Effects of producing stocking material of vendace Coregonus albula (L.), using spawners reared in captivity — initial studies

The aim of the studies was to conduct vendace, Coregonus albula (L.), spawning with spawners reared under controlled conditions. The initial work of rearing spawners was begun in spring 2006, and in the fall 2007 the brood stock numbered 26 females and 20 males. Overall, 155 g of spawn, which was about 71,500 eggs, was obtained. The mean effective fecundity was determined as 83,954 eggs kg^-1 of female body weight. The eggs obtained were incubated, and the hatchlings were reared for 7 weeks. In the third week, the mean larval body weight was 32 ± 9 mg, while in the fifth week the mean weight and length of the larvae was 50 ± 20 mg and 19.9 ± 3.27 mm, respectively. After 7 weeks of rearing, 14,162 juveniles of a mean weight of 109.3 ± 33.0 mg and mean length of 26.1 ± 3.15 mm were obtained. The cumulative mortality from fertilization to the fry stage was approximately 80.3%.