金乌贼(Sepia esculenta)繁殖模式的分子学鉴定

摘要

我国金乌贼自然资源日渐衰退,为制定相应的保护措施,需要对金乌贼的繁殖模式进行分析研究.本实验在青岛海域采捕活体金乌贼成体22只,进行室内繁育.根据形态学判定参与受精产卵雌性有2只(F8,F18)雄性18只.为了进一步探索金乌贼的繁殖模式,对雌体F2纳精囊处交配后留下的精荚中的精子进行了微卫星DNA标记检测,发现至少2个雄性参与交配行为;同时,随机选取子代幼体87只,利用8个DNA微卫星位点进行亲权鉴定.结果表明:F8个体是42只幼体的母本,而剩余45只的母本是F18,由F8产卵孵化的幼体潜在父本是M4和M5,由F18产卵孵化的幼体潜在父本是M12和M13,每一个雌性可能与至少2个潜在雄性交配并受精.分析结果显示金乌贼繁殖模式存在一雌多雄关系,为科学维持和保护原种基因库,有的放矢地进行繁育、增养殖和人工放流工作提供重要支撑.%Sepia esculenta is a valuable and important fishery resource for China,Japan and Korea.However,this fishery has experienced severe population decline largely in past decades.To provide guidelines for fisheries protection management,it is necessary to study the reproduction model of S.esculenta.We sampled 22 parent individuals of S.esculenta in Qingdao waters of Yellow Sea.By morphological observation,2 females (F8,F18) and 18 males took part in mating.To explore their reproduction characteristics,sperms located in the seminal receptacle of F2 were detected by microsatellite DNA markers.It showed that at least 2 males mated with the same female.Meanwhile,we randomly selected 87 offsprings,and analyzed the paternity relationship by 8 microsatellite loci.We found that 42 offsprings were from F8,whose fathers might be M4 and M5;and 45 offsprings from F18,whose fathers might be M12 and M13.Each female parent mated probably with at least two male parents,and then impregnated with them.Therefore,the reproduction model of S.esculenta is polygamous,which provides a good reference for resource conservation and restoration in breeding,aquaculture,and artificial releasing of the species.