蛇鮈人工繁殖试验及其仔鱼异速生长模式的研究

2014-2016年在湖北省黄冈市赤东湖渔场对210尾湖泊野生蛇鮈(Saurogobio dabryi Bleeker)进行了人工繁殖试验,并对0~20日龄仔鱼的异速生长模式进行研究。结果显示:注射绒毛膜促性腺激素(HCG)、促黄体素释放激素类似物(LRH-A_2)和马来酸地欧酮(DOM)可促使成熟的雌性亲鱼产卵。产卵量为38.96万粒,孵出鱼苗13.5万尾,平均催产率、平均受精率、平均孵化率分别为75.0%、64.85%、55.15%。蛇鮈仔鱼的许多关键器官均存在异速生长现象。全长生长分为2个阶段,由慢速生长到快速生长的转折点为10日龄。头长、尾长、吻长均表现为正异速生长,而躯干长、胸鳍长表现为负异速生长。眼径的生长在4日龄时出现拐点,由等速生长转变为负异速生长。

Researches on artificial propagation breeding and allometric pattern in Saurogobio dabryi Bleeker

The artificial propagation breeding of Chinese lizard gudgeon(Saurogobio dabryi Bleeker)captured from Chidong Lake was conducted in Huanggang, Hubei province from 2014 to 2016.The allometric pattern of 0-20 days larvae fish was researched minultaneously.The results indicated that the female brooders which were induced to sexual maturity could spawn easily by injecting artificial synthetic hormone mixture consisting of chorionic gonadotropin(HCG), luteinizing hor-mone release hormone analogue 2(LHRH-A2) and dioxone maleate(DOM).The number of fertilized eggs was about 380 000 and the hatched larvae from that was about 135 000.The average spawning rate, average fertilization rate and average hatching rate was 75.0%, 64.85% and 55.15%, respectively.Most critical organs of larvae fish showed allometric phe-nomenon.The total length growth rate of larvae changed from slow to fast at the inflexion point of 10 days posthatch-ing.Allometrically positive growth of cephalic segment, tail length and snout length were found throughout the interval of this study, while a negative growth coefficient was shown in trunk length and pectoral fin length.The growth of eye diameter experienced a isometric growth until the inflexion point at 4 days posthatching, and thereafter it turned to be allometrically negative growth.