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冬季是各种养殖水域捕捞成鱼的季节,也是选择亲鱼的大好时机,选择亲鱼一般要考虑以下七个条件: 一、年龄:雌亲鱼达性成熟的年龄的个体,一般是指第一次产卵时的年龄,目前长江中下游各地的鱼类性成熟年龄是;白鲢3～4年;鳙鱼4～5年;草鱼5～6年;青鱼6～7年;鲤鱼2年;鲫鱼1年。雄鱼一般较雌鱼早一年成熟。二、体重:雌性鱼类达到第一次性成熟的体重,一般白鲢4～8公斤;鳙鱼8～12公斤;草鱼6～10公斤;青鱼12～16公斤;鲤鱼1公斤以上;鲫鱼0.2公斤以上。雄性鱼类体重一般略小于雌性鱼类。三、雌雄亲鱼的比例:一般雌鱼不得少于雄
Winter is the season of all kinds of aquaculture fishing into the fish, but also a good time to choose the broodstock, select the broodstock generally have to consider the following seven conditions: First, the age: Female fish up to sexual maturity of the individual, generally refers to the first production Eggs age, the current maturity age of fish around the middle and lower reaches of the Yangtze River is; silver carp 3 to 4 years; catfish 4 to 5 years; grass carp 5 to 6 years; black carp 6 to 7 years; carp 2 years; carp 1 year. The males generally mature a year earlier than the female. Second, the weight: female fish to achieve the first sexual maturity of the body, the general silver carp 4 to 8 kg; catfish 8 to 12 kg; grass carp 6 to 10 kg; 12 to 16 kg of black carp; carp more than 1 kg; carp 0.2 Kg or more. Male fish generally weigh slightly less than female fish. Third, the proportion of male and female broodstock: general females should not be less than male