The genetic variation of muskrat (Ondatra zibethicus) in Lithuania

Abstract

The muskrat species Ondatra zibethicus homeland is North America but they were released in several rivers in Lithuania since 1954. The muskrats spread almost all over the country after acclimatization and today are subsumed as the invasive species in Lithuania. In different years the number of muskrats were very varied from 40 000 to 1000 individuals. The declining population number of muskrat is one of the factors related to accelerated inbreeding and loss of genetic diversity. The aim of this study was the examination of genetic variability of invasion species muskrat and bioinvasion situation in Lithuania. The population samples of muskrat were collected from eight regions of Lithuania. The genetic variation of the muskrat populations were analysed by microsatellites. Acording to Laurence et al. (2009) 12 microsatellites primers (Oz06, Oz08, Oz16, Oz17, Oz22, Oz27, Oz30, Oz32, Oz34, Oz41, Oz43, Oz44) were used in this study. But 9 of these 12 microsatellite loci were used in subsequent analyses in case 3 of them (Oz34, Oz27, Oz32) were not informative. The number of polymorphic loci is 76 % and size ranged from 134 to 291 base pairs. The genetic diversity among muskrat individuals ranging from 0.14 to 0.68. Standard diversity indices, deviation from Hardy- Weinberg, the inbreeding level and tests for genetic bottlenecks were applied in this study. These markers will be useful for further studies and which will give more details about the genetic structure of population in muskrat. The impact of muskrats on native species and communities (C0-C2) were analysed.