过瘤胃蛋氨酸对奶牛瘤胃微生物蛋白产量、产奶性能和氮排泄的影响  

Effects of Rumen-Protected Methionine on Ruminal Microbial Protein Production,Milk Performance and Nitrogen Excretion of Dairy Cows

作　　者：张成喜[1] 孙友德[2] 刘锡武[2] 孙国强[1] 

机构地区：[1]青岛农业大学动物科技学院,青岛266109 [2]青岛市畜牧兽医研究所,青岛266100

出　　处：《动物营养学报》2017年第5期1759-1766,共8页CHINESE JOURNAL OF ANIMAL NUTRITION

基　　金：基金项目 山东省现代农业产业技术体系牛产业创新团队(SDAIT-09-08)

摘　　要：本试验旨在研究过瘤胃蛋氨酸(RPMet)对奶牛瘤胃微生物蛋白(MCP)产量、产奶性能及氮排泄的影响。选取年龄、体重、胎次、产奶量、乳成分及泌乳期[(90±15)d]相近的荷斯坦奶牛40头,随机分为4组,每组10头,对照组和试验1组、2组、3组分别添加0、15、25和35 g/(d·头)RPMet。预试期15 d,正试期60 d。结果表明:1)各试验组瘤胃MCP的产量均极显著高于对照组(P<0.01),试验1组、2组、3组分别比对照组提高了13.10%、20.45%、16.23%。2)试验组产奶量显著或极显著高于对照组(P<0.05或P<0.01),试验1组、2组、3组分别比对照组提高了8.12%、13.32%、10.32%;RPMet能显著或极显著提高乳脂率和乳蛋白率(P<0.05或P<0.01),显著或极显著降低了乳体细胞数(P<0.05或P<0.01),以试验2组最低。3)在氮总排出量方面,各试验组均极显著低于对照组(P<0.01),试验1组、2组、3组分别比对照组降低了8.55%、17.49%、13.25%。由此可知,在本试验条件下,饲粮中添加RPMet可以显著提高奶牛瘤胃MCP产量,减少氮排泄,提高奶牛生产性能。综合各项试验指标,RPMet的最适添加量为25 g/(d·头)。This experiment was conducted to determine the effects of rumen-protected methionine （RPMet） on ruminal microbial protein （MCP） production, milk performance and nitrogen excretion of dairy cows. Forty Holstein lactating cows with similar age, body weight, parity, milk yield, milk composition and lactation period [（90±15） d] were randomly divided into 4 groups with 10 cows per group. The supplement level of RPMet in control and test groups 1, 2 and 3 was 0, 15, 25 and 35 g/（d·head）, respectively. The pretest lasted for 15 d, and the test lasted for 60 d. The results showed as follows： 1） ruminal MCP production in test groups 1, 2 and 3 was extremely significantly increased by 13.10%, 20.45% and 16.23% compared with control group （P〈0.01）, respectively. 2） Milk yield in test groups 1, 2 and 3 was significantly increased by 8.12%, 13.32% and 10.32% compared with control group （P〈0.05 or P〈0.01）, respectively; RPMet could significantly increase milk fat percentage and milk protein percentage （P〈0.05 or P〈0.01）, and could significantly reduce milk somatic cell count （P〈0.05 or P〈0.01）, especially test group 2 was the lowest. 3） Compared with control group, total nitrogen excretion in test groups was extremely significantly reduced （P〈0.01）, and was reduced by 8.55%, 17.49% and 13.25% in test groups 1, 2 and 3, respectively. It can be seen that the addition of RPMet to diets can significantly increase ruminal MCP production, decrease nitrogen excretion, and improve the performance of dairy cows under the present experimental conditions. The optimal dosage of RPMet was 25 g/（d·head）.

关 键 词：过瘤胃蛋氨酸 瘤胃微生物蛋白 产奶性能 氮排泄 

分 类 号：S816.7[农业科学—饲料科学]