Use of Tilapia as Supplemental Forage for Channel Catfish Broodstock

Abstract

The purpose of this study was to determine the effects of supplemental feeding with forage fish on the spawning success and egg quality of channel catfish Ictalurus punctatus. Channel catfish broodstock were maintained for 2 years on a diet of either commercial catfish feed with 32% protein or commercial catfish feed and live blue tilapia. Fish fed forage fish had significantly larger eggs and a higher gonadosomatic index prior to the second spawning season. They also spawned larger eggs, had a higher hatch rate, and produced more and larger fry than fish fed only commercial feed. During the second year of the study, growth rates and food conversion ratios were better over the winter months for channel catfish fed supplemental forage but worse over the summer months compared with fish fed only commercial feed. Over the two spawning seasons, broodstock fed forage fish produced an average of 9,221 sac fry/kg of females stocked in the spawning ponds. The addition of 10–15 kg/ha of blue tilapia to channel catfish broodstock ponds in the summer appears to be a practical method of increasing spawning success and fry production.