Instruct: Given a question, retrieve relevant passages that can help answer the question.
Query: Are footballs really made of pig skin?
The first balls were made of natural materials, such as an inflated pig bladder, later put inside a leather cover, which has given rise to the American slang-term "pigskin". Modern balls are designed by teams of engineers to exacting specifications, with rubber or plastic bladders, and often with plastic covers. Various leagues and games use different balls, though they all have one of the following basic shapes:
The Skinny Pig is an almost hairless breed of Guinea pig. Skinny pigs typically have hair on their muzzles, feet, and legs, but are hairless over the remainder of their bodies. Some of them have a thin covering of fuzzy hair on their backs as well. A healthy Skinny has skin that is mostly smooth with some wrinkling around the legs and neck, the body is full with no appearance of spine or ribs. Skinnies can come in a variety of colours and patterns, such as Dutch, Tortoiseshell, Himalayan and many others. "Skinny" is the term used for hairless guinea pigs to describe the illusion of their visually thinner appearance, or coloquially referring to the exposed skin of the animal. The modern Skinny Pig breed originated with a cross between haired guinea pigs and a hairless lab strain. The hairless strain that it is most likely related to was a spontaneous genetic mutation that was first identified at Montreal's Armand Frappier Institute in 1978, in a colony of Hartley lab guinea pigs. In 1982 they were sent to Charles River Laboratories to be bred for laboratory use and are commonly used in dermatology studies today. They are an outbred strain that has an intact thymus and normal immune system.
Human skin is very similar to pig skin, therefore pig skin has been used in many preclinical studies. In addition to providing use in biomedical research and for drug testing, genetic advances in human healthcare have provided a pathway for domestic pigs to become xenotransplantation candidates
for humans.
By the end of the 19th century, the breed of pig seen in the northern counties of Ireland was of consistent type and differed from the crosses favoured in the south. A number of potential origins have been suggested for this breed. Up until the 1870s, the Berkshire pig had been the most popular breed in Ireland, but in the latter half of the century 'improvement' efforts were concentrated on white-skinned Yorkshire types, particularly the Middle White, and it is probable that the Ulster White was the result of such crosses with local strains. Some authors asserted that it had some ancestry from the "Old Irish" or "Greyhound Pig" landrace of earlier times. The latter had been a long-legged, coarse-haired pig with white skin, and it has also been suggested that the Ulster White was either the direct product of selective breeding of the Old Irish or of early 19th century crosses between it and the Berkshire.
Lisa, despite being a child prodigy, often sees herself as a misfit within the Simpson family and other children due to possessing an unusually high level of intelligence. She shows characteristics rarely seen in Springfield, including spirituality and commitment to peaceful ways, and is notably more concerned with world affairs than her life in Springfield, with her rebellion against social norms being depicted as constructive and heroic, yet she can be self-righteous at times. In "Lisa the Vegetarian", an increasing sense of moral righteousness leads her to disrupt her father's roast-pig barbecue, an act for which she later apologizes. Episodes often take shots at Lisa's idealism and virtue signalling. In "Bart Star", (season nine, 1997) Lisa, departs from her typically more genuine nature and apparently looking for a new cause to crusade over, defiantly declares that she, a girl, would like to join the football team. In the 1990s, it was considered odd to allow a girl to play football. However, when coach Ned Flanders reveals that several girls already play for the team, she hesitates and claims football is "not really [her] thing". She then expresses distaste about a ball made of pig's skin, but one of the girls informs her that their footballs are synthetic and that proceeds are donated to Amnesty International. Upset by being unable to gain moral superiority, Lisa runs off.
Though Delvoye started tattooing pig skins taken from slaughterhouses in the United States in 1992, he began to tattoo live pigs in 1997. Delvoye was interested in the idea that “the pig would literally grow in value," both in a physical and economic sense. He ultimately moved the operation to an Art Farm in China in 2004. The pigs have been inked with a diverse array of designs, including the trivial, such as skulls and crosses, to Louis Vuitton designs, to designs dictated by the pig's anatomy". In an interview with "ArtAsiaPacific's" Paul Laster, Delvoye described the process of tattooing a live pig, "we sedate it, shave it and apply Vaseline to its skin".
December 20 represents the starting day for traditional pig slaughter ("Tăiatul Porcului") ending on Christmas Eve. The householder himself or a hired skilled neighbor will carry out the entire job, starting early in the morning. Everywhere in the village can be heard the scream of pigs. It takes three to four men to drag out from shelter and put down the animal. The skilled butcher stabs directly the pig's heart with a long sharp knife, for a quick death without suffering. The corpse is left a few minutes for blood draining. Meanwhile, the householder will treat the men who helped him with a cup of home-made brandy ("țuică") or wine, preferably hot, thanking them for their help. After that, the pig's body will be cleaned and covered with straws. The pig's entire skin hair will be burned until the skin is cooked enough, all around. While cleaning and washing is done by pouring hot water, the skin is grated using knives, even bricks or simply tin cans, punctured with a nail. At this stage, the skin ("șorici") becomes eatable - fresh or slightly salted. Then the hooves are plucked and the body is placed with back on top. A cross sign is cut on pig's back and filled with salt. The housewife is incensing all over and everybody is praying God for food blessing. Only after this moment, the meat can be cut to be kept raw in salt, dried or smoked, or to be prepared using various traditional recipes and kept dried or smoked or even fried in the melted pig's fat. At the end, the householder prepares a meal of pork for those who helped him, this custom being known as "Pomana Porcului".
All these forms of pig farm are in use today. In developed nations, commercial farms house thousands of pigs in climate-controlled buildings. Pigs are a popular form of livestock, with more than one billion pigs butchered each year worldwide, 100 million of them in the USA. The majority of pigs are used for human food but also supply skin, fat and other materials for use as clothing, ingredients for processed foods, cosmetics, and medical use.
Skin Graft: This performance art installation appeared in the 2000 exhibition "Infatuation with Injury" organized by Li Xianting. In the exhibit, Zhu uses his own flesh as a canvas. Photos were shown of trunk of a quartered pig lying on a hospital bed. Zhu grafted a piece of his own skin onto a section of damaged skin from the pig. Two photos of this process appeared in the exhibit; one that showed the surgical process, and another which featured the artist sewing his own skin onto the pig carcass. Zhu stood by the exhibit and lifted his shirt to show the scar which stood as evidence of the procedure.
After being sacrificed, the hair of the winning pig is removed or the bristles shaved into patterns, and the skin is stretched across a metal frame. Further decorations are added such as placing a pineapple in the pig's mouth. The stretched skin, along with the carcasses or stretched skins of the other fattened pigs, are then paraded on a float. Many Holy pigs end up weighing over 800 kg whereas a normal pig would weigh only 120 kg.
Pig farming is the raising and breeding of domestic pigs as livestock, and is a branch of animal husbandry. Pigs are farmed principally to be eaten (e.g. bacon, gammon) or sometimes skinned.
Hairless guinea pigs are not significantly physiologically different than regular haired guinea pigs, although they need to eat more to maintain body heat. The optimal temperature range for a hairless guinea pig is , which is slightly higher than the optimal temperature range for the haired guinea pig.
Their skin has a similar appearance to human skin, but has a more rubbery texture. Their skin is quite vulnerable to sunburn, other injuries and fungal infections unless precautions are taken. Baldwin guinea pigs should be housed indoors and they are usually kept with nesting materials such as a blanket, fleece bag or small plastic or wooden house for heat conservation. Heating pads or other external heat sources may be needed when the weather is cold. 
Few varieties of hairless Guinea pig exist, the most prevalent breeds being the Skinny pig and the Baldwin. They are two separate breeds, with different genetic factors rendering them hairless. Hairless cavies in general need warmer accommodation and more energy-rich food to compensate for the loss of body heat. They are also susceptible to draught, drying of the skin, and skin infections without careful husbandry.
After running out of K-rations, they split up to search for food. Han discovers a wild pig in a thicket, which Kane captures and kills. While discussing how to cook it, someone suggests that they first skin it. Han asks if they have pigs in America and says you don’t skin a pig but rather roast it whole over an open fire. After doing so and enjoying a wonderful meal, they muse about how bright Han is for a child that they figure to be 9 or 10 years old.
The business fable of The Chicken and the Pig is about commitment to a project or cause. When producing a dish made of ham or bacon and eggs, the pig provides the ham or bacon which requires his or her sacrifice and the chicken provides the eggs which are not difficult to produce. Thus the pig is really committed in that dish while the chicken is only involved, yet both are needed to produce the dish.
The identification of human skin bindings has been attempted by examining the pattern of hair follicles, to distinguish human skin from that of other animals typically used for bookbinding, such as calf, sheep, goat, and pig. This is a necessarily subjective test, made harder by the distortions in the process of treating leather for binding. Testing a DNA sample is possible in principle, but DNA can be destroyed when skin is tanned, it degrades over time, and it can be contaminated by human readers.
The Philippine government reportedly requested changes to the film, due to the depiction of Philippine soldiers as cowards, which were denied. However the government later said they made no such suggestions.
In one scene Padre Rafael tells Dr. Canavan that the Moros are afraid of burial in a pig skin. In a later scene Dr. Canavan threatens Moro prisoner with this, and a pig skin is laid on the ground in front of the prisoner. This episode echoes a report in General Pershing's memoir "My Life Before the World War" that a Muslim fighter had been "publicly buried in the same grave with a dead pig". There is a related, but widely discredited, claim that Pershing had threatened to execute Muslim Moro prisoners with bullets dipped in pigs' blood. The historian Brian M. Linn wrote that it was unlikely that Pershing was involved in or had ordered others to commit religiously insulting acts, and that the episode in "The Real Glory" had probably fuelled the myth. This claim concerning bullets dipped in pigs' blood was referred to by Donald Trump in a presidential campaign speech in February 2016 and in a tweet following the terrorist attacks in Barcelona on August 17, 2017.
A pig scalder is a tool that was used to soften the skin of a pig after it had been killed to remove the hair from its skin. Because people rarely slaughter and process their own pigs anymore, pig scalders are seldom used for domestic use.
Kocsonya is a Hungarian meat jelly similar to aspic that is served as a chilled main course. It is traditionally made from pork products such as pig ears, pig tail, pig pettitoes, the front hand of pork, and pork skin. Spices that are added include red pepper, salt, black pepper, garlic, hot red pepper, and onion.
 is made from deep-fried pig skin with meat attached, but it can also be made from chicken skin. In the Caribbean coast, it is eaten along with , or boiled yuca at breakfast at home or at any time of the day at restaurants. It is eaten chopped as a stuffing in . In Córdoba, it is also prepared in . It is also part of , a typical dish of Antioquia.
In Mammola, an ancient tradition survives of making the serenity when you kill the pig, sung and played with accordion and guitar to honor the family. This special evening is celebrated with friends and family with the tasting of "frittole, obviously accompanied by a glass of wine and bread pizza" (corn bread), prepared during the day and cooked in the typical "caddàra. In other cultures, specifically ancient Greek, the pig skin's wrinkle count is used to predict the gender of a newborn. If the pig skin has an even number of wrinkles, the child is likely female. On the other hand, if the pig skin tallies an odd number of wrinkles, then the child is likely a male. 
Almost all of the pig can be used as food. Preparations of pig parts into specialties include: sausage (and casings made from the intestines), bacon, gammon, ham, skin into pork scratchings, feet into trotters, head into a meat jelly called head cheese (brawn), and consumption of the liver, chitterlings and blood (blood pudding or black pudding). This is also, technically, the case for all other mammals, although the demand is not really there.
The cooking process is communal and usually directed by an authority figure; the host is helped by friends or family. It usually takes four to eight hours to cook the pig completely; the pig is often started "meat-side" down, and then is flipped one time once the hog has stopped dripping rendered fat. Some practitioners clean ashes from the skin with paper towels or a small whisk broom before flipping the hog to help produce high quality cracklings from the skin.
The domestic pig, both as a live animal and source of post-mortem tissues, is one of the most valuable animal models used in biomedical research today, because of its biological, physiological and anatomical similarities to human beings.[85][86] For instance, human skin is very similar to pig skin, therefore pig skin has been used in many preclinical studies.[85][86] Porcine are used in finding treatments, cures for diseases, xenotransplantation,[87] and for general education. They are also used in the development of medical instruments and devices, surgical techniques and instrumentation, and FDA-approved research. As part of animal conservation (The Three Rs (animals)), these animals contribute to the reduction methods for animal research, as they supply more information from fewer animals used, for a lower cost.
Another version of the story says that his pigs became infected and diseased and that his search for food for the pigs brought him to Swainswick, where a farmer advised him to look for acorns on the far side of the river (possibly the Lam Brook at the bottom of the Lam valley). He came to a place where the pigs began to wallow in hot mud. To entice them out, he climbed an oak tree, collected some acorns and made a trail out of the mud. As the pigs came out, he scraped them clean and found their skin was cleansed and cured.