A quantitative method of analysis for 2-aminoethylphosphonic acid (AEP) was developed using reverse-phase HPLC. The detection limit for AEP was 15 nM, and the detector response (peak area) was linear from AEP levels up to 100 microM (R = .99). Mean recovery of AEP added to strained ruminal fluid from faunated sheep was 98.2%. When AEP was added to a fermentation mixture at a concentration of 22...

Five in situ trials with whole-plant corn silage (WPCS) were conducted in two ruminallycannulated Holstein cows to determine 24-h ruminal disappearance of dry matter (DM), starch, and neutral detergent ®ber (NDF). In Trial 1, the effect of maturity of WPCS on ruminal nutrient disappearance was evaluated. Treatments were early dent (ED), 1/4 milk-line (1/4 ML), 2/3 milkline (2/3 ML), and black-l...

We investigated the relationship between ruminal pH and bacteria in calves fed calf starter with and without forage during weaning transition. First, 16 Holstein bull calves were obtained from dairy farms and equipped with rumen cannulas by cannulation surgery. Then, calves (73.5 ± 4.2 kg; mean ± SE) were assigned to groups fed calf starter either with forage (HAY, n = 8) or without forage (CON...

The purpose of this study was to examine the stability and host specificity of a cow's ruminal bacterial community following massive challenge with ruminal microflora from another cow. In each of 2 experiments, 1 pair of cows was selected on the basis of differences in ruminal bacterial community composition (BCC), determined by automated ribosomal intergenic spacer analysis (ARISA), a culture-...

six rumen fistulated adult sheep were used to assess the effect of tannins (hydrolysable tannin; hts) in oak leaves (quercus libani oliv.) on ruminal fermentation parameters in a change-over design experiment for 28 days in 3 periods. polyethylene glycol (peg) was used to deactivate the tannins. the three dietary treatments were control (alfalfa hay, barley grain, wheat bran, wheat straw); ol (...

Eight Holstein steers (439 kg) with "T" cannulas in the rumen and proximal duodenum were used to evaluate the characteristics of digestion of Pima cottonseed. Treatments consisted of a basal growing-finishing diet containing (DM basis) 1) 15% tapioca, 2) 15% whole linted cottonseed (Delta Pine 61, DP); 3) 15% whole lint-free cottonseed (Pima, PW), and 4) 15% ground Pima cottonseed (PG). Substit...

An experiment was conducted to investigate the effects of changes in ruminal conditions arising from feeding and sucrose supplementation to the diet on the natural abundance of 15N (delta 15N value) of some biological components and of feces and urine in sheep. Four wethers fitted with ruminal fistulas were fed on alfalfa hay cubes with or without sucrose either 2 or 12 times daily. With twice-...