12 Ailments Humans And Animals Share


Humans aren't as different from the rest of the mammal world as we’d sometimes like to think. We’re not the only animals that get acne as youngsters, or suffer from allergies during the spring. Humans can even pass along some of their illnesses to their pets. Here are 12 familiar ailments that you might not know your pets can suffer from, too.

1. Acne

It turns out dogs, cats, and horses have their own skin struggles. In horses, the issue is most often caused by friction from saddles and harnesses, but it tends to strike short-haired dogs when they’re young and going through their awkward-teen phase, just like in humans. Cat pimples are a lifelong issue. The pores around a cat’s chin can become clogged with sebum, an oily substance that keeps the skin from drying out, resulting in blackheads, pimples, and overall inflammation. To prevent feline acne, vets recommend a pretty simple change: stop using plastic bowls, which can irritate cats’ skin. 

2. Hay Fever 

Dog and cat dander may be responsible your own sniffles, but your furry friends can also fall prey to allergies. Pollen and seeds can cause respiratory issues or skin problems such as redness and irritation in dogs and cats. You aren’t the only one suffering in spring. 

3. Asthma

Image Credit: Claire via Flickr // CC BY-NC-SA 2.0

Vets estimate that as many 800,000 American cats suffer from asthma. Cat owners can use inhalers similar to those used with babies to help their cats breathe more comfortably. Horses, too, can have an asthma-like condition called chronic obstructive pulmonary disease that causes their airways to narrow. Though anti-inflammatory medications can be delivered orally, equine asthma can also be treated with awesome giant inhalers like this.  

4. Addison’s Disease

President John F. Kennedy may be the most famous human to suffer from this disease, which affects the adrenal glands. It can also strike dogs, and in rare cases, cats. Addison’s prevents the adrenal glands from producing the hormones necessary for bodily function. This can upset the body’s natural balance of electrolytes, such as potassium and sodium, and cause weakness and irregular heartbeats. Because it affects the production of cortisol, the hormone released in response to stress, these symptoms worsen when the dog (or human) is stressed out. 

5. HIV

Up to 3 percent of U.S. cats are infected with feline immunodeficiency virus, the cat equivalent of HIV. The virus is largely spread through cats biting each other, and it causes a disease similar to AIDS. Some cats can go for years without showing symptoms after the initial infection, and the lifespans of FIV-infected cats seem to be similar to uninfected cats. 

6. Diabetes

A cat at risk for diabetes. Image Credit: Tripp via Wikimedia Commons // CC BY 2.0

Dogs and cats can become diabetic, and much like in their owners, pet diabetes rates are on the rise. The disease is more common in female dogs and male cats, and typically occurs in overweight, middle-aged animals. A 2012 survey estimated that more than half of dogs and cats are overweight or obese, putting them at risk for type 2 diabetes. Monkeys, too, can get diabetes from eating too much sugar, including from bananas

But not all animal diabetes is problematic. In 2010, researchers found that bottlenose dolphins have a condition that’s not unlike type 2 diabetes in humans—but they can turn it on and off, a feature scientists are studying in hopes that it will lead to better treatment for diabetic humans. 

7. Arthritis 

Elderly pets often fall prey to chronic arthritis, the swelling of joints. To give them some relief, some pet owners are turning to acupuncture for dogs and cats. Small animal acupuncture programs even cover acupuncture for birds.

8. Cavities 

Up to 60 percent of cats are affected by tooth resorption (sometimes called “cat cavities”) which erodes the tissue inside the tooth. Cavities are more common in cats, but can occur in dogs as well. 

9. Influenza

Some of the biggest flu scares of the last few years have come from animals, like avian flu and swine flu, and birds and pigs aren’t the only animals who can get it. Bats can get it too, although so far it seems bat flu can’t infect humans. Other animals have more to worry about from us than we do from them. Pets can get the flu from their owners, and may get it more often than you’d think. One study of cat blood samples in Ohio found that 30 percent of cats had been infected with the seasonal flu. 

10. Urinary Tract Infections

One of humanity’s most common infectious diseases also plagues much of the mammalian population. UTIs can infect koalas, horses, and rabbits, causing them to pee more often, and painfully. Dogs are more likely to get UTIs than cats, who rarely get them before the age of 10. 

11. Tuberculosis 

Image Credit: Peter Trimming via Flickr // CC BY 2.0

Badgers and cows can get TB, and potentially spread it to humans. The first reported case of a person infected with the agent that causes tuberculosis in cattle dates back to 1902. And bovine TB is on the rise, putting humans at risk for contracting the disease through contaminated milk. In 2012, English cow farmers tried to institute a badger cull to stop the furry little predators from infecting their herds. The controversial measure was piloted in several regions of England in 2013. 

12. African Sleeping Sickness 

Sleeping sickness is transmitted by tsetse flies, which live in sub-Saharan Africa. Cattle and other livestock can be infected. Nagana, as the animal version of the disease is called, reduces fertility and milk production in cattle (not to mention its impact on mortality rates), and the World Health Organization calls it a major obstacle to economic development in affected areas. 

Watch How a Bioluminescence Expert Catches a Giant Squid

Giant squid have been the object of fascination for millennia; they may have even provided the origin for the legendary Nordic sea monsters known as the Kraken. But no one had captured them in their natural environment on video until 2012, when marine biologist and bioluminescence expert Edith Widder snagged the first-ever images off Japan's Ogasawara Islands [PDF]. Widder figured out that previous dives—which tended to bring down a ton of gear and bright lights—were scaring all the creatures away. (Slate compares it to "the equivalent of coming into a darkened theater and shining a spotlight at the audience.")

In this clip from BBC Earth Unplugged, Widder explains how the innovative camera-and-lure combo she devised, known as the Eye-in-the-Sea, finally accomplished the job by using red lights (which most deep-sea creatures can't see) and an electronic jellyfish (called the e-jelly) with a flashy light show just right to lure in predators like Architeuthis dux. "I've tried a bunch of different things over the years to try to be able to talk to the animals," Widder says in the video, "and with the e-jelly, I feel like I'm finally making some progress."

[h/t The Kid Should See This]

Big Questions
Why Are There No Snakes in Ireland?

Legend tells of St. Patrick using the power of his faith to drive all of Ireland’s snakes into the sea. It’s an impressive image, but there’s no way it could have happened.

There never were any snakes in Ireland, partly for the same reason that there are no snakes in Hawaii, Iceland, New Zealand, Greenland, or Antarctica: the Emerald Isle is, well, an island.

Eightofnine via Wikimedia Commons // Public Domain

Once upon a time, Ireland was connected to a larger landmass. But that time was an ice age that kept the land far too chilly for cold-blooded reptiles. As the ice age ended around 10,000 years ago, glaciers melted, pouring even more cold water into the now-impassable expanse between Ireland and its neighbors.

Other animals, like wild boars, lynx, and brown bears, managed to make it across—as did a single reptile: the common lizard. Snakes, however, missed their chance.

The country’s serpent-free reputation has, somewhat perversely, turned snake ownership into a status symbol. There have been numerous reports of large pet snakes escaping or being released. As of yet, no species has managed to take hold in the wild—a small miracle in itself.

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