Digestible tryptophan:lysine ratio for laying hens
Contribuinte(s) |
UNIVERSIDADE DE SÃO PAULO |
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Data(s) |
24/10/2013
24/10/2013
2012
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Resumo |
The objective of this study was to evaluate the requirement of digestible tryptophan for white laying hens in the production stage fed diets of different digestible tryptophan: digestible lysine ratios, as well as animal performance and histological alterations in their reproductive and digestive systems. A total of 280 white laying hens at 29 weeks of age were distributed in a completely randomized design with five treatments and seven replications with eight birds in each. The treatments consisted of a base feed, formulated with corn, soybean meal and corn gluten meal, and supplemented with the synthetic amino acids L-lysine, DL-methionine, L-threonine, L-isoleucine, L-arginine, and L-valine, so as to meet the nutritional requirements for laying hens, except for digestible tryptophan. The basal diet was supplemented with 0.00; 0.017; 0.035; 0.052; and 0.069 g/kg of L-tryptophan in substitution for corn starch with the objective of reaching the levels of 0.151; 0.167; 0.183; 0.199; and 0.215 g/kg of digestible tryptophan in the feed. For the ratio between digestible amino acids and lysine, the recommendation of Brazilian Tables for Poultry and Swine was followed, except for the digestible tryptophan: digestible lysine ratios, which were 19, 21, 23, 25 and 27 for each treatment. The variation in the digestible tryptophan: digestible lysine ratio promoted changes in performance and in the histological characteristics, improving the results. The digestible tryptophan: digestible lysine ratio of 24.5% in the feed of white laying hens in production stage promotes better animal performance and histological results. CNPq [141196/2009-2] CNPq |
Identificador |
REVISTA BRASILEIRA DE ZOOTECNIA-BRAZILIAN JOURNAL OF ANIMAL SCIENCE, VICOSA-MG, v. 41, n. 10, supl. 1, Part 2, pp. 2203-2210, OCT, 2012 1516-3598 http://www.producao.usp.br/handle/BDPI/35933 10.1590/S1516-35982012001000010 |
Idioma(s) |
eng |
Publicador |
REVISTA BRASILEIRA ZOOTECNIA BRAZILIAN JOURNAL ANIMAL SCI VICOSA-MG |
Relação |
REVISTA BRASILEIRA DE ZOOTECNIA-BRAZILIAN JOURNAL OF ANIMAL SCIENCE |
Direitos |
openAccess Copyright REVISTA BRASILEIRA ZOOTECNIA BRAZILIAN JOURNAL ANIMAL SCI |
Palavras-Chave | #EGG PRODUCTION #HISTOLOGICAL EFFECTS #POULTRY INDUSTRY #ISOLEUCINE #REQUIREMENT #PERFORMANCE #VALINE #AGRICULTURE, DAIRY & ANIMAL SCIENCE #VETERINARY SCIENCES |
Tipo |
article original article publishedVersion |