斑重唇鱼仔稚鱼发育特征和饥饿不可逆点研究

Developmental characteristics and point of no return of larval and juvenile Diptychus maculatus Steindachner under starvation

  • 摘要: 掌握斑重唇鱼 (Diptychus maculatus Steindachner) 的基础生物学特征与数据,推动其自然资源的恢复与可持续增长,是加强伊犁河流域珍稀濒危物种的保育研究的基础与前提。在水温12.2~13.4 ℃条件下,连续观察斑重唇鱼仔稚鱼的形态发育,记录其生长指标及特性;并采用试验生态学开展斑重唇鱼初孵仔鱼的饥饿试验,研究了饥饿胁迫下仔鱼的形态、生长、存活率及不可逆点。依据斑重唇鱼仔稚鱼发育特点,划分为早期仔鱼 0—14日龄 (Days post hatch, dph)、晚期仔鱼 (15—254 dph) 及稚鱼期 (255—592 dph);初孵仔鱼全长为 (10.30±0.05) mm,卵黄囊体积为 (12.96±0.51) mm3,11 dph仔鱼开口,14 dph仔鱼卵黄囊完全消失,255 dph仔鱼出现鳞片,进入稚鱼期,592 dph稚鱼鳞片完全包被,与成鱼形态相似,稚鱼期结束,进入幼鱼期;对照组仔鱼14 dph卵黄囊完全吸收,饥饿组仔鱼16 dph卵黄囊完全吸收,混合营养期3~5 d,容易遭受饥饿胁迫。仔鱼初次摄食发生在11 dph,摄食率仅为5%;16 dph初次摄食率为100%;PNR发生在23 dph。斑重唇鱼早期仔鱼期历时14 d,晚期仔鱼期历时240 d,稚鱼期历时338 d,破膜仔鱼592 dph后进入幼鱼期。研究数据可为斑重唇鱼早期发育研究提供参考,仔鱼可在11 dph开始少量投喂,最佳投喂时间为13 dph,但最晚投喂时间不宜超过19 dph。

     

    Abstract: Mastering the basic biological characteristics and relevant data of Diptychus maculatus Steindachner, and facilitating the restoration and sustainable development of its natural resources, constitute the essential foundation and prerequisite for carrying out conservation research on rare and endangered species in the Ili River Basin. Under water temperatures of 12.2–13.4 ℃, we continuously observed the morphological development of larvae and juvenile fish, and recorded the growth indicators and characteristics. Ecological experiments were conducted to induce starvation in newly hatched larvae, examining changes in morphology, growth, survival rate, and the point of no return (PNR) under starvation stress. Based on developmental characteristics, the early life stages were divided into three periods: the early larval stage (0−14 days post hatch, dph), the late larval stage (15−254 dph), and the juvenile stage (255−592 dph). Newly hatched larvae measured (10.30±0.05) mm in total length, with a yolk sac volume of (12.96±0.51) mm3. Larvae first fed at 11 dph, and the yolk sac was completely absorbed by 14 dph. Scales appeared at 255 dph, marking the transition to the juvenile stage. By 592 dph, the body was fully covered with scales, and the morphology resembled that of adult fish, signifying the end of the juvenile stage and the transition to the young fish stage. In the control group, the yolk sac was completely absorbed by 14 dph, while in the starvation group, absorption was completed by 16 dph. The mixed feeding period lasted 3–5 days, during which larvae were highly vulnerable to starvation stress. First feeding occurred at 11 dph, with a feeding rate of only 5%; the feeding rate reached 100% by 16 dph. The PNR occurred at 23 dph. The early larval stage of D. maculatus lasted 14 d, the late larval stage 240 d, and the juvenile stage 338 d. Post-larvae entered the young fish stage after 592 dph. These data provide a reference for studies on the early development of D. maculatus. Initial feeding can commence with small quantities at 11 dph, with 13 dph being optimal. However, feeding should commence no later than 19 dph.

     

/

返回文章
返回