The Effect of Aureomycin on Development of the Frog¹

This is the authors' abstract. We don't add key points for this paper.

Numerous investigators have shown that when minute quantities of aureomycin (chlortetracycline), terramycin (oxytetracycline ), penicillin o r streptomycin were fed together with the basal ration to chicks, swine, cows and other domestic animals they gained body weight ( JLIKES and WILLIAMS, 1933; STOKSTAD, 1951 and JUKES, 19.5).T h e growth-promoting effect of antibiotics is postulated to result from changes of intestinal microflora produced by the antibiotics (JUKES, 1933).T h e present experiment was planned t o determine the effect of an antibiotic on the growth of frog tadpoles during metamorphosis and t o consider the possible mechanism of the effect, .ifany. MATERIAL AND METHODS Ninety tadpoles of Rnnn catcsbeiatzcz.raised from eggs obtained from a single pituitary-injected female, were divided into three groups a t the metamorphic stages IV and V ( T A Y m R and KOLLHOS.1946).T h e first group of tadpoles was fed with control food consisting of 63",, of wheat flour, 33",, of whole duck's egg and ?",, of d r y yeast powder.T h e second and third groups were fed the same food containing 10 g. and 1 g. of aureornycin (Lederle) per 10 kg. of control food respectively.In addition, to each 10 kg. of the two kinds of aureomycin food 1 mg. of vitamin B1? (Lederle) was added in order to obtain the maximal growth effect.This was done because the first preparation of antibiotics used widely in animal feeds contained aureomycin and vitamin BIZ.It was thought then there was some interrelationship between the antibiotic and vitamin B1?