Domestic Pig

## Description

Domestic pigs (Sus domesticus) are commonly known as approachable, loyal, and highly intelligent creatures. These animals are rather large representatives of even-toed ungulates. Additionally, they are noticeably larger and slower than the wild pigs, from which they are bred. This practice helps improve the size, temperament, and other important features of the animals. Crossbreeding with wild pigs such as woolly boars has produced different types of pigs, the most common of which is the domestic pig. The animal is amazingly clean and doesn't tend to soil their home ranges. Those found outside the factory farms typically spend their active time playing or taking sunbaths. These animals are also known to possess a highly-developed sense of smell, which helps them explore their surroundings.

## Appearance

The pig typically has a large head, with a long snout that is strengthened by a special prenasal bone and a disk of cartilage at the tip. The snout is used to dig into the soil to find food and is a very acute sense organ. Pigs have four hoofed toes are on each foot, with the two larger central toes bearing most of the weight, but the outer two also being used on soft ground. Most pigs have rather a bristled sparse hair covering on their skin, although woolly-coated breeds also exist. Pigs are one of four known mammalian species which possess mutations in the nicotinic acetylcholine receptor that protect against snake venom. Mongooses, honey badgers, hedgehogs, and pigs all have modifications to the receptor pocket which prevents the snake venom α-neurotoxin from binding.

## Distribution

Domestic pigs are found all over the world except Antarctica. The ideal habitat for domestic pigs is an area with temperate climatic conditions, where they often live in pig barns with large outdoor yards, where they can spend their time. When a female yields offspring, she usually rears her young inside a special stall, containing enough amounts of straw or wood shavings in order to keep the newborn piglets warm.

## Behavior

Some behavioral patterns of Domestic pigs resemble these of cattle and sheep. However, the behavior of these mammals has considerably more in common with dogs and humans. Thus, they are known to socialize with conspecifics, gathering in small groups, members of which display physical contact such as huddling together. Mud is commonly used as a defense against ultraviolet light. Additionally, wallowing in the mud helps these pigs cool off and remove parasites from their skin. During favorable conditions, they spend all their time feeding and sleeping. Despite the contemporary production systems, these animals naturally tend to construct sleeping sites. Females of this species (known as sows) make nests, where they produce offspring. The creation of wallows and depressions in the ground is another typical behavior of domestic pigs. Communication between individuals occurs through a series of grunting and squeaking sounds.

## Diet

These animals maintain an omnivorous diet, which means that they consume food of both animal and plant origin. However, the greater part of their usual diet is composed of corn, wheat, soy, or barley. Those living on small farms typically feed upon slop, made up of leftover food such as vegetable peels and fruit rinds. When roaming far from their feeding sites, they may find other types of food.

## Reproduction

The Domestic pig is monogamous and mates for life. Domestic pigs exhibit 2 reproductive seasons per year, occurring in summer and winter. Females undergo 114 days of gestation, in other words: 3 months, 3 weeks, and 3 days. Litter size varies between 6 and 8 piglets, although there have been recorded larger litters of up to 12 piglets, which usually happen in case of ideal conditions and enough amount of suitable food. Newborn piglets grow very quickly. They usually weigh 1.5 kg at birth, reaching almost 3 kg at one week old. The babies are weaned at 3 months old, although they typically remain with their mothers for a while. When rearing their offspring, two or more females and their young often live in groups called extended families.

## Population

### Population number

According to Statista, in 2016, there were approximately 784.83 million pigs worldwide.

## Domestication

Domestication history is insufficiently explored by archaeologists, largely due to the nature of the wild boar, from which the domestic pig origins. Wild hogs are represented by several species around the globe, including the Warthog, the Pygmy hog, and the Pig-deer. However, the wild boar is currently the only domesticated species of wild hog. The domestication process of these animals is thought to have occurred around 9,000-10,000 years ago simultaneously in 2 different regions: eastern Anatolia and central China. In course of time, early farmers helped distribute these animals from Anatolia to Europe as well as from central China to the inland regions. They are now bred mainly for their meat known as "pork", whereas their bones, hide and bristles are valuable materials for various commercial products. Additionally, some domestic pigs (particularly, Pot-bellied pigs) are known to be kept as domestic pets.

## Fun Facts

If you try to pick a pig up, the animal will resist until it's back on the ground. Pigs in general are very afraid of being taken up.

In rural areas, you can often hear the saying “living the life of a pig”, which is usually addressed to spoiled children or very rich people.

Pigs are highly intelligent and easily trainable animals, learning various tricks even faster than dogs. At 2-3 weeks old, piglets have already learned their own names and usually respond to them. As a matter of fact, they are the fourth most intelligent animals in the world only to chimpanzees, dolphins, and elephants.

Another unique feature of pigs is their unusual gait. When walking, these animals use only 2 toes on each foot, due to which they seem to walk on tiptoe.

Hippopotamus are distant relatives of pigs.

During a long period of time, China used to hold the largest population of domestic pigs around the world.

Pigs give out a shrill, high-pitched squealing noise of up to 115 decibels, which is 3 decibels higher than that of a supersonic Concorde.

In order to bring pigs together, farmers simply produce a yelling sound, to which they instantly respond.

As Winston Churchill said, “Dogs look up to a man. Cats look down at a man. Pigs look us straight in the eye and see an equal.”