Post-graduate Department of Zoology, RTM Nagpur University, Nagpur -4400 33 (Maharashtra), INDIA *Corresponding author. E-mail: veena_dongre@yahoo.com Received:July 20, 2011; Revised received: March 12, 2012; Accepted: August 14, 2012 Abstract: Prostaglandins are a class of fatty acids which are "traditionally" associated with a variety of autocrine and paracrine functions in the vertebrate body. In many fishes, however, F prostaglandins also function as a hormone that stimulates sexual behavior. In the present study, F prostaglandin was used to assess the efficacy on reproductive behavior and spawning in relation to pituitary gonadal axis in the fish, Cyprinus carpio by administering different doses. Early maturity was observed in fish leading to courtship and spawning. The histological study of olfactory lobe, pituitary gland and gonads showed that the prostaglandin is also functioning as potent olfactory stimulants with sex pheromonal activity of the fish. F prostaglandin was metabolized and released into the water where it functions as a sex pheromone, stimulating male and female sexual behavior resulting into spawning. It was concluded that F prostaglandin acts as an inducer for successful breeding in the fish, C. carpio.