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在鱼类繁殖期间,会发生各种病害,甚至使全部鱼苗毁灭,造成严重的损失。现将病因、病原生物和防治方法介绍如下。 (一)产后亲鱼的死亡 亲鱼是进行繁殖的基础。如果亲鱼经过催情产卵之后死亡,必将对今后的繁殖造成不良后果。出现产后亲鱼死亡的原因:主要是操作粗糙,亲鱼严重受伤并感染了细菌或真菌,引起并发性鱼病,鱼体衰弱,抵抗力降低所致;第二是由于亲鱼培育不佳,性腺发育不良,成熟度不好,而强行催产,发生难产而引起;第三是催产剂用量过大或不当,亲鱼无法适应和忍受所造成。为减少或防止亲鱼产后死亡,在催产过程中,必须注意以下几点:
During fish breeding, various diseases occur, and even all the fry are destroyed, resulting in serious losses. The etiology, pathogens and prevention methods are described below. (A) the death of broodstock broodstock is the basis for breeding. If the broodstock dies after aphrodisiac spawning, it will surely have adverse consequences for future breeding. Causes of postpartum broodstock death: mainly rough operation, the broodstock seriously injured and infected with bacteria or fungi, causing concomitant fish diseases, fish body weakness, reduced resistance caused by the second is due to broodstock poor cultivation, gonadal dysplasia , Maturity is not good, and forced oxytocin, caused by dystocia; the third is the amount of oxytocin is too large or inappropriate, the broodstock can not adapt and endure the result. In order to reduce or prevent the death of broodstock, we must pay attention to the following points during the process of oxytocin: