Rumen bacteria capable of growth on and amino acids as sole source of energy: numbers and their role in ammonia production

摘要

Excessive ammonia production by rumen micro-organisms is a major cause of inefficient N retention by ruminants. The microorganisms which break down peptides and amino acids to ammonia were identified originally as typical major species of the rumen ecosystem (Biaden et al, 1961, Appi Microbiol, 9, 175-180), but more recently a smaller, more active population that used Trypticase (pancreatic casein hydrolysate containing peptides and some free amino acids) as their sole source of energy was identified (Chen and Russell, 1989, Appi Environ Microbioi, 55, 1052-1057). The aims of the present experiments were to enumerate the latter group of bacteria in the sheep rumen and to assess their role in ammonia production.