采用耳石、鳞片、匙骨和鳃盖骨等4种年龄鉴定材料对云南滇池红鳍原鲌的年龄鉴定结果进行比较,以吻合率、可判读力和平均变异系数为依据确定最佳年龄鉴定材料.红鳍原鲌的微耳石轮纹清晰,在解剖镜入射光下呈现明暗相间的条纹,无明显杂纹,年轮标志清晰;而鳞片轮纹在4龄以上时年轮特征不清晰,读龄过程中易被忽略;此外,高龄个体匙骨和鳃盖骨分别出现中心部分透明、基部较厚等原因,造成年龄低估.判读结果表明,微耳石和鳞片的吻合率及平均变异系数均优于匙骨和鳃盖骨.因此,以微耳石年龄读数为基准,并与鳞片、匙骨和鳃盖骨进行对比.结果显示,鳞片与其吻合率最高,为92.7%,平均变异系数最小为1.9%,匙骨和鳃盖骨与其吻合率分别为77.2%和61.3%,平均变异系数分别为9.3%和12.6%.综合分析认为,耳石为滇池红鳍原鲌最佳年龄鉴定材料,鳞片因具有采集方便不伤鱼体的优点,也是很好的年龄鉴定材料,匙骨和鳃盖骨则不适于滇池红鳍原鲌的年龄鉴定.%The morphology and annulus characteristics of redfin culter Cultrichthys erythropterus were described by four aging materials (otolith, scale, cleithrum, and operculum) in Dianchi Lake in Yunnan, China, and then the suitable aging materials were determined in terms of interpretability agreement and CV(Coefficient of Variation).The annulus was showed clearly by alternative stripes on the otolith under the dissecting microscope, while scales was not showed clearly above 4 years old fish, leading to underestimated in aging.In addition, age underestimation also appeared in cleithrum and operculum.Among the four materials, the maximal percentage of agreement values between two age reading results was the lapillus (98.2%, n=221), followed by scale (91.7%, n=218), cleithrum (66.5%, n=215) and operculum (59.8%, n=199).The lapillus showed the minimal average coefficient of variation(0.5%), followed by scale (2.1%), cleithrum (10.7%) and operculum (13.4%).Comparing with the lapillus, the agreement was 92.7% for scales, 77.2% for cleithrum, and 61.3% for operculum, and the average coefficient of variation was 1.9% for scales, 9.3% for cleithrum, and 12.6% for operculum.Therefore, the lapillus and the scales were the suitable age determination materials, while cleithrum and operculum were not useful materials for determining age of redfin culter in Dianchi Lake.
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