GENETIC DIVERSITY IN PORCINE OESOPHAGOSTOMUM-DENTATUM AND OESOPHAGOSTOMUM-QUADRISPINULATUM AND THEIR DELINEATION BY ISOENZYME ANALYSIS

The genetic diversity in eight strains of Oesophagostomum dentatum and O. quadrispinulatum was investigated by the electrophoresis study of ten enzyme systems. The loci Idh-2, Fbp, Sdh, and Pgm were found to be diagnostic between the species examined. Both the proportion of fixed allelic differences (26.3%) and the genetic distance coefficient (D = 0.54) are well above the range for differentiation of valid species, Isoenzyme patterns of susceptible and resistant lines of O. dentatum s howed at polymorphic loci a reduced genetic heterogeneity in the latte r group. No qualitative difference in terms of the presence/absence of alleles was observed among susceptible and resistant isolates with th e enzymes studied. The detection of one possible hybrid indicates that introgression in O. dentatum and O. quadrispinuatum may occur.