Mycobacteria in the environment of pig farms in the Czech Republic between 2003 and 2007

Abstract

ABSTRACT:In the Czech Republic, most mycobacterial infections in pigs are caused by the Mycobacterium avium complex (MAC) and potentially pathogenic mycobacteria (PPM) derived from the environment. This study was undertaken after the isolation of PPM from various components of the environment of pig herds between 1996 (Matlova et al., Veterinarni Medicina, 48, 2003. Between 2003 and 2007, a total of 1114 environmentally-derived samples from 24 farms were examined. After staining according to Ziehl-Neelsen, acidfast rods were found in 42 (3.8%) samples by direct microscopy, and PPM were isolated from 223 (20.0%) samples by culture. PPM occurred primarily in soil from the paddocks (53.8%), peat (53.2%), bedding (28.4%) and biofilm from the pipeline (21.0%). From MAC, M. avium subsp. hominissuis (MAH) genotype IS901-and IS1245+ was most frequent; M. avium subsp. avium (MAA) genotype IS901+ and IS1245+ and M. intracellulare genotype IS901-and IS1245-were isolated from one (0.4%) and three (1.3%) samples, respectively. The remaining isolates were identified as 19 other mycobacterial species: M. gordonae (n = 8), M. triviale (n = 6), M. flavescens (n = 3), M. nonchromogenicum (n = 3), M. terrae (n = 3), M. xenopi (n = 3), M. fortuitum (n = 2), M. chelonae (n = 2), M. chitae (n = 2), M. abscessus (n = 1), M. gastri (n = 1), M. kumamotonense (n = 1), M. marinum (n = 1), M. parafortuitum (n = 1), M. peregrinum (n = 1), M. porcinum (n = 1), M. scrofulaceum (n = 1), M. smegmatis (n = 1) and M. simiae (n = 1). The remaining 41 isolates of unidentified mycobacterial species did not contain the sequences IS901 and/or IS1245, specific for medically important members of MAC (MAA and MAH); a further 44 isolates were not tested due to their contamination or loss of ability to grow in vitro. A farm where MAH was often detected in the lymph nodes of pigs and in the environment between 1996 and 2002 (Period I), was selected for further investigation between 2007 (Period II). A comparison of the findings of mycobacteria on the investigated farm in Period I and in the following Period II showed a significant increase (P < 0.01) in the occurrence of mycobacteria other than MAH, especially in peat samples.

Mycobacteria in peat used as a supplement for pigs: failure of different decontamination methods to eliminate the risk

“…The rate of mycobacterial contamination ranged from 63 to 100% with the predominant isolate being M. a. hominissuis (82.1%), followed by M. fortuitum and M. gordonae (3.5%). This finding concurs with previous studies in which M. a. hominissuis was detected most frequently Krizova et al 2010). M. a. hominissuis as well as other PPM and environmentally saprophytic mycobacteria (which were also found in peat), can induce the development of tuberculous lesions in mesenteric lymph nodes in pigs Matlova et al 2005;Shitaye et al 2006).…”

“…Investigations into the external sources of infection causing the tuberculous lesions revealed that the primary source of MAC was peat fed as a supplement Trckova et al 2006a,b). Various species of PPM have been detected in peat with M. a. hominissuis the most often isolated Krizova et al 2010). In Germany, peat was also found to be a major source of mycobacteria in pigs as early as the mid-1970s (Engel et al 1978.…”

Mycobacterium avium subsp. hominissuis infection in two sibling Fjord horses diagnosed using quantitative real time PCR: a case report

“…a. hominissuis is a potential pathogen commonly occurring in the environment, above all in soil and water (Kazda et al, 2009;Kaevska and Hruska, 2010a,b;Krizova et al, 2010). It can infect humans, and is frequently isolated from children with peripheral lymphadenopathy (van Coppenraet et al, 2008).…”

Examination of Mycobacterium avium subsp. avium distribution in naturally infected hens by culture and triplex quantitative real time PCR

“…At present, the environment and infected animals remain the main reservoir for NTM including MAA (Kazda et al, 2009;Krizova et al, 2010)). Although various sources of infection in the environment exist (i.e.…”