脱脂南极磷虾粉对圆斑星鲽幼鱼体组成和消化性能的影响

为探讨脱脂南极磷虾(Euphausia superba)粉对圆斑星鲽(Verasper variegatus)幼鱼体组成和消化性能的影响。作者以鱼粉和脱脂磷虾粉为蛋白源、鱼油为脂肪源,用脱脂磷虾粉蛋白替代0%、10%、20%、30%、40%、50%和100%的鱼粉蛋白,设计7种等蛋白(50%)、等脂肪(8%)的实验饲料(分别表示为F0、F10、F20、F30、F40、F50和F100)。每组设3个重复,每个重复20尾鱼,初始体质量为(68.13±0.20)g,经过8周的饲养实验。结果表明:F100组的肝体比和脏体比显著低于其他各组(P0.05),F20~F30组的肥满度显著高于F40组(P0.05);F100组全鱼的水分和灰分显著高于其他各组(P0.05),F10组和F100组全鱼的粗蛋白显著高于其他各组(P0.05),F30组和F50组全鱼的粗脂肪显著高于其他各组(P0.05),F100组全鱼的粗脂肪显著低于其他各组(P0.05)。F10、F20和F50组肌肉的水分显著高于F100组(P0.05),F20组和F30组肌肉的粗脂肪显著高于其他各组(P0.05),各替代组肌肉的粗蛋白、灰分无组间差异(P0.05);胃蛋白酶活性组间无差异(P0.05),F0和F20的胃脂肪酶活性显著低于F30组(P0.05),F30组的胃淀粉酶活性显著高于其他各组(P0.05),F30和F100组的肠脂肪酶活性显著低于其他各组(P0.05),F0组的肠淀粉酶活性显著高于其他各组(P0.05);脱脂南极磷虾粉替代组的皱襞高度呈现先升高后降低的趋势,F30组的皱襞高度显著高于其他组(P0.05),替代组和对照组的黏膜厚度和绒毛长度没有显著性差异(P0.05)。综合来看,脱脂南极磷虾粉10%~50%的替代比例对圆斑星鲽幼鱼的形态指标、体组成、消化酶活性和肠道形态指标有较好的效果。

Effects of dietary skimmed krill meal on the body composition and digestive ability of juvenile spotted halibut (Verasper variegatus)

While both fishmeal and skimmed krill meal (SKM) are considered the main source of protein, fish oil has been used as a source of lipid. This study aims to determine the optimum level of SKM (in replacement of the fishmeal) in the diet for spotted halibut (Verasper variegatus). We conducted an 8-week experiment in which the seven isocaloric and isonitrogenous diets contained 0%, 10%, 20%, 30%, 40%, 50%, and 100% SKM. We provided each diet randomly to a triplicate of 15 fish (60.13 g ± 0.20 g) per tank in the indoor culture system. The results revealed that the viscerosomatic index and hepatosomatic index of other groups were higher than those in the F100 group (P < 0.05). The condition factor of F20-F30 groups was higher than that in the F40 group (P < 0.05). In addition, the whole-body moisture and ASH of the F100 group were higher than those of other groups (P < 0.05); the whole-body crude protein of the F10 and F100 groups was higher than that in other groups (P < 0.05); and the whole-body crude fatty of the F30 and F50 groups was higher than that in other groups (P < 0.05). Furthermore, the muscle moisture of the F10, F20, and F50 groups was higher than that of the F100 group (P < 0.05); the muscle crude protein and ASH of the F10-F100 groups were similar to those of the F0 group (P > 0.05); and the muscle crude fat of the F20-F30 groups was higher than that in other groups (P < 0.05). We observed no significant difference in the pepsin of juvenile spotted halibut among groups (P > 0.05). While the stomach lipase of the F0 and F20 groups were lower than that of the F30 group (P < 0.05), the stomach amylase of the F30 group was higher than that of other groups (P < 0.05). Although the intestinal amylase of the F0 group was significantly higher than that of other groups (P < 0.05), the intestinal lipase of the F30 and F100 groups was lower than that of other groups (P < 0.05). Finally, the fold height of the F30 group was significantly higher than that of other groups (P < 0.05); however, the mucosal thickness and villus length of juvenile spotted halibut exhibited no significant difference among groups (P > 0.05). This study suggests that 10%?50% of SKM levels exert similar effects on the body composition and digestive ability of juvenile spotted halibut.