CLINICAL-EVALUATION OF IN-FEED ZINC BACITRACIN FOR THE CONTROL OF PORCINE INTESTINAL ADENOMATOSIS IN GROWING FATTENING PIGS/

This field trial was designed to investigate whether the incorporation of zinc bacitracin into pig feed would prevent porcine intestinal ade nomatosis. Two hundred-and-eighty-eight weaned pigs on a farm with a p revious history of the disease were divided into 16 pens of 18 pigs, T wo dietary regimens of zinc bacitracin were tested: from weaning up to 100 days of age, either 300 or 200 ppm zinc bacitracin were incorpora ted; from 100 to 125 days of age, either 200 or 100 ppm zinc bacitraci n were added; and from 125 to 156 days of age (slaughter), either 100 or 50 ppm zinc bacitracin were added, The results were compared with a positive control group which received 60, 60 and 30 ppm salinomycin d uring the same periods, and with a negative control group which receiv ed no antibacterial and/or performance enhancer, The mortality, diarrh oea scores, average daily weight gains, average daily feed intakes and feed conversion ratios of the pigs were assessed. At slaughter, sampl es of ileum were taken from eight randomly selected pigs per group for bacteriological and histopathological examinations, The three treated groups all performed better than the control group, and the group rec eiving the high dose regimen of zinc bacitracin performed significantl y better than the groups receiving the low dose of zinc bacitracin or salinomycin.