Visual and chemical stimuli from live prey affect feed intake, weight gain, and growth of juvenile Florida pompano (Trachinotus carolinus)

This study investigated the influence of visual and chemical stimuli from live prey on juvenile Florida pompano (Trachinotus carolinus) growth. Twelve tanks within four independent recirculating systems housed fish of similar weight (obtained from a commercial fish farm) in groups of ten. Prior to their morning feeding (they were fed twice daily at 10 h and 16 h with commercial pellets), fish were exposed to one of four stimuli: visual and chemical cues from Artemia, mole crab, feed pellets (control for stimuli), or seawater (control for procedures). Key growth parameters were monitored weekly for seven weeks, including feed intake, weight gain, and specific growth rate (SGR). Fish exposed to Artemia and mole crab stimuli exhibited significantly higher feed intake (23.11 +/- 1.37 and 23.45 +/- 1.38 g/fish), weight gain (169.28 +/- 7.59 and 172.75 +/- 12.57%), and SGR (2.02 +/- 0.05 and 2.04 +/- 0.09% day(-1)) compared to those exposed to feed pellets (stimuli control) and seawater (procedures control): feed intake (20.81 +/- 0.684 and 19.30 +/- 0.39 g/fish), weight gain (136.25 +/- 4.51 and 140.23 +/- 6.36%), and SGR (1.75 +/- 0.03 and 1.78 +/- 0.05%.day(-1)). These findings highlight the importance of visual and chemical cues from live prey as feeding incitants and stimulants. By enhancing feeding motivation and intake, these stimuli promote growth and potentially improve the welfare of juvenile Florida pompano.