Seasonal variations in the cyanophils of the pituitary gland in correlation with reproductive cycle of Channa striatus (Bloch).

Seasonal changes in the cyanophils of the proximal pars distalis of the pituitary gland of C. striatus are conspicuous, and they closely follow the reproductive cycle. There is a poor concentration of their glycoproteinaceous contents during the resting phase and higher concentration during the maturation phase. The cyanophils also undergo a process of hypertrophy, granulation, followed by degranulation and vacuolisation during the spawning phase. They almost empty their contents during the post-spawning period.