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1.性早熟原因①投喂的饵料过精,特别是动物性饵料过多,再加培育池中天然饵料丰富,使生性贪食的河蟹加快发育生长,促进性早熟。②有效积温增加,促使了性腺发育。特别是在池塘、稻田培育蟹种时,由于水体较小,水层浅,水温回升快,加上培育蟹种一般在夏秋高温季节,水温一直较高,加速了蟹种的生长发育和性腺发育。③天然蟹苗一般为6月上旬发苗,而人工繁殖苗在3月初即可出苗,生长期比天然苗延长2.5～3个月,加上塑料大棚的强化培育,使蟹种
1 causes of precocious puberty ① feed fed too much, especially animal feed too much, plus natural enrichment ponds, so that the raw bulimia crab accelerate development and growth, promote precocious puberty. ② effective accumulated temperature, prompting the gonadal development. Especially in ponds and paddy fields, due to the small body of water, the shallow water layer and the rapid rise of water temperature in the ponds and paddy fields, the water temperature is always high in summer and autumn in high-temperature season, which accelerates the growth and gonadal development of the crab species . ③ natural crab seedlings in early June is generally the hair, and artificial breeding seedlings in early March to germination, growth of 2.5 to 3 months longer than the natural seedlings, coupled with the strengthening of plastic greenhouse cultivation, so that crab species