Reproduction of pikeperch (Sander lucioperca Linnaeus, 1758): Artificial spawning ground techniques and embryo monitoring

Abstract

Our present work was carried out on reproduction techniques of the pikeperch on artificial spawning grounds with the main objective to improve the embryonic and larval development. The experimentation was performed at the level of the aquaculture farm of Ain Sultane (Ain Defla, Algeria) over the spring 2021. We have chosen the pike-perch spawners from a dam that allows them to reproduce easily in this biotope where they find a lot of forage fish (cyprinids) available for the larvae. The spawning grounds were launched before the pikeperch breeding season to ensure that the target species can use the artificial substrates to lay their eggs. The total number of spawning grounds designed were 19 of 1 m2. Feeding of the larvae started with egg yolk (vitellus) and Saccharomyces cerevisiae (yeast) for 3 days, after that, the larvae were fed with small zooplankton (rotifers). The distribution of the food was gradually increased with the administration of cladocerans (bosmina) and copepods until the end of the larval phase. The results obtained showed that the egg densities collected on these spawning grounds were quite high. An average of 24,2000 eggs was counted per spawning ground with 193,600 fertilized eggs, thus a very high fertilization rate of pikeperch of 80%. The incubation of the eggs lasted 8 days at a temperature of 18°C which fluctuated between day and night and which delayed the embryogenesis and the hatching. We observed a mortality rate evaluated at 20% due in particular to an overloading of the breeding tanks which provoked cannibalism due to the genetic predisposition of this carnivorous fish. Our larval monitoring was not regular (distance from the farm) which intensified cannibalism and consequently mortality. We can conclude from these results and considering the difficult experimental conditions that we were able to create conditions similar to natural conditions for the reproduction of pikeperch.