Guarding - The animal alters its posture to avoid moving or causing contact to a body part, or to avoid the handling of that body area.
Abnormal Appearance - Different species show different changes in their external appearance, but obvious lack of grooming, change posture, and a changed profile of the body can all be observed. In species capable of some degree of facial expression, the normal expression may be altered.
Altered Behavior - Behavior may be depressed; animals may remain immobile, or reluctant to stand or move even when disturbed. They may also exhibit restlessness (e.g., lying down and getting up, shifting weight, circling, or pacing) or disturbed sleeping patterns. Animals in pain may also show altered social interactions with others in their group.
Vocalization - An animal may vocalize when approached or handled or when a specific body area is touched or palpated. It may also vocalize when moving to avoid being handled.
Mutilation - Animals may lick, bite, scratch, shake, or rub a painful area.
Sweating - In species that sweat, excessive sweating is often associated with some types of pain.
Lack of Appetite - Animals in pain frequently stop eating and drinking, or markedly reduce their intake, resulting in rapid weight loss.