Archives for September 2012

A Crossdressing Bunny’s Ears and Being Way Too Dedicated to Your Job

Most dog and cat owners who have pets that shake their heads or paw at their ears think first of mites. Ear mites are like disgusting tiny crabs which live in the ear. They can cause intense itchiness and pawing at the head. Ear mites are more common in kittens and stray dogs and cats, since you have to catch them from close contact with another infected animal. Ear mites are NOT common in adult cats and dogs; they typically have allergies or infections (or infections caused by allergies) causing their discomfort.
This is important, because many pet owners will treat their pets ear scratching with over-the-counter ear mite medicine, and then be surprised when it doesn’t work. 
However, bunnies are a different matter, Especially rabbits that have been bought off of Craigslist (more on Craigslist in a future post.)
Dutchess had crusty, scabby painful ears since the owner purchased him. On exam, we first discovered Dutchess had testicles, and should be named Dutch. It may sound funny, but it is fairly common for many owners to find out that their “Petunia” is actually “Pete” the first time they come for an appointment.

Dutch, a little insecure in his masculinity after being mistaken for a girl for almost a year
Dutch’s ears were itchy, and the scabbing was painful. We did get a small sample to examine under the microscope, and it confirmed what we highly suspected. Ear mites in rabbits can become severe, eventually spreading outside the ear across the face. Luckily, they are easily treatable with medication and good cage hygiene.
Ear Yuck
That would make my ears itchy. There is a 1993 Journal of the American Veterinary Medicine Association (JAVMA) , article about a veterinarian who infected himself with cat ear mites. He reported, besides the intense itchiness from the mites biting the insides of his ears, that he could feel the mites crossing over his face from one ear to the other while he slept, and could hear the crunching noise as they scrabbled through his ear canal. He treated himself, and then reinfected himself, several times. Surprisingly, after the first few times he infected himself, the itching started to lessen, and he became a chronic ear mite carrier.

So, besides the fact the ear mites are completely disgusting and vile, we have learned that there are veterinarians who are much much more dedicated to their job than I am. Beyond any self-preservation, I am married, and while my wife is very nice, she does have her limits. I would prefer to stay married; do not expect me to add to the human self-inflicted-ear-mite research.
If you still need to be grossed out further, here is a case of inadvertent human ear mite infection.

Update on Max

We have had some issues with his surgery. Excessive movement, as well as the Collie’s inherently obsessive behavior, has led to the incision site opening up. We had to add some strength holding sutures, which are placed further out from the incision to help hold it together. We augmented these stitches with small pieces of tubing to help keep them in place.
We also had to add a drain, which is a length of flexible flaccid plastic tubing which allows built up fluids to escape.
Lastly, he’s been condemned to the dreaded “cone of shame,” which I always hate using. Dogs do hate them, for multiple reasons. Besides making it difficult to get around, it also makes everything incredibly loud. Try putting one on yourself- it’s an excellent amplifier.
Most importantly, and unfortunately, Max’s histopathology results showed that some cancer remains, even after such a dramatic surgery. He will be consulting with a veterinary oncologist in the next few weeks to discuss other treatments.

Cat Teeth: Not All Holes Are Not Cavities

Sasha the beautiful fluffy Himalayan cat had been hiding under the bed more than normal, and when she was out she could sometimes be found sitting, staring at the wall. She had been eating fine, so it couldn’t be a problem with her mouth… or could it?
Cats only have 30 teeth compared to a person’s 32 (and a dog’s 42!), but the species’ differences do not end there. A cat’s teeth are designed more for puncturing, slicing, and tearing, rather than the chewing that we humans do. While cats and people both get cavities, they are usually in totally different ways, and with completely different results.
Image via www.catster.com.
Cats, dogs and humans all develop tartar and plaque on their teeth over time. Brushing the teeth, eating properly and routine dental care helps to slow this process. In people, bacteria in this tartar and plaque can eat away at the tooth wall, eventually leading to a cavity, or hole in the tooth. While cats develop tartar, their “cavities” are typically not related to tartar and bacteria, but rather spontaneously occur. These “cavities” are more accurately called Feline Odontoclastic Resorptive Lesions, or FORLs, and are surprisingly common. They usually appear on the tooth at the gum line, and can erode the tooth enamel until the nerve root is exposed, which can cause severe pain. FORLs left untreated eventually eat away at so much of the structure of the tooth that the tooth spontaneously shatters. This process can cause discomfort for months or years.
FORL in lower third premolar- it’s a dramatic hole in the tooth!
While we know that tartar and plaque alone are not the cause of FORLs, we do not know what does cause these cat cavities. Some have theorized it is related to cat food, although skeletons of our pet cat’s ancient ancestors show evidence of FORLs thousands of years ago, long before cat food was developed. There does seem to be a genetic component, since FORLs are more common in certain purebred breeds, such as Siamese and Himalayans. 
Unlike human cavities, FORLs typically do not respond well to fillings or even root canals. Usually, the affected teeth have to be extracted. While this may seem as though it would be uncomfortable, these teeth are so painful that removing the tooth is a huge relief. While FORLs are common, they are not the only dental problem a cat can have, so a proper diagnosis is vital; dental x-rays may be needed to fully analyze the tooth roots.
Gum tissue is trying to fill in the FORL in the cat canine (the fang)
Thanks to the American Veterinary Dental Society
Many astute owners miss that their cat has FORLs. Even the best pet owners have difficulty looking at the rear teeth, and this is even more true if the mouth is uncomfortable. Sometimes, tartar or a swollen gum may obscure the FORLs. While difficulty eating would seem to be an obvious sign, many cats with painful teeth simply choose to chew on the other side of their mouth, or not chew much at all. Since a cat’s teeth are designed to tear rather than chew, many cats swallow small pieces of food whole, so a difficulty chewing may go completely unnoticed. Often cat owners report that cats with FORLs seem more reserved and quiet, drool slightly, or only vomit more often (since they are swallowing their food whole). They may hide more often, or stare at a blank wall; these can be signs of discomfort in a cat, and should not be ignored. 
Cat FORLs can be very frustrating; with no known cause, and no real treatment except tooth removal, the options can be very limited. Hopefully, continued research in cat dentistry will reveal a way to prevent, or at least treat, this painful cat disease.

Originally published in the Tampa Bay Weekly Newspapers August, 2012

Metastatic Versus Locally Invasive: My Max

When I decided to start this blog, I wanted to use cases I have seen at the hospital to help illustrate some interesting or  important facts about pets. Unfortunately, one of the first examples will be my own dog, Max. It’s unfortunate because of the nature of his disease;
Max has cancer.
Max is such a good dog, and our family is scared. The possibility of losing anyone you love is always gut wrenching, no matter how many legs they have. I am hesitant to use him as an example, because it’s impossible to be objective about your own dog. I’ll try nonetheless.

Max

Max has a soft tissue sarcoma near his right shoulder. We admittedly caught it later than we should have, because originally it was hidden beneath a lipoma, which is a benign fatty tumor.  Sarcomas are malignant cancers, but they spread in a different way than what most of us think when we think of cancer.
Typically, when we think of a cancer in any individual, we think of a metastatic cancer. Metastatic cancers “jump around” the body by traveling through the bloodstream or lymph system. Similar to a dandelion flower, pieces of the cancer go sailing off and settle elsewhere in the body. These pieces can settle in lymph nodes, the lungs, the liver or anywhere depending on the type of cancer. Like dandelion seeds growing new plants, these metastases form new cancers where they settle.

Sarcomas tend to be locally invasive rather than metastatic. Instead of spreading like a dandelion flower, locally invasive cancers spread by sending out microscopic “tentacles” in all directions. It’s like a plant that could completely regrow from the tiniest piece of root. If you are trying to dig up such a plant, you would have to dig a huge hole around the stem, trying to get all the possible roots that you can not see beneath the surface. If you surgically try to remove a sarcoma, you need big margins around the outside if you want to have a chance of completely removing it.


The first time we tried to remove the tumor, two small invisible pieces were left behind and started growing again. His latest surgery was an attempt to remove it for good. His incision is about 11 inches long, with a second cut radiating out from the first. I had to cut out large pieces of muscle and skin, which is why the incision is oddly shaped. It was not a comfortable procedure, but he is on good pain medications and is recovering well; He is walking and eating well, just 48 hours after surgery.

Now comes the waiting part. We sent the tissue to a pathologist, and should hear back whether the “margins are clean” (free of cancer tissue.) With sarcomas, even with a good pathologist report, we will have to monitor the area carefully. The smallest piece can lead to a recurrence.
Are there other treatments besides surgery? Chemotherapy is usually not as effective for sarcomas as other types of cancer. Radiation therapy at a referral hospital does help, and my wife and I have been discussing that option as well.
Hopefully I will report back with good news soon.

Michael Rumore, DVM and Max’s dad

Not a Black and White Movie: What Our Pets See

Whenever movies portray the perspective of a dog or cat, they always use camera at knee level, looking up in black and white. In real life, a pet’s perspective is much different. These differences can be enlightening, and can give us a little glimpse into our four legged friends’ world.
Dogs can see basically two colors, a blue-violet and a yellow-green, with the other colors appearing as gray. Dogs also have a limited ability to differentiate the brightness of colors, with about half the ability that people have. This means for many dogs, different colors appear completely the same; a pattern on the wrapping paper of a birthday present could be literally invisible to them. Cats, who can see shades of gray better than dogs, can also see blue and yellow. While colors may not be obvious, a cat’s ability to detect differences in brightness levels may allow them to see the difference between colors that a dog may miss. 

Dani and I examine a kitty

Both dogs and cats have the ability to see in low levels of light much better than humans. This ability is partially related to the reflective surface in the rear of their eyes called the tapetum. People, who do not have a reflective tapetum, get “red eye” in a camera flash because the blood vessels in the back of the eye are visible. Dog’s and cat’s retinas are covered with a reflective surface, which often appears green, yellow or blue in a camera flash. This reflective surface allows the eye to acquire more light when in dim or dark areas. Additionally, dog’s and cat’s retinas have more rods, which detect dim light, then cones, which detect color. These changes allow dogs and cats to see five to seven times better in the dark than a person.

Nanu and Suszu demonstrate reflective tapetums and humping 
Gabby has a yellow tapetum
Eme and Nyah

The most interesting difference between pets and their owners is in the “processing center” of vision. While we think of our own eyes as simply recording whatever is in front of us exactly as it is, our eyes and brain add many small changes to make it easier for us to see important things, such as edges. This is how some optical illusions work, such as when a printed pattern appears to move as you stare at it; the “edge seeking” processors in our eye get confused by the pattern. This “edge seeking” allows us to be able read, since we can easily differentiate between letters.

“Processing Center” of the Human Eye

Dogs and cats visual “processing centers” don’t have the ability to find edges like ours do, which is why a dog or cat, no matter how intelligent, will likely never read. Their processors are tuned to finding movement, especially horizontally. This is why your pet may stare out the window, intense on watching something, when from our perspective there is nothing there. While our vision may see the detail and edges better, theirs is designed to detect that scurrying mouse or bug.
Dogs and cats truly live in a different world than us. They can see in the dark, and see movement that could be invisible to us. On the other hand, do not be offended is Fluffy seems less than excited about his wrapped birthday present; he may not even “see” the paper at all.

Michael Rumore, DVM

(Originally published in the Tampa Bay Weekly Newspapers in March, 2012)

Here we go…..

Welcome to the inaugural post of the PetAnswers Blog! I have always loved pets, and decided in the fourth grade to become a veterinarian so I could care for my animal friends. It was a good decision; decades later I still find pets and all animals fascinating, and they still bring me great joy both personally and professionally. Follow me a little deeper into the world of our pets- it should be fun, interesting, and you may learn a useful a thing or two as well.

Michael Rumore, DVM