Abstract: A quantitative real-time PCR approach was used to determine the population densities of major ruminal cellulolytic bacterial species (Fibrobacter succinogenes, Ruminococcus albus and Ruminococcus flavefaciens) in rumen fluid and digesta of swamp buffalo (Bubalus bubalis). Four rumen-fistulated, male swamp buffalo were randomly assigned according to a 4x4 Latin square design to evaluate the effect of Phaseolus calcaratus Hay (PCH) supplementation. PCH contained 18.3% Crude Protein (CP) and 2.8% condensed tannins. Animals were given 0, 300, 600 and 900 g day-1 as supplements. All animals were given ad libitum access to rice straw while additional concentrate (12.6% CP) was given at 0.3% body mass and each period lasted for 21 days. At the end of each period, rumen fluid and digesta was collected at 0, 4 h post morning feeding. It was found that PCH supplementation increased these three cellulolytic bacteria F. succinogenes between 2.5 and 5.5x109, R. flavefaciens between 3.6 and 9.1x109, R. albus between 5.7 and 17.9x108 copies mL-1 at 0, 300, 600 and 900 g day-1 of supplementation, respectively. Moreover, at 4 h post-morning feeding, the populations of the two cellulolytic bacteria were higher than those found at 0 h post-morning feeding. It is most notable that R. flavefaciens and R. albus were the highest in population in the rumen of swamp buffalo, hence indicating high ability in utilizing high fibrous feeds.
Vongpasith Chanthakhoun and Metha Wanapat, 2010. Effect of Legume (Phaseolus calcaratus) Hay Supplementation on Rumen Cellulolytic Bacterial Populations in Swamp Buffaloes Investigated by the Real-Time PCR Technique. Journal of Animal and Veterinary Advances, 9: 1654-1659.