半胱胺和过瘤胃蛋氨酸不同组合对奶牛血液生化指标和养分消化率的影响

为研究半胱胺(CS)和过瘤胃蛋氨酸(RPMet)不同水平组合对奶牛血液生化指标和养分消化率的影响,试验选取体重、胎次、产奶量及泌乳期相近的荷斯坦奶牛40头,随机分为10组,每组4头。对照组(C组)饲喂基础饲粮,试验组补饲不同水平组合的CS和RPMet。CS分别添加13(L)、15(M)、17(H)g/(d·头);RPMet分别添加23(L)、25(M)、27(H)g/(d·头)。预试期15 d,正试期60 d。结果表明:HL组血清白蛋白含量比C组提高9.55%(P <0.01),ML、MH、HM、HH组比C组提高5.82%、5.92%、7.37%、6.96%(P <0.05)。LH、ML、MM、MH、HL、HM、HH组血清尿素氮浓度比C组降低7.27%、8.01%、8.90%、8.46%、9.50%、8.75%、8.16%(P <0.05)。各试验组干物质消化率比C组提高1.19%、4.36%、2.08%、2.68%、4.04%、1.59%、6.00%、1.50%、5.60%(P <0.01)。MM、HL、HH组酸性洗涤纤维消化率比C组提高19.74%、20.39%、14.47%(P <0.01)。综合考虑上述指标,在本试验设计条件下,以HL组,即CS 17 g/(d·头)、RPMet 23 g/(d·头)为最佳添加组合。

Effects of combination of cysteamine and rumen-protected methionine on blood biochemical parameter and nutrient digestibility of dairy cows

This experiment was conducte to determine the effects of different combinations of cysteamine(CS) and rumen-protected metnionine(RPMet) on blood biochemical parameter and nutrient digestibility of dairy cows. 40 holstein cows with similar body weight,birth order,milk yield and lactation days were selected and randomly divided into 10 groups. The control group(C group) was fed basic diet,while the test group was supplemented with CS and RPMet at different levels. The addition level of CS was 13(L),15(M),17(H) g/(d·head). The addition levels of RPMet were 23(L),25(M) and 27(H) g/(d·head). The pre-experiment period was 15 days and the formal experiment period was 60 days.The results showed that the serum albumin content of HL group was significantly higher than that of C group(P < 0.01),and the ML,MH,HM,HH group was significantly higher than that of C group(P < 0.05). The serum urea nitrogen concentration of LH,ML,MM,MH,HL,HM,HH group was significantly lower than that of C group(P < 0.05). The dry matter digestibility of each experimental group was significantly higher than that of C group(P < 0.01). The digestibility of neutral washing fiber in MM,HL,HH group was significantly higher than that in C group(P <0.01). After comprehensive consideration of various indicators,HL group,CS 17 g/(d·head),RPMet 23 g/(d·head) was the best combination.