[Reproduction study on netilmicin. (2) Fertility study in rats (author's transl)]

Fertility study on netilmicin (NTL), a new aminoglycoside antibiotic, was carried out in Sprague-Dawley rats (Slc : SD). NTL was administered intramuscularly to male rats at the daily dose of 12.5, 25, 50 and 100 mg/kg from 6 to 15 weeks of age for 9 weeks before mating and during the mating period, and to 10 weeks old female rats at the daily dose levels from day 14 before mating through day 7 after gestation. The increase of kidney weight at the dose of 12.5 mg/kg and more, the decreases of food intake and body weight were observed in treated male rats. The decreases of food intake and body weight were observed in female rats treated with the dose of 50 and 100 mg/kg. No dose-related changes were observed in mating and fertility ratios of parent animals, numbers of corpora lutea and implantations, fetal mortality, external, visceral and skeletal anomalies, body weight, body length and tail length of fetuses. Therefore, it can be concluded that maximum non-toxic dose level of NTL on rat fertility is 100 mg/kg.