Humans spend billions of dollars every year just on their appearance. As a species, we tend to be far more concerned with how we look than do other species. When it comes to nails, animals, on the other hand, are more interested in how their nails work for them rather than how they look.

Fingernails and toenails of all creatures’ great or small have many similarities as well as differences. To find out what they are, NAILS sent two intrepid reporters to the San Diego Zoo in San Diego, Calif., where they spent a day ‘behind the scenes” discussing the nail care of various animals

THE BIRDS, NOT THE BEES

According to the San Diego Zoo, it has the largest collection of birds in the Western Hemisphere. In a captive environment, nail care is crucial; the toenails are the first to suffer if the perching materials aren’t adequate. Some zoos use PVC or metal pipe perches that can distort nail growth and off-center the nails. The San Diego Zoo offers their birds a variety of perches that come close to those they would use in the wild. Though some nail problems can be related to diet r caused by age, the majority of problems are due to improve perching.

At the San Diego Zoo, toenails are trimmed on an as-needed basis. For small and medium-sized birds, caretakers use a diamond-edge emery board and a nail clipper. They use a dog nail clipper or a Dremel drill for larger birds.

Says Wayne Schulenberg, animal care manager of birds, “At one time we received an Asian hornbill who was in quarantine for 120 days and didn’t receive proper nail care while there. As a result, one of his nails wrapped around and grew into his foot. We removed the nail from the foot, cleaned, packed and bandaged it, and now the bird is fine.”

The zoo’s birds of prey usually grow elongated toenails that need to be filed down, so they go to the hospital about every three months for a pedicure. The biggest bird (weighing 350 pounds) that may require nail care is the ostrich. In Schulenberg’s 21 years here, he has yet to trim an ostrich’s toenails. The smallest bird who may have overgrown toenails is a round-tailed manikin, who weighs in at 5 grams. Left unchecked, its nails can grow and spiraled.

“We’ve had to do nail care on emus, who are highly stressed animals,” says Schulenberg. “One tore a cuticle by kicking a perimeter wall of fence. To treat this, we applied Nexaband, a non-toxic animal super glue on top of wound to hold it together.”

The most dangerous bird at zoo is the cassowary, found in Papa New Guinea and Northern Australia. They are very solitary animals and have three forward toes. The inside toenails has a 6-9-inch stiletto nails that is use for self-defense. New Guineas often try to capture this bird because having one is a sign of wealth. According to Schulenberg, more people have died in New Guinea from being attacked by this bird than from any tropical disease including malaria.

Leapin’ Lizards

At the San Diego Zoo, the nail care for iguanas and lizards is on as-needed basis since reptiles in captivity don’t have enough rough surfaces to grind their nails down. However, arboreal (three-dwelling) species, such as the Fijian banded iguana, don’t require nail trims because they need long nails for climbing.

In the wild, reptiles, such as the Gila monster, use their sharp nails for digging – to get out of the heat, to hibernate or hide, to find bird eggs or reptile eggs, or to bury their own eggs. In captivity, these animals need a little extra attention paid to their nails. Caretakers use a nail clipper, which looks identical to a nail technician’s tip cutter, to trim the nails of reptiles, who are easily strained for the trimming.

Hay Is For Horse

Hoofed animals, called ungulates, have foot structures that are more complex than those of birds and reptiles. Therefore, they require more detailed nail care in captivity because without regular maintenance they can develop a number of serious conditions.

All hoofed animals at the zoo get their hooves trimmed about twice a year. All the exotic ones, such as the zebra, Przewalski’s horse, and the white-lipped deer, need to be sedated for hoof care.

One of the zoo’s equines, Sugarplum, a 13-year-old miniature horse, gets her hooves trimmed about every 10 weeks, depending on how much exercise she gets. To do the hoof trim, Tom Sica, lead hospital keeper uses a hoof knife to remove excess growth on the frog (a wedge-shaped cushion of the foot that is unique to equines). The frog helps with circulation. Every time a horse takes a step, the frog pushes blood up the leg to return to the heart. Cleaning the frog is a vital part of the hoof trim because the animal can get bacterial growth under the whole foot, which can lead to thrush, a disorder of the foot.

Next Sica uses a hoof nipper to remove excess growth from the hoof wall. He also uses a hoof rasp with a fine grit on one side and a rough grit on the other in order to get the hoof wall grows out too far, it can break off, causing the edges to split and crack, which can become extremely painful.

Other hoofed animals at the zoo which h don’t normally require nail care but have incidental problems, says Sica, are the red River hog and the black rhinoceros. The hog injured his leg while in quarantine and Sica had to use epoxy to balance out his toe and level it.

The rhinoceros had an abscess between each toe on his front hoof, so Sica had to dig each one and drain it. For really hard feet like the rhino’s, Sica uses a grinder with an abrasive disc to take off excess growth from the hoof wall.

Here, Kitty, Kitty

Big cats have paws with claws identical to a normal house cat, only several times larger. Luckily for the caretakers at the zoo, big cats take care of their own nails by scratching on logs and trees.

Scratching on trees is also a way for cats to mark their territory. For example, one cat may spray the lower part of a tree trunk with urine to mark his territory, and another cat may come along and use his claw to scratch the area above the urine stain as a challenge to their territorial rights of the first cat.

Cats of all sizes use their claws to climb trees, to defend themselves, and to attack. Felines also have a special feature unique to them – retractile claws. In order to use its claws, a cat must flex its muscle. Otherwise, this muscle is at rest and the claws are retracted. Retractable claws also allow cats to quietly sneak up on their prey. When cats age, the retractile muscle loosen with time causing their paws to click when walking on hard surfaces.

The only cat that does not have retractable claws is the cheetah. This swift-moving cat uses it claws as cleats for traction when running.

Cats that don’t groom themselves (nails included) are often ill, says Susan Euing, senior animal keeper of Sun Bear Forest.

Another animal well-known for its “killer” claws is the bear. Bears have five claws on each paw and groom their own nails by chewing on them. This causes the outer layer to split off.

Says Euing, “We had a Malayan sun bear who had split claw, which eventually sloughed off on its own, but left behind some bare skin. We kept the area clean with warm water and treated it with Betadine.

Sun bears and back bears are arboreal, so they need their claws for climbing trees. All bears use their nails for grooming, climbing, feeding, and as weapons.

Though there is no regularly scheduled nail care for the big cats and bears at the zoo, their nails are checked at their annual physical

An Elephant Never Forgets (Its Pedicure)

The leading cause of elephant mortality in captivity is from infections that begin in the foot and their become systematic, says Gary Priest, head of the Department of Animal Behavior Management at the Zoological Society of San Diego. So for elephant keepers, ensuring clean smooth footpads is job number one, he says.

Elephants walk on their tiptoes and use their feet to dig in the dirt and to break branches. Asian elephants have five toenails on their front feet and four toenails on their back feet, whereas African elephants have four toenails in front and three in back.

Asian and African elephants sweat around their cuticles, but Asian elephants require more cuticle care than African elephants because they have more growth area in that area. The cuticle is the most sensitive part of an elephant’s foot. For dry cuticles, the elephant keepers apply lanolin or vitamin E.

Elephants at the zoo receive a pedicure on all four feet about 3-4 times a year. African elephants don’t need a as much nail care because their cuticles don’t wear their footpads down says Dustin Black, elephant keeper. It takes about 1-2 hours to do a pedicure on one foot. Elephants usually require trimming on the inside nails more than the outside nails because of the way they walk.

When doing a pedicure, Black always makes sure to look for small pebbles that can get lodged in the cracks of the footpad. Growth on the footpad is similar to a thickened callus. The dead portion of the footpad can be up to 1/8-inch thick, most of which shaved off with a hoof knife.

One of the zoo’s Asian elephant, Smithy, a 27-year-old female who weighs 8,700 pounds, recently had work done on a crack nail. Says Black, “I had to open up the cracked area with a hoof knife, then file the sides of the crack to smooth it out. This keeps it from snagging on debris and takes the weight off the stressed area. If I didn’t open up the crack area, water could get trapped inside and cause a bacterial infection, similar to thrush in horse.”

Which goes to show that proper hygiene and nail care is just as important for animal hooves, claws, and feet as it is for human fingernails and toenails. In the wild, animals have to do their own nails, but in captive environments, some animals must rely on their caretaker to their nail technician as well.

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