The use of phytogenic dietary additives is being evaluated as a means to improve animal productivity. The effect of tannins seems to be the influence not only directly on the digestive process through binding of dietary proteins but also indirectly over their effects on gastrointestinal microbiota. High-throughput sequencing of 16S rRNA gene was used to analyze the impact of dietary supplementa...

The rumen microbiota enable ruminants to degrade complex ligno-cellulosic compounds to produce high quality protein for human consumption. However, enteric fermentation by domestic ruminants generates negative by-products: greenhouse gases (methane) and environmental nitrogen pollution. The current lack of cultured isolates representative of the totality of rumen microbial species creates an in...

I. A study was made of the changes in electrolyte concentrations and ruminal function which resulted from the provision of 1.3 7; sodium chloride solutions instead of fresh water to sheep consuming roughage rations in chaffed and in ground pelleted forms. 2. Significantly higher osmotic pressures were observed in the rumen fluid of the sheep drinking saline water, the change being especially ma...

The ability of ruminants to convert plant biomass unsuitable for human consumption into meat and milk is of great societal and agricultural importance. However, the efficiency of this process is largely dependent on the digestibility of plant cell walls. Supplementing ruminant diets with exogenous enzymes has the potential to improve plant cell wall digestibility and thus the efficiency of feed...

Microorganisms in the digestive tract of ruminants differ in their functionality and ability to use feed constituents. While cecal microbiota play an important role in post-rumen fermentation of residual substrates undigested in the rumen, limited knowledge exists regarding its structure and function. In this trial we investigated the effect of dietary supplementation with linseed oil and nitra...

I . The deamination, ureolytic and proteolytic activities and rates of cellulolysis and gas production in large intestinal contents have been compared with those activities and rates in rumen contents of sheep. 2. Large intestinal contents produced ammonia. The rate of ammonia production was greater in caecal contents than in faeces. Incubation of caecal contents under toluene resulted in decre...

Members of the domain Archaea contribute about 0.3 to 3.3% of the microbial small subunit (16S and 18S) rRNA in the rumen (22, 39, 60). Archaea have a range of different metabolisms and are found in many habitats (6), but those known to exist in the rumen are strictly anaerobic methanogens. Yanagita et al. (59) observed that 2.8 to 4.0% of ruminal microorganisms displayed autofluorescence chara...

Current systems for the evaluation of protein-feeds for ruminants take account of two principal nitrogen (N) requirements. One is to satisfy the needs of the rumen micro-organisms in order to maximize. microbial protein yield this N can largely be provided in any form that will give rise to enough ammonia in rumen fluid. The other N requirement is for a dietary source of true protein that wi,ll...

Ruminant production is under increased public scrutiny in terms of the importance of cattle and other ruminants as major producers of the greenhouse gas methane. Methanogenesis is performed by methanogenic archaea, a specialised group of microbes present in several anaerobic environments including the rumen. In the rumen, methanogens utilise predominantly H2 and CO2 as substrates to produce met...

The targeting of mcrA or 16S rRNA genes by quantitative PCR (qPCR) has become the dominant method for quantifying methanogens in rumen. There are considerable discrepancies between estimates based on different primer sets, and the literature is equivocal about the relationship with methane production. There are a number of problems with qPCR, including low primer specificity, multiple copies of...