改变日粮蛋白质和赖氨酸含量对奶牛产奶性能和氮利用及代谢激素的影响  

Effects of changing diet protein and lysine content on milk performance,nitrogen utilization and blood metabolic hormones for dairy cows

作　　者：孙建全[1] 赵红波[1] 刘春林[2] 游伟[1] 王星凌[1] 

机构地区：[1]山东省农业科学院畜牧兽医研究所,山东济南250100 [2]山东科技大学电气信息系,山东济南250031

出　　处：《南京农业大学学报》2011年第2期124-128,共5页Journal of Nanjing Agricultural University

基　　金：国家奶牛行业专项(nyzx07-036-01);山东省科技厅攻关项目(2008GG10009022);山东省重大创新项目"奶牛精细饲养管理应用技术研究"

摘　　要：为观察不同日粮蛋白质(CP)和赖氨酸(Lys)含量对奶牛产奶性能、氮利用和血液代谢激素的影响,试验采用4×4拉丁方设计,选择4头经产中国荷斯坦奶牛,随机接受4种日粮处理:12.5%CP和0.44%Lys的日粮1;12.6%CP和0.58%Lys的日粮2;14.1%CP和0.45%Lys的日粮3;14.1%CP和0.60%Lys的日粮4。试验分为4期,每期18 d。第1天至第14天为适应期,第15天至第18天为收集期。结果表明:日粮4和日粮2的产奶量显著高于日粮3和日粮1(P<0.05),乳蛋白率也略高于日粮3和日粮1(P>0.05);日粮4和日粮2的氮利用率和奶氮排出量明显高于日粮3和日粮1(P<0.05);日粮4和日粮2的尿素氮(SUN)浓度明显低于日粮3和日粮1(P<0.05);日粮4和日粮2的胰岛素和催乳素浓度明显高于日粮3和日粮1(P<0.05)。赖氨酸含量相同时,日粮CP含量为14.1%或12.6%,奶牛产奶性能不受影响,乳氮产量增加,氮利用率提高;当奶牛日粮赖氨酸含量从0.60%降到0.45%,尽管蛋白质含量相同,但奶牛产奶量下降,乳蛋白略呈下降趋势,乳氮产量降低,氮利用率降低。A nitrogen balance experiment was performed to characterize the effects of decreasing dietary crude protein（CP）from 14.1% to 12.6% and dietary lysine from 0.60% to 0.45% on milk yield,N utilization and blood metabolic hormones for lactating cows.Four multiparous Holstein lactating cows were used in a 4×4 Latin Square.Four diets were formulated to contain 12.5% CP and 0.44% Lys（Diet 1）,12.6% CP and 0.58% Lys（Diet 2）,14.1% CP and 0.45% Lys（Diet 3）and 14.1% CP and 0.60% Lys（Diet 4）.Each lactating cow had 4 experimental periods and each period had a 14 d adaptation,followed by a 4 d total milk,faecal and urine collection.Blood samples were taken in the last 2 days of the collection.During the experiment,the milk production of cows for Diet 4 and Diet 2 were similar（P〉0.05）,but higher than Diet 3 and Diet 1（P〈0.05）.Milk composition,especially milk protein for Diet 4 and Diet 2 had a rise trend compared with Diet 3 and Diet 1（P〉0.05）.N utilization and milk N excretion for Diet 4 and Diet 2 were higher than Diet 3 and Diet 1（P〈0.05）.Serum urea nitrogen（SUN）concentration for Diet 4 and Diet 2 was lower than Diet 3 and Diet 1（P〈0.05）while the concentration of insulin or prolactin for Diet 4 and Diet 2 was higher than Diet 3 and Diet 1（P〈0.05）.Dietary protein quality could manipulate hormone secretion and SUN concentration of dairy cows and modify their performance.Therefore,the cows had the similar milk production and slightly higher milk protein,improved N utilization and increased milk N excretion when dietary Lys content was 0.60%,though dietary CP decreased from 14.1% to 12.6%;the cows decreased the milk production and milk protein,milk N excretion and N utilization when dietary Lys decreased from 0.60% to 0.45%,no matter how dietary CP changed.

关 键 词：奶牛 日粮 蛋白质 赖氨酸 产奶性能 氮利用率 代谢激素 

分 类 号：S816.32[农业科学—饲料科学]