不同牛场泌乳早期奶牛春季和夏季泌乳性能及血液生化指标的比较

摘要

为调查我国不同牛场奶牛的泌乳性能和血液生化指标随季节的变化情况,采集北京、滁州、哈尔滨、呼和浩特、乌鲁木齐和西安地区奶牛场泌乳早期奶牛(泌乳日龄,50 ～90 d)春季和夏季的奶样和血样,并对产奶量、乳蛋白、乳脂肪、乳总固形物、乳糖等泌乳指标,以及血液中的β-羟丁酸(β-HA)、非酯化脂肪酸(NEFA)、胆固醇(CHOL)、总蛋白(TP)、白蛋白(ALB)、尿素氮(BUN)、碱性磷酸酶(ALP)、谷草转氨酶(AST)、谷丙转氨酶(ALT)等血液生化指标进行测定,利用SAS 8.1对数据进行处理.结果显示,不同牛场奶牛的泌乳性能指标之间有显著的差别(P＜0.01),乳脂受到了季节变化的极显著影响(P＜0.01),牛场和季节的互作效应对于奶牛泌乳性能也有极显著的影响(P＜0.01)；血液指标中,除CHOL外的所有指标受到了牛场差异的影响(P＜0.01),而大部分指标(除ALP、AST外)随季节变化有显著的差异(P＜0.05),季节和牛场对NEFA等7种血液指标也存在显著的交互作用(P＜0.05).表明牛奶中的乳脂以及奶牛血液生化指标会受到季节变化的影响,但不同牛场奶牛的泌乳性能指标和血液中的NEFA、ALB、BUN等生化指标随季节转换的变化并不一致.%To investigate the variation of dairy cows' milk performance and plasma biochemical index in different farms between spring and summer, milk and plasma samples in spring and summer were collected from dairy cows in early lactation ( DIM ,50-90 d ) , which were screened from dairy farms in Beijing, Chuzhou, Harbin, Ho-hhot,Urumqi and Xi'an. Milk property,such as milk yield,protein,fat,total solid,lactose content in milk,and biochemical index in plasma, ?hydroxybutyrate ( (?HA) , nonesterified fatty acid ( NEFA) , cholesterol ( CHOL) , total protein(TP) .albumin (ALB) , blood urea nitrogen ( BUN ), alkaline phosphatase ( ALP) , aspartate amino transferase (AST) ,alanine amino transferase (ALT) ,for instance,were examined in this study. And data were processed by SAS 8.1. Results showed,dairy cows from different dairy farms had significant variation in milk performance (P <0.01) , only milk fat content was influenced by season transition significantly (P <0. 01), prominent interaction between season and dairy farm also existed in milk performance (P < 0. 01). Biochemical parameters in plasma, all but CHOL were affected by dairy farm ( P <0.01) ,most of items ( except ALP, AST) varied remarkably ( P < 0. 05 ) as season changed, NEFA and other 7 indexes were obedient to interaction of season and dairy farm ( P < 0. 05 ). It was suggested that milk fat and dairy cow plasma biochemical parameters were subjected to season remarkably, but in-consistent variation emerged on corresponding parameters of dairy cows from different farms.