中华绒螯蟹在西藏高原条件下越冬期生化组分的变化

分析了在西藏高原条件下驯养的中华绒螯蟹(Eriocheir sinensis)越冬期间生化组分及脂肪酸组成和含量的变化。结果表明:(1)越冬前后,中华绒螯蟹肝胰腺指数显著降低,由越冬前的11.72%降为越冬后的9.96%;(2)越冬后,肝胰腺中水分及干物质组分中的总脂和蛋白质相对含量显著下降;肌肉干物质中总脂和蛋白质相对含量也显著下降,但水分相对含量显著增加。肝胰腺和肌肉中的总糖相对含量在越冬前后均没有显著性差异;(3)脂类组分中,肝胰腺和肌肉中的游离脂肪酸(FA)和磷脂(PL)相对含量在越冬后都极显著降低;而肝胰腺中的甘油三酰(TG)相对含量显著升高,肌肉中磷脂的相对含量显著上升;(4)脂肪酸组分中,肝胰腺主要的饱和脂肪酸(SFA)C16∶0、C16∶1n7和单不饱和脂肪酸(MUFA)C18∶1n9和C18∶2n6在越冬期间作为主要能源物质被动员,消耗量均在10%以上;肌肉中SFA和MUFA作为能源被动员的情况和肝胰腺中的情况类似,但值得注意的是,肌肉中多不饱和脂肪酸(PUFA)中的C20∶5n3(EPA)、C22∶6n3(DHA)虽然在越冬后相对含量有明显上升,但由于肌肉中EPA和DHA的所占比例较高(分别占肌肉总脂的23.47%和12.38%),结合肌肉中总脂的消耗情况来看,在越冬期间EPA和DHA的绝对量是下降的,表明仍有较多的EPA和DHA被消耗;(5)越冬期间,肌肉中的蛋白质和肝胰腺中的脂类均被大量消耗,表明养殖的中华绒螯蟹已受到低温和饥饿的双重胁迫。如果要提高西藏高原地区养殖中华绒螯蟹越冬后的成活率,建议在越冬前做好其相关脂类和蛋白质的营养强化。

Variations in biochemical composition of Chinese mitten crab Eriocheir sinensis acclimated to Tibetan plateau during its overwintering

The paper dealt with the proximate biochemical composition and fatty acid composition of Chinese mitten crab Eriocheir sinensis acclimated to Tibetan plateau during its overwintering by virtue of biochemical analysis.The results are as follows: (1) Hepatopancreas index (HSI) decreases significantly after overwintering, from 11.72% to 9.96%; (2) After overwintering, relative content of total lipid and protein in hepatopancreas and muscle decreases significantly, and relative content of water in hepatopancreas goes up but down in muscle significantly; Amount of saccharides showed no significant difference in both hepatopancreas and muscle during overwintering; (3) Relative content of free fatty acids and phospholipid in total lipids of hepatopancreas and muscle reduces significantly after overwintering; Relative contents of triglyceride in hepatopancreas increases but lowers in muscle significantly; (4) Among fatty acids, primary saturated fatty acids (SFA) C16:0,C16:1n7 and primary monounsaturated fatty acids (MUFA) C18:1n9 and C18:2n6 were consumed above 10% for energy metabolism during overwintering, nearly in line with SFA and MUFA burned in muscle.It was worth noting that C20:5n3(EPA) and C22:6n3(DHA)of high level in polyunsaturated fatty acid (PUFA) (23.47% and 12.38% of total lipid in muscle respectively) were also consumed, but its relative content increased to some extent after overwintering; (5) A large amount of protein in muscle and lipids in hepatopancreas are simultaneously mobilized to fuel for energy metabolism during overwintering, implying that E.sinensis cultured in Tibetan plateau is subjected to stress of both coldness and starvation.It is suggested that prior to overwintering,Chinese mitten crab acclimated to Tibetan plateau be enriched with relevant lipids and protein to improve the survival rate during its overwintering.