Effect of experimental period on the ruminal fermentation and microbial efficiency synthesis in cattle fed two levels of forage

Revista Brasileira de Zootecnia

Fregadolli, Fábio Luís¹  Branco, Antonio Ferriani¹  Guimarães, Kátia Cylene¹  Zeoula, Lúcia Maria¹  Caldas Neto, Saul Ferreira¹  Alcalde, Claudete Regina¹ 

[1] Universidade Estadual de Maringá, Maringá

关键词: ammonia;    experimental period;    forage level;    nitrogen;    pH   IntroduçãoA modificação dos níveis de volumosos na dieta de ruminantes é uma alternativa que vem sendo utilizada;    com o objetivo de atingir o máximo consumo de energia e melhor aproveitamento dos alimentos fornecidos em dietas balanceadas;   

DOI  :  10.1590/S1516-35982001000300037

学科分类：兽医学

来源: Universidade Federal de Vicosa

【 摘 要 】

- The objectives of this research were to evaluate the effects of two forage levels and two experimental periods on the microbial efficiency, ruminal ammonia concentration, the ruminal pH, duodenal nitrogen (N) flux and digestibility. Four Holstein steers, two years old and 340 kg of body weight, ruminally and duodenally cannulated, were used. The experimental design was a 4 x 4 latin square and animals received four treatments as folowing: two levels of forage (70 and 30%) and two experimental periods (14 and 21 days). There were effects of the forage level on the ruminal ammonia concentrations and pH. There was effect of experimental period on the intake of N. The apparent microbial efficiency synthesis ranged from 29.3 to 32.0 g microbial N/ kg OMDR. The minimum pH for high forage diet (70%) was 6.5 and for low forage diet (30%) was 6.2. The maximum ruminal ammonia concentration of 16.9 mg/100 mL was obtained for the level of 70% of forage and 18.9 mg/100 mL of ruminal fluid to the level of 30% of forage.

【 授权许可】

CC BY-NC