基于微卫星标记对长江中上游胭脂鱼增殖放流效果的评估

摘要

Chinese sucker, Myxocyprinus asiaticus (Bleeker), is a freshwater fish that is endemic to China, and the only representative of the Catostomidae in Asia. Historically, M. asiaticus were primarily distributed in the Yangtze and Min-jiang (Fujian Province) rivers. Currently, the only remaining wild population is in the Yangtze River, primarily in the middle and upper reaches. The species was listed as a class Ⅱ state protected species by the Chinese government in 1988 and as a vulnerable species (VU) by the International Union for Conservation of Nature in 1998. Currently, hatch-ery-reared juvenile M. asiaticus are released into natural river systems to supplement the wild population in the Yangtze River. However, the effectiveness of these enhancement efforts has not be evaluated to date. To address this, we col-lected 149 breeding parents and 65 recaptured individuals, and evaluated the parentage relationship using 11 polymor-phic microsatellite loci. A total of 140 alleles were obtained and the mean observed and expected heterozygosity was 0.771 and 0.759, respectively. The range of the non-exclusion probability was 0.356-0.890 and the combined non-exclusion probability (first parent) of 11 loci was 99.998 3%. Eleven of the 65 recaptured individuals were off-spring of the breeding parents (4 from 26 samples in 2011, 3 from 16 samples in 2012, 4 from 23 samples in 2013). Our results suggest that the total contribution of the enhancement to the wild population of M. asiaticus was 16.92%in the middle and upper reaches of Yangtze River.%利用已经发表的11对胭脂鱼多态性微卫星标记,对长江中上游胭脂鱼(Myxocyprinus asiaticus)增殖放流效果进行评估。结果表明,5个胭脂鱼养殖场内所有的149尾繁殖亲本和长江中上游采集的65尾胭脂鱼中共观测到140个等位基因,其观测杂合度和期望杂合度的平均值(范围)分别为0.771(0.519~0.906)和0.759(0.469~0.894),多态信息含量(范围)为0.726(0.392~0.882)。通过软件Cervus统计得到,11个微卫星座位累计排除率为99.9983%,并且在长江中上游采集的65个样本中,11个样本与养殖场内繁殖亲本确定存在亲子关系,据此确定这11尾为增殖放流的胭脂鱼,并由此推算增殖放流的胭脂鱼对长江中上游野生群体的贡献量为16.92%。研究结果表明,增殖放流是实现胭脂鱼野生种群资源恢复的有效途径。