酮病奶牛血液生化指标和肝脏病理变化分析

Analysis of Blood Biochemical Indices and Liver Pathological Lesions in Ketosis Cows

为了解云南省某集约化养殖场奶牛酮病的发病情况,分析围产期酮病奶牛与健康奶牛相关血液指标和肝脏的变化,为奶牛酮病的防控及临床诊治提供理论依据。随机选择胎次为2胎~4胎的荷斯坦奶牛40头,跟踪采集产前5 d、生产当天、产后5 d和10 d的血液样品,根据β-羟丁酸(BHBA)浓度将奶牛分为健康组和酮病组。选取酮病组中因酮病被淘汰或死亡的奶牛,取肝组织制作病理切片。结果显示,酮病组奶牛与健康组奶牛相比,β-羟丁酸(BHBA)在产后5 d和10 d极显著升高(P<0.01),血糖(GLU)在产后5 d和10 d显著降低(P<0.05),游离脂肪酸(NEFA)和天门冬氨酸转移酶(AST)在产后10 d极显著升高(P<0.01),甘油三酯(TG)在产后10 d显著升高(P<0.05),对氧磷酶(PON-1)在产后10 d显著降低(P<0.05)。肝脏病理切片显示,与健康奶牛相比,酮病奶牛的肝脏组织结构异常,肝细胞发生脂肪变性,胞浆内出现大小不等的脂滴,脂肪蓄积严重。结果表明,该场奶牛酮病发病率为47.5%,多发于产后10 d,肝脏功能指标异常,肝脏脂肪蓄积严重,病变明显,存在潜在被淘汰风险。

In order to investigate and analyze the incidence of ketosis in dairy cows in an intensive farm in Yunnan province,the changes and differences of blood indexes and livers of perinatal ketosis dairy cows and healthy dairy cows were compared and analyzed,for providing theoretical basis in the prevention and control of ketosis dairy cows and veterinary clinical diagnosis and treatment.Forty Holstein cows with 2 to 4 parities were randomy selected in this study.Blood samples were collected 5 days before delivery,on the day of delivery,5 days and 10 days after delivery.The cows were divided into healthy group and ketosis group according to the concentration ofβ-hydroxybutyric acid(BHBA).Cows in ketosis group that died or were eliminated due to ketosis were selected and liver tissues were taken for pathological sections.The results showed that the levels ofβ-hydroxybutyric acid(BHBA)and glucose(GLU)in ketosis group were significantly higher than those in healthy group(P<0.01),and significantly lower than those in healthy group(P<0.05).Free fatty acid(NEFA)and aspartate transferase(AST)were significantly increased on postpartum 10 d(P<0.01),triglyceride(TG)was significantly increased on postpartum 10 d(P<0.05),and paraoxonase(PON-1)was significantly decreased on postpartum 10 d(P<0.05).Pathological sections of liver showed that compared with healthy cows,the overall structure of liver in ketosis cows was abnormal,liver cells had steatosis,and lipid droplets of different sizes appeared in cytoplasm,and fat accumulation was serious.The results showed that the incidence of ketosis was 47.5%,which occurred 10 days after delivery.Liver function indexes were abnormal,liver fat accumulation was serious,pathological lesions were obvious,and there was a potential risk of being eliminated.