Embryotoxic and long-term effects of cadmium exposure during embryogenesis in rats

The present study was performed to evaluate the long-term behavioral effect in offspring of a subteratogenic Cd dose administered by the oral route to Wistar rat during organogenesis. First, the teratogenic Cd dose was determined by treating pregnant rats with 20 mg/kg Cd from Day 6 to Day 14 of pregnancy and by visceral and skeletal analysis of their fetuses. In a second experiment, pregnant rats treated with this Cd dose were allowed to give birth and nurture their offspring. The physical and behavioral parameters of the offspring were analyzed in infancy and during adulthood. Results showed that Cd treatment during organogenesis (1) was not able to induce maternal toxicity; (2) induced external malformations; (3) increased significantly fetus anomalies and malformations, with reduced metacarpus ossification, cleft palate and right or left renal cavitation being observed in these animals; (4) did not modify pup body weight or weight gain during the lactation period; (5) improved testis descent and delayed the vaginal opening of pups; (6) did not modify ear unfolding, incisor eruption, eye opening, negative geotaxis or palmar grasp; (7) did not modify the open-field parameters and the stereotyped behavior of male or female pups; and (8) modified male sexual behavior and (9) reduced female sexual behavior. We conclude that prenatal exposure to a teratogenic Cd dose induced in the survivor animals several deleterious effects in their development as well as in adult behaviors, mainly in the sexual sphere.