不同NDF/NFE比的日粮对山羊瘤胃发酵参数影响的研究

Effects of the Ratio of NDF to NFE on Ruminal Internal Environment Parameters of the Goats

利用4只(35±2.5)kg装有瘤胃瘘管的徐淮白山羊,采用拉丁方试验设计,饲喂NDF/NFE分别为1.46(A组)、1.2(5 B组)、1.0(3 C组)、0.8(2 D组)的4种日粮,研究其对瘤胃内环境参数的昼夜动态变化规律的影响。结果表明:①瘤胃pH随NDF/NFE的降低而降低,由A组的6.37降至D组的5.86;②乙酸浓度以B组最高,极显著(P<0.01)高于A、C和D组,A、C、D 3组则依次降低(P>0.05);丙酸浓度以B、D两组较高,极显著(P<0.01)高于A和C组;丁酸浓度随NDF/NFE降低而升高,D组最高,极显著(P<0.01)高于C和B组;总VFA浓度B组最高,极显著(P<0.01)高于D组,显著(P<0.05)高于A、C组;乙酸/丙酸比随NDF/NFE比的降低而减小,A组极显著(P<0.01)大于B、C和D组;③瘤胃氨态氮平均浓度随日粮NDF/NFE比的降低而升高,由A组的8.37mg/dL升至D组的13.71mg/dL。

Four Xuhuai goats fitted with rumen fistulae were used in a 4× 4 latin square design to determine the effects of different neutral detergent fiber to N-free extract ratios（NDF/NFE） on the ruminal internal environment parameters. The NDF/NFE were 1.46（A）, 1.25（B）, 1.03（C）, 0.82（D）, respectively. The results showed that： ①Decreasing NDF/NFE decreased ruminal pH. The average pH decreased from 6.37 in group A to 5.86 in group D; ②The highest acetate con-centration was observed in group B, much higher than that in group A, C and D （P〈0.01）, in which concentration decreased orderly（P〉0.05）. Propionate concentrations were higher in group B and D than that in group A and C（P〈0.01）. Butyrate concentration increased orderly from group A to D. That in group D was much higher than that in group B and C（P〈0.01）. The level of total volatile fatty acids（TVFA） in group B was much higher than that in group D, A and C. Acetate to propionate ratio （C2/C3） decreased orderly as NDF/NFE ratio decreased. There were no significant differences among group B, C and D except for A; ③Lower NDF/NFE increased ammonia-N （NH3-N） concentration, which increased from group A to group D.