Photo-thermal induction of gonadal maturation in completely controlled conditions is still not well explored in pikeperch. Thus, wintering intensively reared breeders in outdoor pond conditions might be rather suitable alternative to use these fish for larvae production. In this study, we compared the propagation success of indoor-reared [recirculating aquaculture systems (RAS)-reared fish, RRF] and wild (WCF) pikeperch females wintering them in outside earthen ponds. Each group was composed of six females and four males which were artificially propagated following hormonal induction with human chorionic gonadotropin. Beside the main parameters of reproductive success, fatty acid composition of dry eggs and mortality during early larviculture were assessed. The only statistically significant difference among reproductive parameters was found in latency time, which was significantly lower in RRF. Fatty acid profiles of dry eggs were rather similar between the groups; however, significant difference was noticed in phospholipid fraction in EPA/AA (eicosapentaenoic acid; C20:5n-3/arachidonic acid; C20:4n-6) ratio which was, on average, five times higher in the RRF (5.1 AE 3.8) than in WCF (0.9 AE 0.3). Significantly lower mortality was seen in the larvae originating from wild breeders (13.4 AE 1.7% and 27.0 AE 4.9% for WCF and RRF respectively). Wintering indoor-reared females in outdoor pond conditions led to appropriate gonadal maturation, and ovulation occurred in all examined females. The lower quality of larvae was likely caused by suboptimal broodstock nutrition, which should be studied further, with special consideration given to the EPA/AA ratio and the phospholipid content and composition of the diet.

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Major problem faced by aquaculture industry is the need to obtain a balance between rapid fish growth and optimum use of feed. Since the feed cost accounts ~60% of the total farm production costs (Tan & Dominy, 1997), the economic viability of the culture operation depends on the feed. The global aquaculture feed industries are heavily dependent on fishmeal protein because of its balanced amino acid and fatty acid composition and palatability. However, limited supply and high price of fish meal together stimulated several studies to substitute fish meal partially or completely with alternative protein sources (Fournier, Huelvan, & Desbruyeres, 2004;