Chlortetracycline in the Nutrition of Guinea Pigs. ∗ †

Abstract

Summary

Chlortetracycline hydrochloride has been included in various diets of a guinea pig colony for 3 years without evidence of toxicity. It had no effect on growth rate and caused no mortality when added to a purified diet at levels from 25 to 200 mg/kg. At the routine level of 25 mg/kg, the antibiotic decreased abortions and adult mortality and eliminated cervical lymphadenitis from the breeding colony. Although chlortetracycline may be toxic to guinea pigs under some conditions, in our laboratory it has been beneficial in the maintenance of a breeding colony and has been used routinely in purified experimental diets for growth studies.