A STUDY ON THE CORRELATION BETWEEN THE STRUCTURE OF THE PITUITARY GLAND OF THE INDIAN CATFISH HETEROPNEUSTES AND THE SEASONAL CHANGES IN THE OVARY

Abstract

Indian carps which are extensively cultivated in ponds for food do not spawn in confined waters. Various environmental factors like dissolved oxygen content, monsoon showers, pH, temperature and the availability of suitable spawning grounds are considered a sine qua non for successful spawning (Hora [1945]; Mookerjee [1945]; Khan [1945]; Husain [1945]). It has been experimentally demonstrated that environmental factors are not directly responsible, either collectively or individually, in making the breeders spawn (Husain [1945]; Ganapathi and Alikunhi [1949])