Pain associated behaviour

Acute pain and stress are often associated with jumping, freezing, squeaking, biting, escape behaviour, and sunken sides (in case of abdominal pain).

Rats seldom vomit. They are able to passively cast up or regurgitate food. When a rat is 'nauseated', it may repeatedly lift its head in a motion resembling gagging. They can also display pica-behaviour, which is defined as eating bedding material or other strange, non-food objects.

When rats experience pain, they communicate by squeaking, whistling and screeching, and by producing ultrasound.