荚膜甲基球菌蛋白替代鱼粉对卵形鲳鲹生长和抗氧化能力的影响

METHANOTROPH(METHYLOCOCCUS CAPSULATUS, BATH) BACTERIA MEAL REPLACEMENT OF FISHMEAL ON GROWTH, LIPID DEPOSITION AND ANTIOXIDANT CAPACITY OF TRACHINOTUS OVATUS

实验旨在研究荚膜甲基球菌(Methylococcus capsulatus, Bath)蛋白(MBM,斐康?蛋白)替代鱼粉对卵形鲳鲹生长性能和抗氧化能力的影响。MBM添加量分别为0、3.5%、7%和10.5%,替代基础饲料中鱼粉(含量35%)0、10%、20%和30%,制得4组等氮等脂饲料,即MBM0、MBM10、MBM20和MBM30组,饲喂卵形鲳鲹幼鱼[初始均重(34.88±1.13) g]56d。实验结果显示,随着饲料中MBM含量的升高,各组间的末均重、增重率、特定生长率、存活率、肝体比、脏体比和饲料系数均无显著性差异(P>0.05)。MBM30组肥满度显著高于MBM0组(P<0.05)。各组全鱼粗蛋白含量无显著差异(P>0.05), MBM20组全鱼粗脂肪含量显著高于MBM0组和MBM10组(P<0.05)。MBM20组和MBM30组背肌粗脂肪含量显著高于MBM0组(P<0.05),背肌粗脂肪与MBM替代鱼粉的比例呈显著正相关关系(P<0.05)。MBM20和MBM30组血清甘油三酯显著低于MBM0组(P<0.05), MBM20组血清谷草转氨酶活性显著高于MBM0组(P<0.05), MBM10组血清白蛋白显著高于MBM0组(P<0.05)。MBM20组血清总抗氧化能力与MBM0无显著性差异(P>0.05),显著高于MBM10和MBM30组(P<0.05), MBM20组肠道超氧化物歧化酶活性显著高于其余各组(P<0.05), MBM20组和MBM30组肝脏HE染色切片中空泡面积显著高于MBM0组(P<0.05)。综上所述,在基础饲料鱼粉含量为35%时, MBM可以替代20%—30%的鱼粉且不会对卵形鲳鲹的生长性能、形态学指标、体成分和血清生化指标产生负面影响。

The effects of methanotroph(Methylococcus capsulatus, Barh) bacteria meal(MBM, FeedKind?) replaces fishmeal(FM) on the growth performance and antioxidant capacity of Trachinotus ovatus(initial mean weight34.88±1.13 g) were conducted through a 56-day breeding trial. MBM at 0, 3%, 7% and 10.5% were added to replace fishmeal at 0, 10%, 20% and 30%, to formulate four isonitrogenous and isolipidic feeds named MBM0, MBM10,MBM20 and MBM30, respectively. The results of the experiment showed that there was no significant difference in the final mean weight, weight gain rate, specific growth rate, survival rate, hepatosomatic index, visceral index and feed factor between the groups as the MBM content in the diets increased(P>0.05). The condition factor of the MBM30group was significantly higher than that of the MBM0 group(P<0.05). The crude protein content of whole fish in each group was not significantly different(P>0.05), while the crude fat content of whole fish in the MBM20 group was significantly higher than that in the MBM0 and MBM10 groups(P<0.05). The crude fat content of dorsal muscle in the MBM20 and MBM30 groups was significantly higher than that in the MBM0 group(P<0.05), and there was a significant positive correlation between the crude fat content in dorsal muscle and the proportion of fishmeal replaced by MBM(P<0.05). Serum triglycerides were significantly lower in the MBM20 and MBM30 groups than those in MBM0group(P<0.05), serum glutathione transaminase activity was significantly higher in the MBM20 group than that in the MBM0 group(P<0.05), and serum albumin was significantly higher in the MBM10 group than those in MBM0 group(P<0.05). Total serum antioxidant capacity in MBM20 group was not significantly different with the MBM0 group(P>0.05), while significantly higher than that in the MBM10 and MBM30 groups(P<0.05). Intestinal superoxide dismutase activity in the MBM20 group was significantly higher than that in the rest of the groups(P<0.05). Vacuolar area in liver through H&E-stained was significantly higher in the MBM20 and MBM30 groups than that in the MBM0group(P<0.05). In conclusion, at 35% fishmeal content in the basal diet, MBM could replace 20%—30% of fishmeal without negatively affecting growth performance, morphological indices, body composition and serum biochemical indices of Trachinotus ovatus.