Submitted to: Aquaculture America Conference
Publication Type: Abstract Only
Publication Acceptance Date: 11/23/2009
Publication Date: 3/3/2010
Citation: Ott, B.D., Torrans, E.L. 2010. The “See-Saw”: A Vertical-Lift Incubator Designed for Channel Catfish Ictalurus punctatus Egg Masses (abstract). In: Proceedings, Aquaculture America Conference, March 1-5, 2010. p. 445 Interpretive Summary:
Technical Abstract: Channel catfish (Ictalurus punctatus) egg masses are typically incubated in baskets that are suspended within metal troughs with water that is agitated and pushed around the eggs with paddles. A limiting factor in the successful incubation of channel catfish eggs is the absorption of oxygen to the developing embryos; sub-optimal levels of dissolved oxygen in the water results in premature hatching and increased deformities and mortality of developing catfish eggs. We designed and tested the ability of a new vertical-lift incubator (the “See-Saw”) to incubate channel catfish egg masses. Angle-aluminum racks were placed inside paired adjacent hatchery troughs with three hinged-lid baskets positioned in each rack. The racks were connected to overhead bars that moved up and down at six cycles per minute, raising the rack in one trough while lowering the rack in the adjacent trough. Egg masses were placed inside the baskets and moved up and down through the water column of the trough while the racks moved through the cycle. Both the See-Saw and control troughs were loaded with 25.6 ± 0.5 egg masses per trough which is 2.0 - 1.5x higher than recommended loading rates. Survival to swim-up stage was significantly higher (2.3-fold) in the See-Saw than the traditional control troughs. Many of the sac-fry produced in the control troughs were either dead when removed or died prior to reaching swim-up stage, presumably due to oxygen stress. Use of the See-Saw hatchery may enable hatchery operators to increase their fish survival while simultaneously using proportionately less water and space in their facility.