Prevalence of tuberculous lesion in cattle slaughtered in Mubende district, Uganda.
BACKGROUND
The aim of this study was to estimate the prevalence of gross pathology suggestive of bovine tuberculosis (TB-like lesions) and evaluate animal's characteristics associated with the risk of having bovine TB-like lesions among cattle slaughtered in Mubende district in the Uganda cattle corridor.


METHODS
We conducted a cross sectional study in which 1,576 slaughtered cattle in Mubende district municipal abattoir underwent post-mortem inspection between August 2013 and January 2014. The presence of bovine TB-like lesions in addition to the animal's sex, age, breed, and sub-county of origin prior to slaughter were recorded. Associations between the presence of bovine TB-like lesions and animal's age, sex, breed, and sub-county of origin prior to slaughter were initially analysed using a univariable approach with the chi-square test, and subsequently with a multivariable logistic regression model to assess the combined impact of these animal characteristics with the risk of having a bovine TB-like lesion. Additionally, and as a secondary objective, tissue samples were collected from all carcases that had a bovine TB-like lesion and were processed using standard Mycobacterium culture and identification methods. The culture and acid fast positive samples were tested using Capilia TB-neo® assay to identify Mycobacterium tuberculosis complex (MTC).


RESULTS
Of 1,576 carcasses inspected, 9.7% (153/1,576) had bovine TB-like lesions from which Mycobacterium spp and Mycobacterium Tuberculosis Complex (MTC) were isolated in 13 (8.4%) and 12 (7.8%) respectively. Bovine TB-like lesions were more likely to be found in females (OR = 1.49, OR 95% CI: 1.06-2.13) and in older cattle (OR = 2.5, 95% CI: 1.64-3.7). When compared to Ankole cattle, Cross breed (OR = 6.5, OR 95% CI: 3.37-12.7) and Zebu cattle (OR = 2.57, 95% CI: 1.78-3.72) had higher odds of having bovine TB-like lesions. Animals from Kasanda (OR = 2.5, 95% CI: 1.52-4.17) were more likely to have bovine TB-like lesions than cattle from Kasambya.


CONCLUSIONS
The findings of study reveals that approximately one in ten slaughtered cattle presents with gross pathology suggestive of bovine TB in Mubende district in the Uganda cattle corridor district, however, we isolated MTC in only 8.4% of these bovine TB-like lesions. Therefore, there is a need to understand the cause of all the other bovine TB-like lesions in order to safe guard diagnostic integrity of meat inspection in Uganda.
Department of Biosecurity Ecosystem and Veterinary Public Health, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda.
Daniel Pakasi
DP
Nalapa
Division of Genetics and Genomics, The Roslin institute, University of Edinburgh, Easter bush Campus, EH259RG, Edinburgh, UK.
Adrian
A
Muwonge
Department of Biosecurity Ecosystem and Veterinary Public Health, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda. clokankya@yahoo.com.
Clovice
C
Kankya
College of Veterinary Medicine and Biomedical Sciences, Department of Clinical Sciences & Mycobacteria Research Laboratories, Colorado State University, Fort Collins, CO, USA.
Francisco
F
Olea-Popelka
D000818:Animals; D002417:Cattle; D005260:Female; D005513:Food Inspection / Q000379:methods; D008198:Lymph Nodes / Q000382:microbiology / Q000473:pathology; D008297:Male; D009163:Mycobacterium bovis / Q000302:isolation & purification*; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification*; D015995:Prevalence; D014380:Tuberculosis, Bovine / Q000175:diagnosis / Q000453:epidemiology*; D014454:Uganda / Q000453:epidemiology
Bovine tuberculosis; Tuberculous -like lesions; Uganda cattle corridor