Seasonal Variations in the Corpuscles of Stannius in Notopterus notopterus (Pallas)

Abstract

Seasonal changes in the corpuscles of stannius of Notopterus notopterus (Pallas) have been studied during various stages of reproductive cycle. During the pre-spawning period, corpuscles of stannius are found as enlarged, oval or elongated in shape, lobes are clear and show cellular and nuclear hypertrophy while spawning phase shows atrophy in the corpuscles of stannius, their cells and nuclei. During post-spawning period corpuscles of stannius are more active than spawning phase and showed high physiological activity. Two corpuscles of stannius are also observed during this phase. This study shows that corpuscles of stannius are more active during late prespawning phase. During such period, animals are sexually mature and an increased estrogen secretion by the ovaries is naturally expected. This study suggests a correlation with the gonadal maturation and structural changes in the corpuscles of stannius during seasonal variations. © 1991, Editorial Board of Okajimas Folia Anatomica Japonica. All rights reserved.