REGULAR ARTICLES Prevalence and spectrum of Johne’ s disease lesions in cattle slaughtered at two abattoirs in Kampala, Uganda Julius Boniface Okuni & Manfred Reinacher & Panayiotis Loukopoulos & Lonzy Ojok Accepted: 18 December 2012 / Published online: 30 December 2012 # Springer Science+Business Media Dordrecht 2012 Abstract This study was conducted to determine the prev- alence and characteristics of Johne’ s disease (JD) lesions in Ugandan cattle slaughtered at two of the main abattoirs in Kampala. Ileocaecal junction and the associated lymph nodes of 1,022 cattle were examined for gross and micro- scopic lesions, followed by Ziehl Neelsen staining of the tissues bearing lesions. Confirmation of Mycobacterium avium subsp. paratuberculosis infection was done in some of the tissues using culture and IS900 PCR. The lesions were then described, characterised and tabulated. Characteristic Johne’ s disease granulomas were found in 4.7% of the samples examined, derived from Zebu, Ankole longhorn, Friesian breeds of cattle and their crosses. Lesions were found both in the lymph nodes and ileocaecal junction mucosa. The lesions tended to be more severe in the lymph node than in the mucosa. There were also some unique and atypical lesions found in association with Johne’s disease granulomas. The diagnostic values of various gross lesions and criteria of lesion classifications and diagnosis are revisited and discussed based on the findings of this study. The prevalence of Johne’ s disease lesions among slaughtered cattle in Kampala’ s two abattoirs indicates that the disease is well established in the cattle population in the country. The diverse manifestations in lesions of JD need to be considered when making histolog- ical diagnosis in tissues where the disease is suspected. Keywords Johne’ s disease . Paratuberculosis . Pathology . Cattle . Uganda Introduction Johne’ s disease (JD) or paratuberculosis, is a chronic wast- ing disease that affects a wide range of domestic and wild animals (Lombard 2011). The aetiology of the disease is an acid-fast bacterium called Mycobacterium avium subspecies paratuberculosis (MAP) (Tortoli 2003). It has serious neg- ative impact on the productivity of the affected animals (Vázquez et al. 2012). The control and eradication of the disease is constrained by the lack of diagnostic tools that can detect the infection at an early stage (Lombard 2011). Identification of the affected animals can be based on clin- ical signs, demonstration of the organism in faeces and tissues of affected animals using various bacteriological and molecular methods; serological testing in live animals, as well as gross and microscopic lesions in necropsy speci- mens (Gelberg 2007). In countries where JD has never been reported or where the disease has very low prevalence, facilities for culture and molecular diagnosis of the disease might not be in existence. Under such circumstances, path- ological diagnosis is very important. Although gross lesions can lead to a correct diagnosis of the disease in advanced stages, in some cases, even animals with advanced disease may lack such lesions. Moreover, in J. B. Okuni (*) : L. Ojok College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda e-mail: jbok@vetmed.mak.ac.ug M. Reinacher Institute for Veterinary Pathology, Justus-Liebig-Universitaet Giessen, Frankfurter Strasse 96, 35392 Giessen, Germany P. Loukopoulos Faculty of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece P. Loukopoulos California Animal Health and Food Safety Lab, School of Veterinary Medicine, University of California Davis, 105 W Central Ave, San Bernardino, CA 92408, USA Trop Anim Health Prod (2013) 45:1197–1202 DOI 10.1007/s11250-012-0346-3