Toxicity, fertility, teratogenicity, and dominant lethal tests in rats administered cadmium subchronically: II. Fertility, teratogenicity, and dominant lethal tests

Abstract

Four groups of Sprague-Dawley rats, each of which consisted of 14 males and 14 females, were administered 0, 0.1, 1.0, and 10.0 mg/kg/day of cadmium (Cd) for 6 weeks. Males and females within each group were mated 6 days a week for 3 weeks, changing partners every week if necessary. Cd was administered during the mating period. Pregnant females were administered Cd during the gestation period and killed on the 20th day of gestation for teratogenicity tests. Males were mated with 2 virgin females per male per week for 6 weeks. Pregnant females were killed on the 13th day of gestation for dominant lethal tests. Numbers of total implants and live fetuses in the 1.0 mg/kg group decreased slightly, but there was no significant difference from the control. Numbers of total implantations and live fetuses decreased significantly in the 10.0 mg/kg group. In this group, the number of resorbed fetuses increased significantly and the number of corpora lutea decreased without showing a significant difference from the control. Fetuses from the 10.0 mg/kg group showed decreased body weight, body length, and tail length and increased placental weight. About one-third of fetuses were subjected to visceral examination, but no specific anomalies considered to be due to Cd toxicity were found. Skeletal examination was performed for the remaining two-thirds of the fetuses. Delayed ossification of the sternebrae and caudal vertebrae was observed. No dominant lethality was found under the conditions used here. Although physiological deterioration caused by 10.0 mg/kg of Cd has an adverse effect on mating performance, mating ratio, the number of total implants, the number of live fetuses, and the ossification of fetuses, Cd induced neither teratogenicity nor dominant lethality.