广东鲂的胚后发育

2007年6~7月,在西江肇庆江段收集广东鲂(Megalobrama hoffmanni)亲鱼,通过人工催产、干法授精获得受精卵。随后对其胚后发育进行连续观察,拍照并详细描述各发育期形态。广东鲂胚后发育的主要特征是:身体较为透明,头部背面色素最多时达7~8个;听囊前后色素蔓延成明显的色素花;腹部前端逐渐形成葫芦状的色素花纹,该花纹在腹鳍芽出现后逐步淡化、消失;尾长占全长的比例较大,从孵出期时的31%逐渐增加到臀鳍形成期时的46%;鳔一室期后,鱼苗身体肌节数为43对左右,其中尾部肌节数19对以上。经过24d的生长和发育,鱼苗各鳍条基本形成,形态与成鱼相似。

Post-embryonic Development of Megalobrama hoffmanni

The successive observation was conducted to study the artificial fertilized embryos and fry of Megalobrama hoffmanni from June to July in 2007. The post-embryonic development were divided into 12 stages based on the external morphology, internal morphogenesis; each stage were described and photographed. The characteristics of M. hoffmanni is very obvious: The body is somewhere transparent, with few pigments on the head; Beside the otic capsule there are some pigments developing into pigment flower; The shape of pigments in the fore part of belly likes a Calabash Gourd, which fades gradually after the formation of ventral fin; The length of caudal is 31% to 46% of the total length; After one chamber air bladder stage, total muscle nodes are about 43 pairs, including more than 19 pairs muscle nodes in the caudal. After developing and growing for 24 days, with formation of all fins, the fry gets the same characters as the adult M. hoffmanni.