Rat two-generation reproductive toxicity and teratogenicity studies of a novel coccidiostat – Ethanamizuril

Abstract In the current study, to support the safety assessment of ethanamizuril as a new potent anticoccidial agent of triazine compounds, a reproductive toxicity and teratogenic potential assay of ethanamizuril was investigated. Groups of 30 males and 30 females were administered 0, 0.02, 0.1 or 0.2 mg/ml ethanamizuril by gastric incubation through a 10-week prebreed period as well as during mating, gestation, parturition and lactation in any generation. Compared to the control group, no test compound-related changes in copulation index, fertility index, gestation length, litter size, pup weight, pup sex ratio, pup viability, epididymal sperm counts or motility or other functional reproductive measures were noted in any generation, except few significant changes in high dose group in the number of sperm motility at III level in F0 males and the body weights of GD14 and GD21 in F1 rats. There were no compound-related necropsy findings or effects on organ weight. Histopathologic examinations revealed no evidence of compound-related changes in any organs including the reproductive organs of both sexes. In conclusion, long-term administrated 0.2, 1.0 and 2.0 mg/kg of ethanamizuril by means of oral gavage did not affect the reproduction of Sprague-Dawley rats and the development ability of their offspring under the experimental conditions.