Genetic diversity of the sika deer (Cervus nippon) in Lithuania

Abstract

Sika deer (Cervus nippon) is considered to be an invasive species in Europe. The main problem that the European free-living sika deer pose is damage to forests as well as hybridisation with the local red deer (Cervus elaphus). The aim of this study was to analyse the genetic diversity of the sika deer and the red deer in Lithuania. 30 individuals of sika deer from enclosures and 33 hunted free-ranging red deer were studied by using tissue samples. Genotyping was based on seven microsatellites loci (STR) of nuclear DNA. The STR loci were variable, with 1 to 17 alleles and higher than intermediate values of heterozygosity (sika deer: Ho = 0.695, He = 0.694; red deer: Ho = 0.626, He = 0.624). Inbreeding coefficient (Fis) and probability of significant deviation from Hardy-Weinberg equilibrium (P) ranged between -0.229 and 0.205 (mean = - 0.025, SE = 0.093). The PCoA analysis showed that the sika deer samples differed from the red deer samples; however, two red deer individuals from the free-ranging population (harvested in Panevėžys and Ukmergė regions) which mixed with the individuals of the sika deer were identified. According to the phenotype, these animals were attributed to the red deer; however, according to a fixed genotype, they were closer to the sika deer. Moreover, three sika deer individuals mixed in a 2D space with the red deer individuals. Therefore, it can be concluded that population of free- ranging red deer in Lithuania contains also the hybrids between the red deer and the sika deer.