The pituitary extract is probably the most used hormonal inducer to spawning and spermiation in fish culture. The possibility of a new income source for the fish farmer was the reason of this study. The aim of the present study was to verify the yield of the pituitary in silver catfish (Rhamdia quelen) as a function of weight and to analyze the economical viability of its extraction. Specimens (n=116) with 158-1543g were sacrificed for pituitary extraction. The gonadosomatic index (GSI) was also calculated to verify its relationship with the pituitary weight. The pituitary showed a significant relationship with silver catfish weight, but not with the GSI. The extraction of the pituitary is another profitable option to silver catfish productive market.
hypophysis; pituitary extract; fish culture income
