Parenteral Administration of Aureomycin to Young Calves with a Note on Mode of Action

Abstract
Weekly intramusc. injn. of 400 mg. Aureomycin as an AlCl3 complex in sesame oil to young calves increased growth by 30% over controls at 16 wks. Aureomycin administered orally at a level of 50-90 mg. daily stimulated growth by 20%. A study of rumen contents (flora and environment) of control calves, Aureomycin-injd. calves, and those fed Aureomycin orally was made. No significant differences were found in rumen pH, Eh, degree of fiber digestion in the artificial rumen, rumen flora, and B vit. content (B12, pantothenic acid, riboflavin, niacin, biotin, pyridoxine, thiamine, and folic acid) of the rumen fluid. Carcass studies reflected the larger size and wt. of the Aureomycin groups. Meat yields showed larger muscular and skeletal size. Data on increase in height at withers, bone size, and wt., suggests that bone metabolism may be the area in which Aureomycin exerts its effect.