不同饲料营养对池塘养殖长吻(鱼危)生长性能和鱼肉品质的影响

研究通过90d的投喂实验研究不同配方饲料对池塘养殖长吻(鱼危)(Leiocassis longirostris Günther)生长性 能和鱼肉品质的影响.实验使用5种饲料 (Cont:对照、HP:高蛋白、HC:高糖、HL:高脂和HE:高能). 结果发现:HC组鱼体生长最差,而HP组特定生长率(SGR)和饲料效率(FE)都最高.鱼体水分和脂肪含量变 化趋势相反,HL组最低,HE组略高,HP组最高.鱼体脂肪主要分布于内脏,在HL和HE组显著增高,导致 出肉率(yield)显著降低,氧化产物丙二醛(MDA)增多.投喂实验结束时,鱼体背部黄度(B~*)HC组最高,HE组 其次,HP组最低,腹部红度(a~*)HE组最高,HL组次之,HP组最低.新鲜肉色各处理无差异,冰冻3d后,鱼 肉L~*和白度(△E)HE组最高,HL,组其次,Cont组最低;鱼肉a~*Cont组最高,HL组其次,HP组最低.新鲜鱼 肉硬度、胶黏性均为HP组最高,Cont组其次,HE组最低,其他肉质指标均无显著差异:结果表明:饲料营 养中脂肪是影响肉质最明显的因素,饲料脂肪通过控制鱼体成分影响鱼体体色、肉质,以及冰冻储存产生的 MDA;冰冻储存显著降低鱼肉品质,冰冻后鱼肉硬度、胶黏性、咀嚼性和系水力都明显降低,黏附性明显增 大,该指标的变化是肉质降低的表现.

EFFECT OF DIET FORMULATION ON THE GROWTH PERFORMANCE AND QUALITY OF TANK REARED CHINESE LONGSNOUT CATFISH (LEIOCASSIS LONGIROSTRIS G(U)NTHER)

A 90 day growth trial was conducted to investigate the effect of different diet formulations on the growth performance and flesh quality of tank reared Chinese longsnout catfish (Leiocassis longirostris Günther). Five diets were formulated: Cont: the control or the normal diet used for the fish; HP: high protein diet; HC: high carbohydrate diet; HL: high lipid diet; HE: high energy diet. The results showed that HC diet effected in negative growth while HP diet showed the highest specific growth rate (SGR) and feed efficiency (FE). Body water content changed in opposite direction of body lipid, and was the highest in fish of HL diet, than HE diet, and the lowest in HP diet. Most of the fish lipid was accumulated in viscera and was higher in HL and HE fed groups, which lead to significant lower yield and caused more amount of muscle maleic dialdehyde (MDA). At the end of feeding experiment, Yellowness (b~mn) of fish dorsal skin was highest in fish of HC diet, lower in HE diet and lowest in HP diet. Ventral Redness (a~*) was highest in HE diet, than HL diet, and the lowest in HP diet. Color showed no significant difference for fresh fillet until after 3d freezing when fillet Yellowness and Whiteness (AE)was decreased in the order: HE > HL > HP > Cont, and fillet Red-ness was decreased in order: Cont > HL > HE > HP. Texture of fresh fillet showed no significant difference except both Hardness and Gumminess was decreased in order: HP > Cont > HL > HE. The experiment showed that lipid was the emphasis among all diet formulations which influenced fish quality of skin color, texture and MDA content during storage by controlling fish body composition. After frozen storage, fillet Hardness, Gumminess, Chewiness and Liquid holding capacity (LHC) decreased but Adhesiveness increased perceptibly, though changes manifested decreased fish quality.