Dietary Effects upon Concentrations of Protozoa in the Rumen

Abstract

Results of four experiments investigating dietary effects upon protozoal concentrations within the rumen of sheep are reported. Unextracted linseed added to a basal ration caused a significant decrease in both rumen ammonia levels and protozoal concentration. Daily infusion of 60 gm. of linseed oil into the rumen resulted in a depression of both rumen ammonia levels and protozoal concentrations. A urea supplement supplying 8 gm. of nitrogen fed A with the basal ration resulted in a significantly greater protozoal concentration than when one-half or three-quarters of the supplement was infused into the rumen 10 hr. after feeding or when the urea supplement was infused continuously. When urea and gluten were added isonitrogenously to a basal ration, protozoal concentrations with the urea supplementation were significantly greater than with gluten supplementation, which in turn were significantly greater (except at the peak of the fermentation with the unsupplemented basal ration. Greater protozoal concentrations were associated in each case with high levels of ammonia in the rumen. Copyright © 1966. American Society of Animal Science . Copyright 1966 by American Society of Animal Science