Seasonal Changes Of Rumen Microorganism Of The Tibetan Sheep Revealed With Real-Time PCR And PCR-DGGE

Tibetan sheep lives on Qinghai-Tibetan Plateau, which is the only unimproved, no-polluted areas of the world and supplied only natural grasses for Tibetan sheep. For these reasons, the rumen microbial of the Tibetan sheep is different from other ruminants such as cows, cattle and sheep that was house feeding. The purpose of this study was to much more comprehend the quantities of the rumen microbial of Tibetan sheep under difference seasons, further discover the change of the composed microbial populations, moreover, illuminating the effect of difference season on the quantity and the structure of microbial populations. In the future, the result of this study provided reliable information for manipulation of ruminal fermentation.Experiment1:The effect of season, In fact, that is still the effect of feedstuff, on ruminal microorganisms. Mix forage samples in grazing Tibetan sheep were collected during year of 2004-2004.The nutritive value of mix native forages consisting of sedge, grass, forb and shrub species harvested, and the forage intake in summer, autumn winter and spring from the Tibetan Plateau of China was assessed by using chemical, in sacco degradability and hand plucking analyses. The result showed that metabolizable energy value (ME) as estimated by in vitro gas production and chemical composition data decreased with maturity. The crude protein (CP) content and the ME of mix native forages in summer were the highest (ME, 11.49 MJ/kg; CP, 11.06%) and the lowest (ME, 6.00~6.86MJ/kg; CP, 4.94~6.3%) in spring and winter. on the contrary, the Neutral detergent fibre (NDF) and the Acid detergent fibre (ADF) in summer (NDF, 52.05%; ADF, 37.78%) were the lowest (NDF, 62.66~64.46%; ADF, 43.40~42.47%) in spring and winter. The dry mater digestibility (DMD) determined by in sacco digestion trials in the summer autumn and winter-spring were respectively 52.07%, 51.43%, and 50.28%~48.81%,which was significantly different respectively(p<0.05), and the DMD in summer was the highest. In the winter-spring and autumn, the CP intake of the grazing...