Epidemiological and Biomolecular Updates on Encephalitozoon cuniculi in Lagomorpha of Sardinia (Italy)

A survey was carried out to determine the prevalence of Encephalitozoon spp. in lagomorphs of Sardinia (Italy) at nine industrial rabbit farms (Oryctogalus cuniculus) and in two breedings of hares (Lepus capensis mediterraneus). A total of 378 slaughtered rabbits (meat rabbits and breeders) and 45 living hares were examined. The survey was carried out including three different approaches: serological, pathological, and biomolecular. Sera obtained after centrifugation were frozen at −18°C until examination by carbon immunoassay (Medicago, Uppsala, Sweden). Six out of the nine rabbit farms were found to be serologically positive for E. cuniculi (66.7%), while the number of seropositive rabbits was 68 of 378 (18.5%). All hare sera tested negative. In all slaughtered rabbits, macroscopic renal lesions, presumably attributable to infection with E. cuniculi, were detected. Gross lesions were found in 62 out of the 378 individuals examined (16.4%). DNA was extracted from 22 samples that were positive for microsporidia and subjected to sequencing and genotyping. All isolates investigated showed 100% homology to E. cuniculi.