Whinny, Author at Springhill Equine Veterinary Clinic

West Nile Virus

Feb 11, 2012 | Uncategorized

In line with our continued discussion of basic vaccinations and horse health upkeep, I wanted to complete our discussion of what we consider “core” vaccines. Core vaccines are those that every equine (and equid for that matter!) should receive – they include EWT, Rabies, and West Nile Virus. We will continue our blogs with discussion of diseases whose vaccines are not considered part of a core program. Today, we will close with the newest member of the core group – West Nile Virus.

West Nile Virus (WNV), like EEE and WEE, causes encephalitis (inflammation of the central nervous system) and results in neurological symptoms. Humans and other species can acquire this disease as well. West Nile was not found in the United States prior to its introduction to New York in 1999. Clinical signs usually progress back-to-front, meaning the hind-limbs are often affected first, then the forelimbs and so on forward. Early symptoms include inappetance, fever, hind-limb weakness and ataxia. Often the muscles of the muzzle twitch erratically, and they become hyper-excitable. Many horses with West Nile Virus are seen in a dog-sitting position early in the course of the disease, and it progresses to recumbency (lying down) and death. Other neurological signs seen with WNV include blindness, difficulty swallowing, head pressing, seizures, and aimless wandering.

Like EEE, birds keep the source of West Nile Virus alive in the United States, and mosquitoes feeding on the infected birds are the vectors that transmit it to the horse. There is no specific treatment for West Nile, other than supportive care for vital body functions. Recumbent horses must be supported in a sling or turned over every four hours until recovery occurs (if it does). Like with other neurological diseases, when the horse becomes recumbent, euthanasia is generally recommended. Vaccination is recommended once yearly, but it is not a guarantee against infection. The goal of vaccination is to reduce the likelihood of infection, and minimize the clinical signs should infection occur. It is also crucial that you do your part in minimizing mosquito exposure for you and your horse!

You can minimize mosquito populations on your property by eliminating sources of stagnant water (or stocking them with fish), and cleaning out your clogged gutters! Mosquitoes breed in any puddle that is left for more than four days. Keep your barn lights out at night – mosquitoes are attracted by yellow incandescent bulbs. Placing these bulbs at sites away from your barn can draw them away from your horses. Report any dead birds you find on your property to the Alachua County Health Department (DO NOT pick up a carcass without gloves!), and eliminate roosting areas in your barn.

As you are probably wondering, my foot is doing well – the atrophied muscles are starting to come back and my limp is almost gone! I can’t tell you how wonderful it is to be prowling around the office again, inspecting your trailers and your horses. And it was fortunate my recovery happened at such an opportune moment – there’s a new stray lurking around the office that I must defend against! Have a Happy Valentine’s Day, and we hope you can make it to our Senior Horse Seminar this Thursday at 6PM at Canterbury! May your litter box be clean and your food bowl full!

Equine Dentistry. A cat’s eye view.

Feb 4, 2012 | Ailments, Feed

So this week Danielle, one of our technicians, brought her horses into the clinic for their annual dentals. She sat down and told me afterwards all about how Dr. Lacher let her practice using the power tools on her own horses’ teeth and my was it fascinating! Danielle reports that even though she was nervous about practicing, she felt safe that she was in an equine clinic with access to state of the art equipment and facilities and most importantly, our veterinarian’s expertise!

Danielle brought her horses into the clinic early that morning and kept them in a paddock until Dr. Lacher and she had a free moment from their appointments. Once they were ready, they led her first horse “Bumper” into the shade of the barn and then inside the stocks. It was slightly warm that day, so they decided to turn on the fans not only for themselves but for the horse’s comfort. Dr. Lacher calculated the correct dose of sedation for Bumper, which Danielle explained to me, here at Springhill we use just enough sedation to make horses manageable enough to work on their mouths but not too much to make them sleepy for a long time. While sedated, the horse can also lean on the stocks all they like without moving away from us while we are trying to work inside their mouth, which is different in the field because we can’t carry that luxury with us.

While they were waiting for Bumper to get sleepy, they rinsed her mouth with an antiseptic agent which got rid of loose feed material in her mouth and minimized any bacteria. They also gave Bumper her vaccines and drew blood for a Coggins test while she was unaware.

“That’s one of the nice things about sedating a horse for dentals too,” Erica told Danielle, “we can take opportunities to vaccinate, draw blood, and clean a horse’s sheath and not only are they unaware at the time, they won’t remember anything once they are awake.”

After Bumper was sleepy enough, they placed the dental speculum in her mouth and opened it just wide enough to see in the back of her mouth. Then her head was rested on the head loop hanging from the ceiling, after which Danielle adjusted its height so it was comfortable for her to see in Bumper’s mouth. Even with Bumper’s mouth open it was still mighty dark inside her mouth, so Danielle donned a headlamp and looked around while Erica explained what steps she would take to correct Bumper’s mouth.

Bumper’s mouth didn’t need a lot of correcting because Danielle gets her teeth done every year, which she explained makes Bumper more comfortable and will ultimately prolong her life. After Erica inspected Bumper’s mouth with a mirror and pick she determined there weren’t any cavities or cracks in any of Bumper’s teeth. Then, she had Danielle grab the battery operated Makita and told her to take off the sharp points on the outside of Bumper’s top rows of teeth.

“To hold the tool parallel to her teeth, you need to lift up on the back of the Makita” Erica informed Danielle.

“Wow this is gonna work my shoulders for sure!” Danielle exclaimed.

Danielle told me that it was extremely difficult to keep the skinny tool on the side of her horse’s teeth because Bumper was moving her mouth the whole time and her cheeks kept pushing her tool away.

“That’s why we use a skinny tool for that area of her mouth, it’s hard enough already to get in there. Can you imagine not being able to see where that tool was going?” Erica said.

After this step Danielle was instructed to use the diamond burr power tool to work on the rest of Bumper’s mouth. She explained that it was difficult to keep the tool on her teeth, again because Bumper was moving her mouth so much.

“This takes some real skill!” she remarked “I don’t know how you and Dr. King make this look so easy!!”

“You have to learn to stabilize” Erica said, “Otherwise you’ll get pushed off her tooth every time.”

At this point Danielle’s arms were tired, “I feel like I’m not doing a very good job at getting all the way to the back of her mouth cause it’s so hard to see!”

Dr. Lacher then took over and polished up Bumper’s mouth. After making some corrections, Erica changed out power tools again to a smaller one with another diamond burr.

“We use that tool,” Danielle said “to place a bit seat in a horse’s mouth so pulling on the bit doesn’t pinch their gums. We also use that tool to make corrections to a horse’s incisors or front teeth.”

After releasing the speculum from Bumper’s mouth they checked to make sure her incisors were straight and then checked lateral excursion. Dr. Lacher uses lateral excursion to make sure the molars are working just right. Since all looked good, they rinsed her mouth once more to drain the tooth dust out and then waited a few minutes to lead her out of the stocks and back to the shade of her paddock while they grabbed her other horse to repeat the same process.

After all was done I had a new respect for our veterinarians doing dentals. Being able to see in a horse’s mouth makes all the difference for knowing the job was done right and using the power tools is faster and more accurate for sure. I feel confident my horse’s teeth are being done properly because my vets have all the tools they need to thoroughly examine their teeth and prevent small problems from becoming big ones.

Wow, now I’m wondering if I need to go to Newberry Animal Hospital for a kitty dental!

May your food bowl always be full and your litter box clean!

So what’s with that EWT vaccine?

Jan 28, 2012 | Ailments, Leg issues

SO I know everyone is dying to know, so I have to announce to the world that MY CAST IS FINALLY OFF!! I am feeling free and happy, and can go outside again!! I’m still limping a little bit, but since I really haven’t stopped my usual routine of jumping on my front counter, I don’t see that slowing me down now. Thanks to everyone again for all of your sweet rubs, pets and encouraging words that got me through this miserable period of my life!! Next time bring more tuna, words don’t fill my stomach.

OK – so we’re supposed to be talking about this so-called EWT vaccine that you have to give your horse twice a year. Let’s start with the basics – the E represents Eastern Equine Encephalitis (also known as EEE). The W represents Western Equine Encephalitis (WEE), and the T represents Tetanus, which was discussed in our last blog. There is another in the EE group, Venezuelan Encephalitis (VEE), which has not been reported in the U.S. since 1971, and is not routinely vaccinated against in this country. So what is with EEE and WEE, and why do I have to give my horse a vaccine for this twice a year??

Both EEE and WEE are viral diseases causing severe neurological disease, and are carried from horse to horse by mosquito’s. As with West Nile virus, birds are crucial to maintaining the cycle of virus activity from year to year. While EEE occurs more frequently in the eastern U.S., and WEE is generally associated with the western part of the country, each has occurred in Florida. Administration of the vaccine two to three times a year here in Florida is directly a function of our never-ending mosquito season. In the northern parts of the country, EWT vaccination is generally performed once yearly in the spring, as hard freezes cause a break in the disease season. The vaccine appears to be effective at preventing disease for 4 to 6 months, so it is crucial to keep up with this schedule. The vaccine product is killed virus, meaning it has no ability to cause disease, and reactions are rare. Mortality associated with EEE is 75% to 95%, so it is a disease certainly worth preventing.

Horses affected by EEE initially show signs of fever and depression, and symptoms transition into neurological disease about 5 days after infection. The horse often dies 2-3 days after neurological signs set in. The first sign is often a change in behavior, which can be in either direction. Normally calm horses can become irritable and easily excited, attacking owners or themselves. Others may seem “sleepy,” or even ‘forget’ how to lead, in any case, the horse usually refuses feed and water. As the dementia progresses, the horse may compulsively walk in circles, press its head against things, grind his teeth, and develop blindness. Unsteadiness or clumsiness will begin to manifest, as can areas of paralysis (face, tongue, etc.). The horse will eventually go down, which more often than not signifies the end of the battle – a down horse with this disease has a grave outlook. WEE manifests similarly, although generally more slowly and less severely (mortality ranges from about 20 to 50%). It is important to remember that a horse with signs of encephalitis (brain inflammation) is not himself – so be extremely careful around these horses, and stay out of the stall until the vet arrives!

Horses are considered “dead end hosts” of the EE’s – meaning a horse with this disease is of no risk to infect other horses, mosquito’s or birds. Diagnosis involves a CSF tap, so a diagnosis may be presumed if vaccination was >4 months prior, and it occurs in an area where this disease is prevalent (like Florida). Treatment of this disease is supportive, and often ineffective (especially with EEE). It is aimed at symptomatically reducing the inflammation in the central nervous system – there is no cure. Euthanasia is recommended with horses that are down and unable to stand. Horses that do manage to recover often have lasting signs of brain damage. The staff at Springhill Equine firmly believe that every horse deserves at least twice a year EWT vaccination to prevent the devastating effects of these diseases! Check on your horse’s vaccination status, and schedule with us today if you are overdue! May your litter box be clean, and your food bowl full!

Clostridium – Botulism and tetanus and gangrene, oh my!!

Jan 14, 2012 | Uncategorized

After last week’s discussion on Rabies, I decided it was important to discuss another readily-controlled, animal-killing pathogen – Clostridium. This genus, or group of bacteria has more species members than any other genus of bacteria. A book could be, and probably has been, written about all of the Clostridial diseases that exist. Clostridium bacteria produce neurotoxins or tissue toxins when seeded into wounds or ingested. They generally favor environments that are anaerobic (without oxygen). A few of the more notable diseases featured in this group include tetanus, botulism (limber-neck in poultry), gas gangrene, and overeating disease. Others less commonly known include blackleg, red water, Tyzzer’s and black disease. Many people (and foals, lambs, etc.) have been infected with, and killed by C. difficile diarrhea. Any diarrhea, abscess (foot or otherwise), or hot, painful deep tissue infection in a vertebrate could well have a Clostridial source.

Many species in this genus live in the environment all around us, like Clostridium tetani, the organism that causes tetanus (not just on rusty nails!). Some areas of the country (notably Kentucky and Texas), have high levels of botulism in the soil and are avoided. Only a few years ago, C. botulinum bacteria growing in a batch of haylage produced a neurotoxin that, on ingestion, killed over 100 horses in the Ocala area. Botulism is an important disease of foals in the Kentucky area, and vaccination is recommended for broodmares and foals in that area of the country. As it causes flaccid (limp) paralysis, intensive care is required to support almost every bodily function during the weeks of recovery – eating, drinking, and breathing.

Tetanus, like botulism, can kill just about anything. While botulism is usually ingested or inhaled, tetanus is usually associated with a wound, often a puncture wound that is allowed to heal over, creating the perfect warm, airless environment for it to multiple and produce toxins. Its neurotoxin has the exact opposite effect than botulism: the uncontrolled paralysis is “tonic-clonic,” meaning the muscles undergo spasmodic continuous contraction. Stiffness will first be noticed in the limb or area near the wound, and will become generalized in a matter of days. The powerful clamping of the chewing muscles, often resulting in the subsequent starvation, dehydration and death of an animal affected by tetanus, is what gives rise to the term “lockjaw.” The body takes a rigid, arched position as the back muscles contract, overwhelming the abdominal muscles and pulling the head back. There are no blood tests to diagnose tetanus, but often the characteristic symptoms readily point to this historic culprit.

Control of tetanus is easily achieved through annual vaccination. A tetanus toxoid vaccine, given annually, is usually used for small ruminants, but can be given off-label to other species such as al pacas and llamas. Most horses receive their tetanus toxoid vaccine in the “EWT” (Eastern Encephalitis, Western Encephalitis, and Tetanus) combination product twice a year. Ruminants (cattle, sheep, and goats) are usually are given a “seven way” vaccine as youngsters, then annually and pre-breeding that includes overeating disease (C. perfringens). Generally vaccination is recommended starting at 4-6 months of age. The vaccines are inactive bacterial products, so unlike some vaccines, there is no risk of infection from vaccination. It is not uncommon for animals (and people) to be stiff for a day or two after vaccination.

If your animal receives a deep wound, call us immediately! Antitoxin must be given to animals that are not vaccinated if they receive a deep puncture wound that will predispose to infection. This antitoxin has been associated with reactions resulting in liver disease in horses, so regular vaccination is strongly recommended. Like for Rabies, vaccination is cheap, easy and effective! Don’t overlook this important and easily preventable disease when taking care of your horses and livestock.

In the meantime, my spoon splint is finally off!!! …although I still have an annoying bandage on my foot (which I continue to shake at people), I feel like my stall-turned-paddock (when I get to go out in the barn aisle-way) rest is close to over! May your food bowl always be full, and your litter box be ever-clean!

Rabies!!!

Jan 8, 2012 | Ailments

I would like to talk about a very serious subject in this week’s blog: Rabies. Dr. Lacher and Dr. King recently heard about a case of Rabies in a pony in North Carolina and asked me to share some information about Rabies and its management in horses. I was all ears since I too have to be vaccinated for this deadly disease.

Rabies is a virus of mammals which affects the nervous system. The virus is transmitted from an infected animal to other animals through bite wounds, typically from a fox, skunk, raccoon or bat. Once the virus enters the animal it seeks out a nerve to bind to and follow to the brain. The virus is on a search and destroy mission until it reaches the brain, only then does it branch out to other tissues like salivary glands.

We were all taught not to approach the dog foaming at the mouth, it might have Rabies. If a raccoon or fox is seen during the day and is acting aggressive most of us would worry about Rabies. What if your horse was mildy colicky, had a slight lameness or was having difficulty urinating? These are all symptoms of Rabies in horses. And there is the biggest problem with equine Rabies cases. Many of us do not recognize it is Rabies until it is too late. The pony in North Carolina had a wound it was itching and wouldn’t leave alone. In this case, as in many other equine cases, lots of people were exposed to this horse before anyone realized it might have Rabies. This means all these people had to go through post exposure vaccination! That would not make for happy neighbors.

Rabies is definitely a case of the best defense is good offense: vaccination. The rabies vaccine is very effective. It cannot be said with 100% certainty but no one Dr. Lacher or Dr. King could find knows of a single case of rabies in a vaccinated animal. This makes it among the most effective vaccines we have, which is good since we also have no known treatment. It is recommended that horses be vaccinated yearly for rabies. Due to some unique features of the equine immune system it does not respond to the rabies vaccine for very long. Studies have shown that most horses can fight off an exposure for 14-16 months following vaccination making yearly vaccination very important. Humans, dogs and cats do a much better job responding to the vaccine and can remain immune for many years. It is still recommended that dogs and cats be vaccinated at least every 3 years for public health reasons.

You come out to feed in the morning and find a raccoon acting strangely near your horses. What should you do? First, do not try to come near any wild creature acting oddly. Call Animal Control. Move your horses to a safe area as far away from the raccoon as possible. Call Springhill Equine. If your horses are up to date on their rabies vaccines we will administer a second vaccine as soon as possible. If your horse has not been vaccinated a quarantine will be necessary for 6 months! If you suspect your horse may have rabies, call us immediately and limit contact as much as possible. The moral of this story is to vaccinate for rabies. It’s cheap, easy and effective!

On a personal note, my broken foot continues to heal well. Dr. Long at Newberry Animal Hospital says I might get my splint off this week. I sure hope I do since I am so tired of being locked up in the Clinic. I have a new appreciation for horses on stall rest. It’s NO fun!!!!