Relationship between gastrointestinal nematode burden, blood parameters and hair cortisol in Italian local sheep not treated with anthelmintics

This study explored the interplay between gastrointestinal nematode burden, blood parameters, and hair cortisol in Zerasca sheep, a local breed of Northeastern Tuscany (Italy). Moreover, the correlation between BCS and Eggs per Gram (EPG) was analyzed to verify the possible parasite impact. The study involved twelve ewes sampled for faeces, blood and wool three times, in the morning, from August 2022 to March 2023. Complete blood count, alanina-aminotransferase, aspartate-aminotransferase, nitrogen ureic, beta-hydroxybutyric acid, non-esterified fatty acids, total proteins, creatinine, calcium, chloride, potassium, and oxygen free radicals were analyzed. Fresh faecal samples were collected and subjected to the Mac Master technique for EPG. Wool was collected to quantify hair cortisol. BCS was recorded using a 1-5 scale. The ANOVA test was performed to detect differences in metabolic and immunological parameters, as well as hair cortisol levels, in relation to EPG levels. Non parametric correlation between EPG and BCS was conducted. Only red blood cells, haematocrit, mean corpuscular haemoglobin concentration, and calcium were significantly associated with EPG levels. Some parameters were outside the normal range. The correlation between BCS and EPG resulted negative and statistically significant. These results showed an overall well-being of the tested animals within this specific context.