NCDA& CS Press Release FOR IMMEDIATE RELEASE
WEDNESDAY, APRIL 1, 2009
Equine owners should vaccinate against WNV, EEE
RALEIGH – Agriculture Commissioner Steve Troxler reminds equine owners that now is the best time to vaccinate their horses, donkeys and mules against West Nile virus and Eastern Equine Encephalomyelitis.
State Veterinarian Dr. David Marshall said these diseases are now endemic to North Carolina, but they are easily preventable.
“We haven’t had a lot of cases of EEE or West Nile the past few years, but the disease cycle ebbs and flows in our state,” Marshall said. “Horse owners should not let down their guard. They should continue to vaccinate against these diseases, and take other precautions to minimize standing water that would allow mosquitoes to breed.”
In 2008, North Carolina had 12 reported cases of EEE in horses, and 11 of them were fatal. It is estimated there are as many as four unreported cases of EEE for every one that is reported.
Horse owners should talk with their veterinarians to determine the best time to start the vaccination process for EEE and West Nile virus. Both vaccinations initially require two shots, 30 days apart, for horses that have no prior vaccination history. Neither vaccination fully protects the animal until several weeks after the second shot, so it is best to vaccinate as early in the mosquito season as possible.
Marshall recommends a booster shot of each vaccine be given every six months in North Carolina because of the extended active mosquito season.
Symptoms of WNV in horses can include loss of appetite and depression, fever, weakness or paralysis of hind limbs, convulsions, impaired vision or hyper-excitability.
Symptoms of EEE, also known as “equine sleeping sickness,” include impaired vision, aimless wandering, head pressing, circling, inability to swallow, irregular staggering gait, paralysis, convulsions and death.
People, horses and birds can become infected from a bite by a mosquito carrying the diseases, but there is no evidence that horses can transmit the virus to other horses, birds or people through contact.
Richard A. Mansmann, VMD,PhD
Director of Outreach
EHP
Stallion to Gelding Support Press Release
China Grove, NC January 21, 2009 - Horse Protection Society of North Carolina, Inc., a nonprofit equine rescue organization, is proud to announce the launch of a new program, Stallion To Gelding Support (SGS). The purpose of this unique program is to provide free gelding services to those unable to afford the procedure themselves in an effort to reduce the number of unwanted births.
More info here
Update on Atypical Myopathy: January 12, 2009
I am sad to report that another horse has succumbed to atypical myopathy in our region. This horse was seen in early December, and was a client of Dr. Beverly Hargus. The affected horse was an 18-month old TWH filly located off of Fruitland Road near Hendersonville, NC. She was reportedly fine the night before, and was found dead in the pasture the next morning. On autopsy at the diagnostic lab in Arden and on histopathology in Raleigh, lesions matched those of “atypical myopathy”. Of the owner’s 5 remaining horses, two more were treated for suspicious illness a few weeks later, but recovered without incident. The Horse website has an article at the following link, although some facts are incorrect: http://www.thehorse.com/viewarticle.aspx?id=13381. We will keep you posted as we learn more.
Ordering Medications and Supplies
In order to streamline our inventory control we ask that you keep track of any medications or supplies you will need. We know how busy everyone is these days but if you can give us a few days notice, we can order whatever you need and get it to you in plenty of time before you run out. We are working on linking our suppliers to our website so that you can order whatever you need online. We will let you know as soon as that service is available.
News Alert - November 2008
UPDATE: Wednesday, November 26, 2008
Dr. Votion from Belgium has provided us with several articles that contain suggestions for “prevention” of atypical myopathy.
The following is from her email response to us:
“In Belgium, outbreaks have ceased after several days of deep freezing and/ or when the snow covers the pastures. The best advice would be to change the pasture to use “dry” and flat pastures as soon as a case is suspected and once a case has been confirmed, the pasture should be definitively considered at risk and should only be used during dry and hot summer. If no other pastures are available, at least the access to the humid area should be restricted during the risky periods (i.e. when a lot of rain is expected). Indeed, determining the true incidence of atypical myopathy, associated risk factors or its aetiology is difficult because of the unpredictability of outbreaks and the short duration of illness. Differences between countries in atypical myopathy-associated risk factors should exist since the flora, pasture characteristics and management of horses and pastures may differ markedly. Comparison of outbreaks within countries will be of value to narrow the common factors between affected areas. This will be of great help in our quest for the aetiological agents and strengthen our knowledge of epidemiology.”
Also, she provided a link to her website: http://www.myopathieatypique.be
There are still no easy answers, especially since these are the first cases in our region. Most of our clients have turned their horses back out to pasture at this point in time, but we are recommending plenty of hay supplementation to avoid/reduce exposure to overgrazed grass roots and soil.
Frozen ground and snow appear helpful in killing the toxin, but with our frequent freeze/thaw cycles, it will be difficult to predict the safety.
Please pass this information and the article links on to other horsefolks in the community. Thank you!
UPDATE: Wednesday, November 19, 2008
Dr. Stephanie Valberg from the University of Minnesota has completed analysis of muscle samples from affected horses. She has concluded that the lipid (fat) deposition pattern in certain muscles matches the cases of “atypical myopathy” that she saw in Minnesota. She suggested some further testing at the medical school in Baylor University on plasma and urine samples to look for consistent results there as well. At this point in time, “atypical myopathy” is our working diagnosis, and these most recent results strongly support this theory.
We have now “crossed the pond” with this info and are in contact with Dr. Dominique Votion in Belgium. She authored the major report in Europe about these cases and has data from over 200 affected horses. We will be taking more samples (grass roots, soil) as needed.
Our main question to her is the same one that we have been hearing from you. “When is it safe to return horses to pasture and a normal routine?” We will hopefully get some sense of timing of her cases (within one week/month/etc) and also some more detailed description of the associated weather patterns.
The families who have lost horses are continuing to show their true colors by allowing various experts access to their property and financing seemingly endless tests and sample analyses in order to get some peace of mind and prevent further illnesses. Please keep them in your thoughts.
UPDATE: Monday, November 17th 2008
No further cases of toxin-related illness or death have been reported since Monday, November 10, 2008. Four horses in total have passed away or been humanely euthanized.
Some information from testing facilities and pathology is beginning to come in and provide some rule-outs of possible causes. Feed samples from pelleted feed given to affected horses contained no traces of monensin (a cattle growth additive that is very toxic to horses)at NC State Lab and PA State Lab. Also, the feed mill is doing their own sampling in conjunction with the NC state laboratories, but has reported a wide timeline between the mixing of cattle feed and horse feed at the mill. Stomach contents from one of the affected horses is also being analyzed and results are pending. At this point in time, monensin contamination is an unlikely cause of death in these horses. Monensin is in a class of substances called ionophores that fit well with the clinical signs and bloodwork seen.
Botany experts and NC agriculture extension agents went out to the affected farms to survey pastures and look for toxic plants. Suspicious samples were retrieved for further identification. White snakeroot (Eupatorium rugosum) contains trematone as the toxic substance and causes signs similar to ionophore toxicity. No plants of this species or any other toxic plants were identified that appear to be causative agents. Dr. Anthony Knight, a plant toxicologist and professor of large animal medicine at Colorado State, has also been consulted regarding toxic plants.
All four affected horses were autopsied, and were found to have extensive skeletal muscle necrosis (death of muscle tissue) and mild cardiac (heart) muscle necrosis, which were expected results based on clinical findings. On histopathology (microscopic analysis of tissue samples), the pattern of necrosis was not consistent with white snakeroot toxicity. Dr. Richard Oliver at the NC diagnostic lab in Arden and pathologists at University of GA are working in concert on these cases. Further histopathology samples on other organs and tissues are pending. Frozen samples have been submitted to Dr. Stephanie Valberg, a specialist in equine neuromuscular disease at the University of Minnesota CVM. She has dealt with several similar cases over the past few years, and will be comparing the tissues from NC with her cases.
Based on these findings, and many consults with experts from around the country, our top diagnosis is "atypical myopathy". Although a definite toxin has not been identified, it is most likely a fungal toxin located in the base of the root of the grass or in the soil (may also be bacterial). Certain weather patterns have been corrolated to outbreaks of cases, including cold weather with occassional moisture. At this time, our recommendation continues to be keeping horses off of pasture, and making plenty of hay available.
Updates will continue to be posted here as we receive information about this frustrating and scary situation. Thank you.
Karen Smith Reynolds, DVM
Appalachian Equine Mobile Vet Services
Barnardsville, NC
Pasture Associated Toxin
Wednesday, November 12th 2008
Two of our clients in the Cane Creek area of Fairview have suffered devastating losses over this past week. The first case was seen on Thursday, November 6, 2008 and the most recent case presented on Monday, November 10. Four horses in total were affected, and all four have since passed away. Our hearts go out to the horses and owners, and we are working tirelessly to figure out the exact causes and prevent any further deaths.
Two of our clients in the Cane Creek area of Fairview have suffered devastating losses over this past week. The first case was seen on Thursday, November 6, 2008 and the most recent case presented on Monday, November 10. Four horses in total were affected, and all four have since passed away. Our hearts go out to the horses and owners, and we are working tirelessly to figure out the exact causes and prevent any further deaths.
For the time being, we are recommending to all clients residing in the Fairview and Fletcher area that they keep their horses off of pasture and restrict any access to grass. If possible, please feed ample hay and keep horses stalled or in a drylot. Horse owners in other area of Western NC may also choose to keep their horses off of the grass to be safe.
The most likely culprit is a toxin that is being produced in the pasture by a mold or bacteria. The recent weather conditions may have allowed a bloom in the population of the organism and production of the toxin on the grass. Please see attached articles for further description of this syndrome, called “Seasonal Pasture Myopathy” or “Atypical Myopathy”. Other possible causes include toxic plants or contaminants, but these are systematically being ruled out.
This illness affects the horse extremely rapidly. The horses that we have treated were typically sweating profusely, acting very lethargic or “sedated”, showing signs of discomfort similar to colic (laying down, stretching), and walking with a stiff gait or reluctant to move at all. All four were treated aggressively by lavaging stomach contents, introducing a toxin-binding agent into the stomach, and were referred to a nearby hospital where copious amounts of IV fluids were administered. Despite all efforts by the owners and veterinarians to save these horses, none that were affected survived. Autopsies were performed on all of the horses, and final results are still pending. Several feed and plant samples were also collected for analysis, and results are also pending.
Please rest assured that we are working around the clock to determine the cause and prevent any further problems. As fellow horse owners and as doctors, we are all heartbroken by these losses. We have involved local botanists and pathologists, and are working in conjunction with experts at several veterinary colleges nationwide to figure this out as soon as possible. Please check back at this website for posted updates – we will pass the information on to you as soon as we receive it. Please pass this information on. Naturally, in a crisis situation such as this, rumors are quickly being spread. Please refer your concerned friends and neighbors to this website for the most up-to-date information.
- Further Atypical Myopathy Information (added 11/24)
Wednesday, August 20th 2008
Dr. David Pugh gave an entertaining and informative lecture on “Encephalitis and Neurologic Disease in Horses." Special thanks to Fort Dodge Animal Health & Butler Animal Health Supply for sponsoring this event.
NOTE: There will be many more events, information sessions, and special training demonstrations. Check this page for any future events.