Prevalence of Paratuberculosis in Dairy Cattle in Ecuador

Abstract

Background: Mycobacterium avium subsp. paratuberculosis (MAP) is the causal agent of paratuberculosis, a chronic infectious contagious disease of the intestinal tract of ruminants that are also associated with Crohn's disease in humans. The existence of paratuberculosis in Ecuador is virtually unknown; hence, the present study was performed to gain insight into the prevalence of this disease. Methods: Three dairy cattle farms in different geographic regions in Ecuador were investigated for the infection with MAP, and 600 blood samples, 200 of each cattle herd, were processed with an indirect enzyme-linked immunosorbent assay. Fecal samples of the seropositive cows were processed for culture on modified Löwenstein–Jensen medium. Results: One hundred and fifty bovines (25%) resulted seropositive and we confirmed with culture the presence of MAP in 4.7% (7/150) of the seropositive cows. Approximately 20% of the fecal samples of seropositive cows yielded nontuberculous mycobacteria (NTM) species including M. avium subsp. avium, a NTM species closely related to MAP. Conclusions: The seroprevalence of paratuberculosis in this first study for Ecuador is high (25%). We discuss a possible interference of NTM species, isolated from fecal samples, with the diagnosis of paratuberculosis. With this report, a baseline study, we confirm for the first time the presence of paratuberculosis in Ecuador, and we provide the necessary information for future studies and control of this disease.