The domestic pig is an even-toed, hoofed mammal. Though it's an even-toed ungulate, the pig does not have a rumen. It belongs to the family Suidae and the genus Sus. The domestic pig is often called swine, hog or pig when distinguished from other members of the genus Sus. A group of pigs is called a passel, a team, or a sounder. It’s a versatile and intelligent mammal that humans have bred and raised for centuries. Domestic pigs are descended from wild boars native to Europe and Asia. Pigs were domesticated separately in Western Asia and China, with Western Asian pigs introduced into Europe, where they crossed with wild boar. They are highly adaptable creatures and can be found in many habitats, including forests, grasslands and even urban areas. It is one of the world's most widespread and economically essential livestock animals. Pigs are primarily farmed for meat production called pork but are also used for other purposes such as leather production and medical research. These animals' bones, hide and bristles are also used in products. The miniature breeds are kept as pets. Its significance in various cultures and its remarkable versatility make it an essential part of our agricultural systems.
Domestic pigs come in a wide range of sizes, colours and patterns. They can weigh anywhere from 45 kg to over 350 kilograms and their body length ranges from 3 to 6 feet including the tail, depending on the breed. Their bodies are large with a stocky build, supported by short legs that end in cloven hooves. Compared to other artiodactyls, a pig's head is relatively long and pointed. They have a distinctive snout that allows them to dig efficiently in search of food and roots. Most even-toed ungulates are herbivorous but pigs are omnivores, like their wild relative. These animals possess a well-developed sense of smell and hearing, which they use to communicate with each other through a wide range of vocalizations. Pigs grunt and make snorting sounds. They have also been observed displaying problem-solving skills and exhibiting curiosity towards new objects or situations in their environment.
Hog, swine or pig
Sus scrofa domesticus or Sus domesticus
20-38 inches in height and 35-71 inches in length
45-350 kg
12-18 years
The scientific name of the domestic pig, "Sus scrofa domestic", holds significant importance in understanding its biological classification and evolutionary history. The first part of the scientific name, Sus, refers to the genus to which pigs belong. This genus includes various wild boars and pig-like species found across different regions of the world. The second part of the name, scrofa domestica, specifies that this particular species is a domesticated form of the Eurasian wild boar (Sus scrofa). It emphasizes how pigs have been altered through generations of selective breeding by humans. It belongs to the order Artiodactyla, suborder Suina (with hippos) and is derived from the subfamily Suinae of the Suidae family. The pig is often called swine, hog or domestic pig when distinguished from other members of the genus Sus. It was domesticated approximately 5,000 to 7,000 years ago.
Pigs are fascinating and the most versatile animals humans have domesticated. There are a lot of misconceptions about pigs but these facts about pigs will help people to see them differently.
The appearance and anatomy of the domestic pig showcase its unique characteristics as a highly adaptable and intelligent animal. With its distinctive appearance and unique anatomy, the domestic pig has become a familiar sight on farms around the world.
Domestic pigs are typically large, round stout-bodied, short-legged, thick-skinned omnivorous mammals. Their bodies are covered in bristly hair that can vary in colour from black to white or even spotted patterns. Their hooves have two functional and two nonfunctional digits. One of the most notable features of the domestic pig is its long and flexible snout. The elongated shape is well-adapted in search of food. Apart from their snouts, pigs also display other characteristic facial features such as two pairs of small keen eyes situated on the sides of their large heads that offer excellent peripheral vision while grazing or foraging and upright ears that can be either floppy or erect depending on the breed. Its colouration can range from pink to black, with some pigs having spots or patches on their skin. These animals are relatively large representatives of even-toed ungulates. Additionally, they are noticeably larger and slower than the wild pigs, from which they are bred. Domestic North American pigs originated from wild stocks still found in European, Asian, and North African forests.
In terms of anatomy, one notable feature is the pig's snout which is not only an essential sensory organ but also serves as a tool for rooting up the ground and digging while searching for food. They possess an acute sense of smell due to their elongated snouts and well-developed olfactory system. Pigs also possess strong teeth adapted for tearing through vegetation or even bones if necessary. They have four toes on each foot that end in cloven hooves, with two larger ones that come into contact with the ground while walking or running. Their bodies are also supported by a robust skeletal structure composed of bones and joints designed for endurance and stability. Internally, pigs possess complex digestive systems that allow them to process different types of food efficiently.
In terms of size, adult domestic pigs can vary greatly depending on their breed and purpose. On average, they can reach a height of 24 to 34 inches at the shoulder and have a length ranging from 3 to 6 feet. Their weight can range from as little as 100 pounds for miniature breeds up to over 770 pounds (45 to 350 kilograms) for large commercial breeds.
Originating from wild boars in Eurasia, the domestication of pigs occurred thousands of years ago. These animals have adapted to a variety of habitats due to their resilience and omnivorous nature.
In terms of habitat, domestic pigs are incredibly versatile creatures. Domestic pigs prefer areas with ample vegetation and access to water sources such as rivers or ponds. Having water nearby gives them plenty of chances to drink and cool off during the day. Whenever they have the chance, all pigs wallow in mud as it helps them regulate their body temperature during hot weather and discourages parasites. In more developed regions, they are usually kept in controlled environments such as barns or pens with access to outdoor spaces for grazing. On the other hand, in less industrialized areas, they may roam freely through forests, grasslands, wetlands, savannas, scrublands and even urban areas including temperate forests as well as tropical rainforests. Most pigs prefer to live in a warmer climate, an area with a certain temperature and weather conditions. Even though pigs prefer this type of climate, many farm-raised pigs live in cooler climates and survive just fine. Additionally, domestic pigs have successfully adapted to different climates ranging from hot and humid tropical regions to cold and harsh northern landscapes. All of these habitats have two things in common though: water and vegetation.
Domestic pigs are widely distributed around the world. They can be found on farms and homesteads across every continent except Antarctica. Distribution-wise, the presence of domestic pigs is heavily influenced by human activity. The highest populations can be found in regions where pig farming is prevalent for meat production purposes. There are hundreds of breeds of domestic pigs that live from the US to Australia to Europe to Asia. The American Yorkshire Pig, the most common pig in the US, is found in nearly every US state and used for meat across the country.
When it comes to domestic pigs, there are several common types or subspecies that enthusiasts and farmers often encounter. Domestic pigs are categorized according to three basic types:
The most common domestic pig is the Yorkshire pig, which is renowned for its tender meat. Originating from England, these pigs are typically Large White and are known for their excellent meat quality. Yorkshire's pigs possess a long body with a straight back and large hams with a strong build, making them highly valued in the pork industry. It is the most-recorded breed of swine in North America, Yorkshires are white with erect ears. They are found in almost every state, with the highest populations being in Illinois, Indiana, Iowa, Nebraska and Ohio. Yorkshires are known for their muscle, lean meat with a high proportion of low backfat.
Domestic pigs are commonly known as approachable, loyal and highly intelligent creatures. These animals are relatively large representatives of even-toed ungulates. Additionally, they are noticeably larger and slower than the wild pigs, from which they are bred. Pigs are found and raised all over the world and provide valuable products for humans, including pork, lard, leather, glue, fertilizer, and a variety of medicines. Most pigs raised in the United States are classified as meat-type pigs, as they produce more lean meat than lard and their fat is used in cooking.
Pigs can be found almost anywhere in the world, except Antarctica. There are hundreds of breeds of domestic pigs that live from the US to Australia to Europe to Asia. The American Yorkshire Pig, the most common pig in the US, is found in nearly every US state and used for meat across the country.
These animals maintain an omnivorous diet, which means that they consume food of both animal and plant origin. Pigs are happy to eat plants, fungi, fruit, insects, crustaceans and small vertebrates.
Domesticated pigs enjoy a wide variety of foods including vegetables, fruits, nuts and seeds. Unlike wild pigs, domestic pigs do not have to forage for food. Most domestic pigs alive today are raised on factory farms. On these farms, pigs usually eat a specially formulated diet containing different grains and cereals.
Good pig feed contains sufficient energy, protein, minerals and vitamins: rice bran, broken rice, maize, soya beans, cassava and vegetables. The bulk of their diet comes from corn and soybeans. Commercial pigs primarily eat just two crops: corn for energy and soybeans for protein. They also eat other grains like wheat and sorghum. Farmers feed pigs a high-quality, grain-based diet consisting mainly of crops such as barley, wheat and corn which provide pigs energy, soybeans and canola meal for protein. Farmers add vitamins and minerals to the feed of newly-weaned pigs for optimum nutrition. It is recommended that pigs are provided with a complete (manufactured) diet or a home-mixed diet that has been formulated to meet the pig's needs. Clean, fresh water is an essential part of a pig’s diet.
A domestic pig eats nearly 4 per cent of its body weight each day. That's why they need a proper and balanced diet (for successful piggery) such as carbohydrates, vitamins, fats and proteins.
They are inquisitive animals and have complex needs that should be met by their environment on a farm. Pigs are highly intelligent, inquisitive, adaptable, and social animals that learn quickly. In many learning tests, they can outperform dogs.
They are omnivores, having a varied diet, primarily high in fibre. Typically pigs spend much of their time foraging and rooting for food. Pigs make nests for sleeping and huddle together for warmth. They are highly intelligent, social animals, displaying elaborate maternal, communicative and affiliative behaviour. Male pigs of any age are called boars while female pigs are called sows. Boars are often solitary while sows construct elaborate nests before giving birth. 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.
Domestic pigs (Sus domesticus) are commonly known as approachable and loyal creatures. Pigs prefer to live in stable families or small groups, they can be aggressive to each other if unfamiliar animals are mixed. Pigs are clean animals, if they're given appropriate housing, they will use one particular area for dunging, keeping their lying/sleeping area clean. Pigs spend the majority of their time resting or lying. On average, grow-finish pigs spend 75 to 85% of their time lying and 5 to 10% eating, with the remainder of their time involved in other activities such as walking, sitting, rooting/nosing and drinking. In intensive farming, pigs are typically fed twice a day with unvaried uniform feed which usually takes them only about ten minutes to eat. Around midday, pigs like to rest for several hours or dedicate themselves to extensive bathing, wallowing and rolling around.
The reproduction process in domestic pigs is an intricate and fascinating journey. From mating to birth, these intelligent animals exhibit remarkable behaviours and physiologies that contribute to successful reproduction. There are two major categories for the breeding of domestic pigs: natural and artificial insemination. Most outdoor pig producers use natural breeding. Domesticated pigs are considered "non-seasonal polyestrous" which means, they can be bred year-round and will cycle every 21 days regardless of the season. This stage of a pig's life cycle lasts approximately two years, so long as a farmer hasn't slaughtered it for its meat by then. A pig's intended meat can be killed as early as four months old. If they are not successfully bred, a non-pregnant female pig is called a sow.
All domestic female pigs can breed about twice every year. Female pigs can have litters of their own by five or six months of age. Most males or boars are sexually mature for breeding around 12 months of age while female pigs known as sows reach sexual maturity at 3 to 7 months of age and then come into estrus every 18 to 24 days. Sows display characteristic signs of estrus or heat, such as restlessness and vocalization. During mating season, boars compete for the attention of the show by displaying aggressive behaviour like head-butting and pushing each other. The dominance hierarchy is established within the group until one boar successfully mates with the receptive female. The gestation period for pigs is approximately three months, three weeks and three days, roughly 114 days in total. A sow expelling piglets before 109 days should be classed as an abortion and any piglets born between 109 and 112 days as a premature farrowing. When a sow is ready to give birth to her piglets, she will create a nest with hay or straw to provide a safe environment for her newborns. Sows usually give birth to a litter per year consisting of several piglets at once, although 2 litters per year are possible and young may be born at any time of the year. Typical litter size can range from six to twelve piglets, although larger litter have been recorded.
The newborn piglets are incredibly small, adorable and fragile, weighing around two pounds each and are born with open eyes, very little hair and fully developed senses. Litter size depends upon the age of the sow, nutritional intake and time of year. They rely heavily on their mother's milk for nourishment during the first few weeks of life. As they grow older, they gradually transition to solid foods such as grains and vegetables. The piglets meant for sale as breeder stock must be appropriately reared. Male piglets not selected for breeding should be castrated preferably at 3-4.
When it comes to the lifespan of domestic pigs, there are a few factors to consider. On average, the lifespan of a domestic pig ranges from 12 to 20 years, depending on their breed and living conditions.
Pigs are prey animals. They can't turn their heads and neck like a dog. Pigs are big in stature but they cannot fly. Common sense tells people that they can't win a battle with a dog who is a predator by nature.
Though predators such as wild cats, dogs, coyotes, bobcats, foxes, mountain lions, black bears, crocodiles and large birds like golden eagles may opportunistically prey upon immature pigs, predators such as bobcats and coyotes may occasionally take piglets or weakened animals but are not large enough to challenge a full-grown boar. Predation of piglets by red foxes is a significant risk for outdoor/free-range pork producers but is often difficult to quantify. Man has domesticated varieties of pig species as food and for use as raw materials for industries.
When feeling threatened, pigs will freeze, flee or fight. Pressuring a pig that is feeling threatened will stress the pig which could cause injury to both the pig and handler. A handler should move calmly and position their eyes downward to seem less like a predator to calm the pigs down.
With around 1 billion individuals alive at any time, the domesticated pig is one of the most numerous large mammals on the planet. The first case of ASF in a domestic pig population in Serbia was confirmed in 2019 in a backyard population. Today, outbreaks in wild boar and, more importantly, in domestic pigs are still occurring, although government measures for ASF prevention are in place. In 2022, there were over 784 million pigs worldwide, increasing from around 750 million heads in the previous year. China was home to more than half of the global pig population.
India's total livestock population was found to be 535.78 million, showing an increase of 4.6% from the previous 2012 livestock census. 3 Distribution of pig population across the country is not uniform, for instance, this k population of pigs is recorded in the eastern (2.8 million) and north-eastern (4.5 million) states; the highest population is in Asom (2 million), followed by Uttar Pradesh (1.35 million), West Bengal (0.82 million), Jharkhand (0.73).
Pigs were one of the first animals to be domesticated. They are found and raised all over the world and provide valuable products for humans, including pork, lard, leather, glue, fertilizer and a variety of medicines.
Domestication of pigs began around 9,000 years ago in different regions across the globe. This time humans corralled a few wild boars and separated them from their fellows. This process involved selectively breeding wild boars with desirable traits such as increased docility, meat quality and fertility. Breeding them for favourable traits like tameness, size and meatiness, as a result, various breeds with distinct features emerged over time. They developed the domesticated oinkers that we see all over the world today. Pigs were first domesticated in the Near East, a region roughly corresponding to the modern Middle East. Today, there are hundreds of pig breeds worldwide that vary in size, coat colouration, body shape, ear type (erect or floppy) and overall temperament.
Domestic pigs, scientifically known as Sus scrofa domesticus, belong to the family Suidae within the order Artiodactyla and are most often considered to be a subspecies of the wild boar, which was given the name Sus scrofa by Carl Linnaeus in 1758. However, in 1777, Johann Christian Polycarp Erxleben classified the pig as a separate species from the wild boar. They share this family with other pig-like animals such as warthogs and babirusas. There are several different genera and species but all domestic pigs fall under the genus Sus. These intelligent mammals have a fascinating evolutionary history that dates back thousands of years. The classification of domestic pigs is based on their physical characteristics, behaviour, and genetic traits.
This genus includes not only domestic pigs but also wild boars found in different regions across Europe, Asia and Africa. The domestic pig originates from the Eurasian wild boar (Sus scrofa). We have sequenced mitochondrial DNA and nuclear genes from wild and domestic pigs from Asia and Europe. Clear evidence was obtained for domestication to have occurred independently from wild boar subspecies in Europe and Asia.
Pigs have genetic and physiological traits similar to humans, which make them one of the most useful and versatile animal models. Owing to these similarities, data generated from porcine models are more likely to lead to viable human treatments than those from murine work.
Pigs love human company and enjoy attention, tummy rubs and scratches. In general, they are very friendly animals, but they can become territorial, so keep an eye on territorial behaviour and discourage this while the pigs are young. Pigs can be easily trained in much the same way as dogs.
In terms of their relationships with humans, pigs are victims of their success. Even more than wolves, they are highly adaptable and generalized omnivores, which means that they have a range of possible relationships with humans that is perhaps wider and more complex than for most other animal species.
The conservation status of domestic pigs is a matter of increasing concern in today's world. These animals, which have been an integral part of human societies for thousands of years, are now facing numerous threats to their survival. From habitat loss and fragmentation to disease outbreaks and genetic erosion, the challenges faced by domestic pigs are multifaceted and complex.
One significant threat to the conservation of domestic pigs is the loss of suitable habitats. As human populations continue to expand, forests and grasslands are being cleared at an alarming rate to make way for agriculture and urban development. This destruction not only eliminates essential feeding grounds for pigs but also disrupts their natural breeding patterns. Moreover, habitat fragmentation leads to increased isolation among pig populations, reducing their genetic diversity even further.
In addition to habitat loss, domestic pigs are highly susceptible to various diseases that can decimate entire herds.
Domestic pigs, wild pigs and feral pigs may sound similar and all belong to the same family but their behaviours and characteristics differ significantly. There are many subtle differences when it comes to identifying feral pigs, wild boars and domesticated pigs.