In this study, the presence of Mycobacterium avium subspecies paratuberculosis (MAP) in the animal collection of the Royal Zoological Society of Antwerp was investigated. The specific situation of zoo facilities (limited space for different animals) is a cause of concern. Up to one third of zoos accredited by the American Zoo and Aquarium assocation have reported the occurrence of at least one infection since 1995. Faecal and post mortem samples of a total of 38 ruminants were tested using bacteriological and molecular methods. Samples were cultured on Löwenstein-Jensen (+ mycobactine J) solid medium and in BACTEC 12B radiometric medium after decontamination with the double incubation method described by Whitlock and Rosenberger. DNA templates of all samples were also subjected to PCR using primers for IS 900. A modified Boom-extraction was used for the post mortem samples whereas faecal samples were extracted using a newly developed protocol based on sequence-capture. No evidence of paratuberculosis was found in the animal collection using both detection tests. One sample in culture became positive for Mycobacterium avium. Accurate diagnosis of MAP is very difficult by current tests. Negative isolation of MAP from animals may be due to the limited distributions of focal lesions, sporadic excretion of the organism or the detection limit of the faecal culture methods. Faeces are a lot easier to sample in a zoo than blood or biopsy material. For these practical reasons, a faecal DNA extraction was developed and used in this study. Faeces contain a lot of PCR-inhibitors and difficulties are experienced in recovering DNA from such complex matrix. Negative PCR results may be due to inhibition or the low detection limit of the PCR.

Conclusion.

We couldn't detect a positive animal in the RZSA with the specific diagnostic tests used.