越冬和产卵洄游期黄海鳀鱼对能量的利用差异

Differential utilization of energy during wintering and spawning migration of anchovy in the Yellow Sea

根据2002年6月至2003年9月黄海中南部水域的鱼(Engraulisjaponicus)样品,分析越冬和产卵期间鱼能量利用差异。结果显示,各个月份鱼性腺指数(GSI)和腹腔含脂量等级呈负相关。越冬和产卵期间鱼体脂肪消耗速率有显著差异,纯鱼体脂肪消耗速率也有相似变化。摄食期间(3～5月)黄海积累大量脂肪作为能量储备,产卵前期(5月)个别鱼全鱼体脂肪含量超过40%,平均脂肪含量达15%,产卵过后平均脂肪含量水平下降了10%～11%。然而,越冬期间(11～1月)脂肪含量变化幅度很小。产卵期间(5～7月)全鱼体脂肪含量与性腺重量(性腺成熟度为Ⅳ或Ⅴ期)呈显著正相关。叉长和性腺重量(性腺成熟度为Ⅳ或Ⅴ期)也呈显著正相关。越冬期间全鱼体和纯鱼体的固体物质(蛋白质)含量比产卵期间低1%～2%。各个月份全鱼体固体物质(蛋白质)含量比纯鱼体低1%左右。越冬期间各叉长组能量变化很小,而产卵期间月能量消耗则随叉长呈指数增长。能量损失主要是脂肪新陈代谢造成,而存储蛋白质主要用于性腺发育,并且在越冬和产卵期间全鱼体的蛋白质含量保持相对常量。

Based on the surveys of anchovy in the central and southern waters of the Yellow Sea from June 2002 to September 2003,differential utilization of energy during wintering and spawning migration of anchovy was analyzed.A significantly negative correlation was found between GSI and mesenteric fat amount monthly from 2002 to 2003.GSI decreased significantly in spawning period (May-August),and it was about 1% in the last ten days of August,so this meant the end of the spawning activities;then the stomach fullness increased obviously.There was a significantly different utilization of fat loss in the whole body of anchovy in wintering and spawning periods;the similar change was found in the whole body (minus guts) of anchovy.Anchovy accumulated much fat as energy storage in the feeding period (March-May).The fat of some individual anchovy in pre-spawning period (May) had more than 40%,and that of average values was 15% and decreased by 10%-11% after spawning.However,the fat had little change in wintering period (November-January).There was a significantly positive correlation between fat and gonad weight in the whole body of anchovy (mature stages Ⅳ or Ⅴ) in spawning period (May-July).There also was a significantly positive correlation between fork length and gonad weight.Solids (protein) content in both of the whole body and the whole body (minus guts) of anchovy in wintering was lower than that in spawning period by 1%-2%.Solids (protein) content in the whole body was lower than that in the whole body (minus guts) of anchovy by about 1% in each month.Few changes were found in length-specific energy content in wintering period,but an exponential increase relation was found in length-specific monthly energy loss.The energy depletion was mainly induced by fat metabolism;while the storage protein was used by the maturation of gonads and protein content was in a constant amount in the whole body in wintering and spawning periods.