The aim of the present study was to evaluate the use of an immunochromatographic test (ICT) strip using recombinant MPB70 (rMPB70) protein as a complementary tool for the diagnosis of naturally occurring tuberculosis in cattle. The study was performed on 249 cattle from populations known to be free from Mycobacterium bovis (M. bovis) and 119 cattle with M. bovis infection, confirmed postmortem. Compared to reference standards (culture isolation and/or visible lesion), the sensitivity of ICT was 94.12% (95% CI: 89.89∼98.35%) while the specificity was 96.80% (95% CI; 94.62∼96.82%). The findings indicate that the ICT strip is efficient for diagnosing bovine tuberculosis in cattle from Korea.

Tuberculosis (TB) is a significant disease for both humans and animals worldwide. The genus Mycobacterium includes several species that cause TB disease in humans and other animals. Amongst the members of the Mycobacterium tuberculosis complex (MTC), M. tuberculosis is mainly a human pathogen, whereas M. bovis has a broad host range and is the principal agent responsible for TB in domestic and wild mammals. M. bovis also infects humans, causing zoonotic TB through ingestion, inhalation. M. bovis accounts for only a small percentage of the reported cases of TB in humans. In recent years, TB in farmed deer has become a disease as public health importance in several countries. Nowadays, there has been rapid outbreak of bovine TB in cattle and deer in Korea. Investigations are needed to elucidate the relative importance of M. bovis on TB incidence in humans, especially in Korea where bovine TB remains a problem. Also, the human sources as the cause of animal infection, M. tuberculosis from the farm workers also important for TB control of animals in Korea. Differentiation between the causative organisms may only be achieved by sophisticated laboratory methods involving bacteriological characteristics, biochemical properties, and routine resistance to pyrazinamide (PZA). M. bovis shows inherently resistant to PZA whereas M. tuberculosis is susceptible to PZA. In this study, we developed a multiplex-PCR assay based on a 12.7-kb fragment for the differential detection of M. bovis and M. tuberculosis. A total of 131 M. tuberculosis complex isolates were randomly obtained from cattle and deers that were PPD positive. they all yielded M. bovis. M. tuberculosis was not isolated from animals. and, a total of 25 M. tuberculosis complex isolates which is resistant to PZA were obtained from patient. PZA resistant MTC in humans was caused entirely by M. tuberculosis. The multiplex-PCR protocol was highly species-specific and time saving for identification of M. bovis and M. tuberculosis. This multiplex-PCR assay will be easily used as a routine monitoring tool in veterinary and medical laboratories.

There are many researches about the contribution of virginiamycin use in animals to quinupristin/dalfopristin (Q/D) resistance in humans. In this study, the prevalence and mechanisms of streptogramin resistance in Enterococcus faecium from chickens were investigated. A total of 170 E. faecium isolates from 38 chicken farms was tested for antimicrobial susceptibility. Eleven (6.5%) E. faecium isolates were found to be resistant to Q/D. The vatE and ermB genes were detected in 2 (18%) and 6 (55%) of Q/D-resistant E. faecium respectively. By using pulsed-field gel electrophoresis (PFGE), 6 distinct PFGE patterns were identified. These data indicate that Q/D resistance among E. faecium from chickens remains low despite the long history of virginiamycin use. However, we have to concern over antimicrobial resistance in bacteria originated from animals, including the possibility of transfer of resistance genes from animal to human.

Nontuberculous mycobacteria (NTM) often confounds the interpretation of skin test in tuberculosis diagnosis, resulting in false-positive reaction. And, NTM are emerging pathogens that cause opportunistic infections in both humans and animals. The prevalence of NTM on human disease has been well investigated, whereas that of NTM on animal disease is not well established in Korea. The aim of this study was to determine the prevalence of NTM on cattle, which did not have symptoms of tuberculosis disease. A total of 426 isolates were collected in Korean native cattle and dairy cattle from 2007 to 2010. The most frequently isolated organisms were Mycobacterium peregrimum (n=5, 28%), Mycobacterium fortuitum (n=3, 17%), Mycobacterium intracellulare (n=2, 11%), Mycobacterium phlei (n=1, 5.6%), Mycobacterium terrae (n=1, 5.6%), Mycobacterium llatzerense (n=1, 5.6%), and Norcadia spp. (n=1, 5.6%). It seems to be necessary to further study the prevalence of NTM on environment (water, soil, feces) as well as animals.