Abstract：
The present study explored the effects of different lipid sources on growth performance, lipid deposition, antioxidant capacity, inflammatory response and disease resistance of largemouth bass (Micropterus salmoides). Four isonitrogenous (crude protein 50.46 %) and isolipidic (crude lipid 11.12 %) diets were formulated to contain 7 % of different oil sources including fish oil (FO) (control), soybean oil (SO), linseed oil (LO) and coconut oil (CO). Largemouth bass with initial body weight of 36.0 ± 0.2 g were randomly distributed into 12 tanks, with 30 fish per tank and 3 tanks per treatment. The fish were fed with the experiment diets twice daily for 8 weeks. The results indicated that the weight gain of largemouth bass fed the FO diet was significantly higher than that of fish fed the LO and CO diets. The liver crude lipid content in FO group was significantly higher than other groups, while the highest liver triglyceride content was showed in SO group and the lowest was detected in LO group. At transcriptional level, expression of lipogenesis related genes (pparγ, srebp1, fas, acc, dgat1 and dgat2) in the SO and CO group were significantly higher than the FO group. However, the expression of lipolysis and fatty acids oxidation related genes (pparα, cpt1, and aco) in vegetable oils groups were significantly higher than the FO group. As to the antioxidant capacity, vegetable oils significantly reduced the malondialdehyde content of largemouth bass. Total antioxidant capacity in the SO and LO groups were significantly increased compared with the FO group. Catalase in the LO group was significantly increased compared with the FO group. Furthermore, the ER stress related genes, such as grp78, atf6α, atf6β, chop and xbp1 were significantly enhanced in the vegetable oil groups compared with the FO group. The activity of serum lysozyme in vegetable oil groups were significantly higher than in FO group. Additionally, the relative expression of non-specific immune related genes, including tlr2, mapk11, mapk13, mapk14, rela, tgf-β1, tnfα, 5lox, il-1β and il10, were all significantly increased in SO and CO groups compared to the other groups. In conclusion, based on the indexes including growth performance, lipid deposition, antioxidant capacity and inflammatory response, SO and LO could be alternative oil sources for largemouth bass.
摘要：
本研究探讨了不同脂源替代鱼油对生长性能的影响,脂质沉积，抗氧化能力，大口鲈鱼（Micropterussalmoides）的炎症反应和抗病性。配制了四种同氮（粗蛋白50.46％）和异碘（粗脂质11.12％）的饮食，以含有7％的不同油源，包括鱼油（FO）（对照），大豆油（SO），亚麻籽油（LO）和椰子油（CO）。将初始体重为36.0±0.2g的大嘴鲈鱼随机分配到12个坦克中，每个鱼缸30条鱼，每次处理3个鱼缸。每天两次给鱼喂食实验饮食,持续8周。结果表明，饲喂FO日粮的大嘴鲈鱼的体重增加明显高于饲喂LO和CO日粮的鱼。FO组肝脏粗脂肪含量显著高于其他组,SO组肝脏甘油三酯含量最高，LO组最低。在转录水平，脂肪生成相关基因的表达(pparγ，srebp1,fas,acc,SO和CO组的dgat1和dgat2）明显高于FO组。然而,脂解和脂肪酸氧化相关基因的表达(pparα，植物油组的cpt1和aco）显着高于FO组。至于抗氧化能力，植物油可显着降低大嘴鲈鱼的丙二醛含量。与FO组相比，SO和LO组的总抗氧化能力显着增加。LO组过氧化氢酶较FO组显著增高。此外，ER应激相关基因，例如grp78，atf6α，atf6β，与FO组相比，植物油组的chop和xbp1显着增强。植物油组血清溶菌酶活性明显高于FO组。此外,非特异性免疫相关基因的相对表达，包括tlr2,mapk11,mapk13,mapk14,rela,tgf-β1，tnfα，5lox,与其他组相比，SO和CO组的il-1β和il10均显着增加。总之,根据包括增长业绩在内的指标，脂质沉积，抗氧化能力和炎症反应，SO和LO可能是大嘴鲈鱼的替代油源。
