Effects of chilled trash fish and formulated feed on growth performance, feed utilization and muscle nutrient quality of yellow drum (Nibea albiflora)

Nibea albiflora is an important cage-cultured fish in the East China Sea. We carried out studies on the nutritional requirements and metabolic regulation of juvenile N. albiflora, and developed a special formulated feed for N. albiflora An 8-week feeding trial was conducted to evaluate the effects of special formulated feed and chilled trash fish on growth performance, feed utilization and muscle nutrient quality of N. albiflora. 540 healthy yellow drum with initial body weight of (34.60±0.05) g were randomly divided into 3 groups, three replicates in each group, which were fed special formulated feed, commercial formulated feed and chilled trash fish throughout the feeding trial. Results indicated that the weight gain rate (WGR), specific growth rate (SGR), and protein efficiency rate (PER) of fish fed special formulated feed were 211.52%, 2.03%/d, and 160.92%, respectively, which were significantly higher than those of fish fed chilled trash fish diet (149.97%, 1,64%/d, 67.04%) and commercial formulated diet (187.33%, 1.88%/d, 144.37%) (P<0.05). The feed conversion rate (FCR) of fish fed chilled trash fish was significantly higher than those of fish fed formulated feed (P<0.05). The fish fed formulated feed had a significantly higher HSI and VSI compared with that of fish fed chilled trash fish (P<0.05). The muscle lipid content of fish fed special formulated feed was significantly higher than those of fish fed commercial formulated feed and chilled trash fish, and the muscle moisture content was significantly lower than those of fish fed commercial formulated feed and chilled trash fish (P<0.05). The total amino acid (TAA), essential amino acid (EAA), ARA and DHA contents of fish fed chilled trash fish were significantly higher than those of fish fed formulated feed (P<0.05). The H.E staining result of muscle tissue indicated that muscle fibers of fish fed formulated feed and chilled trash fish were irregular polygon with clear texture and tight arrangement, however, the muscle fiber density of fish fed chilled trash fish was significantly higher than those of fish fed formulated feed (P<0.05). In conclusion, the growth performance and feed utilization of fish fed special formulated feed were better than those of fish fed chilled trash fish. However, the muscle amino acids and LC-PUFA contents of fish fed chilled trash fish were better than those of fish fed special formulated feed. This study can provide a theoretical basis for the efficient and healthy culture of N. albiflora and the optimization of its formulated feed.