Pig Gestation Period: How Long Are Pigs Pregnant?

When people look at pigs, they typically see dirty, sloppy animals. After all, don’t pigs like to wallow in mud? Don’t they eat whatever slop humans put in front of them? Actually, pigs only wallow to keep themselves cool, and many of them are discriminating eaters. Moreover, they make excellent parents. So, how many piglets can they have at one time, and how long are pigs pregnant? Find out this and much more below!

What Are Pigs?

Both wild and domestic pigs fall under the genus Sus in the Suidae family. They are even-toed, ungulate (hoofed) mammals with four toes on each foot. The scientific name for domesticated pigs is Sus scrofa domesticus. For wild boars, it is Sus scrofa. There are eight species of pigs with various subspecies and hundreds of breeds.

Domesticated pigs are found everywhere in the world except Antarctica. Pastures, farmland, and forests are their most common habitats. They thrive in temperate conditions that permit them to spend part of their time outdoors.

Wild pigs are highly adaptable and have managed to carve a niche for themselves in many habitats. These include grasslands, swamplands, temperate forests, rainforests, scrublands, and savannas. They have adapted to so many environments that in some parts of the world, like the United States and Canada, they are considered an invasive species.

Pigs vary quite a bit in appearance and size, depending on their species and breed. All pigs, regardless of their type, tend to be bulky in the body with short legs and large snouts. They come in several colors ranging from white, pink, gray, brown, and black. Some have spots or patterns. Most pigs have hairy bristles on their backs or snouts.

Most domesticated pigs fall between 100 and 700 pounds as adults. However, their size can vary widely between the different breeds, with some of the largest exceeding six feet in length. Wild pigs can also reach significant sizes. The largest is the African giant forest hog, which typically has a maximum length of 6 feet 6 inches. However, despite their substantial size, pigs do have some predators, including coyotes, wolves, bears, alligators, crocodiles, and big cats such as mountain lions.

What Do Pigs Eat?

As omnivores, pigs can eat almost anything, but not everything is good for them. Farmers feed domesticated pigs foods that give them energy and protein. For energy, pigs eat barley, wheat, and corn. For protein, they consume soybeans and canola meals.

Wild pigs are opportunistic eaters, meaning they will eat whatever is most convenient. Nuts, acorns, grass, roots, bark, truffles, and fungi form part of their diet. They may also eat crops like wheat, corn, rice, oats, potato, watermelon, and cantaloupe. Various insects, reptiles, birds, and small mammals are also acceptable, including eggs.

Social Behaviour

Pigs are highly social animals who form herds called sounders, both for companionship and protection. They also establish hierarchies. Members of the sounder express dominance through aggression and the choice of resting places. Wild pigs live in groups of several females and their offspring. Boars (male pigs) remain on their own except when mating.

Pigs are known as highly intelligent, social animals, and their snouts are extremely sensitive. Pigs communicate in a variety of ways. They communicate vocally by grunting and squeaking. They also use gestures like head tossing and ear cocking. Pheromones help them communicate using smell. Additionally, scientists have observed farm pigs expressing affection through “social nosing.” This may take the place of the grooming and licking behaviors found among other species.

Pig Reproduction

Female pigs reach sexual maturity at six to eight months, after which they can breed. Males usually reach sexual maturity at around six months of age. Domesticated pigs may mate and farrow at any time of year, though it is less likely in summer and early autumn. However, wild pigs generally breed in late winter and farrow in spring when conditions favor their young. Sows (female pigs) farrow (give birth to piglets) in nests.

Gestation Period

Pigs are pregnant for an average of 114 to 116 days. This comes to about three months, three weeks, and three days.

Sows show their first signs of pregnancy around their udders (milk rail). They swell toward the back while the teats drop toward the ground. When the sow is days away from delivery, a gentle squeeze of the teats will produce ready drops of milk. It may take up to 30 days after impregnation to begin noticing a change in a sow’s udder. The vulva will also begin to swell during this time.

The sow will generally get bigger and rounder as the pregnancy progresses. She may slow down and rest more often. Pregnant sows will not go into heat, but boars may still try to mount them. As the birth approaches, the sow’s appetite will increase dramatically. Often, once labor begins, the sow will begin gathering material for a nest. In domesticated pigs, this typically consists of gathering large mouthfuls of bedding, carrying it to their chosen spot, and making and remaking the nest. The nest can be quite deep, depending on the amount of material available to be gathered, and some sows bury themselves in it so that their head and shoulders are completely covered.

Litter Size

Domesticated sows usually bear an average of 7 to 8 live piglets per litter, though this number can be as high as 12 to 14. It is also not uncommon for sows to give birth to more piglets than they have teats.

Wild sows tend to have smaller litters, averaging 4 to 6 piglets. Again, this number might rise on occasion to as many as 12 piglets per litter.