头骨形态指标鉴别水貂来源有效性的评估

Assessment of the Effectiveness of Skull Morphometric Indices for Discrimination of Wild and Farmed American Mink

人工驯养野生动物是获取野生动物产品的重要手段,但是非法盗猎的野生动物产品以人工饲养的名义进入市场,就会对野生动物的保护形成挑战。因此,准确鉴别市场上的动物产品是来自养殖场还是野外,是保护野外种群,维持养殖业正常秩序的关键。本研究以北美水貂(Neovison vison)为例,基于颧骨内侧空间(ZAS)、颧宽(ZAA和ZBA)、颅基长(BSL)、下颌长(MDL)、眶后收缩(POC)和最大面部宽度(GFB)等量度,建立了9个头骨形态计量学指标:POC/GFB、POC/BSL、POC/MDL、ZAS SQRT/BSL、ZA SSQRT/MDL、ZBA×BSL/2ZAS、ZBA×MDL/2ZAS、ZBB×BSL/2ZAS和ZBB×MDL/2ZAS。野生组(n=32,9雄23雌)和饲养组(n=45,35雄10雌)的比较表明,除POC/GFB外,所有指标对于在两组样品之间均有显著差异,整体判别正确率为73.2%—85.5%。在性别已知的情况下,雄性的整体正确率为82.4%—93.8%,雌性为41.7%—85.7%。为此,应针对不同性别、不同来源的动物建立相应的参考数据,利用似然比进行鉴别。本研究的结果不仅可用于北美水貂的鉴别,也为其他小型食肉动物的鉴别提供经验。

Captive rearing of wild animals is an important means of obtaining wild animal products.But products from poached wild animals can enter the market if fraudulently labeled as products of captive breeding.This poses a challenge to the protection of wild animals.Accurately identifying whether traded animal products are derived from the farm or the wild is key to protecting wild populations and maintaining the legality of the breeding industry.Taking the American mink(Neovison vison)as a model for small carnivores,we measured zygomatic arch space(ZAS),zygomatic breadth(ZAA and ZBA),basal length(BSL),mandible length(MDL),postorbital constriction(POC),greatest upper facial breadth(GFB),and other parameters to establish 9 skull morphometric indicators,namely POC/GFB,POC/BSL,POC/MDL,ZAS SQRT/BSL,ZAS SQRT/MDL,ZBA×BSL/2ZAS,ZBA×MDL/2ZAS,ZBB×BSL/2ZAS,and ZBB×MDL/2ZAS.The comparison between wild American mink(n=32,9 males and 23 females)and farmed American mink(n=45,35 males and 10 females)showed that all indices proved effective with moderate overall discrimination correctness for samples of known origin(73.2%-85.5%).The single exception was POC/GFB.When the sex was known,overall correctness was 82.4 to 93.8%for males,but 41.7 to 85.7%for females.Therefore,corresponding reference data sets should be established for animals of different genders and different sources,and the likelihood ratio should be used for identification.This result is not only valid for North American mink,but also provides reference for the identification of the sources of other small carnivores.