包被胍基乙酸对奶牛泌乳性能和瘤胃发酵的影响

Effects of Coated Guanidinoacetic Acid Supplementation on Lactation Performance and Ruminal Fermentation in Holstein Dairy Cows

为研究包被胍基乙酸(CGA)对奶牛泌乳性能、养分消化和瘤胃发酵的影响,将48头荷斯坦奶牛按随机区组设计分4组,分别以CGA的形式补充胍基乙酸(GA)0、0.3、0.6 g/kg和0.9 g/kg,进行80 d的饲养试验。结果表明,与不添加组相比,0.6 g GA/kg组,乳脂矫正奶产量、养分消化率、瘤胃总挥发性脂肪酸浓度和微生物数量显著提高(P<0.05),瘤胃pH和乙酸/丙酸值显著降低(P<0.05)。综上可知,CGA 0.6 g GA/kg能提高奶牛产奶量。

The study evaluated the effects of coated guanidinoacetic acid(CGA)supplementation on lactation performance and ruminal fermentation in dairy cows.Forty Holstein dairy cows were assigned in a randomized block design to four groups supplementing with CGA at 0,0.3,0.6 g/kg and 0.9 g/kg of guanidinoacetic acid(GA),respectively.The experimental period was 80 days with 20 days for adaptation and 60 days for data and sample collection.When comparing with the unsupplemented group,fat corrected milk yield,nutrient apparent digestibility and ruminal total volatile fatty acids concentration,propionate molar proportion and the populations of total bacteria,protozoa,fungi,primary cellulolytic bacteria and amylolytic bacteria were greater(P<0.05),but ruminal pH,acetate molar proportion and acetate to propionate ratio were lower(P<0.05)for supplementing CGA at 0.6 g GA/kg.The results indicated that supplementation with CGA at 0.6 g GA/kg had the potential to improve lactation performance and ruminal fermentation in dairy cows.