Factors that may affect the quality and safety of certain aquaculture fish species

Abstract

This study provides an integrated assessment of environmental, nutritional, technological, and veterinary-sanitary factors influencing the quality and safety of freshwater aquaculture species, focusing on common carp and silver carp. The research was conducted between 2023 and 2024 at the Nucet Research and Development Station for Aquaculture (S.C.D.P.-Nucet), through continuous monitoring of meteorological, physicochemical, biological, and microbiological water parameters. Results revealed a moderate increase in water temperature (0.5–1.0 °C) and a decrease in dissolved oxygen levels, associated with local climatic variability. Heavy metal concentrations (Pb, Hg, Cd) remained well below permissible limits, and both water and fish tissue samples tested negative for pathogens (Salmonella spp., Listeria monocytogenes). Microbiological indicators (TVC < 10⁴ CFU/mL in water; < 10² CFU/g in fish tissue) confirmed appropriate sanitary conditions. Correlation of the physicochemical and biological data demonstrated efficient selfpurification processes and ecological stability of the ponds. The findings emphasize the role of integrated multitrophic aquaculture (IMTA) and recirculating aquaculture systems (RAS) as sustainable strategies to maintain environmental quality, ensure food safety, and enhance the resilience of Romanian aquaculture to climate change.