Níveis de metionina+cistina digestíveis em rações para poedeiras leves, no período de 24 a 40 e de 42 a 58 semanas de idade

• Autor(a) principal: Brumano, Gladstone
• Data de Publicação: 2008
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1699
• topic: Aminoácidos; Exigências; Poedeiras; Amino acids; Nutritional requirements; Laying hens; CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::NUTRICAO E ALIMENTACAO ANIMAL

With the objective of determining of digestible sulfurous amino acids level to establish the ideal relationships methionine+ cystine/lysine in meals of light-weight laying hens in the period from 24 to 40 (first experiment) and 42 to 58 (second experiment) weeks of age, were conduced in the Section of Aviculture of the Zootechny Department of the Federal University of Viçosa. In both experiments, 216 birds of the commercial mark Hy- Line W36 were used, distributed in a blocks randomized design with 6 treatments, 6 repetitions and 6 birds for experimental unit. The digestible lysine level used in the experimental diet was from 0.770% to a daily consumption of the 731 mg/hen/day of lysine and 95 g/hen/day of meal. The digestible sulfurs amino acids levels were obtained starting from a deficient basal diet in digestible methionine+cystine (0.65%), supplemented with 0.00; 0.05; 0.10; 0.15; 0.20 and 0.25% of DL-methionine (99.2%), in way to provide a relationship methionine+cystine/lysine of 84, 91, 97, 104, 110 and 117. The experimental period had duration of 16 weeks and it was subdivided in 4 by-periods of collection of the eggs, being each one corresponding to 28 days. The parameters evaluated were the productive performance (production, weight and egg mass), of the intake consumption (meal, methionine+cystine and lysine), of the feed conversion (egg dozen and mass), egg components (albumen, yolk and shell), of the egg quality (albumen and yolk index, and Haugh units), of the non-marketable eggs, of the body weight and lysine utilization efficiency for egg production. This last parameter was used in the two experiments to correct the variation of intake consumption meal and lysine among the treatments. In the first experiment, significant effect was verified (P <0.01) of the levels of digestible methionine+cistine on the egg production and lysine utilization efficiency for egg production, reaching a plateau in 0.811 and 0.772% of digestible methionine+cistine, respectively. In the second experiment, there was quadratic effect (P <0.05) of the digestible methionine+cistine levels on the egg production and lysine utilization efficiency for egg production, at the level of 0.826 and 0.775% of digestible methionine+cistine level, respectively. The digestible methionine+cystine level considered as demand for light- weight laying hens in the period from 24 to 40 and 42 to 58 weeks of age were of 0.772 and 0.775%, corresponding to digestible methionine+cystine consumption of 682 and 708 mg/hen/day, and relationship methionine+cystine/lysine of 100 and 101%, respectively.