Microbiological health monitoring in KEKS

Microbiological health monitoring is performed in accordance with the FELASA guidelines.

Mouse barrier

  • Samples are collected three times a year.
  • As a rule, samples are collected from sentinel animals. For a minimum of two months before sampling, dirty bedding from other cages of the animal room will be moved to the sentinel cage at every cage change. Food and water bottle are also always transferred from other cages to the sentinel cage. This way the possible unwanted pathogenic microbes in the animal room are more likely to be transmitted to the individual being examined. Alternatively, it is also possible to select random animals from each animal room for the health monitoring.
  • Blood samples are serologically examined for microbe antibodies
  • Swab samples are collected from the pharynx, vagina or foreskin, and caecum for bacterial culture.
  • PCR assays may be done from e.g. faeces, contents of the caecum, intestinal lymph nodes or external swab samples.
  • The skin and fur are microscopically examined for external parasites. Faeces and the contents of the small intestine and caecum are examined for intestinal parasites.
  • Animals are superficially inspected when collecting the samples. If necessary, a more detailed pathological examination is conducted.
  • The samples are examined in external laboratories. The skin and fur and the intestinal contents are microscopically examined at KEKS.
  • The microbe checklist, findings, methods of analysis and research laboratories are described in the health monitoring report.


Research unit

Mice and rats

Health monitoring rounds based on the FELASA recommendations are performed at the research unit less frequently than in the mouse barrier, but at minimum once a year.


Rabbits are not bred in KEKS. They are instead ordered separately for each experiment from a commercial laboratory animal producer. Since the delivered animals are high-level in terms of their health and microbiological level, KEKS does not perform routine health monitoringsamplings. If the rabbits exhibit clinical signs that may be due to an infection, the examinations to be made will be decided on a case-by-case basis.


Swine used in experiments are purchased from a production pig farm which has a prevention and health monitoring programme in case of clinical illnesses or microbes that could cause production losses. When the pigs are brought in KEKS, they are inspected in case of health problems. Samples are collected and examined if necessary, in case there is reason to suspect a contagious disease.


Sheep are purchased from a farm that is involved in the national contagious sheep disease monitoring programme. In addition, the farm must have a veterinary care agreement with the municipal veterinarian. The agreement includes monitoring production conditions and preventive health care. When the sheep are brought in KEKS, they are inspected in case of health problems. Samples are collected and examined  if necessary, in case there is reason to suspect a contagious disease.


Microbiological monitoring findings in KEKS

The mouse barrier was emptied, disinfected and repopulated in December 2014. No primary pathogens listed in the FELASA guidelines have been found ever since. However, in the monitoring 5.5.2015, Staphylococcus aureus and Pseudomonas aeruginosa were detected in immunocompromised (athymic) nude mouse sentinels. S. aureus has also later been isolated from preputial gland abscesses that occasionally develop in otherwise healthy C57 breeding males, although the health monitoring results of the sentinel mice have been negative ever since the 5.5.2015 monitoring round.

In the research unit, mouse norovirus (MNV) has been detected in mice and Streptococcus agalactiae in rats. As mice are brought from the mouse barrier into the research unit for use in experiments, it is apparent that S. aureus is prevalent in the research unit as well.

All the abovementioned microbes are harmless in healthy, immunocompetent animals, and probably do not affect most of the research conducted in KEKS. However, researchers should be aware of the possibility of these infections, and should consider their possible effects when planning experiments. If needed, e.g. when conducting experiments with immunocompromised animals, special housing arrangements can be made to protect the animals from infections.


Information on the microbes

Murine / mouse norovirus, MNV
MNV, Charles River technical sheet

Staphylococcus aureus, Charles River technical sheet

Streptococcus agalactiae  (β–hemolytic streptococcus, group B), Charles River technical sheet

Pseudomonas aeruginosa, Charles River technical sheet

Last updated: 30.12.2016