Effect of winter feeding rate, feed form and trigger temperature on yield and condition of golden shiners, Notemigonus crysoleucas.

摘要

Two trials were conducted at the Aquaculture Research Station, University of Arkansas from 1995 to 1997 to evaluate winter feeding strategies for small golden shiners, Notemigonus crysoleucas, destined for the crappie, Pomoxis spp. market. Fish werestocked at 615 g/pool (approximately 127 or 158 fish/m2, trials 1 and 2, respectively) in aerated, 5.9-m2 pools for 100 and 104 days, respectively. In the first trial, fish were fed a commercially available 32% crude protein crumbled, extruded pellet once daily at feeding rates of 0% (fertilizer only), 1%, or 2% of body weight/day (bw/d) on days when the afternoon air temperature was ?℃. Unfed fish lost weight and their condition declined. Fish fed at 1% maintained both weight and condition, while fish fed at 2% gained weight. Fish in the second trial were fed once daily at 1% bw/d on those days when the air temperature was either ?℃ or ?0℃, with either a commercially available crumbled, extruded pellet or a sinking pellet (compressed). Fish fedcrumbles were in significantly better condition at harvest than fish fed a sinking pellet, regardless of trigger feeding temperature, although average weight was not significantly different. Feeding on days with air temperatures ?℃ provided 13% more feeding days than a trigger temperature ?0℃, and fish grew more over the winter. Two condition indices, relative weight (Wr) and Fulton's condition factor (K), proved useful in evaluating the condition of golden shiners cultured using different feedingstrategies.