HISTOLOGICAL ,HISTOCHEMICAL, ENZYME-HISTOCHEMICAL AND ULTRASTRUCTURAL OBSERVATIONS ON THE GONADS OF ONCOMBLANIA SNAIL IN DIFFERENT LATITUDE REGIONS IN CHINA / 中国血吸虫病防治杂志

ABSTRACT

Our field experiments have proven that when Oncomelania snails have been fed in north-ward 33?15' north latitude regions the growth of their gonads would be inhibited and they would have lower reproductive rates. In order to further evaluate the mechanism, the gonads of Oncomelania snails fed in Jining, Shandong Province (35?23' north latitude), Xuzhou, Jiangsu Province (34?21' north latitude) and Zhengjiang,Jiangsu Province (32?10' north lati-tude ,control group) were observed in histology, histochemistry,enzyme-histochemistry and ultrastructure. The results showed the testes and the ovary of Oncomelania snails fed in Jin-ing and Xuzhou were atrophied ;the contents of glycogen,DNA and histone and the activities of cytochrome oxidase (CCO) ,5'-Nucleotidase(5'-NT) ,LDH and G-6-Pase were inhibited in the testes and ovary of these snails. But the SDH activity was elevated in the testes. The ultrastructural observation showed the number of sperm had reduced, the sperms were dena-tured in vary degrees in testes of the snail in Jining and Xuzhou.