GRANT R J,MERTENS D R.Influence of buffer pH and raw maize starch addition on in vitro fiber digestion kinetics [J].Journal of Dairy Science,1992,75:2762-2768.
MCDONALD P,EDWARDS R A,GREENHALGH J F D,et al.Animal nutrition[M].5th ed.Essex:Longman Scientific and Technical,1996:607.
[4]
DHIMAN T R,SATTER L D.Yield response of dairy cows fed different proportions of alfalfa silage and maize silage[J].Journal of Dairy Science,1997,80:2069-2082.
MENKE K H,RAAB L,SALEWSK I,et al.The estimation of the digestibility and metabolizable energy content of ruminant feeding stuffs from the gas production when they are incubated with rumen liquor in vitro[J].Journal of Agricultural Science,1979,93:217-222.
[14]
RSKOV E R,MCDONALD I.The estimation of protein degradation in the rumen from incubation measurements weighted according to the rate of passage[J].Journal of Agricultural Science,1979,92:499-503.
[15]
SEARLE L P.The berthelot or indophenol reaction and its use in the analytical chemistry of nitrogen:a review[J].Analyst,1984,109:549-568.
LEES J A,OLDHAM J D,HARESIGN W,et al.The effect of pattern of rumen fermentation on the response by dairy cows to dietary protein concentration[J].British Journal of Nutrition,1990,63:177-186.