Effect Of Tannic Acid On In Vitro Remen Fermentation Characteristics And Methane Emission Of Sheep

The present research was conducted to study the effect of tannic acid on rumen fermentation and methane production in vitro syringe system, the microbial degradation by rumianl fluid of sheep had no prior exposure to tannin-rich diets, and tannic acid metabolites were analysed by thin-layer chromatography. By developing the optional measurement condition for ruminal fermentation products and comparing the effects of different levels of tannic acid on fermentation and methane production, the proper adding levels of tannic acid in vitro was established. We also examined the characteristics of rumen fluid fermentation and methane production of tannic acid (TA) unsupplemented or supplemented with different forage : concentrate (F : C) ratios by using gas production method. The main results are shown as follows:1. By using the AT SE-30(30m×0.32mm×0.53um)and, ZB-FFAP(7GH-G009-11)(30m×0.25mm×0.25um)FID and nitrogen as the carrier, the optimal measurement condition for methane and volatile fatty acid were established respectively. This method proved not only to be stable, practical, fast and easy to operate but also better in repetition and exact in accuracy.2. A pooled sample of rumen liquor was collected from four adult sheep; these animals were stall fed on a diet of alfafa grass and corn. Water was coffered freely. The animals had not been exposed to tannin rich diet. Tannic acid metablites were analysed by thin-layer chromatography. The gas volume was increased and ammonia concentration decreased in the presence of tannic acid. The differences were significant (p<0.01) except between control and control +tannic acid at 24 h. The decrease in ammonia concentrations was related to increase in gas volume; being more apparent after 24 h. Gallic acid and pyrogallol were detected in the samples collected at 24 h of incubation. Gallic acid or residual tannic acid could not be detected at 48 h and 72 h. Pyrogallol and resorcinol were the only metabolites which could be detected in the samples collected at 48 h and 72 h. No metabolites of tannic acid were found in the control set which contained autoclaved rumen liquor along with tannic acid.3. The effects of tannic acid on rumen fermentation and methane emission were examined in Menke's syringe system. Buffer solutions and rumen liquor/buffer (1:1) were prepared according to these workers. In the experiment set, 100 ml graduated glass syringes(Hberle, Germany), prewarmed at 39℃, were taken and 30 ml buffered rumen...