Nitrogen compounds balance and microbial protein production in dairy heifers fed with coffee husk in substitution of corn silage

Revista Brasileira de Zootecnia

Oliveira, André Soares de¹  Pina, Douglas dos Santos¹  Valadares Filho, Sebastião de Campos¹  Valadares, Rilene Ferreira Diniz¹  Campos, José Maurício de Souza¹  Teixeira, Rafael Monteiro Araújo¹ 

[1] UFV, Viçosa

关键词: ammonia;    microbial efficiency;    nitrogen;    plasma urea;    purine derivatives     IntroduçãoO melhoramento de índices zootécnicos como taxa de natalidade;    idade à primeira cria e produção de leite;    indicadores de maior eficiência biológica;    deve ser objetivo em todo sistema de produção;   

DOI  :  10.1590/S1516-35982007000700030

学科分类：兽医学

来源: Universidade Federal de Vicosa

【 摘 要 】

The objective was to evaluate the effect of the substitution of corn silage by coffee husk in diets for dairy heifers on the ruminal variables, nitrogenous compounds and e microbial protein production. Twenty-four dairy Holstein heifers, purebred and crossbred, were assigned to a randomized block design, with four treatments and six blocks, according to the animal initial weight. The treatments were four coffee hulls levels: 0.0, 7.0, 14.0, and 21.0 (% DM total), in substitution of corn silage. Daily, all the heifers was fed with 2 kg of concentrate The nitrogenous (N) compounds intake and and fecal N excretion linearly ncreased with the substitution of corn silage by coffee husk that resulted in positive N balance, with average of 22.31 g/day for all the diets, however, the percentage of N absorbed in relation to the consumed reduced linearly. The ruminal ammonia concentrations and the plasma urea concentration (NUS), average of 11.93 and 10.08 mg/dL respectively, was not affected by the inclusion of coffee husk in the diet. The excreções of acid úrico, alantoína and purina derivatives, the absorbed purinas, the microbial N (N mic) and the microbial efficiency (Efic M) linearly reduced with the partial substitution of corn silage coffee husk. Observing reduction of 1,08 g/day of Nmic and 1.96 gPB/kg NDT of Efic M per unit of coffee husk added to the diet. The inclusion of coffee husk in levels of up to 21% DM in diets for dairy heifers reduces the microbial nitrogen production and the microbial efficiency, what could be harm to the animal performance.

【 授权许可】

CC BY-NC