In this study, products from all steps of anaerobic digestion at a farm-scale biogas plant supplied with manure from paratuberculosis-affected dairy cattle were examined and quantified for the presence of the causal agent of paratuberculosis, Mycobacterium avium subsp. paratuberculosis, using culture and quantitative real-time PCR (qPCR). Viable M. avium subsp. paratuberculosis cells were detected using culture in fermentors for up to 2 months; the presence of M. avium subsp. paratuberculosis DNA (10 1 cells/g) was demonstrated in all anaerobic fermentors and digestate 16 months after initiation of work at a biogas plant, using IS900 qPCR. F57 qPCR was able to detect M. avium subsp. paratuberculosis DNA (10 2 cells/g) at up to 12 months. According to these results, a fermentation process that extended beyond 2 months removed all viable M. avium subsp. paratuberculosis cells and therefore rendered its product M. avium subsp. paratuberculosis free. However, M. avium subsp. paratuberculosis DNA was found during all the examined periods (more than 1 year), which could be explained by either residual DNA being released from dead cells or by the presence of viable cells whose amount was under the limit of cultivability. As the latter hypothesis cannot be excluded, the safety of the final products of digestion used for fertilization or animal bedding cannot be defined, and further investigation is necessary to confirm or refute this risk.

The aim of this study was to demonstrate the persistence of Mycobacterium avium subsp. paratuberculosis (MAP) in soil and colonization of different plant parts after deliberate exposure to mouflon feces naturally contaminated with different amounts of MAP. Samples of aerial parts of plants, their roots, and the soil below the roots were collected after 15 weeks and examined using IS900 real-time quantitative PCR (qPCR) and cultivation. Although the presence of viable MAP cells was not demonstrated, almost all samples were found to be positive using qPCR. MAP IS900 was not only found in the upper green parts, but also in the roots and soil samples (from 1.00 × 10(0) to 6.43 × 10(3)). The level of soil and plant contamination was influenced mainly by moisture, clay content, and the depth from which the samples were collected, rather than by the initial concentration of MAP in the feces at the beginning of the experiment.

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Microarrays represent a modern powerful technology, which have potential applications in many areas of biological research and provide new insights into the genomics and transcriptomics of living systems. The aim of this review is to describe the application of microarray technology for Mycobacterium avium subsp. paratuberculosis (MAP) research. The main focus points include a summary of results obtained for MAP using microarrays, examination of the fields of MAP research which are currently being investigated and possible areas of future research. This article is divided into two parts according to the type of nucleic acid used for array hybridisation. Articles related to MAP research using microarray technology are then divided according to the field of study, such as comparative genome analysis, diagnostics, expression or environmental studies.

The objectives of this study were to investigate <i>Mycobacterium avium</i> subsp.<i> paratuberculosis</i> (<i>MAP</i>) distribution in various tissues, in faeces and in milk samples from 131 animals originating from one imported Jersey cattle herd from Denmark. <i>MAP</i> was detected by culture in 37.4% animals. Massive <i>MAP</i> growth was most often observed in the small intestines (48 animals). The lowest levels of <i>MAP</i> were found in spleen and mammary gland samples. <i>MAP</i> was detected in the faeces of 8.4% animals; however, milk samples were <i>MAP</i> negative by culture. The highest prevalence of <i>MAP</i> infection (42.9%) was in age Group B (1.6 to 3 years) and the lowest (6.1%) in group D (more than 8 years). Seven positive calves were detected in the youngest age group; one of them was less than one month of age, which could imply an intrauterine infection. <i>MAP</i> shedding in faeces by a five-month-old calf was also confirmed. The IS<i>900</i> RFLP (restriction fragment length polymorphism) type B-C1 was identified in all animals.