Use of shrimp Penaeus spp. to replace krill Euphausia spp. in a feed training diet for largemouth bass

摘要

Fingerlings of largemouth bass Micropterus salmoides with an initial weight of 1.0 g were trained to accept a pelleted ration by means of feeding regimes involving various combinations of freeze-dried krill, krill meal, dried shrimp, and dried shrimp meal. Either dried krill or dried shrimp was fed for the first 3 d. Pelleted feeds containing krill or shrimp meal and a commercial ration were fed throughout the remainder of the feed training period. Fish were fed over a 10-d period to determine training success, weight gain, feed conversion ratio, and survival, All feeding regimes had similar survival, with the percentage of nonfeeders among the survivors ranging from 2.30 +/- 1.1% to 3.48 +/- 1.1 % (mean +/- SD). Fish trained with krill had a greater average weight at harvest (1.63 +/- 0.1 g) than those given shrimp meal (1.38 +/- 0.1 g). The cost of feed per 1,000 fish trained was greatest with the freeze-dried krill and krill meal (US$16.75) and least with dried shrimp and shrimp meal ($1.25). The weaker feeding response to dried shrimp favors the use of krill to start training, The lower cost of shrimp meal and the improved pellet stability, together with the fact that it elicits a feeding response similar to that of krill meal, make it a suitable ingredient for the pellet training phase.