Digestible lysine levels in semi-heavy laying hens in the period from 28 to 44 weeks of age/Niveis de lisina digestivel para poedeiras semipesadas no periodo de 28 a 44 semanas

• Published in: Acta scientiarum. Animal sciences 2014-04, Vol.36 (2), p.145
• Main Authors: dos Santos, Tiago Antonio, Geraldo, Adriano, Machado, Luiz Carlos, Goncalves, Rogerio Amaro, Pelicia, Kleber, Simao, Sergio Domingos
• Format: Article
• Language: Spanish
• Subjects: Lysine; Nutritional requirements
• ISSN: 1806-2636
• DOI: 10.4025/actascianimsci.v36i2.21822

This study aimed to evaluate the performance of laying hens subjected to heavy semi-low crude protein (14.0%) and lysine levels while maintaining the same relation of digestible amino acid/ digestible lysine. A commercial line of 420 Isa Brown laying hens, in the period from 28 to 44 weeks of age, were distributed in 42 experimental plots. A completely randomized design with six treatments and seven replicates in four periods of 28 days/each was used. The treatments were: Control--Formulated according to the nutritional requirements proposed in the strain, containing 16.92% crude protein, 0.750% digestible lysine. Treatments 1 to 5, with crude protein levels of 14% and 0.600% of digestible lysine, 0.675%, 0.750%, 0.825% and 0.900%, respectively. The requirement of lysine, in relation to other digestible amino acids, can be estimated at 0.750% in diet with 14% crude protein, which corresponds to the average daily intake of 876 mg lysine dig. [hen.sup.-1] [day.sup.-1], without compromising the performance of hens. Keywords: ideal protein, digestible amino acid, Isa Brown. O objetivo da pesquisa foi avaliar o desempenho de poedeiras semipesadas submetidas a dietas com baixo teor proteina bruta (14,0%) e diferentes niveis de lisina, mantendo a mesma relacao aminoacidos digestiveis/ lisina digestivel. Foram utilizadas 420 poedeiras da linhagem comercial Isa Brown de 28 a 44 semanas de idade, distribuidas em 42 parcelas experimentais. Foi utilizado um delineamento inteiramente casualizado com seis tratamentos e sete repeticoes, em quatro periodos de 28 dias/cada. Os tratamentos foram: Controle--racao formulada de acordo com as exigencias nutricionais propostas no manual da linhagem, contendo 16,92% proteina bruta e 0,750% lisina digestivel. Os tratamentos testes do 1 ao 5, tiveram a reducao proteica, 14% de proteina bruta e diferentes niveis de lisina digestivel de 0,600%; 0,675%; 0,750%; 0,825% e 0,900%, respectivamente. A exigencia de lisina digestivel, em relacao aos demais aminoacidos digestiveis, pode ser estimada em 0,750% em dieta com 14% de proteina bruta, o que corresponde ao consumo medio diario de 876 mg lisina digestivel, sem comprometer o desempenho das aves. Palavras-chave: proteina ideal, aminoacidos digestiveis, Isa Brown.