饥饿对太平洋鲑生长、机体组成及血浆相关生化指标变化研究

实验研究了太平洋鲑鱼(Oncorhynchus spp.)经8—32d饥饿后对其生长、体组成与血浆生化指标变化的影响。90尾初始重约为217g的太平洋鲑鱼放养于0.25m3的水族箱中0—32d,水温为(17.0±2.9)℃。实验分5组,分别为对照组(饥饿0d)、实验1组(饥饿8d)、实验2组(饥饿16d)、实验3组(饥饿24d)、实验4组(饥饿32d)。每组3个平行,每箱6尾鱼。结果表明:饥饿期间,太平洋鲑鱼存活率均为100%,相对体重损失率与饥饿时间直线回归方程为y=0.0086x(R2=0.9177),呈显著的正相关(P0.05);肠系膜脂肪是太平洋鲑鱼最主要的能量来源,与饥饿时间呈显著的负相关(P0.05),其直线回归方程y=-0.0719x±4.11(R2=0.9732);饥饿初期太平洋鲑鱼主要消耗肝脏糖原和脂肪、部分肠系膜脂肪和少许肌肉中脂肪维持生命活动,能耗较低;饥饿后期主要以消耗肠系膜脂肪、部分肌肉脂肪和少量蛋白质维持生命活动,能耗较高;血浆中脂肪分解酶和白蛋白无显著变化(P0.05),胆固醇、甘油三酯和高低密度脂蛋白有显著波动(P0.05),表明脂肪代谢活跃,免疫功能未受明显影响。研究表明太平洋鲑鱼能够有效地利用体内储存的脂肪,对饥饿的耐受能力较强。

THE EFFECTS OF STARVATION ON GROWTH, PROXIMATE COMPOSITION AND BIOCHEMICAL INDEX OF PLASMA OF PACIFIC SALMON (ONCORHYNCHUS SPP.)

This experiment was conducted to determine the effects of starvation on growth, proximate composition and the biochemical index of plasma of Pacific Salmon (Oncorhynchus spp.). 90 Pacific Salmon with an average weight about 217g were randomly stocked in five-test aquarium (0.25m~3), which was starvation from 0 to 32d. The rearing water temperature was 17.0±2.9℃. 18 fish (six fish from each triplicate aquarium) were sampled at 0, 8, 16, 24 and 32d of each starvation group, respectively. The experiment indicated that no mortality or physical abnormal sign was ob-served in any test group throughout the experiment. Starvation for 32d, the weight was decreased by 7.50% and the relative loss rate of weight was 0.175% on average. At the same time, the relative loss rate of weight and the starvation time had the positive correlation (P<0.05), linear regression equation was y = 0.0086x (R~2 = 0.9177). The lipid of the mesentery was as the main source of the energy, and it had the negative relation with the starvation time, linear regres-sion equation was Y = -0.0719x ± 4.11 (R~2 = 0.9732). Pacific salmon consumed liver fat and hepatic glycogen mainly in the early starvation stage and its energy consumption was relatively low. On later starva. m stage, it mainly consumed mesentery fat, some muscle fat and some proteins for energy source, its energy consumption rose obviously. Lipolytic enzyme (LIPA) and albumin (ALB) did not have significantly difference in the test groups compared with the control group (P > 0.05). The cholesterol (CH), triglyceride (TG) and high-density lipoprotein (HDL) had significant difference among the groups (P < 0.05) and it improved that the metabolic of lipid was active. Pacific salmon had the definitive ability of tolerating starvation relatively better for using the lipid storied in body.