IMPAIRED SPECIFIC IMMUNOREACTIVITY IN COWS WITH HEPATIC LIPIDOSIS

In this study, hepatic lipidosis in cows was experimentally induced by offering an energy surplus during the dry period. Liver triacylglycer ol (TAG) was 16% in the experimental group. In the control group fed t he same diet in restricted quantities, liver TAG was about 7%. The ani mals of both groups were vaccinated with tetanus vaccine at Day 3 afte r parturition. It was demonstrated that the cows with high liver TAG p ercentages had lower humoral and cellular (P < 0.05) immunological res ponses compared with the animals with low liver TAG levels at Day 14 a fter vaccination. The results obtained in the high TAG group support t he notion that the frequent occurrence of aspecific infections in cows with hepatic lipidosis may be due to impaired immunoreactivity. (C) 1 997 Elsevier Science B.V.