Effects of different weaning strategies on survival and growth in Chinese longsnout catfish (Leiocassis longirostris Günther) larvae

The effects of different weaning strategies during the larval rearing of Chinese longsnout catfish were determined in two trials. In the first trial, the effect of abrupt-weaning from live prey (Artemia nauplii) to microdiet at 5, 6, 7, 8, 10 dph, respectively was investigated. The second trial examined the effect of weaning with co-feeding at different ages (6, 8 and 10 dph).The survival, growth, digestive enzymes, coefficient of variation of final body weight (CVFBW) and body length (CVBL), digestive enzyme activities, fish body lysozyme and fish body glucose were significantly influenced by abrupt-introducing of microdiet (P < 0.05). When weaning with live prey, only the fish body lysozyme significantly increased in the group introduced to microdiet on 8 and 10 dph (P < 0.05).The study showed that abrupt-weaning of Chinese longsnout catfish should be obtained after 10 dph. Co-feeding could reduce the stress to larvae and therefore the weaning could start at 6 dph with co-feeding.

► We investigated the activities of digestive enzymes at different weaning strategies.
► Abrupt-weaning of larvae should be obtained after 10 dph.
► Co-feeding with Artemia could reduce the stress to larvae and could start at 6 dph.