Background In recent years, the muscle quality and texture characteristics of large yellow croaker (Larimichthys crocea), which are mainly cultured in nearshore cages, have shown a downward trend. The deep-water cage can simulate the natural ecological environment, which helps to enhance the nutritional value of L. crocea.
Objective This study aims to systematically evaluate the comprehensive benefits of offshore deep-water cage aquaculture mode.
Methods In January 2025, 30 L. crocea with similar weight from offshore deep-water cages, nearshore cages, and wild aquaculture (10 ind for each culture system) were collected for the comparative analysis of differences in morphological parameters, muscle texture and nutritional quality, and serum antioxidant capacity.
Results In body morphology indicators, the condition factor and muscle hardness of L. crocea cultured in offshore deep-water cages were similar to those of wild fish, but significantly better than those of inshore cage-cultured (P<0.05). In terms of antioxidant capacity, the offshore deep-water cages fish had significantly higher catalase activity and total antioxidant capacity than inshore cage-cultured fish (P<0.05), and showed no significant difference from wild fish (P>0.05). In terms of muscle proximate composition, the crude lipid content of fish cultured in deep-water cages was significantly higher and lower than that of wild and inshore cage-cultured (P<0.05). However, there was no difference in protein content between deep-water cages and the other two groups. In terms of fatty acid profile, the content of C18:0 in muscle of fish cultured in offshore deep-water cages was significantly higher than that of wild populations (P<0.05), while the content of C16:1n-7 was significantly lower (P<0.05). Additionally, there were no significant differences in the content of C20:5n-3, C22:6n-3, saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and n-6 and n-3 polyunsaturated fatty acids (n-6PUFA, n-3PUFA) between offshore deep-water cages and wild fish (P>0.05). Amino acid analysis revealed that the content of Thr, Met, Leu, Val, Glu, Gly, Ala, Asp, and Ser in L. crocea cultured in deep-water cages was comparable to that of wild fish (P>0.05), while the content of essential amino acids (EAA), flavor amino acids (FAA), and total amino acids (TAA) was significantly higher than that of inshore cage-cultured fish (P<0.05).
Conclusion In summary, the offshore deep-water cage culture system can significantly improve the morphological parameters, muscle texture, fatty acid composition, amino acid nutritional value, and antioxidant capacity of L. crocea, making their overall quality closer to that of wild fish. This indicated that this culture system has significant potential for the production of high-quality L. crocea and other marine economic animals. The findings of this study deliver both theoretical and practical support for enhancing the quality of L. crocea aquaculture and optimizing intensive farming techniques.
DownLoad: