bacteria make up about half of the living organisms inside of the rumen. however, they do more than half of the work in the rumen. the bacteria work together. some breakdown certain carbohydrates and proteins which are then used by others. some require certain growth factors, such as b-vitamins, which are made by others. some bacteria help to clean up the rumen of others’ end products, such as ...

The aim of this study was to investigate the variations of vitamin B12 and homocysteine in blood of dairy cows during subacute ruminal acidosis (SARA). On 228 subjects ruminal liquid was collected through rumenocentesis technique and rumen pH was immediately measured by a portable pH-meter. On the basis of pH values all cows were classified (bovine class) in Group A (animals with rumen pH>5.7),...

Seventeen 350 lb (159 kg) Holstein steers were utilized to determine stability of rumen pH postmortem. Cattle were randomly assigned to two whole-corn ration treatment groups: 1) limit-fed (7.5 lb; 3.4 kg) or 2) fed ad libitum (9.5 lb; 4.3 kg). Calves were humanely euthanized, rumen fluid was collected, and pH measurements were taken at 0, 1, 2, 3, 6, 12, and 24 hours postmortem. A subset of fi...

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...

The effect of pH on rumen fermentation and microbial population was studied in a continuously cultured rumen ecosystem. A marked decrease in the production of volatile fatty acids and methane from alfalfa hay occurred when the cultures were maintained at pH values below 6.0. The decrease in acetate and methane production was greater than that of propionate production. The culture maintained at ...

Currently, the mechanism(s) responsible for the regulation of urea transporter B (UT-B) expression levels in the epithelium of the rumen remain unclear. We hypothesized that rumen fermentation products affect ruminal UT-B expression. Therefore, the effects of short-chain fatty acids (SCFA), pH, ammonia, and urea on mRNA and protein levels of UT-B were assayed in primary rumen epithelial cell cu...

Absorption of the lower fatty acids occurs directly from the rumen of sheep, in which organ they are produced as a result of bacterial fermentation. Previous work on this subject, in which the pH of the rumen was not controlled (Barcroft, McAnally & Phillipson, 1944), showed that: (a) The quantity of acid absorbed is substantial. (b) The rate of absorption from the normally filled rumen bears n...

1. Three experiments were conducted to determine the flow of nitrogen through the rumen and abomasum when cows, steers and lambs were totally nourished on volatile fatty acids infused into the rumen. 2. In two dairy cows (650-700 kg) and two large steers (370-405 kg) the daily flow of non-ammonia-N (NAN) from the rumen was 50.7 and 58 mg/kg live weight (W)0.75 respectively. 3. The flows of NAN ...

Subacute Ruminal Acidosis (SARA) corresponds to an imbalance between lactate-producing bacteria and lactate-using bacteria, which results in a change in ruminal pH associated with a prevalent consumption of rapidly fermentable carbohydrates. In our study, 216 primiparus and multiparus dairy cows were selected from 20 Italian intensive dairy herds and were divided into three groups based on the ...

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...