ABSTRACT
The minipig used in biomedical research is susceptible to all diseases that affect the commercial swine population. The laboratory minipig is often microbiologically de¢ned and has generally not been exposed to as many pathogenic agents as pigs from commercial pig herds. The micro biological background of the minipig is often known to a large extent and thus the minipigs can be considered comparable with respect to microbiology when they are obtained from the supplier of the strain used. When using microbiologically-de¢ned minipigs, it is necessary to consider the microbiological status of the test facility in which the minipigs are housed. If production pigs are housed in the same test facility, pigs obtained from a commercial pig breeder most likely harbour pathogenic agents subclinically, in which case disease is probably not clinically apparent. Subclinical infections can be dormant, in which the agent can be recovered, or latent, in which the agent can only be identi¢ed to be present by using indirect methods. Some agents infect the animal only temporarily while others cause a lifelong infection. A disease outbreak may be experienced if microbiologically de¢ned minipigs are exposed to pathogens that they have not been in contact with a priori. It is important to be able to recognise the presence of disease, to know how microorganisms behave, and to be able to evaluate their possible inœuence on conducting studies. To evaluate which microorganisms could pose a threat to runnig studies in a research laboratory, it is important to know the health status at the minipig breeder and to be aware of diseases present in the region of the test facility, and it is advisable to implement a health monitoring programme at the test facility. The zoonotic potential of some pathogens also need to be addressed. National and international legislations concerning handling of diseases in the area must be known. Besides national legislations, infections in pigs and other species are governed by the World Organisation for Animal Health (Of¢ce Internal des Epi zooties, OIE), which is an intergovernmental organisation aimed at improving animal health worldwide. Members of the OIE are responsible for reporting diseases listed by the OIE, if encountered (https:// www.oie.int/eng/OIE/en_about.htm?e1d1).
