Evaluation of oxidant/antioxidant balance in Iberian ibex (Capra pyrenaica) experimentally infested with Sarcoptes scabiei

Abstract

Oxidative stress (OS) is an imbalance between radical-generating and radical scavenging activity, resulting in oxidation products and tissue damage. Although some studies have been done in other species, there is a lack of information about the oxidative/antioxidant status in the Iberian ibex (Capra pyrenaica) affected by sarcoptic mange. To clarify this fact, albumin, catalase (CAT), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), paraoxonase-1 (PON-1), glutathione reductase (GR), reduced glutathione (GSH): oxidized glutathione (GSSG) ratio, thiobarbituric acid reactive substances (TBARS) and total oxidant status (TOS) concentrations were measured in peripheral blood of ibexes experimentally infested with Sarcoptes scabiei (n=25), as well as in the healthy control group (n=14). During the course of the experiment, the infected ibexes were visually assigned to four categories according to the percentage of skin surface affected by mites. In the infested ibexes, the levels of albumin, PON-1, CAT, SOD, GSH-Px and GSH:GSSG ratio showed a significant (p<0.01) decrease with disease progression. With respect to the control group, this decrease was significantly (p<0.001) lower in the more severe clinical stages. No significant changes were observed in GR activity during disease or with respect to the control group. Conversely, the concentrations of TOS and TBARS increased with lesion severity, and with respect to the control group, this increase was significant (p<0.01) in the more advanced stages of the infection. Additionally, to explore the possible effects of sex, age, haplotype, mange status, and days post infection (dpi) on each of the OS biomarkers, generalized additive mixed models were applied. According to our results, the mange status and dpi explained the highest percentages in the observed changes in the biomarkers analyzed, whereas the haplotype only influenced the observed variability of albumin and TOS. The contribution of sex and age was not significant in any of the OS biomarkers. From the present study, it may be concluded that sarcoptic mange infestation increases OS and decreases antioxidant status in ibex. This imbalance may contribute to the pathogenesis of this disease.

Keywords: Capra pyrenaica; Ibex; Mange; Oxidant/antioxidant status; Oxidative stress; Sarcoptes scabiei.