A healthy mouse

The laboratory mouse’s closest genetic relative is the wild mouse: Mus musculus. Knowledge of the behaviour of the wild species provides information, which is helpful in assessing the well-beingWell-being A complex and dynamic internal state that includes: successful biologic functioning, positive experiences, and absence of negative conditions. The animal adapts effectively to internal needs and external stimuli and maintains a good mental state. of a laboratory mouse.

The way in which a laboratory mouse can engage in its natural behavioural repertoire (e.g. nesting behaviourNesting behaviour The behaviour of animals, in particular rodents such as rats and mice, aimed at creating a nest if suitable cage materials are present. The presence of such nest building materials can be considered an enrichment., see the movie “Nesting behaviour and huddlingHuddling Crowding together of a group of animals (usually while resting).”), determines in no small measure its state of well-being. Multiple strains of laboratory mice are available, both inbred and outbred stock. Genetic modification technology has greatly expanded the number of available lines. Consequently, there is a great diversity in behavioral characteristics and a broad range of physiological normal values.

Mice have a short lifespan with an associated high metabolic rate and rapid maturation and reproduction. In general, they have large litters. A healthy laboratory mouse is alert, curious, engages in social interactions, looks well-nourished and clean, and is vivacious.

Activity

The behavioral pattern of a laboratory mouse is determined in large measure by the opportunities afforded by the environment. Housing of laboratory mice should ideally be predicated on creating conditions that offer the broadest possible range of natural activities such as exploration, resting, climbing, groomingGrooming The behavior animals engage in to keep clean. Grooming removes dirt from fur and body openings. Absence of this behavior indicates reduced well-being., foragingForaging Looking for and collecting food., nesting, and social behaviourSocial behaviour The gamut of behaviours displayed by an animal in the presence of other animals that are either not displayed when solitary, or are not displayed in the same manner.. To this end, the Council of Europe has set forth a number of guidelines. They are a compromise between the needs of the animal and what is feasible in a laboratory setting.