SUSCEPTIBILITY OF MICE INTENDED FOR ESCHERICHIA COLI, PSEUDOMONAS AERUGINOSA, SALMONELLA ENTERITIDIS AND STAPHYLOCOCCUS AUREUS INFECTION

Laboratory mice may harbor a variety of viral, bacterial, parasitic, and fungal agents. Frequently, these organisms cause no overt signs of disease. However, many of the natural pathogens of animal may alter host physiology, rendering the host unsuitable for many experimental uses. While the number and prevalence of these pathogens have declined considerably, many still turn up in laboratory animals and represent unwanted variables in research. Investigators using mice in biomedical experimentation should be aware of the profound effects that many of these agents can have on research. What does the future hold regarding the natural pathogens of laboratory mice? Several events can be anticipated. First, the decline in the prevalence of natural pathogens will continue as housing and husbandry methods improve even more. Second, additional effects of currently known pathogens will be reported as new research uses are found for traditional laboratory animals, new questions are asked, and new technologies are applied to those questions. Third, new pathogens will continue to be discovered and reported. Most of these previously unknown agents will not result in clinical disease, but many may affect experimental results. According to Weisbroth (1996), many of these “emerging” pathogens may even be acquired from humans. While the range and magnitude of infections has decreased in laboratory mice, rats, and rabbits, continued diligence and additional study are required to ensure the wellbeing of animals used in biomedical research.