The effect of different diets on the growth and mortality of juvenile pikeperch (Sander lucioperca) in the transition from live food to formulated feed

The efficiencies of four feeding methods were compared in the transition period from live food to dry feed in pikeperch (Sander lucioperca). Pond-nursed fry were trained to artificial feed without a transition (Group P) and with a transition, using a combination of dry feed and different kinds of live food-Chironomus larvae (Group C), Tubifex (Group T) and Daphnia (Group D)-during a 12-day-long trial. The ratio of dry feed for the transition groups was increased from 0 to 100% in 3-day intervals. The highest specific growth rates and condition factors were detected for Group C (4.2%, 1.46 +/- 0.5) and Group T (4.2%, 1.48 +/- 0.6), respectively. The survival percentages of the groups were as follows: 86.7 +/- 9% (Group C), 78 +/- 4% (Group T), 52 +/- 1.4% (Group D) and 41 +/- 9% (Group P). The rate of cannibalism ranged between 6.3 and 13.7% during the transition period. Larger-sized fish seemed to learn more rapidly to accept dry feed than their smaller counterparts.