Relationships between Oxidative Stress, Liver, and Erythrocyte Injury, Trace Elements and Parasite Burden in Sheep Naturally Infected with Dicrocoelium dendriticum

Background: The aim of this study was to investigate the role of oxidative stress in the pathology of ovine dicrocoeliasis.

Methods: During Dec 2013 - Oct 2014, seventy-two sheep (1-3 years) with liver dicrocoeliasis along with 47 healthy sheep were selected from animals admitted for slaughtering at slaughterhouse located in Neyshabour, Razavi Khorasan Province, Iran.

Results: In comparison to healthy control, the malondialdehyde (MDA) level and serum total antioxidant capacity were significantly higher in the parasitized group (P<0.05). A significant increase in liver MDA concentration (P<0.05) of parasitized group was also observed. Packed cell volume (PCV), zinc, iron, total bilirubin and albumin sera levels were significantly lower in the parasitized group (P<0.05). In parasitized sheep, a significant positive correlation was seen between serum MDA concentration and the activity of aspartate aminotransferase (AST). On the other hand, the concentration of serum MDA was inversely correlated with the value of PCV. No significant differences were observed for MDA concentration and total antioxidant capacity between normal and abnormal hepatic lobes in the parasitized animals. Oxidative stress markers (MDA and total antioxidant capacity in serum and liver samples) showed no significant correlations with the extent of pathological lesions and serum variables of liver injury in the parasitized sheep. No significant correlation was observed between oxidative stress markers and the fluke's number in the parasitized animals.

Conclusion: Oxidative stress may play an important role in the erythrocyte destruction in sheep naturally infected with D. dendriticum. However, no clear relationships were observed between the oxidative stress, hepatic damage and parasite burden.