Happy Thanksgiving from the counter top!!  I hope everyone had too much to eat.  I got a plate of leftovers from Dr. Lacher and boy they were good.  My broken foot is coming along well.  I have a recheck visit Tuesday to get my splint redone.  In the meantime I feel much better when my tummy is rubbed followed by treats in case you should stop by the office this week, hint…hint…Anyway on to the topic at hand this week:  Laminitis

Dr. Lacher and Shawn Jackson recently attended the Laminitis Symposium in Palm Beach.

We will start with new therapies.  There was lively discussion regarding Platelet Rich Plasma (PRP) and Stem Cells.  There was some excellent work showing Stem Cells to be a potentially effective part of therapy for the worst type of laminitis known as sinking.  This typically occurs in very sick horses.  This form of laminitis involves failure of the lamina around the entire hoof.  Stem Cells were one component of aggressive therapy and it is important to note success rates were still only around 40%.  Other treatments used alongside stem cells included very specific trimming methods based on x-rays of the hoof and full hoof casts.  PRP was also discussed as a therapy for laminitis both early in the disease and in older, chronic cases.  PRP is thought to provide the framework for a horse’s own stem cells to settle on.  PRP also releases signals which call stem cells to the area.

Foot casts were also talked about as a way to support the chronic laminitis horse.  In fact, Dr. Lacher has already placed them on one horse.  They allow us to fully support the foot and transfer weight to the fetlock.   Chronic laminitis is always about trying to get the foot to grow out, supporting the hoof and keeping infections at bay.  This leaves the infection part to deal with.  Maggots are excellent for use as a therapy in this area.  Dr. Lacher has used medical maggots for this purpose before and learned several new uses while attending the conference.  One case used maggots to treat a deep puncture wound from a nail!

Many of the laminitis cases we see are because our horses have a metabolic disorder such as Cushing’s or Equine Metabolic Syndrome (also known as Insulin Resistance).  Dr. Nicholas Frank, a leading researcher in this area, talked about his experience managing a herd of affected horses.  One of the biggest things he learned was that horses with Equine Metabolic Syndrome are MUCH more susceptible to Cushing’s disease at younger ages than normal horses.  He found Cushing’s in horses as young as 12 years!!  Dr. Frank believes this is secondary to oxidative changes or perhaps insulin stimulating overgrowth in the pituitary gland.  The important take home point was to monitor insulin levels in suspected horses, control diet in affected horses and test for Cushing’s early in this population.  Because of discussion with Dr. Frank, Dr. Lacher added our Senior Preventative Package to the Springhill Equine Wellness Program.  She feels this will help us identify Metabolic Syndrome and Cushing’s horses early.  Radiographs of the front feet are included to help us identify subtle coffin bone angle changes and institute therapeutic trimming or shoeing before your horse has a crisis.

That is just a start of what Dr. Lacher and Shawn learned at the Laminitis Symposium.  It was an amazing group of some of the best researchers on laminitis!  For an added bonus ask Dr. Lacher about the research on the wild horses of Australia.

That’s the musings from the counter top this week.  Well the bench actually.  I can’t jump all the way up to the counter top right now.  May your food bowl be full and your litter box clean!

Tony here.  Having a rough week at the office.  Teeny cat and I got into a fight last week – she bit my foot and the vets are saying I broke two bones!  I had to go to Newberry Animal Hospital, got put under anesthesia, and had a horrible splint put on my foot!!  Woe is me! On the upside, I spent a weekend in a bathroom kitty condo at Dr. King’s house, got a new fluffy bed, and am getting many pets.  ::Sigh::  Anyway, enough complaining, we’re supposed to be chatting about CSM – part two!

Last week, our blog was introducing CSM, a group of orthopedic disorders that happens in the neck of the horse, causing neurologic signs similar to EPM.  Scroll down to read last week’s blog on Type I, which generally occurs in young horses.  Type II CSM occurs in older horses as a result of arthritis that occurs at what is called the articular facets.  Facets are normal bony projections off the main body of the vertebra – in horses, the facet from one vertebra forms a joint with the facet from the next vertebra.  When arthritis forms at this joint, the horse becomes stiff and has a hard time turning his head from side to side.  Eventually, the arthritis becomes advanced enough that it results in compression of the spinal cord, causing neurologic signs. This type of impingement is static – meaning it does not generally change with head position.  Like type I, this is a problem with cartilage and bone development. The arthritic bone is very brittle and may fracture off small pieces, resulting in further pain and worsening of clinical signs.

Symptoms generally start with signs of ataxia, dragging the back feet, and hind end weakness, similar to type I.  A “pacing” walk may be seen, and the signs may be asymmetric (eg, your horse may be stiff turning his head one way, but not the other).  The horse may have trouble getting over fences or begin tripping in the front end.  In this respect, shoeing can help tremendously.  By using a world wide racing plate, you make it easier for the horse to pick his foot up (like when you wear a pair of Sketcher’s Shape Ups!), and often times, the greatly reduces how often the horse trips.  Like type I, diagnosis is based on neck radiographs that we perform at the clinic.  Treatment is palliative – anti-inflammatory medication such as phenylbutazone (Bute) or banamine help manage the pain and inflammation.  Facet injections (performed at the clinic under sedation, and with ultrasound guidance) help to reduce inflammation in the joint, and can make your horse more comfortable for months or even years.  If you are interested in having your horse evaluated for possible CSM type II, you should consider bringing your horse to the clinic for the neurologic evaluation.   as we can then perform neck radiographs and injections the same day!  Thanks for reading, may your litter box be clean and your food box be full!

Hello there!  Welcome back to my corner.  When it comes to neurological disease in the horse, there are two syndromes you should be familiar with. They are both diseases caused by spinal cord compression in the neck, and can exhibit symptoms very similar to EPM, West Nile Virus, and other infectious causes of neurologic disease. Cervical stenotic myelopathy (CSM), formerly known as “Wobbler’s syndrome,” exhibits two forms – type I and type II.  This week we will discuss Type I CSM, which is the “classic Wobbler’s,” and next week we will discuss type II – seen in older horses as a result of neck (cervical) arthritis.

Type I CSM, also called Cervical Vertebral Malformation, is most commonly seen in horses less than five years of age.  In every species, there is a canal that present in each vertebra, called the spinal canal, that houses the spinal cord. These holes must line up and be of sufficient width to allow the spinal cord to run straight through the spinal column without compression from the bony tunnel.  This is exactly what goes wrong in horse with Type I CSM.  Sometimes the canal in the vertebra narrows, sometimes it is shaped like a cone, or it can be elongated.  These changes are a result of a developmental orthopedic disease in the vertebra, in the same group as OCD, contracted tendons, and bone cysts.  As a result, the horse has compression of the nerves that run along the outside of the spinal cord to their legs.  In general, the nerve compression that occurs is worse in a flexed neck position, and so we call the narrowing “dynamic,” or changing.  Rapid growth and large size are risk factors for this type of CSM, as are high protein and caloric intakes.  There may be a genetic predisposition for this disorder as well. Thoroughbreds, Warmbloods, and Tennessee Walking horses are significantly more likely to be affected than Quarter horses, Standardbreds, and Arabians.

Clinical signs often manifest first as evidence of weakness in the hind end.  This is because the nerves running to the hind legs are to the outside of the nerves running to the front legs in the spinal cord.  Ataxia, spasticity of the limbs, and weakness may start insidiously or suddenly.  Sometimes a history of a fall confuses the diagnosis (was the fall the cause or result?), and clumsiness and tripping is commonly reported.  Changes may first be noticed by your farrier when he is trying to trim the back feet. A pacing gait may also be present. Diagnosis is based on a complete neurologic exam where the neurologic deficit is localized to the neck, followed by neck radiographs.  Sometimes it is necessary to inject contrast dye into the space outside the spinal cord (contrast myelogram), and then radiographs show a narrowed or “pinched off” area where the dye can’t pass through the compressed area.  Often the CSF analysis is normal.

Prevention of Type I CSM is aimed at limiting protein and caloric intake to regulate growth.  Suspected horses less than a year should be weaned and placed on a “Paced Diet,” including free choice grass hay and limited amounts of growth diet and/or ration balancer to provide necessary vitamins and minerals. Foals should be confined to a stall or small paddock to restrict exercise, certainly not free-choice pasture.  Intra-articular (joint) injections with steroids can be performed on the affected neck joints under ultrasound guidance, providing symptomatic relief (will be discussed in more detail next week).  Finally, surgical correction can be performed for affected horses.  A metallic (steel or titanium) cylinder or basket is placed between the vertebrae – the goal is to induce arthritis, fusing the joint between the neck vertebrae (as we fuse hock joints in cases of advanced arthritis).  This makes the joint more stable and minimizes dynamic compression. It has been found to improve the neurologic status in 44-90% of horses with dynamic compression.

Please contact us if you would like more information on diagnosis, prevention, and treatment of CSM Type I. As always, may your litter box be clean, and your food bowl be full.  Thanks for stopping by!

Every time we change clocks around here Dr. Lacher starts to go on and on about checking fecal egg counts on our patients.  It always makes me wonder what happens when they clean my litter box but Dr. Lacher told me she doesn’t work on cats, only snuggles with us.  I did get her to answer about fecal eggs counts on horses and thought I would blog about it this week so here goes:

Around the early 1980s a revolution happened in equine parasite control:  Ivermectin.  With the use of this drug, horse owners could easily and safely remove parasites from their horses on a regular basis.  Doses of up to ten times normal would not cause problems and since it was a new class of drug parasites were annihilated.  Horse owners were happy, horses were happy, drug companies were happy and veterinarians were happy they no longer had to tube deworm.

We traveled along in our little universe until the late 1990s thinking everything was great and fine.  Worms were a thing of the past and we should keep our horses healthy by deworming every 6-8 weeks.  Sure resistance could be a problem but we just rotated products and that was that.

And we were wrong, very, very wrong.

Dewormers all have what is known as an egg reappearance period.  This is the time it takes to begin seeing parasite eggs in a fecal egg count after administering a product.  For Ivermectin this is 6-8 weeks, fenbendazole and pyrantel 4-6 weeks and moxidectin 10-12 weeks.  You should never administer a dewormer sooner than its egg reappearance period and ideally it should be at least double that time frame.  So by using Ivermectin too often we were killing off any and all sensitive parasites and only allowing the ones resistant to treatment to survive.  We were creating super worms!

Most of us do not have these super worms on our properties and can avoid their creation through intelligent deworming using fecal egg counts.  And here is where we get back to changing your clock and checking a fecal.  Turns out in Florida we kill off a tremendous amount of the parasite load during our very hot summers.  Parasite eggs cannot survive prolonged temperatures over 85 degrees.  Once temperatures have decreased below 85 degrees for about 7-10 days in a row we have the potential to drastically increase our horse’s exposure to viable parasites!  This means that if we check a fecal now and determine our horse’s parasite burden we can ensure they are treated effectively through our prime parasite season.  By checking their burden again in the spring we can maximize the effects of a final deworming before warm temperatures decrease the need for drugs.  This allows us to deworm only the horses that need it when they need it with the drug they need.

The next way we minimize resistance among the wee beasites is by keeping a low worm burden in our horses.  “Whoa!” you say my horse is not going to have any worms!!  Our horses were designed to have a low parasite burden and do just fine as long as the numbers don’t get too high.  In fact recent research has shown low levels of intestinal parasites to be important in combating diseases of the immune system.  More importantly for this topic, by keeping a small amount of worms around we ensure that resistant and non-resistant parasites breed, creating offspring who are susceptible to our deworming drugs.  So again, fecal egg counts help us identify only those horses with very high burdens and target only them for therapy.   This reduces the number of parasites exposed to drugs unnecessarily.  This is known as refugia for those scientific types who enjoy spending time on Wikipedia.

Fecal egg counts also allow us to check for resistance to drug classes.  When performing counts we always recommend a recheck fecal on any high shedders 10-12 days after dewormer administration.  This allows us to make sure there was a significant drop in egg counts.  If there isn’t, we know resistant parasites are a problem and we can take steps to address this very serious issue.

Deworming has definitely gone from a one schedule fits all to a customized program for you, your horse and your property.  The Doctors and Technicians at Springhill Equine have been great about answering my questions while I supervise from the counter and I’m sure they would answer yours as well!

That’s all from the countertop this week.  May your litter box be clean and your food bowl full!!