Investigation of the nutritional compositions of fish species obtained from natural and aquaculture conditions in Hirfanli dam lake

The nutrient content and fatty acid compositions of fish can vary significantly depending on numerous biological and environmental factors such as species, age, gender, habitat, and seasonal variables. In this study, the body chemical compositions of five different species obtained from their natural environment in Hirfanlı Dam Lake, farmed trout held in cage culture conditions, and escapee trout that fled into the lake from cage systems were compared. Ten individuals from each fish species and group were sampled. The analyses revealed that the crude fat ratios of fish caught from natural waters differed significantly from those obtained from aquaculture systems (P≤0,05). The highest crude fat ratio was determined in fish from the farm cage system (%8,89±0,92) while the lowest ratio was observed in the natural individuals (%0,89±0,14). Protein contents also showed significant differences between the groups (P≤0,05). with the highest protein content similarly detected in the farm cage group (%18,73±0,78). Regarding the fatty acid profile, the lowest level of Total Saturated Fatty Acids (SFA) was observed in the trout lake group, and the highest value was observed in silver fish (P≤0,05). Total Monounsaturated Fatty Acids (MUFA) were detected at the highest level in carp, and the lowest MUFA content was found in pikeperch and silver fish (P≤0,05). In terms of Total Polyunsaturated Fatty Acids (PUFA), the highest value was found in pikeperch (%43,31±0,82), while the lowest value was detected in carp (%23,04±0,49). Total ω-6 fatty acids were high in trout species and low in other natural species, whereas, conversely, Total ω-3 fatty acids were found to be high in natural species (P≤0,05). Similarly, differences were observed among the fish in terms of total amounts of EPA and DHA (P≤0,05). Atherogenic Index (AI) and Thrombogenic Index (TI) values were found to be highest in silver fish and carp, respectively (P≤0,05). In conclusion, although significant differences were found in the body chemical compositions between the species caught from Hirfanlı Dam Lake and the fish obtained from aquaculture conditions, all species, especially the natural ones, were determined to be recommendable for human consumption.