Genetic Characterization of Captive South American Fur Seals in Japan Based on Mitochondrial and Microsatellite DNA Analyses

Molecular genetic analyses are effective in revealing the origin, kinship, and genetic diversity of zoo animals. In this study, we carried out the genetic characterization of captive founder individuals of the South American fur seal (Arctocephalus australis) in Japanese zoos and aquariums based on analyses of mitochondrial sequences and nuclear microsatellite loci. In mitochondrial DNA analysis, the haplotype diversity and nucleotide diversity of the overall population were 0.8949 and 0.0119, respectively. Microsatellite DNA analysis revealed that the observed heterozygosity within the overall population was 0.722. In addition, we did not detect genetic bottlenecks. The results from two kinds of DNA analyses indicated that the genetic diversity in this captive population was equivalent to that previously reported in wild populations. The detected mitochondrial haplotypes were the same as or phylogenetically close to those previously reported in wild populations in southern Brazil, Uruguay, Argentina, and southern Chile but diverged from those previously reported in a wild population in Peru. Genetic clustering analyses using microsatellite genotypes revealed that no clear genetic structures in this captive population.