Study on prevalence and associated risk factors of epizootic lymphangitis in equine in Nagele Arsi town, southeastern Ethiopia.

Epizootic lymphangitis is a contagious, chronic and overwhelming disease of equids, characterized by chronic discharging skin nodules. This study was aimed to investigate the prevalence and associated risk factors of epizootic lymphangitis in equines at Nagele Arsi town, southeastern Ethiopia. A cross-sectional study using a random sampling technique was employed from December 2021 to June 2022 via clinical and microscopic examinations of the lesions. The overall prevalence of epizootic lymphangitis was 4.37% with a prevalence of 6.69%, 0.72%, and 0% in horses, donkeys, and mules, respectively. The sex, species, harness type, season, and body condition scores of equids have shown statistically significant differences (p < 0.05) with the prevalence of epizootic lymphangitis. Macroscopically, the lesions revealed varying degrees of nodule to ulcer on the sternum, limbs, face, and cervical region of the equine. Upon giemsa stain, fungal hyphae with a halo (unstained capsule-like) structure were observed. Histologically, pyogranulomatous inflammation with fibroplasia was appreciated. In conclusion, epizootic lymphangitis was rampant in the study area. This requires a detailed investigation incorporating a large sample size using fungal culture and other molecular techniques including PCR.