Express method for determining the sex of fingerlings of mouse-like rodents (Rodentia: Cricetidae) without anatomization

Abstract

A new effective method for sex determination of immature mouse-like rodents of the hamster family has been used (Cricetidae Fischer, 1817) based on physical impact on the urinary perineal area. The 212 immature specimens of five rodent species was tested: Myodes rutilus Pallas, 1779, M. glareolus (Schreber, 1780), Alexandromys oeconomus Pallas, 1776, Agricola agrestis (Linnaeus, 1761), Myopus schisticolor (Lilljeborg, 1844). Verification of the new method was provided using a control dissection of the studied samples of rodent. The effectiveness of express method of sex determination for under yearling rodent was 88.5–100% among samples of studied species. The effectiveness of morphological characteristics (body weight and length, anogenital distance) was 76.2–93.5% in the sex identification and only for four studied species. The new method was more successful than morphometric methods in sex determination for studied samples of immature M. schisticolor and M. glareolus by 19% and 6.8%, respectively. The close results had been detected for both methods in sex determination of M. rutilus. For sex determination of immature specimens of A. agrestis the morphometric characteristics effectiveness was 4.6% higher compared to the new method. For studied samples of A. oeconomus only the new method of sex determination of an under yearling specimens was effective. The preference in choose of non-anatomical method of sex determination of immature specimens of Cricetidae family is directly depends on the species of study rodent. The new method can be used in studies with vital animals.