FIG. 6.

Relative expression levels of SOD and GST mRNAs in adult F. hepatica (Fh) and F. gigantica (Fg) parasites isolated from Fasciola-infected ITT sheep. Ten ITT sheep were infected with 250 metacercariae of either F. gigantica or F. hepatica (five animals per group) for 12 weeks, and whole adult parasites were recovered from their livers. Parasites were washed with 1× PBS, incubated for 1 h at 37°C, and preserved in RNAlater (QIAGEN). Parasites from each group were combined, and 50 parasites of each Fasciola species were homogenized in Qiazol (QIAGEN). Relative mRNA expression levels were determined by real-time PCR. Significant differences (P < 0.01) in antioxidant defense enzyme mRNA levels between adult F. hepatica and F. gigantica parasites were calculated with the unpaired alternative t test.