FEEDING REGIMES FOR LARGEMOUTH BASS AT HIGH SUMMER TEMPERATURES

Although many producers and agencies have been culturing largemouth bass (LMB; Micropterus salmoides) as a food fish for over two decades, limited data are available on optimal feed rates and feeding regimes for juvenile fish, particularly at high water temperatures. In order to address this concern, two experimental trials were carried out with LMB at the UAPB Lonoke Fish Health Services Laboratory. In the first trial, juvenile LMB (12.7 ± 0.2 g) were stocked into a recirculating system (2,725 L) with nine tanks (227 L each, 20 fish/tank). Water temperature was maintained at 30°C. Fish were fed a commercial feed (Skretting, 48% protein, 18% lipid) four times a day at 3, 5, or 7% total body weight for four weeks. Feed amounts were adjusted weekly following sampling from each treatment. Water quality remained within acceptable levels for LMB. LMB were significantly heavier at harvest at the highest feeding rate (Table 1). Trial 2 was conducted at the same water temperature but with smaller LMB (7.16 ± 0.07 g) that were either fed to satiation daily, every other day, or every third day in a nine tank (47 L each; 15 fish/tank) 1,000 L recirculating system (Table 2). Survival in both trials exceeded 97%. Initial and final fatty acid profiles of fish in the two trials are being analyzed and results will be presented. Improving feed management practices in these areas should improve water quality and feed utilization efficiency, while reducing cannibalism.