Seasonal simulated photoperiods influence melatonin release and immune markers of pike perch Sander lucioperca.

Melatonin is considered as the time-keeping hormone acting on important physiological functions of teleosts. While the influence of melatonin on reproduction and development is well described, its potential role on immune functions has little been considered. In order to better define an immune modulation by the melatonin hormone, we hypothesized that natural variations of photoperiod and subsequent changes in melatonin release profile may act on immune status of pikeperch.

Key nutritional factors and interactions during larval development of pikeperch (Sander lucioperca).

The effects of 8 nutritional variables (Ca/P, Eicosapentaenoic acid (20:5n-3) + Docosahexaenoic acid (22:6n - 3) (EPA + DHA), Arachidonic acid (20:4n - 6) (ARA), Se, vitamins E, C, D and A) were investigated to identify their respective importance and interactions in pikeperch larval development. In this respect, two modalities (low and high levels) of each variable were tested through a fractional factorial experimental design allowing a reduction from 256 (2) to 16 (2) experimental units. Survival was significantly higher in larvae fed a high Ca/P diet while larval growth was significantly lower in larvae fed the same diet variant, associated with a higher incidence of kyphosis and pectoral anomalies in these larvae.

The importance of phospholipids combined with long-chain PUFA in formulated diets for pikeperch (Sander lucioperca) larvae.

Dietary phosphoglycerides and n-3 long-chain PUFA (LC-PUFA) play important functions in the development of pikeperch (Sander lucioperca) larvae. This study aimed to determine optimal dietary levels of soyabean lecithin (SBL)-derived phospholipids (PL) in starter feeds for pikeperch larvae 10-30 d post-hatch (DPH) and examine performance and ontogeny by additional supplementation of n-3 LC-PUFA in the form of Algatrium DHA 70 (glyceride product; 660-700 mg/g DHA; EPA 60-75 mg/g). In total, six isoproteic and isoenergetic extruded diets were formulated with increasing levels of PL (3·7, 8·3 or 14·5 % wet weight (w.

Multifactorial analyses revealed optimal aquaculture modalities improving husbandry fitness without clear effect on stress and immune status of pikeperch Sander lucioperca.

High mortality and impairment in growth rate during pikeperch (Sander lucioperca) ongrowing are among the major bottlenecks for its development in aquaculture. These failures may be related to high stress responsiveness since the rearing conditions are not yet optimized for this species. The objectives were to characterize the stress and immunological responses of pikeperch to major aquaculture modalities, and to identify the optimal aquaculture conditions for improving its welfare status.