Efficiency of microbial synthesis, pH and ammonia ruminal concentrations in F1 Limousin x Nellore bulls fed diets with five levels of concentrate

Revista Brasileira de Zootecnia

Coelho da Silva, José Fernando³  Cecon, Paulo Roberto⁴  Valadares Filho, Sebastião de Campos⁴  Valadares, Rilene Ferreira Diniz⁴  Paulino, Mário Fonseca⁴  Dias, Helder Luis Chaves²  Rennó, Luciana Navajas⁴  Costa, Marcos A. Lana¹ 

[1] Universidade Estadual do Maranhão;Universidade Estadual Norte Fluminense;Universidade Federal de Viçosa

关键词: ruminal ammonia;    concentrate;    microbial efficiency;    ruminal pH;    passage rate     IntroduçãoAs exigências protéicas dos ruminantes são atendidas mediante a absorção intestinal de aminoácidos provenientes da proteína microbiana sintetizada no rúmen e da proteína dietética não-degradada no rúmen (VALADARES FILHO;    1995);   

DOI  :  10.1590/S1516-35982000000200032

学科分类：兽医学

来源: Universidade Federal de Vicosa

【 摘 要 】

- A trial was conducted to evaluate the effects of five concentrate levels in the diet on the efficiency of microbial synthesis, balance of nitrogen compounds, ammonia concentrate and pH ruminal fluid. Five rumen, abomasum and ileum fistulated F1 Limousin x Nellore bulls were full fed diets containing 25.0, 37.5, 50.0, 62.5, and 75.0% of concentrate and allotted to a 5 x 5 latin square design. The ammonia concentrations and ruminal pH were determined in ruminal fluid samples collected right after the diets supply and 2, 4, 6, and 8 hours after. The unicompartimental model using chromic oxide as marker determined the passage rate. The efficiency of microbial synthesis, expressed by different forms, was not influenced by the use of concentrate, obtaining average values of 35.17 g Nmic/kg MODR, 33.01 g Nmic/kg CHODR, and 355.66 g MSmic/kg CHODR. The maximum ammonia concentrations, for all treatments, were 2.92 hours after the diet supply. The ruminal pH fluid linearly decreased with the concentrate levels and the collection times. The passage rates of .065, .081, .064, .049, and .046.h-1 were verified for the treatments with 25.0, 37.5, 50.0, 62.5, and 75.0% of concentrate, respectively. The addition of concentrate in the diets reduced the pH and did not alter the microbial efficiency.

【 授权许可】

CC BY-NC