Undisturbed observation
Undisturbed observation means that animals are observed from a distance with the least possible disruption. Ideally, a camera is set up in the animal room and the images are viewed in another location. This is not always feasible. In that case, the observer should enter the animal room as quietly as possible and wait a while, before starting the observation.
Aspects to be evaluated:
- Activity: Healthy mice and rats are active but they also have rest periods which become more frequent as the animal gets older. Mice and rats are nocturnal animals and their active phase is during hours of darkness. Aberrant behavior will occur earlier and be more pronounced during the active phase. It is recommended to observe the animals in the dark if the active phase is relevant for the experiment. This can be done using infra red light.
- Social interactions: Are these normal (e.g. playing, determining dominance, sleeping) or abnormal (e.g. fighting, isolation from the group, barbering)? Vocalization (making sounds) is another aspect of rodent interaction.
- Alertness: An alert animal explores and evaluates its environment by behaviors such as rearing up and sniffing.
- Grooming: A healthy animal pays frequent attention to the care of its body.
- Abnormal behavior such as restlessness, circling , bizarre fighting, stereotypic behavior , lethargy, vocalization , etc.
- Abnormal physical appearance: The occurrence of malformations or abnormal development (e.g. hydrocephalus , tumor, growth retardation.
Undisturbed observation should also include observation of the environment, e.g. the cage and bedding, for abnormal findings (e.g. feces, blood, etc.)
