Tuberculous lesions in pigs in the Czech Republic in the years 1990-1999

In the Czech Republic, bovine tuberculosis in cattle was controlled in 1968. The last outbreak was diagnosed in cattle and domestic pigs in 1995. During the veterinary hygiene inspection of pigs slaughtered in slaughterhouses, however, tuberculous lesions were still being found above all in the head and intestinal lymph nodes. In the decade monitored a total of 45 873 318 pigs were slaughtered and examined according to veterinary hygiene standards. Apart from 1991, when results of tuberculous findings were not obtained, tuberculous lesions were found in 134 088 (0.32%) of the 41 458 565 pigs examined in the remaining nine years. During a detailed analysis of the pathological anatomical examination of 190 940 pigs slaughtered in one district, tuberculous lesions in lymph nodes were found in 4 107 (2.2%) pigs: mesenteric (65.3% pigs), submandibular (18.6% pigs), inguinal (0.1% pigs) and simultaneously intestinal and head lymph nodes (15.9% pigs). Miliary tuberculosis was found only in the parenchymatous organs of four (0.1%) pigs. The following financial losses resulted: 6% for confiscating the head, intestines and stomach, and 22 to 24% for assessing meat as conditionally edible after processing, i.e. intended only for heat-processed products. Mycobacteria were isolated from 7 246 (41.8%) pigs through the cultivation of tissue samples from 17 326 pigs. Mycobacterium bovis was detected in only five (0.07%) animals which originated from the last outbreak of bovine tuberculosis in cattle in the Czech Republic in 1995. M. avium complex (MAC) isolates came from 6 870 (94.8%) animals: 55.7% M. a. avium isolates were mainly of serotypes 2 and 3 and genotype IS901+ and IS1245+ and 39.2% M. a. hominissuis isolates were mainly of serotypes 4, 8 and 9 and genotype IS901- and IS1245+. Conditionally pathogenic mycobacteria (M. chelonae, M. terrae, M. phlei and M. fortuitum) were isolated from 371 (5.1%) pigs. In the whole period monitored, two marked increases In the findings of tuberculous lesions were recorded: In the mid-1990s as a result of using deep bedding with wood shavings and at the end of the 1990s as a result of supplementing the pigs’ feed with peat

Mycobacterial contamination of environment in pig farms in the Czech Republic between 1996 and 2002

The purpose of this study was to find source of mycobacterial infections in pig farms. A total of 2 411 environmental samples (bedding materials, water, biofilm from pipelines, peat, etc.) were examined by microscopy and culture. Isolates were identified by serotyping and PCR. Mycobacteria were isolated from 579 (24.0%) samples. 47.0% isolates were Mycobacterium avium subsp. hominissuis isolates (IS901-, IS1245+, serotypes 4, 6, 8, 9), 2.2% isolates were M. a. avium (IS901+, IS1245+, serotype 2) and 50.8% belong to atypical mycobacteria comprising of fifteen species. The frequent isolates were found in peat samples (213/65.1%) in which 81.2% isolates comprised M. a. hominissuis. High amount of mycobacteria were isolated from biofilm (36.4%) and water (29.6%). Alike peat, non-pathogenic species were predominant. The third sources of mycobacteria were bedding materials, mostly sawdust (43.6%). Presence of mycobacteria in the animals’ environment leads to economic losses due to meat condemnation in abattoirs

Integrated MicroRNA-mRNA-Analysis of Human Monocyte Derived Macrophages upon Mycobacterium avium subsp. hominissuis Infection

Many efforts have been made to understand basal mechanisms of mycobacterial infections. Macrophages are the first line of host immune defence to encounter and eradicate mycobacteria. Pathogenic species have evolved different mechanisms to evade host response, e.g. by influencing macrophage apoptotic pathways. However, the underlying molecular regulation is not fully understood. A new layer of eukaryotic regulation of gene expression is constituted by microRNAs. Therefore, we present a comprehensive study for identification of these key regulators and their targets in the context of host macrophage response to mycobacterial infections.We performed microRNA as well as mRNA expression analysis of human monocyte derived macrophages infected with several Mycobacterium avium hominissuis strains by means of microarrays as well as quantitative reverse transcription PCR (qRT-PCR). The data revealed the ability of all strains to inhibit apoptosis by transcriptional regulation of BCL2 family members. Accordingly, at 48 h after infection macrophages infected with all M. avium strains showed significantly decreased caspase 3 and 7 activities compared to the controls. Expression of let-7e, miR-29a and miR-886-5p were increased in response to mycobacterial infection at 48 h. The integrated analysis of microRNA and mRNA expression as well as target prediction pointed out regulative networks identifying caspase 3 and 7 as potential targets of let-7e and miR-29a, respectively. Consecutive reporter assays verified the regulation of caspase 3 and 7 by these microRNAs.We show for the first time that mycobacterial infection of human macrophages causes a specific microRNA response. We furthermore outlined a regulatory network of potential interactions between microRNAs and mRNAs. This study provides a theoretical concept for unveiling how distinct mycobacteria could manipulate host cell response. In addition, functional relevance was confirmed by uncovering the control of major caspases 3 and 7 by let-7e and miR-29a, respectively

Mycobacterial contamination of environment in pig farms in the Czech Republic between 1996 and 2002

The purpose of this study was to find source of mycobacterial infections in pig farms. A total of 2 411 environmental samples (bedding materials, water, biofilm from pipelines, peat, etc.) were examined by microscopy and culture. Isolates were identified by serotyping and PCR. Mycobacteria were isolated from 579 (24.0%) samples. 47.0% isolates were Mycobacterium avium subsp. hominissuis isolates (IS901-, IS1245+, serotypes 4, 6, 8, 9), 2.2% isolates were M. a. avium (IS901+, IS1245+, serotype 2) and 50.8% belong to atypical mycobacteria comprising of fifteen species. The frequent isolates were found in peat samples (213/65.1%) in which 81.2% isolates comprised M. a. hominissuis. High amount of mycobacteria were isolated from biofilm (36.4%) and water (29.6%). Alike peat, non-pathogenic species were predominant. The third sources of mycobacteria were bedding materials, mostly sawdust (43.6%). Presence of mycobacteria in the animals’ environment leads to economic losses due to meat condemnation in abattoirs.</p

Tuberculous lesions in pigs in the Czech Republic in the years 1990-1999

In the Czech Republic, bovine tuberculosis in cattle was controlled in 1968. The last outbreak was diagnosed in cattle and domestic pigs in 1995. During the veterinary hygiene inspection of pigs slaughtered in slaughterhouses, however, tuberculous lesions were still being found above all in the head and intestinal lymph nodes. In the decade monitored a total of 45 873 318 pigs were slaughtered and examined according to veterinary hygiene standards. Apart from 1991, when results of tuberculous findings were not obtained, tuberculous lesions were found in 134 088 (0.32%) of the 41 458 565 pigs examined in the remaining nine years. During a detailed analysis of the pathological anatomical examination of 190 940 pigs slaughtered in one district, tuberculous lesions in lymph nodes were found in 4 107 (2.2%) pigs: mesenteric (65.3% pigs), submandibular (18.6% pigs), inguinal (0.1% pigs) and simultaneously intestinal and head lymph nodes (15.9% pigs). Miliary tuberculosis was found only in the parenchymatous organs of four (0.1%) pigs. The following financial losses resulted: 6% for confiscating the head, intestines and stomach, and 22 to 24% for assessing meat as conditionally edible after processing, i.e. intended only for heat-processed products. Mycobacteria were isolated from 7 246 (41.8%) pigs through the cultivation of tissue samples from 17 326 pigs. Mycobacterium bovis was detected in only five (0.07%) animals which originated from the last outbreak of bovine tuberculosis in cattle in the Czech Republic in 1995. M. avium complex (MAC) isolates came from 6 870 (94.8%) animals: 55.7% M. a. avium isolates were mainly of serotypes 2 and 3 and genotype IS901+ and IS1245+ and 39.2% M. a. hominissuis isolates were mainly of serotypes 4, 8 and 9 and genotype IS901- and IS1245+. Conditionally pathogenic mycobacteria (M. chelonae, M. terrae, M. phlei and M. fortuitum) were isolated from 371 (5.1%) pigs. In the whole period monitored, two marked increases In the findings of tuberculous lesions were recorded: In the mid-1990s as a result of using deep bedding with wood shavings and at the end of the 1990s as a result of supplementing the pigs’ feed with peat.</p