REDUCED FREQUENCY FEEDING REGIMES IN SUNSHINE HYBRID STRIPED BASS (FEMALE Morone chrysops × MALE M. saxatilis)

Different feeding strategies were conducted in an attempt to improve the feed conversion ratio (FCR) of hybrid striped bass (Morone chrysops x M. saxatilis, HSB) while maintaining good growth and reducing the feeding frequency under optimal water quality and temperature conditions. The HSB (initial weight 416 + 7.9 g, mean + standard deviation) were fed for 88 days under two different feeding methods (automated belt feeding and ad libidum hand feeding) and two different frequencies (3 days and 5 days per week). High protein level floating pellets were used during the experiment (45% protein, 16% fat, Zeigler Brothers, Inc.). Each experimental group was replicated three times in flow-through, outdoor tanks (N = 150 fish each tank). At the end of the trials the fish were weighed and the FCR was calculated for each group. There were significant differences in mean total weight fed per fish, initial feeding rate (percent body weight), and final feeding rate by one-way analysis of variance (ANOVA) and Tukey-Kramer Honestly Significant Difference post hoc test (P < 0.05) (Table 1). There were no statistical differences in average initial weight, final weight, daily weight gain, or FCR between the treatment groups. Differences were not detected in the FCR between the different groups, however the means of the tank replicates were quite variable ranging from 1.71-2.49. The mean FCR was approximately 20% higher in fish that were fed more frequently (5 days per week) compared to those that were fed less frequently (3 days per week). Although not statistically significant, this increase in FCR may have an economic impact in commercial operations. Hence, reducing the frequency of feeding may improve the FCR of sunshine bass and lower the overall cost of feeds required to raise the fish, especially as they get larger during Phase III (final growout) production.