Channel Catfish Hatchery Production Efficiency Using a Vertical-Lift Incubator (the See-Saw) at Various Egg Loading Rates

Abstract Channel Catfish Ictalurus punctatus spawns are typically incubated in 0.25-in-mesh baskets suspended in water that is agitated with paddles positioned between the baskets. We previously tested a vertical-lift incubator (the “See-Saw”) using Channel Catfish spawns. When loaded with spawns at rates higher than recommended for traditional paddle-type incubators, as often occurs during the peak of the spawning season, survival to the swim-up stage was significantly (2.3 times) higher with the See-Saw than with traditional incubators. This project examined the effect of spawn loading rate and added oxygen on fry production with the See-Saw. In study 1, See-Saws were loaded with 15.0 ± 0.1 lb (mean ± SE; 219,825 eggs), 30.1 ± 0.1 lb (446,055 eggs), 45.1 ± 0.1 lb (668,206 eggs), or 60.1 ± 0.1 lb (891,157 eggs) of spawns per trough. Water flow averaged 2.1 gal/min—roughly 40% of the rate recommended for paddle-type incubators. Swim-up fry production increased in proportion to egg loading density up to 45...