Starvation and Determination of Point of No Return in Schizothorax prenanti Larvae
ZHANG Jianming
1. Institute of Chinese Sturgeon Research, China Three Gorges Project Corporation, Yichang 443100, China; 2. Hubei Key Laboratory of Three Gorges Project for Conservation of Fishes, Yichang 443100, China
Abstract：The same batch of newly hatched Schizothorax prenanti larvae were reared in a glass fiber tank (2.0 m × 0.8 m × 0.6 m) and 5 days later, one day before initial feeding, randomly divided into group A in which the 6 day old postlarvae were fed fairy shrimp (Artemia salina), group B and group C, both of which the postlarvae were fasten, at density of 500 larvae per tank at water temperature of 17.3—21.5 ℃ to investigate the effects of starvation on growth, development, survival, yolk sac absorption, food intake and feeding intensity of the larvae and to determine point of no return (PNR) (the age when the initial feeding rate of larvae was lower than 50% of the maximum initial feeding rate) for better understanding of recruitment and protection of the population of S. prenanti. The results showed that the starved larvae had significantly lower growth index of total length, body length, body height and body length before an anus and development of tissues and organs such as eye diameter and sputum of the larvae (P<0.01). The transitional period was found in 7 day old larvae of S. prenanti. The postlarvae had initial feeding rate of about 15%, the maximum value of 100% in 13 day and 14 day old larvae, and the 17-day-old larvae had the PNR. The cumulative mortality of 50% was observed in 19 day old larvae starved, after PNR. The findings indicated that the S. prenanti larvae had strong hunger tolerance, and the best feeding time at 9 days old, and the latest initial feeding within 15 days old.
张建明. 齐口裂腹鱼仔鱼饥饿试验及不可逆生长点的确定[J]. 水产科学, 2020, 39(4): 532-538.
ZHANG Jianming. Starvation and Determination of Point of No Return in Schizothorax prenanti Larvae. Fisheries Science, 2020, 39(4): 532-538.
2020, Vol. 39 
