The aim of this study was to investigate the effect of presence or absence of protozoa on rumen fermentation and efficiency of microbial protein synthesis under different diets. Of 20 twin paired lambs, 1 lamb of each pair was isolated from the ewe within 24 h after birth and reared in a protozoa-free environment (n = 10), whereas their respective twin-siblings remained with the ewe (faunated, ...

T HE role of rumen protozoa in ruminant metabolism has received increasing attention during the past few years. Increased rates of gain by lambs containing protozoa compared to protozoa-free lambs were reported by Abou Akkada and el-Shazly (1964) and Yoder et al. (1964), who demonstrated that certain rations are more readily digested by faunated than by defaunated lambs. Greater rumen ammonia c...

Increasing awareness of hazards associated with the use of antibiotic and chemical feed additives has accelerated investigations into plants and their extracts as feed additives. The present review mainly discusses two classes of plant secondary compounds in this context, i.e. essential oils and saponins. The broader potential of plants and their extracts is illustrated by the progress of an EC...

A continuous culture system suitable for maintaining certain rumen protozoa was developed by modifying the procedure of Walter and Pilgrim (R.A. Weller and A.F. Pilgrim, Br. J. Nutr. 32:341-351, 1974) to include a dialyzing system. The concentration of ciliate protozoa, the pH value, and concentrations of volatile fatty acid and ammonia-N could be maintained within normal rumen limits for more ...

1. The effects of defaunation of the rumen of lambs given low-protein-high-energy diets were studied using animals fed ad lib. a basal diet of sugar and oaten chaff which was supplemented with fish meal at various levels. These diets supported relatively large populations of protozoa in the rumen. 2. A nonyl phenol ethoxylate (15 g. Teric GN9:ICI Australian Ltd) given intraruminally, was shown ...

I . The effects of defamation of the rumen of lambs given low-protein-high-energy diets were studied using animals fed ad lib. a basal diet of sugar and oaten chaff which was supplemented with fish meal at various levels. These diets supported relatively large populations of protozoa in the rumen. 2. A nonyl phenol ethoxylate (15 g, Teric GN9; ICI Australia Ltd) given intraruminally, was shown ...

The results of a 6yr research programme designed to investigate the effects of removing protozoa from the rumen of sheep and cattle are discussed in relation to recently published results of similar studies conducted in other laboratories. Evidence is presented which suggests that the removal of protozoa from the rumen is associated with an increase in the availability of protein for digestion ...

Charon ventriculi comprised over 30% of the total protozoa observed in rumen contents of a Flamenga cow fed Rhodes grass hay (Chloris gayana). Both percentage of composition and concentration decreased markedly when concentrate was added to the ration or the animal was fed in pasture. Although C. ventriculi is classified as a holotrich, concentrations of this species in the rumen appear to foll...

Three growth studies were conducted with lambs, mature wethers and young cattle to examine the effects of defaunation on production. The animals were fed a' high energy-low protein diet su.pplemented with several levels of protein. These diets supported relatively high populations of protozoa in the rumen. A single dose of nonyl phenol ethoxylate (trade name Teric GN9) was used to remove protoz...

The aim of this study was to determine if rumen protozoa could form large amounts of reserve carbohydrate compared to the amounts formed by bacteria when competing for glucose in batch cultures. We separated large protozoa and small bacteria from rumen fluid by filtration and centrifugation, recombined equal protein masses of each group into one mixture, and subsequently harvested (reseparated)...