饲料中D-葡萄糖含量对白鲟稚鱼的生长、脂肪合成酶及肝组成的影响

GROWTH, LIPOGENESIS AND LIVER COMPOSITION OF JUVENILE WHITE STURGEON FED DIFFERENT LEVELS OF D-GLUCOSE

以不同含量的D-葡萄糖(0%,7%,14%,21%,28%和35%)饲料饲喂白鲟稚鱼8周.7%以上各组的能量贮留和体脂含量均显著高于0%实验组,但机体的蛋白组成及贮留却不受此处理影响.饲料中D-葡萄糖含量的增加,导致稚鲟的血糖、血浆三酰甘油脂以及4种主要肝脂肪合成酶活性的提高.28%和35%两组的肝脂肪合成酶活性比0%和7%两组要大2—3倍.肝体指数、肝重及肝糖元水平均随饲料中D-葡萄糖含量的提高而逐渐增加,饲喂葡萄糖饲料各组的肝糖元水平均显著高于0%组2倍以上.

Juvenile white sturgeon (Acipenser transmontanus) were fed different levels (0%,7%, 14%, 21%, 28%, 35% ) of dietary D-glucose for 8 weeks. Fish fed diets withgreater than 7% D-glucose had significantly (P<0.05 ) greater percent body weight increase, energy retained and body lipid than fish fed the 0% glucose diet. Percent protein deposited and body protein were not affected by the dietary treatments. Increasing dietary D-glucose caused plasma glucose and triacylglycerol levels to be elevated. Liver glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, isocitrate dehydrogenase and malic enzyme activities were also greater in sturgeon fed the higher glucose diets. Fish fed the 28% and 35% glucose diets had two to three times the lipogenic enzyme activities of those fed the 0% and 7% diets, Hepatos-omatic index, liver weight and liver glycogen levels showed an increasing trend with increasing dietary D-glucose levels. Fish fed diets with D-glucose had more than twice the liver glycogen levels of fish fed the 0% glucose diet.