Abstract
Bovine tuberculosis (BTB) is a considerable threat to livestock keepers and public health in many developing and underdeveloped countries. We investigated associations between 20 microsatellite markers and three phenotypes for BTB in a sample of the Chadian cattle population. The phenotypes measured were: 1) single intra-dermal comparative cervical tuberculin test (SICCT) performed on live animals, 2) presence of lesion post-slaughter, 3) a bacteriological tissue culture test for Mycobacterium bovis using the samples with observed lesions and 4) a predicted Bayesian model (BM) estimate of a true BTB disease status using all tested animals. All traits were recorded in binary form and as either 1 = presence or 0 = absence. A total of 224 animals for SICCT, lesion and BM traits and 96 animals with bacteriological culture test were genotyped. Generalised linear models were fitted to the binary BTB phenotypes that consisted of age (covariate), sex (2 levels), breed (2 levels) and markers (alleles: 5 - 14 levels) as explanatory variables and implemented in R using glm with a logit link function. The model was fitted for each marker, separately. Six out of 20 markers tested were significantly associated with at least one trait considered; these were ILSTS005, ILSTS006, TGLA227, BM2113 and CSRM66. Genomic regions around these markers may serve as a basis for further functional investigations. This is the first study to report association of microsatellite markers with bovine tuberculosis traits in African or Chadian cattle population.
Highlights
Mycobacterium bovis causes bovine tuberculosis (BTB), an important disease of domesticated cattle that has a major economic and health impact throughout the world [1]
Out of 224 animals used in the analyses, there were 29%, 48% and 28% animals positive for tuberculin skin test, post-slaughter lesion detected and Bayesian estimate for true BTB disease status, respectively, whereas for the 96 tissue culture samples, 52% animals were confirmed for the presence of acid fast bacilli, an indicator of Mycobacterium sp
The aim of this paper was to investigate a possible association between a panel of microsatellite markers and BTB phenotypes
Summary
Mycobacterium bovis causes bovine tuberculosis (BTB), an important disease of domesticated cattle that has a major economic and health impact throughout the world [1]. Agricultural losses due to BTB are estimated at around $3 billion annually [2]. Tuberculosis in humans causes almost two million deaths annually [3] and tuberculosis incidence is rapidly increasing in sub-Saharan African countries, fuelled by the concurrent HIV epidemic [4]. The incidence of BTB has been significantly reduced or eradicated from domestic cattle in many developed countries by state compensation of a test and cull policy that removes infected cattle [5]. A study on two main Chadian zebu cattle (Arab and Mbororo) populations estimated the incidence of BTB to be 11% [7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
