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2011年4～5月,研究了温度对花斑副沙鳅(Parabotia fasciata)早期仔鱼的发育、初次摄食时间、群体摄食率及不可逆点(PNR)的影响。结果发现,花斑副沙鳅仔鱼出膜后2 d已开始摄食;初次群体摄食率最高值出现在卵黄囊耗尽后的1～2 d,花斑副沙鳅仔鱼的摄食强度随温度升高而增大。仔鱼抵达PNR的时间随温度升高而缩短:22℃时,仔鱼的PNR出现在出膜后的8.0～9.0 d;26℃时,PNR为7.0 d;28℃时,PNR为5.5 d;30℃时,PNR为5.0 d。最大初次摄食率至PNR之间为不可逆饥饿期,22℃时为3.5 d,30℃时仅为1.5 d,说明温度越高,仔鱼耐受饥饿的能力越差,越不利于仔鱼的存活。研究认为,温度对花斑副沙鳅仔鱼发育、摄食及不可逆点的影响较大;在苗种培育过程中,应根据温度确定投饵时间,适时投饵对仔鱼的成活显得尤其重要。
From April to May in 2011, the effects of temperature on the development, initial feeding time, feeding rate and irreversible point (PNR) of early larvae of Parabotia fasciata were studied. The results showed that the feeding of M. freudianus had begun to feed 2 days after emergence, the highest value of the initial feeding rate appeared 1 ~ 2 d after the yolk sac was depleted, and the feeding intensity of S. parvus larvae increased with increasing temperature Increase. The PNR of larvae shortened with increasing temperature. PNR of larvae reached 8.0-9.0 d after larvae formation at 22 ℃, PND was 7.0 d at 26 ℃, and PND was 5.5 d at 28 ℃. The PNR is 5.0 d. The maximum initial feeding rate to PNR is irreversible hunger period, 3.5 d at 22 ℃ and 1.5 d at 30 ℃, indicating that the higher the temperature, the poorer the ability of larvae to tolerate starvation, the less favorable to the survival of larvae. The results showed that temperature had a significant effect on the development, feeding and irreversibility of larvae of loach. In the course of cultivating seedlings, the feeding time should be determined according to the temperature. It is especially important for the survival of larvae to be fed on time.