To comprehend what an animal test means for a mouse or a rat it is helpful to learn something about the life of these rodents.

Mice and rats are feeling and communicating living beings. Mice have a good possibility of communicating with each other in their mouse language. For the medical ear, these are only several vocal utterances perceivable as cries of fear, pain and threat. Our ears cannot hear the actual mouse language, because their main vocabulary lies in the ultrasonic range. Aside from their language, mice possess, also perceivable to people, a well-defined body language. From people, we know that their body language, that is, their posture and movements, are controlled by their thoughts and feelings. It is similar with mice, rats and guinea pigs. You can deduce from their movements what is going on in them: fear, caution, attention and curiosity, relaxation and a feeling of security can be recognized very well in mice by, for example, their posture, how they hold their head and the position of their ears.

Human beings and animals perceive their surroundings via their senses. The more sensitive their senses of smell, sight, hearing, taste and touch are, the more intensively they experience their surroundings. The senses of animals react in part more finely than those of people. The keenest sense in mice is their sense of smell. A mouse’s ability to smell is comparable to a dog’s nose, and dogs are considered to be the mammals with the »best« noses. Mice smell their food, the individual members of their family, their territory, their partner and strangers. A mouse’s life is strongly marked by this. Another well-developed and important sensory organ of mice is their whiskers. They react very sensitively to every touch and help the mouse to find its way around well at night or in darkness. With help of its whiskers, a mouse can very quickly calculate whether a hole, or passage or crack is big enough for it to fit through. With their highly developed senses, mice experience their surroundings very intensively, perhaps even more intensively than man experiences his. How then must they feel their imprisonment in a laboratory cage and the experiments that are carried out on them?

A mouse’s sense of hearing is also very well developed. In comparison to people, mice can perceive much higher tones. This is also connected to their spoken language, which lies primarily in the ultrasonic range.

As opposed to its senses of hearing, smell and touch, a mouse’s vision is quite poorly developed. A mouse sees well only very close up. But, due to the lateral position of its eyes on its head, it has a nearly perfect all-around vision and can very quickly perceive movements – approaching enemies or hands reaching into its cage.