June 2020 • Encyclopaedia Felidae

Abyssinian: Pharaoh’s Treasure

June 28, 2020May 12, 2023 mehshadoweye

Meredith Hemphill

mehshadoweye

Encyclopaedia Felidae now has a Patreon! Go to www.patreon.com/EncyclopaediaFelidae if you want to help support this content!

Two brown Abyssinian cats on kitchen chair — Royalty in the kitchen – Image by Dmitry Tsapenko from Pixabay

Ancient Egyptian art is full of regal cats with lithe, muscular bodies, arched necks, large, wildcat ears, and almond-shaped eyes. It is no surprise that the Abyssinian breed is widely believed to be the descendants of the cats of the ancient Egyptians, held in such high regard thousands of years ago. The resemblance is uncanny. Although it is a myth that Abyssinians are the cats of the Pharaohs, this breed has no problem commanding your attention in its own right.

Abyssinian Imports

The first record of an Abyssinian cat comes from the January 27th, 1872 issue of Harper’s Weekly in a report on the 1871 Crystal Palace Cat Show [1]. A she-cat named either Zulu or Zula took third place. She was described as an Abyssinian, “captured in the late Abyssinian war” [1]. An illustration is provided, which shows a cat with tabby facial markings but the ticked coat typical of Abyssinians [1]. Otherwise, however, Zulu does not look like the Abyssinian as we know it today, having rather small ears and a rounder face [1, 2].

Abyssinia is an old name for Ethiopia. The story goes that a British Captain brought Zulu home from Abyssinia in the 1860s and began to breed her when her unusual ticked coat was so well-received in Britain. Because of her cat show win, we know that Zulu existed, but whether she is the mother of the breed is contested. She may have been to begin with. There is a theory that Zulu was used to begin the breed, but her line died out, and other cats with ticked coats, perhaps the British “Bunny cats” with similar markings, were bred to re-establish the breed [2]. Genetic evidence links Abyssinians to Southeast Asian and Western European cat populations [3]. This had led to the idea that British and Dutch traders may have brought the breed’s progenitors from Indian or Indonesian ports [4].

Breed Characteristics

Appearance

Mother Abyssinian cat with kitten on sofa — Image by Dmitry Tsapenko from Pixabay

The Abyssinian today is notable for the ticked coat that has distinguished it all along. Ticked or agouti fur is related to the tabby pattern (see my article on coat pattern genetics). There are no tabby stripes, only the tabby M on the forehead, but each individual hair is striped with alternating bands of color. Abyssinians have a darker band of fur along their spine and a lighter underside. They are best known in their ruddy (reddish-brown) coloration, but can also be red, blue, or fawn. Their fur is short, dense, and silky. Long-haired Abyssinians do crop up, but they are considered a separate breed, the Somali.

Their patterning reminds some people of a wildcat, an idea reinforced by the Abyssinian’s shape. The breed looks a lot like the ancestor of domestic cats, Felis lybica. They have a muscular body, wedge-shaped head, and large, alert ears that give them a very attentive appearance. The legs are slim and the tail long and tapering. Their almond-shaped eyes are often surrounded by dark lines and may be green or gold. Despite an aspect of wildness, Abyssinian cats are 100% domestic cat. They are not, however, likely to be a lap cat.

Personality

Abyssinians are playful, social, and very athletic. They are known for a love of climbing and a high degree of intelligence that can get them into mischief if they’re bored. They are very loyal to their people and perform all sorts of antics to get their attention. Because they are so energetic, they don’t usually like to be cuddly, but they do like to be around and involved in whatever is going on. They are usually good with other pets and with children. They can get bored and distressed if left alone for long periods of time, so in a house where everyone needs to leave for work and school they will probably need an animal companion and plenty of toys to keep them busy. Puzzle toys are fantastic for challenging their active brains as well as their active bodies.

These cats are fast learners. This makes them great at learning tricks, but it also makes them good at learning how to get into trouble. And they have a knack for training their people to do what they want. Abyssinians are delightful companions, but they do need lots of stimulation and a watchful eye to keep them out of mischief!

Abyssinian antics

Health

As with any breed, there are some health concerns with Abyssinians. Their athletic nature typically fends off obesity and keeps them fit, but there are some inherited disorders in the breed that even their great athleticism cannot counter. Progressive retinal atrophy, an eye disease which causes blindness, is associated with the breed [5]. Abyssinian cats have known risks of developing early periodontal disease; hypertrophic cardiomyopathy; patellar luxation, a hereditary dislocation of the kneecap, which may be surgically corrected; renal amyloidosis, a hereditary disease that leads to kidney failure; and hyperesthesia syndrome, a neurological disorder that causes excessive grooming [4, 6].

Abyssinians are particularly known for having the mutation for pyruvate kinase deficiency in their gene pool. Pyruvate kinase is an enzyme required for the normal functioning of red blood cells [7]. Cats with the deficiency develop intermittent anemia, which may begin anywhere from the age of six months to twelve years [7]. Fortunately, a test is available for the mutation that causes pyruvate kinase deficiency, so the disease can be removed from gene pools [7]. However, there is no definitive treatment for the disease, so even if the breeder says that their bloodline is free of the disorder, it is safest to have your cat tested [7].

Abyssinian cats may not have sunned themselves beside the Nile thousands of years ago, but they are no less regal for having more recent and probably rather mundane origins. As the Egyptians well understood, there is nothing prosaic about a cat. Should you choose to bring an Abyssinian into your family, they will be sure to teach you that themself.

Fun Facts

The first cat genome to be sequenced came from an Abyssinian named Cinnamon [6, 8].
Two Abyssinians named Amber and Rumpler co-starred as Jake, the alien cat in the 1978 film The Cat from Outer Space [9].
In 2019, the Cat Fanciers’ Association ranked Abyssinians their #8 most popular cat. The breed was one of their six founders in 1906 [10].

Works Cited

Macquoid, P. (1872, January 27). An afternoon with the cats. Harper’s Weekly, 89-90.
Abyssinian. (n.d.). Petfinder. https://www.petfinder.com/cat-breeds/abyssinian/
Lipinski, M.J., Froenicke, L., Baysac, K.C., et al. (2008). The ascent of cat breeds: Genetic evaluations of breeds and worldwide random-bred populations. Genomics, 91(1), 12-21. https://doi.org/10.1016/j.ygeno.2007.10.009
Cat Time. (n.d.). Abyssinian. https://cattime.com/cat-breeds/abyssinian-cats
Narfstrōm, K. (1983). Hereditary progressive retinal atrophy in the Abyssinian cat. Journal of Heredity, 74(4), 273-276. https://doi.org/10.1093/oxfordjournals.jhered.a109782
Basepaws. (2019, March 5). Abyssinian – Meet the miniature cougar. https://www.basepaws.com/blog/abyssinian-cat-breed/
Vetstreet. (n.d.). Abyssinian. http://www.vetstreet.com/cats/abyssinian#health
Pontius, J.U., Mullikin, J.C., Smith, D.R., et al. (2007). Initial sequence and comparative analysis of the cat genome. Genome Research, 17, 1675-1689. https://genome.cshlp.org/content/17/11/1675.short
VCA Hospitals (n.d.). Abyssinian. https://vcahospitals.com/know-your-pet/cat-breeds/abyssinian
Cat Fanciers’ Association. (2020, February 9) The Cat Fanciers’ Association announces most popular breeds for 2019. https://cfa.org/cfa-news-releases/top-breeds-2019/

Published June 28th, 2020

Updated July 20, 2022

Cat Care

Feline Heartworm Disease

June 21, 2020May 12, 2023 mehshadoweye

Meredith Hemphill

mehshadoweye

Encyclopaedia Felidae now has a Patreon! Go to www.patreon.com/EncyclopaediaFelidae if you want to help support this content!

To quote Cats the musical, “A cat is not a dog.” This is a fact that is both obvious and often overlooked. Sometimes, cats and dogs are subject to the same illnesses, but that does not mean that they will have the same symptoms or can receive the same treatments. Heartworm disease is a prime example.

Heartworm lifecycle – American Heartworm Society

Heartworm is the common name for a blood-borne parasite, Dirofilaria immitis, which normally resides in the heart or attached large blood vessels of an infected animal (1). Mature female worms are 6-14 inches (15-36 centimetres) long and 1/8 inch (3 millimetres) wide, with mature males about half that size (1). They can infect dogs, cats, ferrets, and even, rarely, humans (2). Wild hosts include wolves, coyotes, foxes, and sea lions (2). The heartworm lifecycle begins when a mosquito bites an infected animal. The mosquito sucks up larvae circulating in the bloodstream, called microfilaria (2). The larvae develop into an infectious stage in the mosquito and then enter a new host animal when the mosquito bites it (2). The larvae migrate to the right side of the new host’s heart, where they will mature into adult worms over the next six months.

Heartworms can only be transmitted by mosquitos, not between individual animals, although having a significant population of infected hosts increases the likelihood of infection. Heartworms can live for 5-7 years in dogs and 2-4 years in cats (3), so the infection burden in an animal population can increase quickly over several mosquito seasons, and individuals can be infected multiple times. Heartworm infection is possible throughout the United States and in many other countries throughout the world. Thirty species of mosquito can carry the larvae (1). Infected wildlife or mosquitoes can travel great distances, and infected pets may be moved or adopted to new areas (1), so it is safest to assume that if there are mosquitoes where you live, there is a risk of heartworm.

Worms in plastic container — Preserved heartworms (I know, gross) – Image by Mirko Sajkov from Pixabay

Cats are not a very good host for heartworms. Canines are more hospitable to the parasites. Cats are infected 5-20% as often as dogs in the United State, depending upon the location (4), and the worms often fail to mature inside their bodies. Cats also are unlikely to have circulating microfilaria, and about a third of infections in cats have mature worms of the same sex and therefore produce no larvae at all (5). However, just because cats are an imperfect host does not mean that they cannot suffer severe or sometimes fatal symptoms.

Because cats are so much smaller than most dogs, they don’t have space for nearly as many of the parasites. They usually have only 1-3 mature worms, if they have any adults at all (2). Even a few worms is still considered a heavy infection, however, due to a cat’s size (3). And even a cat with only immature worms can still have significant disease. Although the term “heartworm disease” would suggest that the symptoms primarily affect the heart, in cats heartworms tend to cause respiratory problems. Heartworms, once mature, often take up residence in the pulmonary arteries that take blood from the heart to the lungs (6). There, worms can block the arteries, and dead and dying worms cause inflammation that compounds the problem (6).

Cats are subject to a complication known as heartworm-associated respiratory disease (HARD). The symptoms of HARD are rapid and labored breathing, coughing, and gagging. Unfortunately, these symptoms are also indicators of asthma or bronchitis, making it difficult to distinguish a heartworm infection from other forms of respiratory distress. Other symptoms of heartworm infection are also non-specific: vomiting, loss of appetite, and weight loss. In more severe cases, cats may have seizures, faint, struggle to walk, or accumulate fluid in their abdomens. Sometimes, the first sign that something is wrong is sudden death.

If heartworm is suspected in a cat, it is much harder to diagnose an infection than in a dog. It is typical to have to use multiple tests, often more than once (7). This is because the unusual nature of heartworm infection in cats makes many tests less reliable, including the antigen blood test which is the gold standard for dogs (7). The antigen test detects mature female worms, but will not detect an infection with only male or only immature worms (5). Because both of those types of infection are likely in cats, there is a high rate of false negative results. Still, 50-70% of cats are estimated to have at least one female worm, so the test is worth a try (7).

The antibody test is another blood test which detects the cat’s immune response to the parasite. While antigen tests can only detect an infection after 6-8 months, once the parasites are mature, the antibody test is effective as early as two months after infection (7). The antibody test can be highly sensitive, but it’s reliability decreases over time and may be affected by the use of certain medications to treat the infection (7). It can also still be positive after a cat has fought off an infection but the antibodies are still in their blood (7). As the antigen and antibody tests are both useful but have major pitfalls for cats, they are best used together.

If the results of the antigen and antibody blood tests are inconclusive, there are other options. The blood can be tested for circulating microfilaria, but less than 20% of cats will have microfilaria, and then only for 1-4 weeks, so the chances of finding them are low (1). X-rays and ultrasounds of the heart and its vessels can look for changes in the shape of the heart and pulmonary arteries (1). Sometimes an ultrasound will even find the mature worms themselves, although this is uncommon since cats have so few worms (1).

When a heartworm infection can be diagnosed, treatment is its own challenge. The medication used to treat heartworm in dogs, melarsomine dihydrochloride, has been shown to be toxic to cats (8, 9). Cats that appear to be doing well or have no symptoms at all may be allowed to continue fighting the infection on their own while being continually monitored and routinely re-tested (7). A course of steroids is a common treatment for cats that need more support.

If a cat is in need of acute care, a veterinarian will step in with treatments for shock and symptoms, such as oxygen, intravenous fluids and steroids, or bronchodilator drugs to open up their airways (7). The goal is to stabilize the cat until they can eliminate the infection on their own. As measures of last resort when an otherwise stable cat seems to have trouble doing this, the drug ivermectin can be given to kill adult worms, or worms may even be surgically removed (7).

Gray and white cat in red window box — Take care of your cat’s heart <3 – Image by Melinda Rózsa from Pixabay

Obviously, heartworm disease in cats is a complicated and difficult matter. The best treatment is prevention. Heartworm preventatives are available as monthly oral or topical medications, or an injection given every six months by your veterinarian (2). In the United States, heartworm medication is available by prescription only, but on the bright side, most heartworm medications also prevent intestinal parasites, and some are effective against external parasites like fleas and ticks (2). The American Heartworm Society recommends using year-round prevention even in places with cold winters, just in case (2). Indoor cats should be treated as well. Mosquitoes have a knack for making their way inside. About a third of cats with heartworm infections are indoor-only (1). You can’t underestimate the diabolical sneakiness of mosquitoes.

For more information about heartworms, visit the American Heartworm Society at https://www.heartwormsociety.org/ or any of the resources below.

Works Cited

Barnette, C. and Ward, E. (n.d.). Heartworm disease in cats. VCA Animal Hospitals. https://vcahospitals.com/know-your-pet/heartworm-disease-in-cats
American Heartworm Society. (n.d.). Heartworm in cats. https://www.heartwormsociety.org/heartworms-in-cats
U.S. Food and Drug Administration. (2019, August 22). Keep the worms out of your pet’s heart! The facts about heartworm disease. link here
Ryan, W.G., et al. (1995). Prevalence of feline heartworm disease – a global review. American Heartworm Society. Proceedings of the heartworm symposium 1995, 79-86. https://www.cabdirect.org/cabdirect/abstract/19960805975
Stannard, R. (n.d.). The facts about feline heartworm disease. Today’s Veterinary Practice. https://todaysveterinarypractice.com/the-facts-about-feline-heartworm-disease/
Cornell Feline Health Center. (n.d.). Heartworm in cats. Cornell University College of Veterinary Medicine. link here
Jones, S., et al. (2014, October). Current feline guidelines for the prevention, diagnosis, and management of heartworm (Dirofilaria immitis) infection in cats. American Heartworm Society. PDF
McLeroy, L.W. (1998). Evaluation of melarsomine dihydrochloride for adulticidal activity against Dirofilaria immitis in cats with intravenously transplanted adult heartworms. MS Thesis, 95. University of Georgia, Athens, GA.
Goodman, D.A. (1996). Evaluation of a single dose of melarsomine dihydrochloride for adulticidal activity against Dirofilaria immitis in cats. MS Thesis, 95. University of Georgia, Athens, GA.

Published June 21st, 2020

Updated November 4th, 2020

Culture, Science

Hemingway’s Cats and Feline Polydactyly

June 6, 2020May 12, 2023 mehshadoweye

Meredith Hemphill

mehshadoweye

Encyclopaedia Felidae now has a Patreon! Go to www.patreon.com/EncyclopaediaFelidae if you want to help support this content!

“One cat just leads to another.” –Ernest Hemingway

If you visit the Hemingway House in Key West, Florida, USA, you will find that there is something special about the historic home: it is crawling with cats. This is no feral cat colony run amok. The cats here are friendly and well-cared for, happy to be petted or to sit in the laps of guests (1). But if you do get up close with one of these cats, you may notice something special about them, too. About half of the cats at the Hemingway House have extra toes (1)!

White two-story house with trees — The Hemingway House – Image by Michelle Maria from Pixabay

Polydactyly is Greek for “many fingers.” It is a genetic condition that causes extra digits. The trait has been found in humans, mice, dogs, cats, horses, cattle, goats, sheep, springboks and birds (2). Polydactyly is seen more often in cats than any other mammal, although no one knows exactly why (3). Sailors used to consider cats with extra toes even luckier to have aboard than a normal cat. It was thought that they were better mousers and could keep their balance better on rough seas (4). It’s suspected that sailors and their lucky ship’s cats are the reason that polydactyl cats are particularly common along the northeast coast of North America (4), and the same may explain their prevalence in Key West.

According to legend, a nautical friend of Ernest Hemingway gifted him a white, six-toed cat variously named Snow White, Snowball, or Princess, depending upon who you ask. Snowball then snowballed into up to eighty cats living at his Key West home, many of which inherited her extra toes. Today, many cats around Key West, not just at the Hemingway House, are polydactyl.

The truth of this tale is uncertain. While Hemingway certainly had a fondness for cats, some friends and family members say there was no Snow White/Snowball/Princess, or that he never kept cats in Key West at all. Whatever the truth may be, when the Hemingway House was turned into a museum in 1964, it abounded with cats. The family who kept up the museum chose to care for the cats as well, however they might have come to be there. Hemingway named many of his cats after famous people, and this tradition is kept up with Hemingway’s cats today (1).

Orange and white polydactylcat on pile of shirts — Archie Andrews has taken over the gift shop. Count the toes carefully. He has an extra on each front paw! – Photo by Hemingway Home Museum

In honor of the legendary connection between Hemingway and the lucky six-toed cats, polydactyl cats are often called Hemingway cats no matter where they live. The average cat has five toes on each front paw (including the dew claw) and four toes on each hind paw, for a total of eighteen. Polydactyl cats can have a wide variety of numbers and positions of extra toes. The extras are usually on the front paws or on both the front and back, but rarely on only the hind paws. Two of the most common configurations are called “mitten paw” and “patty paw” (2).

“Mitten paws” have extra toes to the side of the normal toes, causing the cat to look like they have mittens on (4). “Patty paws” have extra toes in line with the other toes, resulting in paws that just appear rather large (2). However, other configurations are possible. Polydactyly is a complex trait. It is caused by a dominant mutation that affects limb development very early on, hence the wide array of possible presentations (3).

Occasionally, polydactyl cats can have health problems such as nail infections, ingrown claws, or bone abnormalities (3, 4). In the vast majority of cases, however, the cats have no difficulty at all. It’s thought that in some environments, polydactyly may even be beneficial. Although the old idea that cats with extra toes are better hunters is generally regarded as myth, it was observed long ago that Maine Coon cats, which evolved as a breed in the wild in New England, had a high incidence of polydactyly. Up to 40% of Maine Coons had extra toes before breeders began to select the trait out (4). It is believed that the extra toes helped give Maine Coons even larger paws than they already have, big paws they use like snowshoes to prevent sinking in deep snow during harsh New England winters (4).

Brown, polydactyl tabby cat in flower bed — An example of “mitten paws” – Photo by Georgy Trofimov on Unsplash

There’s no need for snowshoes in Florida, but the cats at the Hemingway House aren’t required to hunt for themselves, anyway. They are fed, pampered, and seen by a vet once a week. Most are spayed and neutered, with a few left intact to keep the colony at about forty to fifty cats. Although guests are not allowed to sit on the antique furniture, the cats get a pass, because this is their house. I have paid the Hemingway House a visit myself and can vouch for how delightful an experience it is to be surrounded by so many happy cats in a beautiful house. Their unique feet is an added bonus.

If you would like to visit the Hemingway House, the address is 907 Whitehead Street, Key West, FL 33040. They ask that you do not pick up the cats or bring any catnip or catnip toys with you. Apparently this happens a lot and has caused cats to fight over the limited herbal offerings. I imagine the same goes for bringing treats or anything else. No reservations are required, and each ticket includes a 30-minute tour.

Fun Facts

US President Theodore Roosevelt kept a polydactyl First Cat named Slippers while he was in the White House.
The current World Record for most toes on a cat belongs to Jake, a ginger tabby tom with 28 toes (seven on each paw).
There is an unsubstantiated report of a 32-toed cat named Mickey Mouse from 1974 (eight on each paw)!

Works Cited

Hemingway Home Museum: https://www.hemingwayhome.com/cats/.
Hamelin, A., et al. (2016). Clinical characterisation of polydactyly in Maine Coon cats. Journal of Feline Medicine and Surgery, 19(4), 1-12. DOI: 10.1177/1098612X16628920
Basepaws. (2019). Genetics of polydactyly: Celebrating the Hemingway cats. https://www.basepaws.com/blog/genetics-of-polydactyly-celebrating-the-hemingway-cats/.
Manhattan Cat Specialists. (2019). Polydactylism (extra toes). https://www.manhattancats.com/blog/2019/august/polydactylism-extra-toes-/.

Published June 6th, 2020

Updated November 4th, 2020