采用实验生态学方法,进行了鮸鱼仔稚鱼发育生长方式及其生态学意义研究。结果表明,鮸鱼的形态学变化和器官分化主要发生在仔鱼期。仔鱼期头部和尾部快于躯干部的生长。仔鱼头部(拐点:9.80mm体长)、眼径(8.87mm)和口径(23.40mm)的正异速生长为仔鱼的呼吸和摄食提供了有利条件;尾长(16.40mm)正异速生长为减少仔鱼运动能耗和成功逃避捕食者准备了条件;虽然躯干部生长比较缓慢,但是体高呈现正异速生长(11.20mm),这可能与仔鱼消化系统为满足其迅速发育的营养需要而快速生长及鳔的发育有关。结果表明,鮸鱼在早期发育阶段优先发育对生长生存起关键作用的器官,即运动、视觉和摄食器官。但在稚鱼阶段,其主要长度量度相对于体长指标均呈现负异速成长。
Early ontogenesis of croaker Miichthys miiuy was studied in morphology and morphometrics. The croaker was reared at 24℃ from hatching to 53 days after hatching (dah). The larval stage was from hatching (2.02mm, total length) to metamorphism (36dah, 17.12mm total length), and onwards to metamorphism termination as the juvenile stage (53dah, 32.20mm total length). Compared to those in the juvenile stage, the larval stage featured stronger morphogenesis and differentiation with the replacement of embryonic adaptations and functions, such as respiration, exogenous feeding, and active swimming; head and tail grew faster than trunk, which shows that the feeding and swimming system developed in priority. Positive allometric growth of head (inflexion point at 9.80mm) was prepared for feeding and respiration, and correlated with positive allometric growth in eye diameter and mouth gape. The positively allometric inflexion point of tail growth, which is to reduce the energy cost of swimming and escaping from predators, was at 16.40mm. Although the trunk length increased slowly in early development, body height was positively allometric in growth (inflexion point at 11.20mm) for the development of digestive system satisfying nutritional needs of rapid growth. Therefore, in the early development, needs in basic functions of movement, vision, and feeding are met first, and then other needs for further growth.