BACKGROUND Rumen microbes play a greater role in host energy acquisition than that of gut-associated microbes in monogastric animals. Although genome-enabled advancements are providing access to the vast diversity of uncultivated microbes, our understanding of variables shaping rumen microbial communities is in its infancy. Viruses have been shown to impact microbial populations through a myria...

Rumen nitrogen metabolism values were estimated by the use of a single injection of 15(NH4)2SO4 into the rumen of sheep and consecutive 15N enrichment measurements in the rumen ammonia pool, rumen non-NH3-N (NAN) pool, rumen purine pool and blood urea-N (BUN) pool for a period of 24 h. Synthesis and degradation of N compounds in the rumen and passage of N to and from the rumen were evaluated on...

High concentrations of the ciliate Epidinium Crawley are associated with damaged regions of fresh plant material undergoing digestion in the sheep rumen. This finding supports that postulate that sequestration in the rumen explains the low rate of passage of protozoa despite the high flow rate of liquid from the rumen. The maintenance of Epidinium in the rumen, despite their slow growth rate, i...

Local feed resources, particularly low-quality roughages and agricultural crop-residues, are of prime importance for ruminants raised in the tropics. These feeds exhibit close relationships with rumen ecology, microbes and rumen fermentation patterns. A number of dietary factors could influence rumen fermentation especially the basal roughage source, its physical form and fermentation end-produ...

This study was conducted to investigate the effect of feed types on Ochratoxin A (OTA) degradation by Korean native goats. Rumen fluid from canulated goats fed whole roughage or 50% roughage served as a source of micro-organisms. Experiments were undertaken i) to investigate OTA degradation ability in a 2×4 factorial arrangement with different feed types (100% roughage vs. 50% roughage) and rum...

Bacteria attached to the rumen epithelium (or epimural community) are not well characterised and their role in rumen functioning is not totally understood. There is just one published report of a clone library from one cow that suggests that this epimural community differs from the bacteria associated with the rumen digestive contents. However, this time-consuming approach is not adapted for ex...

The activities of phosphoenolpyruvate carboxykinase, ;malic enzyme', citrate-cleavage enzyme and glucose 6-phosphate dehydrogenase were assayed in homogenates of rumen mucosa, liver and adipose tissue of cattle. Rumen mucosa cytoplasm contained activities of ;malic enzyme' approximately sevenfold those of phosphoenolpyruvate carboxykinase, suggesting that the conversion of propionate into lacta...

1. Four sheep, each fitted with a rumen fistula and a re-entrant cannula at the proximal duodenum were fed a semi-purified diet containing urea as the only nitrogen source. The quantities of total protozoal amino acid-N (TPAN) present in the rumen and entering the duodenum were determined when the mean rumen dilution rate (D) was low (0.034/h) and when D was increased to 0.078/h by the intrarum...

Monitoring rumen conditions in cows is important because a dysfunctional rumen system may cause death. Sub-acute ruminal acidosis (SARA) is a typical disease in cows, and is characterized by repeated periods of low ruminal pH. SARA is regarded as a trigger for rumen atony, rumenitis, and abomasal displacement, which may cause death. In previous studies, rumen conditions were evaluated by wirele...

Two rumen protozoa vaccine formulations containing either whole fixed Entodinium or mixed rumen protozoa cells were tested on Merino sheep with the aim of decreasing the number and/or activity of protozoa in the rumen. Negative control (no antigen) and positive control (Tetrahymena corlissi antigens) treatments were also included in the experiment. Blood and saliva were sampled to measure the s...