Title: Ammonia excretion and oxygen consumption rates of juvenile pompano on six experimental poultry by-product diets Authors
|Bradley, Seth -|
|Malone, Ron -|
Submitted to: Book of Abstracts Aquaculture America
Publication Type: Abstract Only
Publication Acceptance Date: October 30, 2008
Publication Date: March 15, 2009
Citation: Bradley, S., Pfeiffer, T.J., Malone, R., Riche, M.A. 2009. Ammonia excretion and oxygen consumption rates of juvenile pompano on six experimental poultry by-product diets [abstract]. Book of Abstracts Aquaculture America. p.36. Technical Abstract: Florida pompano is a high market value marine finfish and recirculating aquaculture systems provide a sustainable culture method for growing these fish at high production densities in inland where agricultural land is more affordable. To reduce the feed load burden on the operating costs of the RAS units five different poultry by-product meal feed ingredients where evaluated as replacement to fish meal in the pelleted feed diet. Evaluation of the fish meal replacement products consisted of determining 24-hour ammonia excretion and oxygen consumption rates for the juvenile pompano on these diets. Eighteen experimental systems with temperature control, biofiltration, UV sterilization, and supplemental aeration and oxygenation for 137 L tanks were utilized. Each tank was stocked with 75 juvenile pompano weighing approximately 10.0 g (+/-0.78 g) each and maintained on a 2.0 mm, 50-15 (crude protein to lipid) slow sinking finfish starter diet for two weeks before experimental feeds were provided. The fish were feed twice daily and three randomly chosen units were fed one experimental diet for 5 days before the fish in the selected units were evaluated over a 24-hour period for ammonia excretion and oxygen consumption. Every four hours the water flow and aeration in the three selected units were shut down. Dissolved oxygen and ammonia concentration was measured at the start of the shut down period and thirty minutes later, the end of the shut down period. At the end of the 24-h period, the pompano in each of the three experimental units were removed, weighed and counted. Oxygen consumption rates ranged from 14.1 g O2 per day per kg fish to 21.1 g O2 per day per kg fish with the standard fish meal diet having the highest daily O2 consumption rate and the standard poultry by-product diet having the lowest daily O2 consumption rate. The daily ammonia excretion rate ranges from 0.501 g TAN per kg fish to 0.943 g TAN per kg fish with the chicken by-product meal that was 70% protein and 10% fat have the highest TAN excretion rate and chicken concentrate that was 70% protein had the lowest TAN excretion rate. The fish meal diet had a daily TAN excretion rate of 0.624 g TAN per kg fish. The data obtained in useful in recirculating system design criteria and additional studies are planned for larger size pompano juveniles.