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团头鲂原产于长江中游的一些大中型湖泊中,北京地区于20世纪90年代中期引进并大面积推广,取得了显著的经济效益和社会效益。然而,近年来该群体出现了严重的退化现象,具体表现为生长速度缓慢、抗病力下降、性成熟提早、体型变长变薄等,严重制约了养殖生产的发展。基于上述原因,2
Among the large and medium-sized lakes that originated in the middle reaches of the Yangtze River, the Beijing area was introduced and popularized extensively in the mid-1990s and achieved remarkable economic and social benefits. However, in recent years, the population has experienced serious degradation phenomenon, which is manifested in its slow growth rate, decreased disease resistance, earlier sexual maturity, thinner and longer body shape, which severely restricted the development of aquaculture production. For the above reasons, 2