BIOCHEMICAL EVALUATION OF DOWNER DAIRY COWS WITH FATTY LIVER AND ESTIMATE PROGNOSIS OF SURVIVAL RATE IN IRAN

This study evaluated the relationship between severity of fatty liver and macromineral status in downer dairy cows with fatty liver and determined the usefulness of selected liver biochemical analyses for assessing prognosis. Blood samples were collected from 30 Holstein downer cows that could not rise 24 hours after recumbency and after first treatments. Serum activity of muscle and liver-derived enzymes and concentration of non-esterified fatty acids (NEFA), cholesterol and macrominerals (Ca, Mg, K, Na, P) were determined. Serum concentration of NEFA and cholesterol, and NEFA/cholesterol ratio are good indicators of fatty liver. In this group of 30 downer cows, 70% had calved within first week and 30% calved within first 100 days of sampling. In this study about 70% of dairy cows had biochemical evidence from some degree of fatty liver that 20% were with mild and 50% were with moderate fatty liver and 80%from they were in the 1st week after calving. The 50% downer cows were with moderate fatty liver that all of them culled and had significantly higher NEFA/cholesterol ratio. The NEFA/cholesterol ratios herein were about 2 times higher in cows with moderate fatty liver compared with the reference cows. The prognosis is guarded for downer cows with moderate fatty liver.