Final oocyte maturation (FOM) model and artificial reproduction of burbot spawners (Lota lota) originating from the F1 generation of a cultured stock in comparison to wild stock

Abstract The burbot (Lota L.) is one of the most promising freshwater new fish species for cold-water aquaculture. Due to the lack of availability of wild spawners, it is imperative to breed cultured spawners. In the present study, artificial reproduction of a cultured stock of burbot was carried out and then compared with wild fish reproduction results. Patterns of burbot final oocyte maturation were developed and they were compared during artificial reproduction of wild and cultured burbot. For the first time, a model of final oocyte maturation (FOM) was formulated in a hormonally stimulated female burbot. The relationship between the oocyte maturity stage is straightforward and, at a water temperature of 2 °C, progress by the next stage was observed in two-day intervals. This model was tested on a group of wild and cultured fish (generation F1) originating from the Vistula Lagoon (Northern Poland). In both cases, the very high utility of the proposed model in the artificial reproduction of burbot was confirmed. The fertilization was very high. In wild and cultured forms was similar and was over 95% (95.4 ± 0.3 and 95.3 ± 0.3 as mean ± SD for wild and cultured, respectively). The differences in the survival to eyed-egg-stage (92.2 ± 0.8 and 91.9 ± 0.7 for wild and cultured, respectively) and hatchability of eggs (91.1 ± 0.9 and 90.9 ± 0.8 for wild and cultured, respectively) were statistically insignificant. In summary, a cultured stock of burbot spawners can be successfully used for the stable production of the stocking material of this species.