稀土和过瘤胃蛋氨酸不同组合对奶牛血液生化指标的影响

试验旨在研究不同稀土(RE)和过瘤胃蛋氨酸(RPMet)添加水平组合对奶牛血液生化指标的影响。选取60头体重(650±30)kg、胎次(2~3)胎、产奶量(30.06±3.34)kg、泌乳天数(90±20)d的荷斯坦奶牛,随机分成10组,每组6头。对照组(C)饲喂基础饲粮,试验组补饲不同水平组合的RE和RPMet。RE的添加水平为20.5(L)、23.0(M)和25.5 g/(头·d)(H);RPMet的添加水平为22.5(L)、25.0(M)和27.5 g/(头·d)(H),共组成LL、LM、LH、ML、MM、MH、HL、HM和HH 9个试验组。预试期15 d,正试期60 d。结果表明:LM、ML、MH、HL、HM、HH组总蛋白含量极显著高于C组(P<0.01);MH组白蛋白含量极显著高于C组(P<0.01);ML、HL组球蛋白含量显著高于C组(P<0.05);MM、MH组尿素氮含量极显著低于C组(P<0.01);MH、HL、HM、HH组生长激素含量显著高于C组(P<0.05)。在试验设计条件下,综合考虑上述指标,以MH组,即RE 23.0g/(头·d)、RPMet 27.5 g/(头·d)为最佳添加组合。

Effect of combination of rare earth and rumen-protected methionine on blood biochemical parameter of dairy cows

The experiment was to explore the effect of different combinations of RE and RPMet on blood biochemical parameter of dairy cows.Sixty Holstein cows with similar body weight(650±30)kg,parity(2~3),milk yield(30.06±3.34)kg,lactation period(90±20)d were divided into ten groups,and each group with six cows.The group C was fed with basic fodder,and experimental groups were supplemented with different combinations of RE and RPMet.The addition levels of RE were 20.5(L),23.0(M),25.5 g/(head·d)(H).The addition levels of RPLys were 22.5(L),25.0(M),27.5 g/(head·d)(H),consisting of nine test groups of LL,LM,LH,ML,MM,MH,HL,HM,HH.The pre-experiment period was 15 days and the formal experiment period was 60 days.The results showed that the total protein contents of LM,ML,MH,HL,HM,HH were significantly higher than C(P<0.01).The albumin content of MH was significantly higher than C(P<0.01).The globulin contents of ML and HL were significantly higher than C(P<0.05).The urea nitrogen contents of MM,MH were significantly lower than C(P<0.01).The GH contents of MH、HL、HM、HH were significantly higher than C(P<0.05).After comprehensive consideration of various indicators,under the test condition,the MH group RE 23 g/(head·d)and RPMet 27.5 g/(head·d)were the best addition combinations.