Submitted to: Aquaculture America Conference
Publication Type: Abstract Only
Publication Acceptance Date: 11/16/2010
Publication Date: 3/1/2011
Citation: Ott, B.D., Torrans, E.L. 2011. Effect of Channel Catfish Ictalurus Punctatus Egg Mass Loading Rate on Performance of the “See-Saw” Incubator. Aquaculture America Conference. P. 150.
Interpretive Summary: NONE
Technical Abstract: The “See-Saw” is a vertical-lift incubator that increases water circulation around and through channel catfish egg masses. Baskets in the incubator move up and down on racks in conventional hatchery troughs, raising the rack in one trough while lowering the rack in the adjacent trough. Egg masses are placed inside the baskets and moved through the water column of the troughs. We measured the effect of loading density in See-Saw incubators on survival to hatch and swim-up. We loaded See-Saws (n= 5 for each treatment) with 15.0 ± 0.1 lbs (220,300 eggs), 30.1 ± 0.1 lbs (447,000 eggs), 45.1 ± 0.1 lbs (669,600 eggs), and 60.1 ± 0.0 lbs (893,100 eggs) of spawns. Water flow into the troughs was the same for each treatment and averaged 2.1 gal/min, roughly half of the recommended rate for commercial hatcheries. Survival to hatch averaged 81.0% overall but was lowest in the 60 lb treatment (73.3%). The average number of swim-up fry produced increased with higher stocking density, with the 15, 30, and 45 lb troughs producing 132,700, 263,800, and 429,400, respectively (Figure 1). However, the 60 lb treatment only produced 417,200 swim-up fry. Survival to swim-up in the 15, 30, and 45 lb treatments averaged 60 ± 9%, 59 ± 6%, and 64 ± 4%, respectively, similar to values reported in commercial hatcheries (60%), but survival in the 60 lb treatment was only 46 ± 8%. Hatchery space and water use would be maximized with See-Saw incubators loaded at the 45 lb rate. The See-Saw incubator loaded with 45 lbs per trough results in a similar hatch rate and survival to swim-up while incubating approximately 300% more eggs and using half the water in traditional paddle-type incubators.