Effect of oral administration of 1,3-diphenylguanidine on sperm morphology and male fertility in mice.

An oral testicular toxicity and male fertility study was carried out in CD-1 mice with 1,3-diphenylguanidine (99.9% purity). 1,3-Diphenylguanidine was administered to male mice by daily gavage at dose levels of 0, 0.06, 0.25, 1, 4 and 16 mg/kg body wt. per day during an 8-week premating period. Females were not dosed at any time during the study. Sperm abnormality evaluation was performed in approximately half the males, randomly selected from the control and 16-mg/kg dose group on completion of dosing. The remaining males in the control, 4- and 16-mg/kg body wt per day groups were mated with non-dosed females. Reproductive performance, necropsy findings and litter data were recorded. No differences were found between control and dosed groups in body weight gain during the dosing period, macroscopic observations and organ weights at necropsy. Microscopic examination of the testes and determination of the frequency of total sperm abnormalities in the 16-mg/kg body wt per day group, did not show any effect due to 1,3-diphenylguanidine dosing when compared to the control group, except for a slight increase in sperm with folded tails but normal heads. Male and female fertility as well as reproduction performance were comparable in the groups examined (0, 4 and 16 mg/kg body wt per day). Maternal necropsy findings and litter data did not reveal any dose-related effect. It was concluded that under the conditions of the present study, 1,3-diphenylguanidine did not exert any significant adverse effects on fertility, reproductive capacity or embryonic/fetal development in CD-1 mice when administered to males at levels up to 16 mg/kg body wt per day.