Genetic variability among natural populations of the liver fluke Fascioloides magna in white-tailed deer, Odocoileus virginianus

Liver flukes, Fascioloides magna, from white-tailed deer were collected from four locations in the southeastern United States for genetic analysis of spatial differentiation. Nine of 14 electrophoretic loci were polymorphic. Average individual parasite heterozygosity ranged from 4.6 ± 3.4 to 13.1 ± 5.9%. These levels of genetic variability are comparable to those reported for other species of parasites. Allele frequency differences among samples were noted for seven of the nine polymorphic loci. Rogers genetic distance values for interlocality comparisons increased with geographic distance between samples. Partitioning the total genetic variation in Fascioloides magna, 83% of the variance was found among individuals within sample locations, 4% between locations within Tennessee and South Carolina, and 13% between states.