Effect of restricted feeding regimens on compensatory weight gain and body tissue changes in channel catfish Ictalurus punctatus in ponds

Abstract

Year 2 channel catfish averaging 41 g were stocked in 0.04 ha earthen ponds at the rate of 13 750 fish ha −1. When daytime water temperature reached 25 °C, one group of fish (four ponds per group) was placed on restricted feeding for 3 weeks during which time the fish were fed once every 3 days, another group was on restricted feeding for 6 weeks, another group was on restricted feeding for 9 weeks, and another group (control) was on full feeding continuously for the 18 week feeding period. All fish were fed as much as they would consume when placed on full feeding. After 18 weeks, the fish on restricted feeding for 3 weeks weighed approximately the same as the control, in fact, they required only 3 weeks on full feeding to catch up with the control. Fish on restricted feeding for 6 and 9 weeks weighed less ( P < 0.05) than the control at the end of the experiment; however, their gains were 90% and 86%, respectively, as much as the control. Feed conversion for the 18 week period was the same for all treatments. Dressing yield and body composition (total fat, protein, moisture) were the same for all treatments at the end of the trial. Immediately following the period of feed deprivation, body fat in all restricted fed fish was lower than in the control fish but within 3 weeks on full-feeding body fat in these fish increased to levels equal to those of the control fish. Muscle fiber diameter was not different among treatments at any period. These results indicate that Year 2 channel catfish in production ponds can partially or completely recover in weight gain and body composition from periods of limited feeding provided they are subsequently fed to satiety.