The essential role of ruminal microflora in ruminant nutrition provides the potential for improvement in animal production via altering the numbers or activities of specific classes of microorganisms. Successful alterations will be facilitated by an understanding of the microbial ecology of the rumen based on its mechanistic underpinnings. Demonstrated improvements in ruminal fermentation can b...

The ability of ruminal microorganisms to degrade octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (high melting explosive, HMX) as consortia from whole rumen fluid (WRF), and individually as 23 commercially available ruminal strains, was compared under anaerobic conditions. Compound degradation was monitored by high-performance liquid chromatography, followed by liquid chromatography-tandem mas...

In experiment 1, 24 midlactation, multiparous Holstein cows were used in six 4 x 4 Latin squares to evaluate extruded-expelled cottonseed (EEC) as a source of ruminally undegradable protein (RUP). Diets were formulated to contain: 16% crude protein (CP), 35% RUP (SBM16); 18% CP, 35% RUP (SBM18); 16% CP, 40% RUP using EEC (EC16); and 16% CP, 40% RUP using a fishmeal-blood meal blend (FBM16). Mil...

Experiments were conducted to evaluate the availability to ruminants of lysine from hydroxymethyl lysine, a product potentially resistant to ruminal degradation yet able to release free lysine when subjected to the acidic environment of the abomasum. An in vitro ruminal fermentation assay that led to ammonia production from free lysine was used for initial assessments, but the hydroxymethyl lys...

Evaluation of the radio-transmission pH-measurement system for monitoring the ruminal pH and subacute ruminal acidosis (SARA) in cattle is described. This is done in order to reveal the possible application of this system for detection and pathophysiological research of SARA by continuous ruminal pH measurement. The possibility of using this system for assessment of the ruminal pH in SARA cattl...

When mixed ruminal bacteria were incubated with a pancreatic casein hydrolysate and free amino acids of a similar composition, rates of ammonia production were much greater for peptides than for amino acids. The pancreatic digest of casein was then fractionated with 90% isopropyl alcohol. Hydrophobic peptides which dissolved in alcohol contained an abundance of phenolic and aliphatic amino acid...

Five steam-flaked sorghum grain (SFSG) samples with bulk densities of 476, 412, 347, 309 and 283 g/liter made by adjusting tension between mill rollers and three reconstituted sorghum grain (RSG) samples with reconstitution times of 10, 20 and 30 d and a control sample were analyzed for gas production kinetics (rumen liquor fermentation) and enzymatic glucose release (amyloglucosidase). Protein...

The current study evaluated the effects of electron beam (EB; 10, 20, 30 and 40 kGy), urea and NaOH treatments on chemical composition, phenolic compounds, in vitro gas production and i n situ ruminal degradability of pistachio by-product (PB). The EB decreased (p < 0.01) neutral detergent fiber (NDF), acid detergent fiber (ADF) and acid detergent lignin (ADL) contents of PB. Treating PB by NaO...

Non-enzymatic browning was tested as a means of suppressing degradation of soybean meal (SBM) by ruminal microbes in five trials with in vitro ammonia release as the response criterion. Treatments imposed on SBM included reducing sugar source (xylose, glucose, fructose and lactose), reducing sugar level (1, 3 and 5 mol/mol SBM-lysine), pH (6.5, 8.5 and 10.0), dry matter (DM) content (65, 70, 75...