1. The absorption rates of calcium, inorganic phosphate (Pi) and magnesium were determined from buffered solutions placed in the temporarily isolated and washed reticulo-rumen of conscious sheep. The basic composition of these solutions was similar to that found in supernatant fractions of ultracentrifuged rumen contents. 2. The Pi concentrations studied in these solutions were 2, 8.7, 14, 17.3...

Thirty neonatal male Holstein calves fed by starter diets containing ground wheat (GW) or dry-rolled wheat (DRW) to 12 weeks of age. Skeletal growth measures, starter digestibility, starter intake, blood metabolites and rumen metabolites of nursing calves were assessed in weeks 4, 8 and 12 to assess rumen development and find the optimum method of wheat processing for calves. Calves were weaned...

Five total mixed rations prepared from finger millet (Eleusine Coracana) straw as a roughage (48%) and mixed concentrate (52%), supplemented with a 1% isoacid mixture (i-C4, i-C5, C5 and phenylacetic acid in equal proportions) or oil (groundnut oil, 5% more than the control) or urea (5% more nitrogen than the control), and protein (groundnut cake, 5% more nitrogen than the control) were given i...

Sheep were fed once daily with 300 or 600 g dried perennial ryegrass (Lolium perenne) or white clover (Trifolium repens). Total rumen contents were sampled once daily at various intervals up to 24 h after feeding for 6 d. Total weight of fresh rumen contents and dry matter (DM), organic matter and particulate matter concentrations were measured and the particle size distribution of rumen conten...

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...

In young ruminants, the reticular groove ensures that ingested milk is channelled past the forestomach to avoid malfermentation. It has been speculated that some adult wild ruminants, in particular browsing species, maintain a functional oesophageal (reticular) groove, that soluble nutrients can thus bypass the rumen, and that thus the energetic gain from the diet can be increased. We inserted ...

Rumen methanogenesis represents an energy waste for the ruminant and an important source of greenhouse gas; thus, integrated studies are needed to fully understand this process. Eight fauna-free sheep were used to investigate the effect of successive inoculation with holotrich protozoa then with total fauna on rumen methanogenesis. Holotrichs inoculation neither altered rumen fermentation rate ...

The rumen microbial ecosystem produces methane as a result of anaerobic fermentation. Methanogenesis in the rumen is thought to represent a 2-12% loss of energy intake and is estimated to be about 15% of total atmospheric methane emissions. While methanogenesis in the rumen is conducted by methanogens, PCR-based techniques have recently detected many uncultured methanogens which have a broader ...

Fractional rate of degradation (kd) of fermentable nutrients in the rumen is an important parameter in modern feed evaluation systems based on mechanistic models. Estimates of kd for starch was obtained on 19 starch sources originating from barley, wheat, oat, maize and peas and treated in different ways both chemically and physically. The starch sources were fed in mixed diets together with gr...

Lipid metabolism in the rumen is responsible for the complex fatty acid profile of rumen outflow compared with the dietary fatty acid composition, contributing to the lipid profile of ruminant products. A method for the detailed dimethylacetal and fatty acid analysis of rumen contents was developed and applied to rumen content collected from lambs fed lucerne or concentrate based diets suppleme...