Effects of cadmium on somatic and gonadal growth of juvenile females of the estuarine crab Chasmagnathus granulata (Brachyura : Grapsidae)

Juvenile female crabs of Chasmagnathus granulata (Decapoda: Brachyura) were exposed to 0.1 and 0.5 mg/l of cadmium for at least 50 d before and 15 d a fter molting. The gonads were dissected and fixed for histopathological stu dies, while the carapaces were preserved to measure calcium content. A cadm ium concentration of 0.5 mg/l was lethal for juvenile crabs. The few surviv ing crabs at this concentration were unable to molt. Although most crabs ex posed to 0.1 mg/l of cadmium survived and molted, they presented a signific antly higher incidence of pathologies in the ovaries than did control crabs . These pathologies were hypertrophy and cariorhexis in primary oocytes, as well as reactional atresia in secondary oocytes. Although no significant d ifference in the proportion of crabs with mature ovaries after molting was noted between the control and cadmium-exposed animals, a trend towards slow er maturity was noticed due to the effect of cadmium.