日粮中高粱替代玉米对绵羊瘤胃发酵的影响

Effect of sorghum in replacing corn in the diets on rumen fermentation in sheep

为了研究绵羊日粮中高粱不同比例替代玉米对瘤胃发酵的影响,试验采用24只德国美利奴3月龄断奶羔羊按试验要求随机分成4组,每组6只,4个处理分别为精料中能量饲料完全由玉米组成(A组)、高粱替代1/3玉米(B组)、高粱替代2/3玉米(C组)和高粱完全替代玉米(D组),研究绵羊采食后对瘤胃发酵参数的影响。结果表明:A、B、C、D各组间pH值差异不显著(P>0.05)。乙酸、丙酸和总挥发性脂肪酸浓度C组最高,D组最低,但三者在各组间差异不显著(P>0.05);丁酸浓度A组最低,C组最高,各组间差异不显著(P>0.05)。瘤胃氨态氮平均浓度C组显著高于B组(P<0.05),但与A、D组差异不显著(P>0.05)。说明高粱作为能量饲料完全或部分替代绵羊日粮中玉米对瘤胃发酵没有负面影响,高粱2/3替代玉米有促进瘤胃发酵的趋势。

To study the effects of different proportions of sorghum in replacing corn in the diets on rumen fermentation in sheep ,24 German Meri- no lambs weaned at three months of age, were randomly divided into 4 groups of each six lambs according to the experiment requirement. The lambs were fed the concentrated energy feed with four treatments for investigating the effects of the treatments on lumen fermentation parameters, including corn entirely used as energy feed （group A） , 1/3 sorghum in replacing corn（ group B） , 2/3 sorghum in replacing corn（ group C）, sorghum in replacing whole corn （ group D）. The results showed that there were no significant differences （ P 〉 0.05 ） in the pH values between each group; The concentrations of acetic acid, propionic acid and total volatile fatty acid （VFA） were the highest in the group C, and those in the group D were the lowest, but there were no significant differences in the concentrations of the three acids （P 〉 0.05） between each group. The concentration of butyric acid in the group A was the lowest, and that in the group C was the highest, and there were also no significant differences （ P 〉 0.05 ） in the concentration of butyric acid between each group. The average concentration of rumen ammonia nitrogen in the group C was significantly higher （P 〈 0.05 ） than that in the group B,but there were no significant differences （P 〉 0.05 ） compared with the group A and group D. The results indicate that sorghum as energy feed can be used to totally replace or partially replace corn in sheep diets with- out negative effects oda rumen fermentation, there is a tendency to promote lumen fermentation with 2/3 sorghum in replacing corn.