Níveis protéicos e suplementação aminoacídica na dieta de frangos de corte na fase de crescimento

• Ano de defesa: 2005
• Autor(a) principal: Dionizio, Marli Arena
• Orientador(a): Rostagno, Horácio Santiago
• Banca de defesa: Moraes, George Henrique Kling de , Pupa, Júlio Maria Ribeiro
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Zootecnia
• Departamento: Genética e Melhoramento de Animais Domésticos; Nutrição e Alimentação Animal; Pastagens e Forragicul
• País: BR
• Palavras-chave em Português: Proteína ideal; Aminoácidos sintéticos; Frangos de corte
• Palavras-chave em Inglês: Ideal protein; Synthetic amino acids; Broiler chickens
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::NUTRICAO E ALIMENTACAO ANIMAL::AVALIACAO DE ALIMENTOS PARA ANIMAIS
• Link de acesso: http://locus.ufv.br/handle/123456789/1827

Six experiments were conduted to evaluate the effect of the aminoacid suplementation in diets of broiler chickens with low protein, in way to look for reduction of the pollutant effects, as well as to maximize animal performance. In the first experiment, the effect of different protein levels was evaluated and threonine:lysine ratio on the performance and the carcass parameters of broiler chickens, in the growing phase. It was used three levels of crude protein (PB) in the diet (20, 19 and 18%) and theree threonine:lysine ratio (60, 65 and 70%). There was interaction between the protein level of the diet and the threonine:lysine ratio for weight gain and feed conversion (P <0,05). The birds that received diet with 18% of protein and threonine:lysine ratio of 70% presented 3% more the of weight than the others. The birds that received diet with 18% of protein and threonine:lysine ratio of 70% presented better feed conversion. The feed consumption was not affected by the protein levels or for the threonine:lysine ratio (P>0,05). The carcass revenue, breast with bone, breast filet and leg, they were not affected for the levels of protein of the diet or for the threonine:lysine ratio (P>0,05). The percentage of abdominal fat was influenced by the threonine:lysine ratio (P <0,05). In the second experiment, the effect of the use of diets was evaluated with different protein levels and digestible lysine on the performance and carcass parameters of broiler chickens. It was used three levels of crude protein (22, 20,5 and 19%) and three levels of digestible lysine (0,97; 1,045 and 1,123%). There was not effect of the protein levels or lysine level on the weight gain and the feed conversion (P>0,05). The feed consumption was affected by the lysine level of the diet (P <0,05) and the birds that received 0,97% of lysine presented larger consumption. It was verified that there was not effect of the protein levels and of lysine on the absolute weight and the carcass revenue (P>0,05). Para the weight and the breast revenue with bone, is verified that there was effect of the lysine levels and of protein of the diet, being the birds that received smaller level of rude protein presented larger absolute weight of breast. There were not effect of the protein levels and lysine studied on the results of absolute weight and leg revenue and breast filet. With relationship to the abdominal fat, it was verified that the same suffered influence of the protein levels studied (P <0,05). The birds that received diet containing smaller protein level presented larger absolute weight and revenue of abdominal fat. There was not effect of the lysine supplementation on the results of abdominal fat (P>0,05). In the third and fourth experiments, it was evaluated the effect of different protein levels and threonine supplementation and glicina on the performance, carcass revenue and excretion of nitrogen in chickens of cut males in the growing phase. It was used two levels of crude protein (PB) in the diet (20 and 18%), two threonine:lysine ratio (60 and 70%) and supplementation or not of glicina. Significant effect of the protein level was observed on the weight gain of the birds (P <0,05), and the level of 18% of PB was what presented the largest weight gain for the period. The feed consumption and the feed conversion were not affected for the protein levels, for threonine:lysine ratio or for the clycine supplementation (P>0,05). The feed conversion of the birds that received 18% of PB was better than the one of the birds that received 20% of PB. The weight and carcass revenue were affected for the threonine:lysine ratio of the diets (P <0,05), but they didn't suffer effect of the protein levels or of the glycine supplementation. The weight and breast revenue with bone were not affected for the levels of protein of the diet, for threonine:lysine ratio or of the glycine supplementation of the diet (P>0,05). The absolute weight of the carcass and the carcass revenue were influenced by the threonine:lysine ratio of the diet, and the birds that received diet with 60% of relationship presented the best values. In the fifth and sixth experiments, the effect of diets was evaluated with low protein and supplementation with threonine and glycine, in clean and dirty enviroments, on the performance and the carcass revenue, of broiler chickens in the growing phase. It was used two threonine:lysine ratio (60 and 70%), with supplementation or not of glicina (0 and 0,3%) in two environment dirty and clean. For the weight gain, significant effect of the glycine supplementation was observed and of the environment and the birds that received diets with supplemental glycine presented larger gain (P <0,01). The birds created in dirty environment, with sanitary challenge they presented superior performance the that obtained by birds created in clean environment (P <0,01). In that phase, the feed conversion was influenced by the threonine:lysine ratio and for the supplemental glycine of the diet. The birds that received the diet containing threonine:lysine ratio of 60% and glycine supplementation presented better feed conversion when compared to the others. For feed consumption, effect of the environment was observed, where the birds in environment with sanitary challenge they presented larger consumption. Interaction was not observed among the threonine:lysine ratio, the environments and glycine supplementation.