• Asian-Australasian Journal of Animal Sciences
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• v.26 no.11
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• pp.1583-1591
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• 2013

The objective of this study was to investigate microbial population in the rumen of dairy steers as influenced by supplementing with dietary condensed tannins and saponins and different roughage to concentrate ratios. Four, rumen fistulated dairy steers (Bos indicus) were used in a $2{\times}2$ factorial arrangement in a $4{\times}4$ Latin square design. The main factors were two roughage to concentrate ratios (R:C, 60:40 and 40:60) and two supplementations of rain tree pod meal (RPM) (0 and 60 g/kg of total DM intake). Chopped 30 g/kg urea treated rice straw was used as a roughage source. All animals received feed according to respective R:C ratios at 25 g/kg body weight. The RPM contained crude tannins and saponins at 84 and 143 g/kg of DM, respectively. It was found that ruminal pH decreased while ruminal temperature increased by a higher concentrate ratio (R:C 40:60) (p<0.05). In contrast, total bacterial, Ruminococus albus and viable proteolytic bacteria were not affected by dietary supplementation. Numbers of fungi, cellulolytic bacteria, Fibrobactor succinogenes and Ruminococus flavefaciens were higher while amylolytic bacteria was lower when steers were fed at 400 g/kg of concentrate. The population of Fibrobactor succinogenes, was found to be higher with RPM supplementation. In addition, the use of real-time PCR technique indicated that the population of protozoa and methanogens were decreased (p<0.05) with supplementation of RPM and with an increasing concentrate ratio. Supplementation of RPM and feeding different concentrate ratios resulted in changing the rumen microbes especially, when the animals were fed at 600 g/kg of concentrate and supplemented with RPM which significantly reduced the protozoa and methanogens population.

• Journal of Animal Science and Technology
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• v.51 no.1
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• pp.45-52
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• 2009

This experiment was conducted to observe the effects of anaerobic cellulolytic bacteria culture (Ruminococcus flavefaciens H-20 and Fibrobactor succinogenes H-23) on in vivo ruminal fermentation characteristics in Hanwoo heifers. Four ruminally cannulated Hanwoo heifers ($221\pm7.5kg$) receiving a basal diet containing 3 kg of mixture hay (tall fescue and ochardgrass) and 2 kg of concentrate per day were in a $4\times4$ Latin square with 21-day periods. Treatments were the basal diet without the culture additive (control), the basal diet plus 50 ml/day of bacteria culture of H-20 and H-23 (1%), 150 ml/day of H-20 and H-23 (3%), and 250 ml/day of H-20 and H-23 (5%). In the whole experimental periods, ruminal pH did not differ between treatments. However, the concentration of ruminal ammonia-N was increased in the 3% treatment relative to control and the 1% treatment at 1 hr post-feeding (p<0.05). Avicelase and CMCase (carboxymethyl cellulase) activities in rumen fluid showed no significant difference among treatments. However, xylanase activity was higher in the 5% (119.49, xylose ${\mu}mol$/ml/min) than the 3% treatment (71.02, xylose ${\mu}mol$/ml/min) at 0 hr post-feeding (p<0.05). Concentrations of ruminal total VFA, acetate, propionate and valerate were unaffected by treatments, while butyrate was higher in the 3% treatment (24.48 mM) than control (15.71 mM) at 1 hr post-feeding (p<0.05). Results indicate that minimum 3% inclusion of cellulolytic bacteria cultures improved ruminal fermentation, especially ammonia-N concentration and butyric acid production.