斑点叉尾鮰胚胎和幼苗发育的观察
OBSERVATIONS ON THE EMBRYONIC AND LARVAL DEVELOPMENT OF CHANNEL CATFISH
- 
                            摘要: 斑点叉尾鮰卵为圆球形、桔黄色,属于沉性,透明并具有粘性,卵与卵之间的粘性较强,产出时互相粘合成不规则的块状。卵的平均直径为3.457 mm,受精卵在水温 25.5—29℃时,出膜时间为146小时56分钟(6 天以上)。孵化出膜的仔鱼呈金黄色,卵黄桃红色,体较透明,体全长 7.89—8.13 mm,平均为7.95 mm。出膜4天后,开始摄食,转入混合营养阶段,10天左右器官分化完善。出膜后仔鱼集群堆积于水体底部。眼晶体、黑色素和嗅囊出现,心脏形成和搏动,内耳、尾和胸鳍原基形成,开始血液循环及红色素,鳃弓、鳃丝和鳃盖原基形成,消化道、肛门和肝脏等均在出膜之前形成。Abstract: The present paper deals with the embryonic and larval developmentof channel catfish (Ictalurus punctatus). The fertilized eggs of the catfish are tran-sparent, orange in colour and adhesive. The average diameter of eggs is 3.457mm.The feritlized eggs hatched out in 146 hours and 56 minutes (about 6 days) at thewater temperature of 25.5--29℃. Newly hatched larva attains a length of 7.89--8.13mm are golden-yellowishwith the yolk sac pinkish light amber in colour. The larva begins to feed at 4 daysand its morphogenesis completes at 10 days after hatching. Lens, ocular pigmenta-tion, smell vesicles, heart beating, inner ears, tail, anlage of pectoral fins, bloodcirculation and erthrocyte, gill arches, gill filamento and the anlage of gill covers,digestive tract, anus and livers all complete before hatching.
 
                
下载: