Acidity effect (pH) in regulating ammonia production and microbial growth

Revista Brasileira de Zootecnia

Cunha, Luciane Tavares da¹  Borges, Arnaldo Chaer¹  Lana, Rogério de Paula¹ 

[1] UFV, Viçosa

关键词: ammonia;    deamination;    fermentation;    pH;    protein;    rumen     IntroduçãoA fermentação da proteína no rúmen pode;    muitas vezes;    produzir mais amônia que os microrganismos podem utilizar;    ocasionando mais de 25% de perda da proteína;    na forma de nitrogênio amoniacal (RUSSELL et al;   

DOI  :  10.1590/S1516-35982000000600037

学科分类：兽医学

来源: Universidade Federal de Vicosa

【 摘 要 】

- This research had as objective the evaluation of the acidity effect (pH) by adding increasing levels of corn starch on the degradation of hydrolyzed casein (Tripticase). The rumen fluid was taken from a fistulated steer in a 40% concentrate diet, and centrifuged at 500xg in 15 minutes to remove feed particles and protozoa. The incubations were done in an anaerobic environment at 39ºC in Vacuntainer® tubes. It was used 150 mg of tripticase and 0, 25, 50, 75, 100, 200 and 300 mg of corn starch in 10 mL rumen fluid. Samples were collected over the incubations and the pH, ammonia and microbial protein measured. The starch had small effect on microbial growth, but levels of 50 mg/10 mL and on completely inhibited the ammonia production. The inhibition was probably due to pH effect, since it showed higher correlation with ammonia production than the starch (0.95 vs. -0.59). Once the largest amount of tripticase was used for ammonia production, and that it was highly inhibited by acidity, mild decrease in ruminal pH by the use of concentrate can be useful to reduce losses of dietary protein by ruminal fermentation. In fact, higher amount of degradable protein could be added to the diet, helpfully the benefit of the synchronism of the starch and protein sources, as for their degradations, in the formulation of diets for ruminant animal.

【 授权许可】

CC BY-NC