金钱鱼(Scatophagus argus)是一种具有观赏和食用价值的名贵海水经济鱼类, 环境适应性和抗病抗逆性极强。本文首次较系统研究了金钱鱼养殖群体的繁殖生物学特性和人工诱导产卵技术。结果表明: 金钱鱼雌雄性比为1.31: 1, 雌、雄鱼最小生殖生物学年龄均为1龄; 2龄以上亲鱼生殖机能较健全, 适合人工繁殖。4—8月是南方沿海金钱鱼的生殖期, 盛期为5—7月。雌鱼个体绝对生殖力F为337309—635755粒, 平均456320粒, 个体相对生殖力(F/W, W体重)为720.4—963.3粒•g−1, 平均843.1粒•g−1; 金钱鱼性腺雌雄异体, 雌鱼性腺成熟系数(gonadosomatic index, GSI)最高达14.7%, 雄鱼GSI最高2.2%, 为多次性产卵类型。金钱鱼能在淡水或低盐海水中正常生长发育, 但需要在较高的盐度中生殖, 在环境适宜条件下, 性成熟的雌鱼经过混合激素的诱导[1.每千克体重15µg的LHRH-A2(促黄体素释放激素类似物, Luteinzing Hormone Releasing Hormone-analogue)+每千克体重3.0—4.0mg 的DOM(地欧酮Domperidone); 或2.每千克体重15µg 的LHRH-A2 +每千克体重1000—1500Iu的HCG (人体绒毛膜促性腺激素, Human Chorionic Gonadotropin, HCG)] 能自然产卵和受精, 月相盈亏和潮汐变动对金钱鱼的人工诱导产卵结果没有明显影响。金钱鱼产浮性卵, 单油球, 卵子直径750µm左右, 受精卵每克约3500—3800粒, 在水温27—29℃, 盐度25‰条件下, 胚胎经过20—24h发育, 孵化出仔鱼。刚出膜的仔鱼全长1.75—1.88mm, 4日龄仔鱼全长2.6—2.8mm, 卵黄囊消失, 开始摄食浮游动物幼体, 仔鱼处于内、外源营养转变期。研究工作为深入开展金钱鱼生殖调控和产业化种苗繁育技术开发研究提供繁殖生物学基础资料和实用技术。

Scatophagus argus is a highly commercially valuable fish, which is strongly resistant to environmental stress. In this study, the authors focus on the reproductive biological feature and general growth activity of cultured Scatophagus argus using experiments of artificial induction of spawning. The results indicate that the sex ratio of male to female Scatophagus argus is 1:1.31. The minimum biological age of reproduction is 1 for both female and male. Two-year-old parent fish adapts quickly to artificial breeding. The period from April to August is the reproductive season for Scatophagus argus in South China coastal waters. The peak of spawning season is between May and July. The absolute fecundity of individual female is 337309 to 635755 in number, with an average of 456320. The relative fecundity of individual is 720.4 to 963.3 per gram in number and 843.1 on average. Scatophagus argus is dioecious. The GSI (gonadosomatic index) of female fish is up to 14.74% while that of male is up to 2.2%. It is necessary for this fish to spawn in water of higher salinity. The fish is capable of multiple spawning during its reproductive period. Under appropriate circumstances, sexually mature female fish is able to spawn by the induction of mixed hormone [15µg•kg−1 LHRH-A2 (Luteinzing Hormone Releasing Hormone-analogue) +3.0−4.0mg•kg−1 DOM (Domperidone) or 15µg•kg−1 LHRH-A2 +1000−1500Iu•kg−1HCG (Human Chorionic Gonadotropin)] and fertilize naturally in captivity. The phases of the moon and the tides do not influence the induction of Scatophagus argus spawning apparently. Scatophagus argus spawns pelagic eggs with single oil globules. The diameter of its eggs is about 750 µm. The number of its oosperms per gram is about 3500 to 3800. The development of embryos takes 20−24 h to hatch larvae at the water temperature of 27−29℃ and salinity 25‰. The length of newly hatched larvae is 1.75 to 1.88 mm. The length of four-day-old larvae, yolk sacs of which have disappeared, is 2.6 to 2.8 mm. Then the baby fish starts to feed on plankton larvae, and soon turns into nutritional transition period.