盐度对卵形鲳鲹幼鱼渗透压调节和饥饿失重的影响  

Effects of salinity on the osmoregulation and weight loss from starvation in Trachinotus ovatus juvenile

作　　者：区又君[1] 范春燕[1,2] 李加儿[1] 于娜[1,2] 

机构地区：[1]中国水产科学研究院南海水产研究所农业部南海渔业资源开发利用重点实验室,广州510300 [2]上海海洋大学水产与生命学院,上海201306

出　　处：《生态学报》2014年第24期7436-7443,共8页Acta Ecologica Sinica

基　　金：国家“863”项目(2006AA10A414);中国水产科学研究院基本科研业务费资助项目(2012A0401,2013A0501)

摘　　要：为探讨盐度对卵形鲳鲹(Trachinotus ovatus)渗透压调节的影响,研究了深水网箱养殖的卵形鲳鲹幼鱼鳃Na+-K+-ATP酶(NKA)活性,血浆、鳃和肾渗透压以及饥饿失重在盐度渐变条件下的反应。实验设5个盐度梯度组,分别为5、15、25、30和35。结果显示,鳃NKA活性除盐度15外都呈先下降后升高随之回落并趋于稳定的趋势,在2 d后的各时间节点随盐度变化呈"U"型分布;血浆渗透压在相同盐度下随时间延长呈先升高后下降再升高随后回落并趋于稳定,2 d后在各时间节点与盐度呈正相关关系,盐度30和35组的血浆渗透压显著高于其它盐度组(P<0.05);肾脏对盐度变化的渗透调节比鳃敏感,在低盐度时(30以下),鰓和肾共同完成对渗透压的调节,在较高盐度(30以上),肾对渗透压的调节起主导作用。盐度变化对卵形鲳鲹的饥饿失重率有极显著的影响。研究表明,卵形鲳鲹幼鱼对盐度的渗透调节能力较强,在盐度5—35范围内的盐度变化均能适应,一般在1—2 d内可达到稳定,且更适于在低盐度水环境中生活。Effects of gradual salinity changes on the gill NKA activities,plasma,gill,and kidney osmolarity and weight losing rate from starvation of Trachinotus ovatus juvenile reared in the deep water net-cage were studied in order to understand the mechanism of osmoregulatory adaptation in this fish. Experimental fish with the mean total length of（ 8.058±0.843） cm and body mass of（ 9. 010 ± 1. 537） g were reared in the glass aquariums（ 80 cm × 40 cm × 50 cm） with five salinity treatments in triplicate,including 5,15,25,30 and 35 ‰. The water temperature and dissolved oxygen were maintained at（ 30 ± 3） ℃ and（ 6. 5 ± 0. 3） mg / L throughout the experiment,and the p H varied from 8. 0 to 8. 8 as the changes of salinity. On 12 days after transferring to the target salinities,the survival rates of the juveniles in treatments of salinity 5,25 and 35 were 87.14%,95.71% and 88.86%,respectively,and no mortalities were recorded in the treatment of salinity 15 and 30. Gill NKA activities of fish from the salinity of 5,25,30 and 35 decreased at the beginning of the trial and then increased and decreased afterwards,and maintained at stable levels. After accumulated in the target salinities two days,the gill NKA activities followed a ＂U ＂-shape developmental trends with salinity change at the same time. NKA activities were found stable in both control（ salinity 30） and the salinity of 25 treatments,indicating a stronger adaptivecapacity of fish to lower salinity than that to the higher salinity. Plasma osmolarity was sensible to salinity changes,increased at the beginning of the trial and then decreased and increased afterwards and then decreased,and maintained at stable levels at the same salinity. Significant changes in plasma osmolarity were found in all the salinity treatments at the first two days of the experiment（ P 〈 0.05） varying within wide limits in high salinity treatment than that in low ones. The variations of the plasma osmolarity were significantly higher in the salinity trea

关 键 词：卵形鲳鲹 盐度渐变 NA+-K+-ATP酶 渗透压 饥饿失重 

分 类 号：S965.399[农业科学—水产养殖]