Antibiotics for the Prevention of Bloat in Cattle Grazing Ladino Clover

Abstract

The oral administration of chlortetracycline, oxytetracycline, bacitracin, streptomycin and penicillin for the prevention of bloat in steers grazing Ladino clover has been investigated. Penicillin was the only antibiotic studied that prevented bloat when a single dose of 300 mg. or less was given. Single doses of 25 mg. of procaine penicillin gave good protection from bloat in yearling steers. Fifty mg. of procaine penicillin protected yearling steers in every case for 1.5- to 3-day periods. Older steers, weighing about 900 lb. required 50 to 75 mg. of procaine penicillin to prevent them from bloating. Clover consumption appeared to be slightly higher after penicillin treatment than before. Potassium penicillin, in equivalent amounts, was equally as effective as procaine penicillin for the prevention of bloat. The nature of the procaine penicillin carrier and the concentration of the penicillin in the carrier appeared to have no effect. Penicillin had to be given several hours or overnight before it was effective in preventing bloat in steers that were bloating before treatment.