摘要
本试验旨在研究我国北方农区典型饲粮条件下,瘤胃保护性蛋氨酸(RPMet)和瘤胃保护性赖氨酸(RPLys)补饲量对高产泌乳荷斯坦奶牛生产性能及血浆生化指标的影响。试验采用随机区组设计,选用160头泌乳高峰期、产奶量30 kg/d的荷斯坦奶牛,随机分为4组,每组40头,对照组饲喂基础饲粮,3个试验组在饲喂基础饲粮的同时,补饲RPMet和RPLys,2者补饲量分别为13和6 g/d(M13+L6组)、43和98 g/d(M43+L98组)、74和190 g/d(M74+L190组)。预试期10 d,正试期50 d。结果表明:1)补饲RPMet和RPLys对奶牛的干物质采食量没有显著影响(P>0.05)。2)M74+L190组的产奶量、乳脂产量、乳糖产量显著高于对照组和M13+L6组(P<0.05),乳尿素氮浓度显著低于对照组和M13+L6组(P<0.05);M43+L98和M74+L190组的乳蛋白产量显著高于M13+L6组(P<0.05)。3)与对照组相比,M74+L190组血浆赖氨酸浓度显著提高(P<0.05),血浆尿素氮浓度显著降低(P<0.05);M43+L98和M74+L190组的血浆蛋氨酸和甘油三酯浓度显著提高(P<0.05)。综上所述,在我国北方典型饲粮条件下,补饲RPMet和RPLys提高了泌乳高峰期奶牛的生产性能,产奶30 kg/d泌乳高峰期奶牛的RPMet和RPLys适宜补饲量分别为74和190 g/d。
This experiment was conducted to investigate the effects of the supplementatl levels of rumen-protec-ted methionine （ RPMet） and lysine （ RPLys） on performance and plasma biochemical indices of lactating Hol-stein cows under typical dietary condition in northern China.One hundred and sixty lactating Holstein cows in peak lactation period and with milk yield produced about 30 kg/d were selected and randomly allotted to four groups with 40 cows in each group.Cows in control group were fed a basal diet, and those in experimental groups were fed the basal diet supplemented with 13 g/d RPMet＋6 g/d RPLys （ M13＋L6 group） , 43 g/d RPMet＋98 g/d RPLys （ M43＋L98 group） , and 74 g/d RPMet＋190 g/d RPLys （ M74＋L190 group） ,re-spectively.The experiment consisted of a 10-day pre-experimental period and a 50-day experimental period. The results showed as follows：1 ） dietary supplementation of RPMet and RPLys had no significant effects on dry matter intake （ P〉0 .05 ） .2 ） Milk yield, milk fat yield and lactose yield in M74＋L190 group were sig-nificantly higher than those in control group and M13 ＋L6 group （ P 〈0 .05 ） , while milk urinary nitrogen concentration was significantly lower than that in control group and M13 ＋L6 group （ P〈0 .05 ） .3 ） Com-pared with control group, plasma lysine concentration in M74＋L190 group was significantly increased （ P〈0 .05 ） , while plasma urinary nitrogen concentration was significantly decreased （ P〈0 .05 ）; plasma methio-nine and triglyceride concentrations in M43＋L98 and M74＋M190 groups were significantly increased （ P〈0.05）.In conclusion, under the typical dietary condition of northern China, the supplementation of RPMet and RPLys can improve performance of lactating cows in peak locating period, and the suitable supplemental levels of RPMet and RPLys for cows produced about 30 kg/d milk are 74 and 190 g/d, respectively.
出处
《动物营养学报》
CAS
CSCD
北大核心
2014年第2期363-370,共8页
CHINESE JOURNAL OF ANIMAL NUTRITION
基金
国家农业(奶业)产业技术体系
