| Registro completo |
| Provedor de dados: |
R. Bras. Zootec.
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| País: |
Brazil
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| Título: |
Digestible threonine to lysine ratio in diets for laying hens aged 24-40 weeks
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| Autores: |
Rocha,Tatiana Cristina da
Gomes,Paulo Cezar
Donzele,Juarez Lopes
Rostagno,Horacio Santiago
Mello,Heloisa Helena de Carvalho
Ribeiro,Cleverson Luís Nascimento
Troni,Allan Reis
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| Data: |
2013-12-01
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| Ano: |
2013
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| Palavras-chave: |
Amino acids
Egg production
Ideal protein
White laying hens
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| Resumo: |
Two-hundred sixteen white laying hens were used to assess the ideal ratio of digestible threonine:lysine in diets for laying hens at 24 to 40 weeks of age. Birds were assigned to a randomized block design, with six treatments, six replicates per treatment and six birds per experimental unit. The cage was used as the blocking criterion. Experimental diets contained different digestible threonine:digestible lysine ratios (65, 70, 75, 80, 85 and 90%) with 142 g/kg of crude protein. Experimental diets were formulated to be isonitrogenous and isocaloric with different contents of L-glutamic acid. Feed intake (g/hen/d), egg production (%), egg weight (g), egg mass (g/hen/d), feed conversion ratio (kg/dozen and kg/kg egg), eggshell weight (g), albumen weight (g), yolk weight (g) and body weight gain (g) were assessed. The maximum egg production was observed at 78% digestible threonine:digestible lysine ratio, while the best values of feed conversion ratio (kg/dozen egg) and feed conversion ratio (kg/kg of egg) were observed at 77.6% and 75%, respectively. Feed intake, egg mass and egg contents (yolk, albumen and eggshell) were not affected by treatments. The estimated digestible threonine:digestible lysine ratio of Hy-Line W36 laying hens at 24 to 40 weeks of age is 78%, corresponding to 5.70 g/kg of dietary digestible threonine.
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| Tipo: |
Info:eu-repo/semantics/article
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| Idioma: |
Inglês
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| Identificador: |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982013001200007
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| Editor: |
Sociedade Brasileira de Zootecnia
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| Relação: |
10.1590/S1516-35982013001200007
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| Formato: |
text/html
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| Fonte: |
Revista Brasileira de Zootecnia v.42 n.12 2013
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| Direitos: |
info:eu-repo/semantics/openAccess
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