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鲤鱼是黑龙江省池塘的主要养殖品种,约占放养量的50%~60%。但是,我省养殖的鲤鱼品种十分单一,主要以本省的野鲤和来自南方的鲤鱼为主。前者抗寒能力很强,适应本地的养殖条件,但单产较低,二年很难准养成0.5kg以上的商品鱼;后者虽然以杂交鲤身份出现,但实质是十分混杂的鲤鱼,并非是真正的杂种F_1,引入我省由于生长时间的加长,当年可培育成100~150g的鱼种,但其抗寒能力极低,很难在我省自然条件下过冬。据了解不少鱼种场的赿冬成活率为零,最高也不超过30%,原因是它们不适应这里的气候条件,极易感染嗜水气单胞菌,这种菌在生长季节呈隐性态,但进入越冬期则呈阳性状态,形成暴发性鱼病,造成越冬的南方鱼种大批死亡。这种病的具体表现为体表检查正常,也无寄生虫感染,但剖开腹
Carp is a major aquaculture species in ponds in Heilongjiang Province, accounting for about 50% to 60% of stocking volume. However, carp species farmed in our province are very single, mainly dominated by the province’s wild carps and carp from the south. The former is very cold-resistant and adapts to local farming conditions. However, the yield per hectare is relatively low. It is difficult to produce fish products of more than 0.5kg in two years. Although the latter appears as a hybrid carp, it is not very common Is a true hybrid F_1, introduced into the province due to the growth of the longer, then can be cultivated into 100 ~ 150g of fish species, but its extremely cold hardiness, it is difficult to winter in our province under natural conditions. It is understood that many species of winter farm survival rate is zero, the highest nor more than 30%, because they do not adapt to the climatic conditions here, easily infected with Aeromonas hydrophila, the bacteria in the growing season was hidden However, when entering the wintering period, they became positive and formed an outbreak of fish disease, resulting in the death of a large number of wintering southern fish species. The specific manifestation of this disease is the normal body surface examination, nor parasitic infection, but cut open belly