4Donmez N, Karsh M A,Clnar A, et al.2003.The effects of different silage additives on rumen protozoan number and volatile fatty acid concentration in sheep fed eom silage [J].Small Ruminant Research,48: 227-231.
5Dore au M, Ferchal E, Beckers Y. 1997.Effects of level of intake and of available volatile fatty acids on the absorptive capacity of sheep rumen [ J ].Small Ruminant Research,25:99-105.
6Bannink A,DeVisser H, Klop A ,et al. 1997.Causes of inaccurate prediction of volatile fatty acids by simulation models of rumen function in lactating cows [J].J Theor Biol,189:353-366.