The effects of essential oils isolated from Douglas fir needles on sheep and deer rumen microbial activity were tested by use of an anaerobic manometric technique. Rumen microorganisms were obtained from a sheep which had been fed mainly on alfalfa hay and dried range grass. One deer used in this study had access to Douglas fir trees the year around, whereas the other deer had no access to Doug...

Bio-hydrogenation of C18-unsaturated fatty acids released from the hydrolysis of dietary lipids in the rumen, in general, occurs rapidly but the range of hydrogenation is quite large, depending on the degree of unsaturation of fatty acids, the configuration of unsaturated fatty acids, microbial type and the experimental condition. Conjugated linoleic acid (CLA) is incompletely hydrogenated prod...

This experiment was conducted to investigate the effect of lemongrass [Cymbopogon citratus (DC.) Stapf.] powder (LGP) on rumen ecology, rumen microorganisms, and digestibility of nutrients. Four ruminally fistulated crossbred (Brahman native) beef cattle were randomly assigned according to a 4 x 4 Latin square design. The dietary treatments were LGP supplementation at 0, 100, 200, and 300 g/d w...

The formation of hydroxystearic acid (HSA) and ketostearic acid (KSA) from oleic acid transformation has been documented in a variety of microbial species, including several isolated from the rumen of domesticated ruminant species. However, their ruminal production rates have not been established as influenced by fatty acid source. Dosing continuous cultures of mixed ruminal microorganisms with...

effects of different levels of cadmium (0.1, 1, 2, 4, 8, 16, 32, 64, 128, 256 mg/l of culture medium) were evaluated using gas production technique. in the glass vials used to measure gas production 30 mg of buffered rumen fluid (2:1 ratio of rumen fluid: buffer) poured in glass and cultured at 38.6 temperature. volume and pressure of produced gas were measured with syringes and digital pressur...

Research on rumen microorganisms has contributed greatly to our understanding of anaerobic microbial ecosystems, and has also influenced feeding practices and nutritional modelling with ruminants. However, it can be argued that rumen microbiology has not yet fulfilled its true potential. Growth-promoting ionophores, antibiotics and microbial feed additives were introduced before their microbiol...

The effects of probiotics, yucca extract, monensin and L-cysteine on rumen methanogenesis were determined by in vitro incubation using mixed bovine rumen microorganisms with ground Bermuda grass hay as a substrate. Two forms of probiotics, yucca extract, monensin and L-cysteine were tested during 24 hour anaerobic incubations. Methane and carbon dioxide production and fermentation characteristi...