A detailed analysis of sources and routes of Mycobacterium avium subsp. paratuberculosis (MAP) infection in different areas of Germany will be performed. The results of these investigations will allow conclusions and recommendations for more effective control measures.MAP isolates from cattle and sheep from different regions and herds in Germany were analysed. Furthermore, isolates from different tissues and organs of the same animals were studied in order to establish whether different MAP strains can be found in one animal. The strains were typed by restriction fragment length polymorphism analysis (RFLP) of the insertion segment IS900 (Pavlik et al. J Microbiol Meth 1999; 38:155-167) using three different restriction enzymes, and by the amplification of specific "mycobacterial interspaced repetitive units" (MIRU-PCR; Bull et al. Mol Cell Probe 2003; 17:157-164).The diversity of RFLP patterns was different in the herds. A relatively high heterogeneity with eight different RFLP types for 15 MAP strains was found within isolates from cattle of one herd, which had a high entrance of cattle with unknown infection state in the past. A number of new RFLP-types were detected. According to our current results, individual animals were not infected consecutively by different MAP strains. Among the isolates from sheep, two new, unique so called I-types were detected. Furthermore, strains with "cattle-type" RFLP patterns were also found in sheep. Two different MIRU types were found in sheep isolates only, and a third type that was also common in cattle isolates.Trade of sub-clinically infected cattle with unknown infection state is considered the main route for the spread of MAP between herds. Contamination of pasture with MAP by cattle dung is claimed to be a cause of infection of migrating sheep and for the spread of MAP strains originating from cattle in this way.

Sponsorship

Attendance to this Congress was sponsored by the EU-funded project SSPE-CT-2004-501903.