Technological approaches to grow-out: a comparative study of pikeperch (Sander lucioperca) culture in three different production systems during the growing season

This study compares pikeperch (Sander lucioperca) production in three systems:
a recirculating aquaculture system (RAS), an in-pond raceway system (IPRS), and
a traditional pond polyculture (POND). Each system was stocked with 1500
juveniles and cultured for 24 weeks. The RAS fish exhibited the most intensive
growth, achieving the highest final total length, final body weight, condition
factor and specific growth rate, alongside the lowest food conversion ratio (FCR).
However, the increased hepatosomatic index, intraperitoneal fat and ammonia
levels suggested an increased metabolism. Notably, RAS fish displayed the
highest frequency of fin erosion, particularly in the caudal and first and second
dorsal fins. The IPRS group exhibited slower growth, higher FCR and higher
plasma glucose levels than the other groups. IPRS fish also showed fin erosion in
caudal and both pectoral fins. RAS and IPRS fish demonstrated similar survival
rates. Conversely, the POND group exhibited significantly lower survival, likely
because of adaptability and water quality issues. Blood plasma analysis of POND
fish indicated starvation, marked by elevated alanine aminotransferase and lipase
levels, supported by non-existing fat reserves. In summary, RAS yielded the best
growth and feed efficiency, although it was associated with increased metabolic
stress and fin erosion. IPRS showed slower growth but proved cost-effective
during the growing season. Traditional pond culture was unsuccessful owing to
adaptability in and the water quality of ponds. An economic evaluation revealed
that production costs per pikeperch juvenile were significantly lower in the IPRS
compared with that in the RAS, thereby compensating for slower growth.