maior inclusão do produto nas dietas com 19% ou 17% de PB. Nas dietas com 15% de PB, ocorreu um limite máximo para a incorporação do CLA. No segundo experimento, utilizando 144 aves Ross e mesmo delineamento e modelo experimental, houve efeito quadrático da PB para o balanço de nitrogênio e interação entre CLA e PB para a digestibilidade da PB dietária. / The objective of this research was to study the effects of the conjugated linoleic acid, known as CLA, associated with reduction of crude protein (CP) level in broiler diets. At first assay, the period of experiment was conducted from 21 to 41 days, when 1440 male broilers from Ross line, with the same weight initial, were allocated in accordance to a completely randomized design, with factorial model 3x3, corresponding in 3 CLA inclusions levels (0%, 0,5% and 1,0%) and 3 CPs levels (19%,17%,15%). Weight gain reduction and increased feed conversion were only related to decrease of CP inclusion and both of factors, CP and CLA inclusion levels, elevated the economic index parameters. Carcass and breast meat yields decreased due to the reduction of CP addition in diets. The interaction between CLA and CP factors modified in liver size, and both elevated the abdominal fat percents. In relation to parameters analyzed in breast samples, the pH elevated proportionally to CP inclusion, the redness and yellowness were modified by CP or CLA addition and interaction of both were detected to luminosity parameter. About fatty acid composition, the addition of CP only elevated the stearic acid and CLA inclusion improved the saturated fatty acid levels and reduced the monounsaturated fatty acid levels. An improvement on incorporation of CLA isomers was verified due to more inclusion of this product in 19% or 17% CPs diets. In the case of 15% CPs diets, the incorporation of CLA isomers had a maxim limit. In the second assay, using 144 Ross line broilers with the same design and model, a quadratic effect for nitrogen balance was verified due to CP diets and an effect of interaction between CLA and CP inclusion was found to digestibility of dietary CP.

Foi realizado um experimento com objetivo de avaliar a adição de diferentes níveis de ácido linoleico conjugado (CLA) e vitamina E na dieta de frangos de corte. Foram utilizadas 900 aves, distribuídas em delineamento inteiramente casualizado em esquema fatorial 3x3, sendo 3 níveis de CLA (0,0%, 2,0% e 4,0%) e 3 níveis de vitamina E (0 mg, 250mg e 500 mg), totalizando 9 tratamentos com 4 repetições por tratamento e 25 aves por repetição. Avaliaram-se os parâmetros de desempenho, rendimento de carcaça, densitometria e resistência óssea das tíbias, valores de TBARS, perfil lipídico e colesterol, análise sensorial e maciez objetiva da carne de peito dos animais, abatidos aos 49 dias de idade. O programa de alimentação utilizado foi dividido em 3 fases de criação: inicial (1 - 21 dias), crescimento (22 - 42 dias) e abate (43 - 49 dias), sendo as dietas formuladas a base de milho e farelo de soja. Os resultados foram analisados com o auxílio do procedimento GLM do software estatístico SAS (2003). As médias para análise sensorial e resistência óssea foram comparadas pelo teste de Tukey ao nível de 5% de probabilidade. Os demais parâmetros foram analisados com o procedimento MIXED, e obtidas as respectivas equações de regressão. Em todo o período de criação, foram encontrados efeitos significativos nas interações entre CLA e vitamina E para os parâmetros consumo de ração e ganho de peso. A conversão alimentar não foi influenciada pelas dietas.Para rendimento de carcaça, foi encontrado efeito de CLA para rendimento de asas e gordura abdominal, e interação significativa entre vitamina E e CLA para rendimento de pernas. Não foram verificados efeitos significativos para os parâmetros de resistência óssea e maciez objetiva. Para densitometria óssea, foi observada interação significativa entre os níveis de vitamina E e CLA. Em relação à análise sensorial, a adição de CLA produziu diferenças significativas para sabor, firmeza e suculência. A inclusão de vitamina E gerou efeito sobre firmeza e suculência, não alterando o sabor da carne das aves. Foi encontrado efeito de CLA sobre o perfil de ácidos graxos e colesterol. Os ácidos graxos poliinsaturados aumentaram com a inclusão de CLA à dieta. A concentração de colesterol decaiu a medida do aumento de vitamina E, o mesmo ocorrendo com os níveis de 2 e 4% de CLA. Em relação aos valores de TBARS, foram verificadas interações significativas para CLA e vitamina E, mostrando que a oxidação lipídica é altamente dependente do conteúdo de lipídios presentes da carne, como também da concentração de vitamina E. Como conclusão, a suplementação de CLA e vitamina E influenciou o ganho de peso e consumo, contudo, sem causar efeitos sobre a conversão alimentar, proporcionou aumento na densidade óssea, elevação dos parâmetros de qualidade de carne, atributos sensoriais, influenciando a oxidação lipídica e concentração de colesterol. / A study was conducted with the aim to evaluate the addiction of dietary levels of conjugated linoleic acid and vitamin E for broilers. Nine hundreds broilers chicks were allocated in factorial model 3x3, 9 treatments on total with 4 replications. Parameters of the performance, carcass yield, bone densitometry, bone resistance, TBARS values, fatty acid composition, cholesterol, sensory analysis, tenderness objective analysis of breast meat of chicks 49 days old, were evaluated. The feed program was divided in three phases: initial, grower and finisher. Diets were formulated on corn and soybean meal basis. The obtained data were analyzed by the GLM procedure of the SAS (2003) software package, means for sensory analysis and bone resistance were compared by the test of Tukey at 5% probability level. The other parameters were analyzed with the MIXED procedure and obtained the respective equations. Throughout trial period were found effects for interaction between vitamin E and CLA for feed intake and weight gain. The feed conversion ratio was not influenced for dietary treatments. Were founded CLA effect for wings yield and abdominal fat deposition, and interaction between vitamin E and CLA for legs yield. There were not effects for bone resistance and objective tenderness. For bone densitometry, were obtained interaction between CLA and vitamin E levels. With regard to sensorial analysis the CLA addiction resulted in effects for taste, firmness and juiciness, and vitamin E for firmness and juiciness, but not altering the taste of meat. CLA effect was obtained in fatty acid composition and cholesterol. The polyunsaturated fatty acids increased with the CLA levels. The cholesterol concentration reduced with the increase of the vitamin E level, the same occur with the 2% and 4% CLA levels. About TBARS values, there were interactions between CLA and vitamin E, showing that lipid peroxidation is linked to meat lipid content and vitamin E concentration. In conclusion, the CLA and vitamin E supplementation collaborated with the feed intake and weight gain, although without difference in the feed conversion ratio, increased on bone density, improvement of meat quality parameters, sensory attributes, reduction on lipid peroxidation and cholesterol.

This study was conducted to examine the antioxidative effect of conjugated linoleic acid (CLA) in irradiated, cooked ground beef patties. The hypothesis was that CLA would be retained during irradiation and would reduce lipid oxidation that is caused by irradiation. The objective was to evaluate the effects of CLA alone and in combination with irradiation on lipid oxidation, fatty acid composition, cooking loss, moisture and fat content, and trained panel sensory evaluations of beef patties. CLA was added at 0, 1, 2, or 4% level during the grinding process. Addition of CLA during the grinding process increased CLA cis-9,trans-11 and CLA trans-10,cis-12 isomers in both irradiated and non-irradiated cooked ground beef patties (irradiated at 1.6 kGy) (P = 0.0001). Weight loss during cooking was greater in irradiated beef patties than in non-irradiated patties (P = 0.004). Irradiation reduced the serumy/bloody aromatic attribute and increased browned aromatic attribute, browned aftertaste, and wet dog/hairy aromatic attribute (P < 0.05). There was no significant main effect of irradiation on the basic tastes. The linoleic acid, CLA cis-9,trans-11, and CLA trans-10,cis-12 were decreased by irradiation (P < 0.05). Although irradiation decreased the CLA isomers, higher percentages of CLA isomers were retained in irradiated patties containing a 4% free fatty acid preparation of CLA (FFA-CLA), reflecting the ability of the FFA preparation to reduce lipid oxidation that is caused by irradiation. The thiobarbituric acid reactive substances (TBARS) values were significantly higher in irradiated, cooked ground beef patties than in non-irradiated ground beef patties (P = 0.004). Although the FFA-CLA was effective in reducing lipid oxidation that is caused by irradiation, it increased painty aromatic attribute, bitter taste, and astringent aftertaste due to the soapy flavor of the free fatty acid (all P < 0.05). The FFA-CLA decreased cooked beef/brothy and serumy/bloody aromatic attribute and browned aftertaste (all P < 0.05). The 1% triacylglycerol (TAG) preparation of CLA reduced TBARS in irradiated, cooked patties to levels seen in control, non-irradiated patties. The 1% TAG concentration also provided good retention of CLA in the cooked ground beef.

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.

This study was conducted to examine the antioxidative effect of conjugated linoleic acid (CLA) in irradiated, cooked ground beef patties. The hypothesis was that CLA would be retained during irradiation and would reduce lipid oxidation that is caused by irradiation. The objective was to evaluate the effects of CLA alone and in combination with irradiation on lipid oxidation, fatty acid composition, cooking loss, moisture and fat content, and trained panel sensory evaluations of beef patties. CLA was added at 0, 1, 2, or 4% level during the grinding process. Addition of CLA during the grinding process increased CLA cis-9,trans-11 and CLA trans-10,cis-12 isomers in both irradiated and non-irradiated cooked ground beef patties (irradiated at 1.6 kGy) (P = 0.0001). Weight loss during cooking was greater in irradiated beef patties than in non-irradiated patties (P = 0.004). Irradiation reduced the serumy/bloody aromatic attribute and increased browned aromatic attribute, browned aftertaste, and wet dog/hairy aromatic attribute (P < 0.05). There was no significant main effect of irradiation on the basic tastes. The linoleic acid, CLA cis-9,trans-11, and CLA trans-10,cis-12 were decreased by irradiation (P < 0.05). Although irradiation decreased the CLA isomers, higher percentages of CLA isomers were retained in irradiated patties containing a 4% free fatty acid preparation of CLA (FFA-CLA), reflecting the ability of the FFA preparation to reduce lipid oxidation that is caused by irradiation. The thiobarbituric acid reactive substances (TBARS) values were significantly higher in irradiated, cooked ground beef patties than in non-irradiated ground beef patties (P = 0.004). Although the FFA-CLA was effective in reducing lipid oxidation that is caused by irradiation, it increased painty aromatic attribute, bitter taste, and astringent aftertaste due to the soapy flavor of the free fatty acid (all P < 0.05). The FFA-CLA decreased cooked beef/brothy and serumy/bloody aromatic attribute and browned aftertaste (all P < 0.05). The 1% triacylglycerol (TAG) preparation of CLA reduced TBARS in irradiated, cooked patties to levels seen in control, non-irradiated patties. The 1% TAG concentration also provided good retention of CLA in the cooked ground beef.

Glutamate is the primary excitatory neurotransmitter in the central nervous system. Extracellular glutamate concentrations are tightly regulated to avoid over-stimulation of glutamate receptors, which leads to a cascade of deleterious processes collectively known as excitotoxicity. Excitotoxicity is common to several neurodegenerative disorders and CNS injuries, including stroke and Alzheimer’s disease (AD). The projects described in this thesis were designed to uncover novel protective pathways in excitotoxic neurodegeneration. Excessive activation of the DNA repair enzyme, poly(ADP-ribose) polymerase-1 (PARP-1), is a convergence point for neuron death signaling in excitotoxic pathways. In AD, the peptide amyloid-β1-42 (Aβ1-42) is aberrantly produced, leading to excitotoxic neuron death in vitro. To investigate links between Aβ1-42 and PARP, we treated cultured cortical neurons with Aβ1-42 and determined whether PARP-1 contributes to neuron death. Increased neuron death was observed after Aβ1-42 exposure. A non-selective PARP-1/2 inhibitor significantly reduced Aβ1-42-induced death while elimination of PARP-1 alone was not neuroprotective. This suggests that PARP-2 or combined effects of PARP-1 and PARP-2 are required for Aβ1-42-induced neuron death. A hallmark of PARP over-activation is depletion of intracellular NAD+ and ATP levels, yet nearly all studies examining adenine nucleotide levels use separate biochemical samples to measure nucleotides individually. We developed two HPLC methods for simultaneous separation of NAD+, ATP, ADP and AMP. We determined that PARP-1 activation in astrocytes leads to near complete NAD+ depletion, followed by partial loss of ATP pools and total adenine nucleotide pools. Finally, we hypothesized that conjugated linoleic acid (CLA), a naturally occurring polyunsaturated fatty acid, is capable of enhancing neuron survival after an excitotoxic insult. Cultured cortical neurons were exposed to glutamate in the presence and absence of CLA. CLA levels likely achievable in human plasma and brain tissue during dietary supplementation regimens, protected neurons against glutamate excitotoxicity when given during or up to five hours after glutamate exposure. Several markers of mitochondrial damage and intrinsic apoptosis were examined. CLA stabilized mitochondrial membrane potential and permeability, shedding light on the mechanism of CLA neuroprotection. Overall, our research suggests a role for PARP in Aβ1-42 toxicity and identifies a novel role for CLA in neuroprotection following excitotoxicity.

Glutamate is the primary excitatory neurotransmitter in the central nervous system. Extracellular glutamate concentrations are tightly regulated to avoid over-stimulation of glutamate receptors, which leads to a cascade of deleterious processes collectively known as excitotoxicity. Excitotoxicity is common to several neurodegenerative disorders and CNS injuries, including stroke and Alzheimer’s disease (AD). The projects described in this thesis were designed to uncover novel protective pathways in excitotoxic neurodegeneration. Excessive activation of the DNA repair enzyme, poly(ADP-ribose) polymerase-1 (PARP-1), is a convergence point for neuron death signaling in excitotoxic pathways. In AD, the peptide amyloid-β1-42 (Aβ1-42) is aberrantly produced, leading to excitotoxic neuron death in vitro. To investigate links between Aβ1-42 and PARP, we treated cultured cortical neurons with Aβ1-42 and determined whether PARP-1 contributes to neuron death. Increased neuron death was observed after Aβ1-42 exposure. A non-selective PARP-1/2 inhibitor significantly reduced Aβ1-42-induced death while elimination of PARP-1 alone was not neuroprotective. This suggests that PARP-2 or combined effects of PARP-1 and PARP-2 are required for Aβ1-42-induced neuron death. A hallmark of PARP over-activation is depletion of intracellular NAD+ and ATP levels, yet nearly all studies examining adenine nucleotide levels use separate biochemical samples to measure nucleotides individually. We developed two HPLC methods for simultaneous separation of NAD+, ATP, ADP and AMP. We determined that PARP-1 activation in astrocytes leads to near complete NAD+ depletion, followed by partial loss of ATP pools and total adenine nucleotide pools. Finally, we hypothesized that conjugated linoleic acid (CLA), a naturally occurring polyunsaturated fatty acid, is capable of enhancing neuron survival after an excitotoxic insult. Cultured cortical neurons were exposed to glutamate in the presence and absence of CLA. CLA levels likely achievable in human plasma and brain tissue during dietary supplementation regimens, protected neurons against glutamate excitotoxicity when given during or up to five hours after glutamate exposure. Several markers of mitochondrial damage and intrinsic apoptosis were examined. CLA stabilized mitochondrial membrane potential and permeability, shedding light on the mechanism of CLA neuroprotection. Overall, our research suggests a role for PARP in Aβ1-42 toxicity and identifies a novel role for CLA in neuroprotection following excitotoxicity.

AN ABSTRACT OF THE THESIS OF TITLE: THE EFFECT OF SUPPLEMENTING GRAZING DAIRY CATTLE DIETS WITH FISH OIL AND LINSEED OIL ON MILK CLA AND OMEGA-3 FATTY ACID CONTENT In the recent years, there has been considerable interest in the potential health-promoting properties of both conjugated linoleic acid (cis-9, trans-11 CLA), a fatty acid produced naturally in ruminant animals, and omega-3 fatty acids. The objectives of this research were to evaluate the effects of supplementing grazing dairy cows' diet with fish oil(FO)-linseed oil(LO) blend on milk cis-9, trans-11 CLA and omega-3 fatty acids milk content. In experiment one, fourteen lactating Holstein cows were randomly assigned to one of two treatment groups (7 cows/treatment) and fed either a control or oil supplemented diet for 21 d. Treatment groups were: 1) confinement cows with free access to corn silage and hay mix plus 10 kg/d (DM basis) grain mix supplementation (CONT), or 2) grazing cows with free access to grass pasture plus 10 kg/d grain mix supplementation containing 300 g FO plus 700 g LO (FOLO). Milk samples were collected during the last 3 d of the study and analyzed for chemical and fatty acid composition. Milk production (37.05 vs. 37.29 kg/d), milk protein percentages (3.16 vs. 3.21), and milk protein yield (1.05 vs. 1.25 kg/d) were not affected (P > 0.05) by treatment diets. Milk fat percentages (3.71 and 2.28) and yield (1.25 and 0.87 kg/d) were higher (P < 0 .05) with the CONT group. The concentrations of cis-9, trans-11 CLA (0.29 vs. 2.56 g/100g fatty acid) and vaccenic acid (VA; 0.81 vs. 7.14 g/100g fatty acid) in milk fat were higher (P < 0.05) with the FOLO group. The concentrations of milk omega-3 C18:3n3, C20:5n3, and C22:6n3 were also higher (P < 0.05) with the FOLO group. In experiment two, eighteen lactating Holstein cows who were randomly assigned to one of three treatment groups for 21 d. Treatment groups were 1) indoor cows with free access to corn silage and alfalfa hay plus 10 kg/d (DM basis) grain mix supplementation (CONT), 2) indoor cows with free access to corn silage and alfalfa hay plus 10 kg/d grain mix supplementation containing 300 g FO plus 700 g LO (FOLO), and 3) grazing cows with free access to grass pasture plus 10 kg/d grain mix supplementation containing 300 g FO plus 700 g LO (FOLOP). Milk samples were taken from each cow during the last 3 d of the study. Milk production, milk protein percentages and milk protein yield were not affected (P > 0.05) by treatment diets. Milk fat percentages (3.55, 2.85, and 2.39) and yield (1.20, 0.98, and 0.84 kg/d) were lower (P < 0 .05) among the oil supplemented cows with cows on the FOLOP diet having the lowest values. Concentrations of milk cis-9 trans-11 CLA (0.33, 1.78, and 2.94 g/100g fatty acid) and VA (0.83, 5.09, and 7.15 g/100g fatty acid) were higher (P < 0 .05) among the oil supplemented cows and they were highest with cows on the FOLOP diet. Concentration of milk omega-3 fatty acids (0.5, 1.11, and 1.47 g/100g fatty acid) were higher (P < 0.05) among oil supplemented cows and was also highest for cows on the FOLOP diet. In conclusion cows fed diets containing the FO-LO blend resulted in higher milk concentrations of cis-9, trans-11 CLA and omega-3 fatty acids when compared to cows fed the CONT diet. However, greatest increases in cis-9, trans-11 CLA and omega-3 concentrations in the milk were achieved when the FO-LO blend was fed along with grazing.

The main objective of this thesis is to evaluate the trade barriers in world trade with wine. Secondary objectives will be specified during processing work.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-05-03T17:53:57Z No. of bitstreams: 1 renatadejesuscoelhocastro.pdf: 1318054 bytes, checksum: cf0df2e200943d0ff70c69c700869a16 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-13T13:51:51Z (GMT) No. of bitstreams: 1 renatadejesuscoelhocastro.pdf: 1318054 bytes, checksum: cf0df2e200943d0ff70c69c700869a16 (MD5) / Made available in DSpace on 2017-05-13T13:51:51Z (GMT). No. of bitstreams: 1 renatadejesuscoelhocastro.pdf: 1318054 bytes, checksum: cf0df2e200943d0ff70c69c700869a16 (MD5) Previous issue date: 2011-07-20 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / As forrageiras são os principais componentes da dieta de ruminantes, sendo fonte de energia e nutrientes para produção de leite e carne. Dentreos ácidos graxos encontradosnas forrageiras, dois (ácido linoleico - C18:2 n-6 e ácido α-linolênico - C18:3 n3) têm recebido atenção especial por serem precursores para a síntese do ácido linoléico conjugado (do inglês, CLA - Conjugated Linoleic Acid), uma classe compostos que reforçam a saúde encontrados predominantemente em produtos lácteos. O objetivo deste trabalho foi desenvolver um método alternativo para quantificação de C18:2 e C18:3 em forrageiras por meio da técnica de eletroforese capilar (EC), utilizando a espécie Braquiária ruzizienses como referência. Foi utilizado EC de zona com detecção indireta no UV em 224 nm, capilar com revestimento externo de teflon, e tempo de análise em torno de 10 minutos. Realizou-se um planejamento composto central rotacional (DCCR) com triplicata no ponto central para a otimização da composição do eletrólito de corrida, visando à separação do par crítico C16:0/C18:2. O eletrólito constituído de 15,0 mmol L-1 de NaH2PO4 / Na2HPO4 (pH 6,8); 8,0 de mmol L-1 Brij 35, 4,0 mmol L-1 de SDBS, 2,0% v/v de n-octanol e 43,5% v/v de acetonitrila foi otimizado. Além disso,três métodos de extraçãode lipídiosforam testados: 1- Hara e Radin; 2- Micro Folch e 3- Bligh e Dyer, os melhoresresultados foram obtidosusando o métododeHara eRadin. Após a otimização do sistema de eletrólito e escolhendo o método de extração de lipídios, duas curvas de calibração foram construídas em diferentes níveis de concentração para os ácidos graxos de interesse, utilizando C13:0 como padrão interno. Após a verificação de que não houve ocorrência de falta de ajuste nos modelos, o fator de resposta (Rf) foi calculado e aplicado para quantificação dos ácidos graxos de interesse na amostra de braquiária ruziziensis. O método otimizado por CZE foi então comparado com a cromatografia gasosa (o método AOCSoficial paraanálise de ácidosgraxo)satravés do teste t pareado.Não houve diferençaentre os métodosdentro de umintervalo de confiança de95%( p= 0,12 ).Os resultados indicam que o método otimizado por eletroforese capilar pode ser usado para determinação dos ácidos graxos mais abundantes em amostras de forragem. Este método alternativo tem vantagens sobre o método GC tradicional: menor tempo de análise, ausência de passos de derivatização no preparo da amostra, uso de colunas não-específicas e um custo analítico mais baixo. / Forages are the major components of ruminant diets, being a source of energy and nutrientsfor milk and meat production. Among the fatty acids found in forages, two (C18:2 n-6 and C18:3 n-3) have received particular attentiondue to theirroles as precursors for the synthesis of conjugated linoleic acid (CLA), a class of health enhancing compounds predominantly found in dairy products. The objective of this study was to develop an alternative method for quantification of C18:2 and C18:3 in forages through the capillary electrophoresis (CE) technique, using Brachiaria ruziziensesas the reference forage. The analytical procedure involved CE with indirect detection zone in the UV at 224 nm, capillary external coating of Teflon and analysis time around 10 minutes. Arotational central composite design (star design) with triplicate at the central point was used to optimize the composition of the electrolyte systemin order to separate the C16:0/C18:2 pair. The following electrolyte composition was obtained: 15.0 mmol L-1 NaH2PO4/Na2HPO4 buffer (pH~6,8), 8.0 mmol L-1 Brij 35, 4.0 mmol L-1 SDBS, 1.5% v/v n-octanol and 43,5% v/v ACN.Additionally, three methods of lipid extraction were tested: 1. Hara & Radin, 2. Micro Folch and 3. Bligh &Dyer; the best results were achieved by using the method of Hara and Radin.After optimizing the electrolyte systemand choosing thelipid extraction method, two calibration curves were made usingdifferentconcentrations of selected fatty acids and C13:0 as the internal standard. After checking for no occurrence of lack of fit of the models, a response factor (RF) was calculated and applied in the quantification ofselected fatty acids in the forage sample. The optimized CZE method was then compared to gas chromatography (the AOCS official method for fatty acid analysis) through the paired t-test. There was no difference between methods withina 95% confidence interval ( p= 0,12 ).Our results indicate that the optimized CE method proposed herein can be used to quantify the most abundant fatty acids in forage samples. Thisalternative methodhassomeadvantages over the traditional GC method: less timeconsuming, no derivatizationstepor specific separation columns required, and lower analytical cost.