不同能量水平日粮对肉牛瘤胃微生物氨基酸组成的影响

:选用 1 2头杂种黄牛研究了不同能量水平 ( 5 2 0、6 2 7、7 87MJ/kg)的日粮对存在于瘤胃液中的微生物 (liquid associatedmicroorganisms,LAM)和在瘤胃中与饲料颗粒紧密结合的微生物 (solid associatedmi croorganisms,SAM)的氨基酸组成的影响。日粮由玉米、棉籽饼和玉米秸秆组成。结果表明 :能量水平对LAM中的Leu(P <0 0 0 1 )、Phe(P <0 0 1 )、Lys(P <0 0 0 1 )、His(P <0 0 0 1 )、Arg(P <0 0 0 1 )、Asp(P <0 0 0 1 )和Gly(P <0 0 0 1 )等 7种氨基酸的含量影响显著 ;对SAM中的Thr(P <0 0 5)、Val(P <0 0 5)、Lys(P <0 0 5)和Met(P <0 0 5)等 4种氨基酸的含量影响显著。不同组分的瘤胃微生物中 ,有 6种氨基酸的组成显著不同。在LAM中Glu(P <0 0 5)、Ala(P <0 0 0 1 )和Cys(P <0 0 0 1 )的含量明显高于在SAM中的含量而Leu(P <0 0 5)、His(P <0 0 1 )和Pro(P <0 0 0 1 )的含量则相反。另外His(P <0 0 5)、Arg(P <0 0 1 )、和Asp(P <0 0 1 )等 3种氨基酸在LAM和SAM中的相对组成受日粮能量水平的影响。结论 :不同组分瘤胃微生物的氨基酸组成有所差异 ,日粮能量水平对瘤胃微生物的氨基酸组成有明显影响

Effect of Dietary Energy Level on Amino Acid Composition of Rumen Liquid-associated Microorganisms and Solid-associated Microorganisms

Twelve steers were used to examine the effect of amino acid(AA)composition of rumen liquid associated microorganisms(LAM) and solid associated microorganisms(SAM) as affected by dietary energy level(5.20,6.27 and 7.87MJ integrated net energy/kg DM,respectively).Diets were corn,cottonseed meal and corn straw.Energy level affected AA composition of Leu(P<0.001)、Phe(P<0.01)、Lys(P<0.001)、His(P<0.001)、Arg(P<0.001)、Asp(P<0.001)and Gly(P<0.001)in LAM and Thr(P<0.05)、Val (P<0.05) 、Lys(P<0.05)and Met(P<0.05)in SAM.Significant differences of AA composition between LAM and SAM were observed for 6 out of 17 AA examined.And the relative composition of 3 AA affected by dietary energy level was also observed.