The Effects Of RDP,NPN On Ruminal Fermentation And Ruminally Nutritional Digestibility In Vitro

The target of ruminantly proteinic nutrition is using least protein to meet optimizational growth of ruminally microorganism crude protein, and ruminant put up perfect procreative capability. In order to achieve optimal efficiency of crude protein in use, feeding protein and NPN were selected. One side origin and quantity of protein exactly meet growth of microorganism crude protein, but RDP of crude protein didn't exceed; on the other hand quantity and species of degradable RDP meet quantity and ration of absorbable AA in small intestine which attain optimal needShort period fermentational technology was used in this experimentation in vitro. In the condition of same energy and nitrogen, the experimental design was a single factorial arrangement of treatments, RDP were percent 11.38%,9.83%,8.38%,7.58% of air-dry, to study effect of RDP on ruminally microbial fermentation and nutritional digestibility. The result indicated that ruminal pH declined significantly with prolong time of fermentation, but it still in the natural change extension. Effects of RDP on ruminal pH was significant, increasing dietary RDP improved ruminal pH significantly (P<0.05).In three phase incubative period,effects of RDP on ruminal NH3-N concentration showed that NH3-N concentration was dropped when stimulant rumen fermented until 24 hour, and NH3-N concentration increased when stimulant rumen fermented until 48 hour. Effects of RDP on ruminal NH3-N concentration was significant, increasing dietary RDP improved ruminal NH3-N concentration significantly (P<0.05).RDP and ruminal NH3-N concentration showed plus linear correlation, expression was y(NH3-N concentration)=2.1471x(RDP level). Ruminally microbial growth has a degree to need of RDP, exceeding this degree, ruminally microbial growth will be confined. In this experiment, expression of RDP and ruminally bacterial N was y(ruminally bacterial N concentration)=-0.6519(RDP level)2+13.387(RDP level)-58.907(R2=0.8103,n=4,P<0.01).In this experimentation, optimal RDP was 9.83 percentage of air-dry diet. Effects of RDP on ruminal digestibility of DM have remarkable difference (P<0.05) at fermentation 12 and 24 hour, increasing RDP level improved ruminal digestibility of DM. Effects of RDP on ruminal digestibility of DM have not remarkable difference (P>0.05) at fermentation 48hour.