Journal of Aquaculture Research & Development

Abstract

Effects of Dietary Supplements on Growth Performance and Phosphorus Waste Production of Australian Catfish, Tandanus Tandanus, Fed with Diets Containing Canola Meal as Fishmeal Replacement

Huy PV Huynh *,Dayanthi Nugegoda

Effects of dietary phytase, amino acid (AA), and inorganic phosphorus (P) in canola meal diets on the growth and P waste production of Australian catfish, Tandanus tandanus were evaluated. Fishmeal protein was replaced by 30% and 45% with canola meal protein in two separate experiments, in which test diets were fortified with phytase, AA, inorganic P, or their combinations. Addition of sole phytase to the 30% replacement diets did improve growth performance and feed utilization of fish compared to those fed with the non-phytase diet. Inclusion of phytase and/ or AAs did not improve the growth and feed utilization of catfish when fishmeal protein was replaced by 45% while adding inorganic P showed significant improvement in the performance of the fish. Ortho-P waste was significantly lower while total P waste was significantly higher in fish fed with canola meal diets at both levels of fishmeal replacement. Phytase did not affect the total P waste of catfish but a combination of phytase and AA resulted in a significant reduction. Dietary inclusion of inorganic P significantly elevated the total P waste of catfish compared to that of the control fish. It was concluded that the use of canola meal in combination with inorganic P in diets for Australian catfish could significantly increase nutrient pollution in aquaculture.