鳜仔稚鱼骨骼系统骨化发育

采用软骨―硬骨双染色技术,描述了鳜(Siniperca chuatsi)仔稚鱼(1～35日龄)头骨、脊柱、附肢骨骼的骨化发育特征。结果显示:(1)头骨前鳃盖骨于14日龄最先骨化, 15日龄上下颌骨骨化,且上下颌骨相对长度呈现连续变化过程。17日龄后,颌齿、关节骨、舌颌骨骨化;19日龄,隅骨、间鳃盖骨、鳃盖骨、鳃条骨、额骨骨化。20日龄后,方骨、下鳃盖骨、辅上颌骨等骨化; 35日龄,头骨骨化基本完成。(2)脊柱于15日龄由前向后骨化, 20日龄背肋与腹肋由基部向末端骨化, 29日龄骨化完成。脉弓与脉棘、髓弓与髓棘均由前向后、由基部向末端骨化,脉棘与髓棘骨化时间晚于相应的椎体。(3)附肢骨骼骨化顺序依次为胸鳍、背鳍、臀鳍、腹鳍、尾鳍。胸鳍匙骨于16日龄骨化,乌喙骨与肩胛骨于25日龄骨化;背鳍、臀鳍分别于18日龄、20日龄骨化,骨化方式相似;腹鳍于23日龄骨化,骨化方式与胸鳍相反;尾杆骨、尾下骨于25日龄骨化,附肢骨骼于35日龄基本骨化完成。结果表明,鳜骨骼骨化发育与其早期运动、摄食与御敌等行为密切相关。

Early ossification of the skeletal system in larval and juvenile Siniperca chuatsi

Siniperca chuatsi is a freshwater fish with high economic value and is endemic to East Asia. Some studies have shown that mandarin fish exhibit different movement modes, feeding behavior, and nutritional demands during the larvae and juvenile stages. In this study, the morphological ossification characteristics of the skulls, vertebrae, and appendages of S. chuatsi larvae1-35 days post hatching (dph)] were described using a cartilage bone clearing and staining technique to provide information on the larval and juvenile organ structure development and functional adaption. The results showed that the preopercle of the skull began ossification at 14 dph. The upper and mandibular structure, which showed a relative length change, was ossified at 15 dph. At 17 dph, the jaw teeth, articular, and hyomandibular began to ossify, while the interopercle, angular, opercle, branchiostegal ray, and frontal structures were ossified at 19 dph. At 20 dph, the quadrate, subopercle, and supplementary maxilla were ossified; most of the skull was completely ossified by 35 dph. Ossification of the vertebrae began at 15 dph from the anterior to the posterior and was completely ossified by 29 dph. The dorsal rib and ventral rib began to ossify from the base to the outside at 20 dph. The haemal arch, haemal spine, neural arch, and neural spine from the front to back and the base to the distal end were ossified. Ossification of the haemal spine and neural spine occurred later than that of the corresponding vertebrae. The ossification order of the appendages was from the pectoral fin to the dorsal fin, anal fin, pelvic fin, and caudal fin. The cleithrum of the pectoral fin was ossified at 16 dph, while the coracoid and scapula were ossified at 25 dph. The dorsal fin and anal fin were ossified at 18 and 20 dph, respectively. The pelvic fins were ossified from the middle to both ends at 23 dph and the ossification pattern was opposite to that of the pectoral fin. The urostyle and hypural of the caudal fin began to ossify at 25 dph. The appendicular skeleton was fully ossified at 35 dph. The results showed that the early skull ossification of S. chuatsi larvae and juveniles is closely related to their feeding and defense behavior, while ossification of the vertebrae and appendages are closely related to their movement and avoidance of the enemy.