施氏鲟仔鱼发育圾异速生长模型

施氏鲟仔鱼的生长发育可分为两个时期:卵黄囊期(或称为自由胚期),即从刚出膜(0日龄,10.17±0.63 mm)到初次开口(9日龄,18.93±0.74 mm);晚期,从开口摄食至器官发育基本完全(38日龄,41.89±5.09 mm).卵黄囊期仔鱼的感觉、摄食、呼吸、游泳等器官快速分化;晚期仔鱼各骨板分化并发育,在形态上逐渐完成向成鱼的转变.对施氏鲟仔鱼异速生长进行的研究表明,仔鱼许多关键器官均存在异速生长现象,如眼径、口宽、尾鳍长、胸鳍长分别在2日龄、8~9日龄、10日龄、11日龄出现生长拐点,拐点之前器官快速生长,拐点之后生长速度减慢甚至近似等速生长.施氏鲟仔鱼各器官呈现出协调和快速发育的特征,随着重要的感觉、摄食、呼吸、游泳等器官的发育和完善,仔鱼快速地具备了躲避敌害和摄食的能力,其生存能力大大提高.

Development and ailometric growth patterns of larval Acipenser schrenckii

The growth and development of larval Amur sturgeon Acipenser schrenckii could be divided into two stages, i.e., pre-larval or free embryonic stage [from hatching (0 day of age and 10.17 +/- 0.63 mm of body length) to initial feeding (9 days of age and 18.93 +/- 0.74 mm of body length)], and post-larval stage [from initial feeding to juvenile stage (38 days of age and 41.89 +/- 5.09 mm of body length)]. During pre-larval stage, some organs related to feeling, feeding, breathing and swimming developed and differentiated rapidly; and during post-larval stage, dorsal, lateral and ventral scuta appeared, and the fish morphologically developed into juvenile. The growth characteristics of larval A. schrenckii presented allometric patterns, i.e., the growth inflexion points of eye diameter, mouth width, tail fin length, and pectoral fin length appeared in the ages of 2 days, 8-9 days, 10 days, and 11 days, respectively. Before the growth inflexion points, the organs grew fast; while after the growth inflexion points, the growth slowed down and approximately appeared isometric. The organs of larval A. schrenckii had the characteristics of congruous and rapid development. With the development of the organs related to feeling, feeding, breathing and swimming, larval A. schrenckii obtained the ability of escaping from predators and feeding, and consequently, its survival chance increased.