Reducing dietary protein concentrations and replacing fish meal with porcine meat and bone meal do not affect growth or feed conversion of pond‐raised fingerling channel catfish, Ictalurus punctatus

Abstract

AbstractThis study evaluated dietary protein concentrations and replacing fish meal with porcine meat and bone meal (PMB) for pond‐raised fingerling channel catfish, Ictalurus punctatus. Three diets were formulated to have 28, 32, or 35% protein using soybean meal, cottonseed meal, and fish meal as the main protein sources, respectively. A fourth diet contained 32% protein with fish meal being replaced with PMB. Analyzed protein concentrations were 29.7, 31.9, 34.4, and 31.1% on 90% dry matter basis, respectively. Small fingerlings (average initial weight: 2.0 g/fish) were stocked in 20 earthen ponds (0.04 ha) at 172,970 fish/ha and were fed once daily to apparent satiation for 98 days. There were no significant differences in total diet fed, gross yield, final weight, feed conversion ratio, survival, or condition factor among diets. There were also no significant differences in ammonia‐N, nitrite‐N, chlorophyll a, or desirable zooplankton concentrations in pond water of fish receiving different diets. Results show that a diet containing about 30% protein can support optimum growth of pond‐raised channel catfish fingerlings of 2 g and larger in fertilized ponds fed once daily to apparent satiation. PMB can completely replace fish meal in a 32% protein diet. Economic analysis suggests considerable cost savings by replacing fish meal with PMB and reducing protein concentrations in channel catfish fingerling diets.