Impact of diet, dissolved oxygen concentration, and stocking density on channel catfish (Ictalurus punctatus) production performance

Abstract

Diet selection, stocking density, and target levels for dissolved oxygen concentration are three of the major management decisions made by aquaculture producers. These factors and their combinations were tested in channel catfish (Ictalurus punctatus) to determine their relative impact on food conversion ratio (FCR), growth performance, and proximate analyses after 8, 16, and 22 weeks of feeding to satiation in indoor tanks at 26.7°C and processing traits after 22 weeks. At the end of the study, catfish grew from 29 to 732 g with an FCR of 1.1 in the best performing treatment combination (high protein, high dissolved oxygen concentration, low density) and from 29 to 414 g with an FCR of 1.2 in the worst performing treatment combination (low protein, low dissolved oxygen concentration, low density). After each sample period, the high protein diet significantly decreased FCR and growth, stocking density had no impact on any recorded variable, and low dissolved oxygen concentration reduced appetite but also decreased FCR. As fish grew, FCR increased and feed consumption as a proportion of body mass decreased. All factors tested had little impact on proximate analyses, but the high protein diet consistently had worse protein conversion efficiency (PCE). Higher feed protein decreased both headed-gutted and fillet yield, but no other factor had an effect. In channel catfish, higher feed protein improves growth, FCR, and meat yield; higher dissolved oxygen concentration increases appetite; and stocking density has no impact on performance if oxygen is maintained at saturation.