Sweating like a pig is a derogatory comment, meaning one is sweating profusely and disgustingly. But, pigs don't sweat much; they wallow in the mud to cool off. So where did the expression "sweating like a pig" come from?
It's actually a reference to pig iron.
Pig iron is the intermediate product of smelting iron ore. It is the molten iron from the blast furnace and it has a very high carbon content which makes it very brittle and not useful except for limited applications. Pig iron is intended for remelting.
When pig iron is poured into molds it has to remain in them until it cools. They know the ingots (called pigs) are cool enough to transport when they begin to sweat...the air around it reaches the dew point, causing droplets to form on the metal's surface.
Like all warm-blooded mammals, pigs (not really a precise term...we mean swine. A pig refers to a young swine) need to maintain a correct body temperature. A pig's sweat glands are ineffective at cooling their body temperatures, and therefore, they wallow in water or mud.
Humans and some other mammals sweat. Humans have two types of sweat glands which produce different types of sweat. We have sweat glands all over the body and produce watery droplets which evaporate and cool the skin. This sort of sweating is uncommon in animals. Very few animals sweat to keep their bodies cool.
A second type of gland forms sweat by breaking off bits of cells rather than secreting a droplet and is granular and fatty. In humans, this is the smelly sort of sweat associated with our armpits. Most animals have this sort of sweat gland, but they are mostly concentrated around the face and mouth, and around the anus. They seem to serve to keep the skin soft and flexible. Dogs and cats have a large number of these sweat glands on their footpads. Horses sweat. Their sweat contains a type of protein which often causes it to froth. Hippos have red sweat that has some antibacterial properties.
Researchers from the National Institutes of Health have successfully transplanted hearts from genetically engineered pigs into baboons, potentially paving the way for pig-to-human organ transplants in the future.
Many of the pig’s biological systems are very similar to that of humans and if something works in a pig, then it has a high possibility of working in the human. A lot of the pig’s organs are 80 to 90 percent similar to that of humans. The cardiovascular system is a good match...a pig’s heart is about the same size and shape as a human heart. Pigs develop atherosclerosis the same way that humans do and they react similarly to myocardial infarction...or heart attack. We’ve been able to transplant pig heart valves into humans.
A pig's physiology of digestion and the metabolic processes in the liver are similar to humans so they are good for dietary studies and absorption studies of drugs. Pig kidneys are comparable in size and function to human kidneys and pig skin has been used in plastic surgery for decades because pig skin wounds heal similarly to humans. The insulin-producing cells in a pig’s pancreas are similar to humans’, so a significant amount of research on diabetes has been accomplished from studying pigs.
Tattoos are difficult to practice, but pig skin makes an ideal material for practice because it's very similar to human skin and relatively cheap.
By the 1950’s developments in technology made pigskin commercially viable product. Ever buy garments or shoes with a label proclaiming the product is "Genuine leather" or "Berkshire leather"? If so, it's probably pig skin.
Pigskin began to be used in 1852 as a more affordable substitute to goat leather because the qualities and appearance are similar. In the US it was used to make footballs until these were replaced with synthetic materials. It was also used a lot in bookbinding.
Pigs are rarely butchered just for their skin; it is usually a by-product of the food industry. Pigskin leather is usually artificially grained to give it a better surface texture and make it more aesthetically pleasing.
Pigskin is a desirable product because it's softer than most other leathers, tough pliable, flexible, withstands moisture without stiffening, resists abrasion, is strong, thin and durable. Plus it's breathable, water, oil and stain repellent. All those properties make it ideal for work gloves, wallets, shoes and even Louis Vuitton uses pigskin leather for their handbags.
Pigs are intelligent and they can, and do, eat almost anything. They won’t hesitate to cannibalize another pig nor eat humans.
Domestic hogs are not typically aggressive but there is some degree of danger associated with them. I used to work with a guy who had an uncle that was killed when he was attacked by a hog.
While they don't specifically go after humans, their teeth can chomp up bones like a piece of hard candy. In 2012, on a pig farm near Riverton, Oregon a 70-year-old pig farmer named Terry Garner was eaten by his hogs. Nobody knows exactly what happened. Was he attacked or have a medical emergency?
By the time a concerned relative arrived to check on him, apart from his dentures and some bloody scraps around the pen, there was nothing left...not even bones. Several of the hogs weighed in excess of 700.
His brother, 75-year old Michael Garner, told officials that one of the large sows had bitten Terry the previous year when he accidentally stepped on a piglet.
Cattle kill approximately 22 Americans per year nationwide and according to a 2009 study the animals deliberately attacked their victims in 75 percent of the cases. About one-third of killer cattle had a history of aggressive behavior. It is believed that pigs kill fewer people than cattle.
Livestock display an alarming ability to coordinate their attacks. A herd of cattle will form a circle with their butts facing the center of the circle, lower their heads and paw the ground. Of the cattle-related fatalities in the US between 2003 and 2008, about a quarter of them involved the animals ganging up on their victim. Pigs are also known to attack in a group.
If confronted by an angry pig or cow you should back away and get behind something. Carrying a big club would help, too...just in case. Personally, if I worked around pigs or cattle, I'd have a six-shooter handy.