The rank of intensification factors strength in intensive pond production of common carp (Cyprinus carpio L.)

Intensive common carp (Cyprinus carpio L.) pond production offers an alternative to traditionally practiced extensive and semi-intensive farming technologies. Global warming increases the scarcity of water available for aquaculture, requiring increased productivity per unit of used water. The present trial was conducted on intensive rearing of two-summer-old common carp (0.5 +/- 0.1) kg. Fractional factorial design (2(4-1), resolution IV) was applied to identify how production performance is affected by the following four factors and their interactions: I) feeding rate: ad libitum (4%) vs. restricted (2%); II) stocking density: low (1.1 t/ha) vs. high (2.2 t/ ha); III) aeration rate: low (11 kW/ha) vs. high (25 kW/ha); and IV) presence or absence of co-cultured species: monoculture vs. polyculture with pikeperch (Sander lucioperca L.) reared in cages. The feeding rate appeared to be the most influential factor in growth, meat quality, water quality, and stress parameters. Although the higher stocking density might be economically justified in the short term, due to impaired welfare it brings risks in the long run. The higher rate of artificial aeration showed a negative effect on meat and water quality; however, its cooling effect might be helpful in tackling issues with extreme water temperature. The test showed feasible cage production of pikeperch even in intensive pond production. The recommended goals for feasible intensification of common carp pond aquaculture are feeding regimes aiming at better feed utilization instead of growth maximization, stocking densities up to the limits of fish welfare (gross yield <11 t/ha), optimized paddle wheel aeration in favor of algae development (<11 kW/ha), and species/technology diversification.