Pigs do not sweat, but have sweat glands DLX2 PS

Smelling Like a Pig: Do Pigs Sweat? How Pigs Cool Themselves

Pigs are iconically represented as wallowing in the mud, but that’s because pigs don’t sweat the same as people and have to cool down differently. Summer’s approaching so one of the projects I’m working on is ensuring our shade canopies are in place for our pigs.

The other day, one of my friends asked me about pigs and how they sweat. Pigs are fascinating in how they’ve learned to cope with heat.

Do pigs sweat? Pigs sweat very little because they have few sweat glands. They sweat so little that pigs are considered not to sweat. Their sweat glands don’t respond to thermoregulatory cues like human glands. Pigs cool themselves through means other than sweating and can become overheated very quickly in the heat if they don’t have access to shade, mud, or water.  

Feel free to skip to the area that interests you the most!

The Science of Pig Sweat and How Pigs Cool Themselves

Pigs have some sweat glands, but their glands don’t reduce the pig’s internal body temperature. This makes cooling off in hot weather difficult.

On the contrary, when hot, some animals and humans secrete sweat, a mixture of about 99% water and 1% other compounds such as sodium chloride and proteins. Sweating helps regulate our internal temperature so we don’t get too hot on sunny days or while exercising.,

But that isn’t the only interesting things about pigs and sweating that you should know. And, it leads to a few other important questions. Keep reading to learn more. 

Pigs have a thick layer of subcutaneous fat that insulates their body. This layer is great in winter but doesn’t help much when cooling themselves down in hot weather. 

One of the best ways for a pig to cool down is by cooling down their core temperature. To do this, pigs need access to plenty of cool drinking water (preferably water at a temperature under 50℉ ). 

Help Your Pig Stay Cool During Hot Weather

Try not to feed your pig any food high in fiber during hot spells (also make their portions slightly smaller). They use more energy to digest the food, which increases their internal body temperature. You may also find that your pig chooses to eat less when they’re feeling hot.

If a pig feels hot, it’ll instinctively search for a shady spot to escape the sun. The pig will root around and remove any leaves and twigs so it can get to the damp earth. It will sprawl out to ensure that most of their skin comes into contact with the cooler ground. 

Ensure trees or shaded structures are available for them to hide under. You may notice your pig breathing deeply and at a fast rate. Your pig is trying to cool itself down by panting (known as thermic polypnea). This method is effective. However, a pig’s lungs are pretty small, so they can only pant for a short period before they get tired. 

Another way you can assist your pig is by providing tubs of shallow water for them to wallow in or putting on the sprinkler system to make mud and spray them down with cool water. Pigs are smart and will find a way to tip over their water source to make a wallow. 

Top Tip: If your pigs make their own wallow, clean it out often, as pigs often poop and pee in the mud, which can eventually cause an unpleasant cesspool of bacteria that multiplies due to the heat.

Purposes of pig sweat glands are minor compared to other cooling methods DLX2 PS

Do Pigs Sweat: 4 Purposes of Pigs Sweat Glands

Two types of “sweat” glands (also known as sudoriferous glands) are present in pigs. The apocrine and eccrine glands. These two glands secrete liquid but not for the evaporative cooling down of the pig’s body or for producing sweat.

These sweat glands are found near the pig’s hair follicles, just under the skin’s surface, and on the pig’s snout. It’s also important to note that pigs have bristles of hair covering their bodies. This would make it difficult for the sweat to evaporate if pigs could sweat. 

It seems pointless that a pig has apocrine sweat glands, as they cannot use them to create sweat (kind of like an appendix for a human). Let’s take a closer look at the purposes of pigs’ sweat glands: 

1. Pigs Sweat Glands Assist with Mating

One of the main functions of a pig’s sweat glands is for chemical communication to take place between male and female pigs. The female pig’s gland secretes pheromones (an odorous scent) that notifies and attracts the male when she’s ready to mate. 

These secretions occur seasonally as the pigs come into heat. 

2. Pigs Sweat Glands are Used to Mark Territory

Male pigs also secrete an odorous scent from their sweat glands that is used to mark their territory. Marking is done by rubbing against objects. The secretion is also used to “call” other male pigs over a long distance. 

3. Pigs Sweat Glands Keep Them Cool

Pigs have very few functional sweat glands; because they have hair, any moisture that forms cannot evaporate. However, the apocrine sweat glands still secrete a substance that can cool the pig down slightly but not nearly enough to cool them down completely. This is known as thermoregulation.

4. Pigs Sweat Glands Keep Their Skin Moisturized

The apocrine glands also help to keep a pig’s skin moisturized. These glands secrete a thick oily substance that lubricates and moisturizes the pig’s hair follicles, which helps prevent the pig’s skin from drying out.

Pigs have sweat glands but difficult to cool themselves in hot weather DLX2 PS

Pigs Sweat Glands Location

The coils of the sweat glands are found in the hypodermis. This is the fatty layer of skin where the hair follicle roots are found. These sweat glands, which include carpal organs, are also found on the pig’s lips and snout.

Do Pigs Sweat on the Inside? Pigs don’t sweat on the inside (or the outside). However, they do use thermoregulatory mechanisms to help cool themselves down, such as wallowing in mud, panting, or lying on a cool surface. The fact that pigs can’t sweat externally or internally is why keeping your pig cool is essential.

Do Pigs Sweat Through Their Feet? Unlike dogs, pigs don’t sweat through their feet or anywhere else on their bodies. A pig’s limited sweat glands are found in the fatty layer of skin where the hair follicles and hair roots are located. These glands are also found on the pig’s snout and lips.

How Do Pigs Handle Heat Stress Since They Can’t Sweat?

Being unable to sweat poses quite a problem for pigs, as they can’t rely on their sweat glands to produce enough sweat to cool them down. That’s why pigs rely on thermoregulation, which is how their bodies maintain a suitable internal temperature between 101.5℉ to 102.5℉. Temperatures higher than this can lead to heat stress and heat stroke. 

Pigs thermoregulate by panting or taking cover in shady areas.

Pigs also seek shade, dig into the earth, wallow in mud, and roll in water to help handle heat stress.

Top Tip: If your pig is suffering from heat stress, help them to cool down with vinegar towels and check their temperature every 15 minutes with a rectal thermometer.

Let’s take a closer look at some effective ways that pigs regulate their body temperature:

Why Do Pigs Wallow In The Mud?

Pigs wallow in the mud because of their shortage of sweat glands as a means to stay cool during the hot months. The mud keeps pigs cooler because the water in mud evaporates at a much slower rate than water does by itself. 

That means that pigs can stay cooler longer. But, it has another purpose: It helps them protect their pale skin from getting sunburned.

But that’s not all. 

Pigs may wallow for other reasons as well. Wild pigs are often seen wallowing in the mud even in cooler temperatures. Many believe this helps rid them of parasites such as ticks and lice so it helps keep them healthy as well.

Just because pigs wallow in the mud doesn’t mean they’re dirty animals. In fact, pigs are considered fairly clean. When given enough space, pigs will designate a “bathroom” away from where they eat, drink, and live. 

They will also clean up the area by eating food that may have been spilled. They are considered one of the cleanest farm animals.

Pigs handle heat stress by wallowing in the mud DLX2 PS

Pigs Slow Down To Cool Down

When a pig is feeling hot, they start to slow down. Instead of foraging and running around their living environment, they are often seen lying in a shady area. This is so they don’t exert themselves further, which helps slow down heat production in their body.

Pigs will also eat less, which helps slow down their metabolism (which uses energy and results in further heat production).

Top Tip: If your pigs have access to a forest area that produces plenty of shade, consider moving some of their food to the area. They’ll be able to eat without getting burnt by the sun’s harsh rays.

Pigs Use Radiation To Lower Body Temperature

Pigs can also get rid of body heat through radiation (not the toxic kind). Radiation is a process where the pig increases blood flow to their skin, which decreases blood flow to their internal organs and digestive and reproductive tract. 

This puts far less stress on the pig’s body, which helps cool the pig down internally and helps the pig lose some of the heat. In a nutshell the pig dilates their blood vessels (vasodilation) and lowers their blood pressure. 

Pigs Root To Chill

Another way that pigs regulate their temperature is by rooting. Instead of digging a hole near water to wallow in, a pig will look for a nice shady spot, preferably in an area with soil (not cement). Once the pig has chosen the spot, they begin rooting. When a pig roots they nudge, or push plants, leaves, and debris away from an area using their snout. 

Once the area is cleared and they’ve exposed the cool damp soil, they lie down and let the earth cool them down. Pigs also root for comfort.

Let’s recap. Pigs roll in the mud for 3 main reasons. 

  1. The mud helps to cool their skin off since pigs can’t sweat enough to keep their bodies cool during the heat of the day. 
  2. The mud protects their skin from getting sunburned
  3. The mud helps to clean their skin from mites, parasites, and other pesky, itchy bugs
Pigs sweat glands location DLX4 PS

 Why Are Pigs So Dirty?

Pigs are considered dirty because they love to roll in the mud. However, consider that dirty is not the same as germy. Disease, germs, and infection of parasites occur more often when feces is combined with a pig’s food. Pigs avoid this type of dirty as much as possible. When pigs are confined to small areas, they will make a mess of their slop and waste.

But, pigs are not naturally filthy. When given enough space, pigs will keep their food and waste in separate parts of the pen. They will not roll in their feces or eat it. This helps pigs stay clean and free them from many parasite issues.

Pigs prefer clean food, plants, and bugs. However, their strong appetites compel them to eat nearly anything that is provided to them. If they cannot forage for plants, bugs, and other healthy foods, their strong hunger will compel them to eat nearly anything. Even though they will eat the slop of your table, rotten food, and other waste food, it isn’t usually the food they prefer.

People also assume pigs are slobs because they like rolling in the mud. This isn’t a sign of filthiness as much as a sign of heat. Pigs protect their sensitive skin from the sun by coating it with mud. The mud also helps to keep them cool in the summer.

How Do Pigs Get Rid of Toxins? 

Pigs get rid of toxins in their bodies through two main organs: the liver and the kidneys. The liver detoxifies the pig’s blood and converts the toxins into urea which passes into the kidneys. The kidneys filter out toxins and waste, which are then passed out of the body through their urine. Pigs also get rid of toxins when they salivate or defecate.

Does Pork Have Toxins?

We’ve established that pigs don’t really sweat. Because of this, many believe there are high concentrations of toxins in pork. 

Is Pork A More Toxic Meat To Eat Than Other Meats? 

Pork is not more toxic than other types of meat including beef and chicken. Pork can spread some parasites if eaten raw, but so can other types of meat. Beef often spreads ecoli and chicken spreads salmonella. When eaten fully cooked, pork is safe to eat.

Pork is not more toxic because pigs have few sweat glands. In fact, chickens have no sweat glands at all and cows have few sweat glands. Other mammals simply do not sweat in the same capacity as humans.

A pig’s liver and kidneys remove far more toxins from the body than sweating does. The primary purpose of the liver and kidneys is to remove toxins from the body and to excrete them. These organs filter out any excess toxins that may have gotten inside their bodies. The liver detoxifies and cleanses the blood. 

The kidneys filter waste materials from food and balance the blood. It also removes excess minerals from the bloodstream. Pigs have both a liver and a kidney. 

3 Reasons Pigs Are Not More Toxic

  1. Pigs have livers and kidneys, whose primary function is to remove toxins from the bloodstream and from the food consumed 
  2. Chickens have no sweat glands. Cows have no functioning sweat glands. So by comparison, pigs have fewer sweat glands than other popular meats eaten. 
  3. Humans, with the most sweat glands of any mammals, don’t sweat out parasites either, showing that sweating doesn’t help remove worms. 

If a pig does have worms or other parasites your best option is to have them see a vet where they can be dewormed, just like a cat, dog, or other animals.

And, your safest practice when eating any meat is to thoroughly cook it so that any parasites or germs (think e coli) can be killed before it is consumed. 

Pork doesn't have toxins than other types of meat DLX2 PS

Why Don’t People Eat Pork?

There are many reasons people choose not to eat pork. 

  • Religion – In many cultures and religions, pork is seen as unclean. Judaism and Islam believe it is a command not to eat pork. Because of that commandment, many people look for other reasons for pork to be unclean, even if those reasons have no basis in science. Other religions may worship animals or are vegetarians.
  • Vegetarian – Many people around the world identify themselves as vegetarian or vegan. This means they don’t believe in eating meat. Some feel it is inhumane to kill animals for food. Others may feel that they can get all the nutrients they need, including protein, from plants. Others don’t have a pallet for meat. 
  • Moral: Other reasons include but aren’t limited to how the pigs are treated on the farms, big corporations my run those farms, and how employees are treated.

Are Pigs The Only Animals That Don’t Sweat?

Pigs are not the only animal that doesn’t sweat much. Relative to their body mass, cows sweat very little. Chickens don’t sweat, but raise their wings and pant to get cooler. Goats primarily cool down through their horns. Fish don’t sweat. Elephants and rabbits don’t sweat. Each animal has a different way of cooling down.

AnimalDoes This Animal Sweat?
CowsYes, but cows sweat much less than humans relative to body mass
ChickensNo
Goats Goats sweat in their mid-section, but primarily cool themselves through other means
FishNo
RabbitsNo
PigsYes, but pigs sweat very little

Do Pigs Sweat FAQs

Pigs don’t sweat like horses or apes, but they have thermoregulation mechanisms to cool their bodies down, such as panting, wallowing in a mud bath, and slowing down any physical activity. 

Do pigs have pores?

Pigs have pores (small openings containing hair follicles) in their skin, but these pores don’t release sweat. Oil is secreted from the apocrine glands through the pores onto the pig’s skin to help keep their hair and skin moisturized and lubricated. These pores secrete sebum and not sweat like the pores on humans or horses do.

Do pigs sweat milk?

Pigs don’t sweat milk. Female pigs have mammary glands which produce milk to feed their piglets. A female pig has between 8 and 16 nipples that the piglets must suckle on to stimulate the milk “let down.” The milk only flows for around 15 seconds and does not pass through the sweat glands.

What Kinds Of Meat Comes From Pigs?

Pigs are found in most parts of the world making them one of the largest meat sources. Pork is now considered “the other white meat” largely because it is a healthier alternative to red meat such as beef. Some cuts, such as pork chops, are even healthier than chicken thighs. Pigs provide us with many different cuts of meat including bacon, sausage, ham, roast, ribs, and pork chops.

These cuts of meat can be a healthier alternative to its beef counterpart. You could try substituting pork chops for steak or cooking a pork roast instead of a beef roast. 

Where does the expression “Sweating like a pig” come from?

The expression “sweating like a pig” has nothing to do with the farm animal since they don’t really sweat. It refers to pig iron. When smelting the iron,  blacksmiths used molds that looked like piglets suckling their mother, where it got its name. 

After pouring the iron into the molds the metal would be too hot to touch. Blacksmiths would know when it cooled enough to touch when the iron started “sweating”, forming water droplets on the surface of the metal.

Conclusion

So now you know pigs have sweat glands but don’t actually sweat. These intelligent animals have amazing methods in place that they use to help them regulate their own body temperature.

The next time you see a pig enjoying a roll around in the mud, you’ll understand that they don’t just wallow in mud for fun or pant for attention. These are some of the most effective ways that they can cool themselves down. 

Ensure your pigs can access fresh water, sheltered areas, and places to enjoy a good old mud bath.

References

Research Gate The Genetics of Thermoregulation in Pigs: A Review

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