Nitrogen balance, amino acid degradability and volatile fatty acid concentration in the rumen of sheep fed Stylosanthes guianensis hay

Revista Brasileira de Zootecnia

Gonçalves, Lúcio Carlos³  Miranda, Lídia Ferreira¹  Borges, Iran³  Saliba, Eloísa de Oliveira Simões³  Ladeira, Márcio Machado²  Rodriguez, Norberto Mario³ 

[1] FEAD, Belo Horizonte;Ministério da Agricultura, Pecuária e Abastecimento;UFMG, Belo Horizonte

关键词: amino acid;    degradability;    hay;    legume forages;    sheep     IntroduçãoNas últimas décadas;    considerável atenção foi dada à determinação de requisitos de proteínas para ruminantes;    tendo sido proposta uma série de sistemas ou modelos com base principalmente nas parcelas protéicas degradáveis e não-degradáveis dos alimentos;    deixando as portas abertas para a predição de exigências em aminoácidos (Rodriguez;    1996);   

DOI  :  10.1590/S1516-35982002000900026

学科分类：兽医学

来源: Universidade Federal de Vicosa

【 摘 要 】

Seven sheep fed S. guianensis hay were used to evaluate ruminal amino acid degradability, nitrogen balance and rumen volatile fatty acid (VFA) concentrations. Nylon bags technique was used for determination of the in situ degradabilities of amino acids. Bags were collected at 6, 24 and 48 hours after insertion. Duodenum and feces samples were used to determine amoniacal-N and non-amoniacal-N. To determine ruminal VFA concentrations, samples of 80 mL were collected immediately before feeding and 2, 4, 6 and 8 hours after. Nitrogen balance was 6.0 g/day. S. guianensis had 10.4 and 6.3 g of methionine and lysine, respectively, per 100 g of total amino acids. Non essential amino acids had degradation rates twice than essentials. Aminoacitic profile of undegradable protein was different than the original feed protein. The acetate:propionate ratio was 4.31. High concentrations of methionine and its low degradability make the S. guianensis an important feed when this amino acid is limiting.

【 授权许可】

CC BY-NC