The pig, often called swine, hog, or domestic pig when distinguishing from other members of the genus 'Sus', is an omnivorous, domesticated even-toed ungulate.

The pig's head-plus-body length ranges from 0.9 to 1.8 m (3 to 6 ft), and adult pigs typically weigh between 50 and 350 kg (110 and 770 lb), with well-fed individuals even exceeding this range. The size and weight of hogs largely depends on their breed. Pigs grunt and make snorting sounds.

When used as livestock, pigs are farmed primarily for the production of meat, called pork. A group of pigs is called a passel, a team, or a sounder. The animal's bones, hide, and bristles are also used in products. Pigs, especially miniature breeds, are kept as pets.

Because of their relative lack of sweat glands, pigs often control their body temperature using behavioural thermoregulation. Wallowing, which often consists of coating the body with mud, is a behaviour frequently exhibited by pigs.

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