NEW UPDATES: 1/31/2012
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Recently six horses from Virginia have be confirmed positive for EHV-1. We are recommending that you monitor your horse for fever, water and food intake, and any other signs of ill health. If you wish to have your horse vaccinated for Rhino, please call the office to schedule an appointment.
11/18/2011
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1. Frontline Spray is now available!
2. Worming update: Don’t forget even if your horse is on a fecal check worming plan you will need to worm your horse(s) with an Ivermectin wormer after the first frost (sometime after November 15) to kill bots (fecals do not check for these).
3. Blanketing guidelines: If your horse is healthy, of good winter weight, not clipped, and has shelter from the elements out in the field they will not need to be blanketed. Just remember to cool them down properly after your workouts.
4. Check water heaters now to make sure horses have a constant supply of water.
5. This is TICK SEASON! Lymes disease is a big problem in Northern Virginia and Maryland. Check your horses for ticks and use a tick repellent. If you don’t want to use the chemical Fipronel (in Frontline Spray) we have an organic tick repellant in the office – just call us to order.
6. Winter is hay season. Make sure the hay you feed is low in dust and it should smell good. This is also a great time to have your horses teeth checked and floated if needed to better chew all that hay. Dr. Froeling offers hand and power floating. Just call the office at 540-937-1754 to schedule an appointment.
Updates: August-September 2011
Due to the recent earthquake we've had several calls regarding nervous/anxious dogs. We recommend giving an herbal remedy called Rescue Remedy. It can be purchased at most health food stores, Whole Foods, GNC, etc. By giving 1 full dropper orally or 10-15 drops in the water bowl once per day it should help relax your concerned canine friend. Rescue Remedy is a completely natural supplement made from 5 different flowers and it will not affect any other medications your dog may currently be taking.
Regarding Lyme Disease - Available now is a new, more specific Lyme test for the low grade chronic form. Anyone who has gotten this test for their animal and received borderline results should consider retesting. Give the office a call if you'd like to set up an appointment or have any questions!
Beware of Summer Heat and Humidity
Summer in the DC metro area is brutal, provide run ins, or tree cover for pastured horses. If they’re in the barn during the day have multiple fans, and keep a thermometer to check the temperature if its over 90 degrees it’s a problem.
Check your horses breathing and sweating abilities, hose and sweat scrape them if needed. Horses with respiratory problems are effected first. Acupuncture and herbs can help relieve the effects of asthma (COPD) and non-sweating (anhydrosis).
Cooling Foods
If your horses are feeling the effects of the heat try feeding some cooling foods. In Chinese medicine all foods have an energetic temperature. Consider giving barley a cool grain instead of oats during the summer. Also, treats of cucumbers and watermelon can help relieve the summer heat.
Rain Rot, Skin Scurf, Dew Poisoning: The Many Faces of Dermatophilus Concolensis
Dermatophilus Concolensis is a bacteria that is responsible for most causes of skin irritation in this area. Sweat provides the moisture that allows the bacteria to spread on your horse’s skin. It can cause a folliculitis (a deep pore infection) that leads to scabs and crusts and can be very painful if curryed vigorously or picked off. The best treatment for thick scabs and crusts is Betadine Solution (not scrub) and Vaseline mixed together. Coat the effected area, cover it with saran wrap, then a polo or light blanket overnight or during day (when ever stalled), hose off crusts the next day, then use a tea tree oil spray or other effective treatment. If the area is still raw after this treatment give the office a call to schedule an appointment.
Gatorade for Horses
As you grab a Gatorade or PowerAde etc. from the fridge to help you cope with the hot weather remember to get some for you horse. Electrolytes: powder, paste, blocks, can help your horse manage all the sweat they need to stay cool and it helps prevent tye up and other muscle problems the heat can cause. If you mix electrolytes in their water also have fresh water available.
We now offer digital x-rays for immediate results! Within minutes we are able to pinpoint an issue, make a diagnosis and a plan of action to resolve the problem. We also work with the Metron Block which is very helpful for farriers in that it has exact measurements and drawing tools that aid in the correct and specific trimming of your horse’s hooves. If you’d like to set up an appointment please contact us at 540-937-1754 or fullcircleequineservice@gmail.com.
De-worming Schedule
De-worming recommendations have changed recently. It is now suggested that routine fecal exams followed by the targeted de-worming of the detected parasites replace the routine administration of chemical de-wormers. This new process should reduce the resistance to chemicals that parasites are developing. Full Circle Equine Service offers fecal exams and de-worming advice for 1 or 100 horses. We also offer herbal de-wormers and non-chemical management programs. Call the office at 540-937-1754 to set up an appointment.
AVID – Microchip
Micro-chipping your horse, dog, or cat is highly recommended. It is proof of ownership that will hold up in court. The current $40.00 offer saves you up to $50.00 off micro chipping and registration.
The New Parasitic Threat
Understanding biology is key to battling the emergence of resistant parasites in horses.
By Ed Kane, PhD
Contributing Author
For the past several decades, anthelmintics have fought off equine intestinal parasites. In recent years, however, things have changed, as some of these parasites have risen to what veterinary expert Dr. Ray Kaplan calls “the chemical challenge.” “Today most horse owners continue to follow recommendations that are based on knowledge that is 30 to 40 years old,” says Kaplan, DVM, PhD, Dipl. EVPC, and associate professor at the University of Georgia, College of Veterinary Medicine in Athens, Ga.
To complicate the issue further, the parasite of dominance has also shifted. According to Kaplan, prior to the early 1980’s, large strongyles, including Strongylus vulgaris, were the dominant intestinal parasites seen in horses, frequently causing colic due to their migrating arterial stages. Since that time, however, he explains that cyathostomes (small strongyles) have emerged as the leading culprit, frequently accounting for nearly 100 percent of the strongyle worm egg output of grazing horses – and recognized today as the principal parasitic pathogen of the horse. “Contributing to the pathogenic potential of these parasites is the problem of drug resistance, which is now reaching alarming levels,” Kaplan cautions.
Anthelmintic-resistant cyathostomes are now highly prevalent in horses. Even where drugs are stiff effective, the egg reappearance period (ERP) following treatment has become significantly shorter. Despite this reality, one positive fore the horse world is the fact that small strongyles have a relatively low level of pathogenicity. “If they were more pathogenic worms, we would have been in a huge world of hurt in the equine industry a long time ago with all the resistance we have,” says Kaplan.
Now that we’ve had a quick history lesson on where we’ve been on this subject, let’s take a closer look at the current state of the deworming debate. (Note: The following discussion pertains to adult horses only. Treatment regimens and concerns for foals and yearlings are substantially different than those for adult horses.)
Resistance is inevitable
The development of resistance can’t be stopped, but veterinarians can control it, Kaplan says. The nature of the biology of genetic selection fore resistance in parasitic worms can even be described mathematically, explains Kaplan. “It starts out being a very rare trait – and is invisible – as it initially increases over time,” he says. “Every time you treat, you’re increasing the relative number of resistant worms by killing off the susceptible worms. By the time you’re seeing decreased efficacy of the drugs, you’ve passed the threshold – and there is nothing you can do to change the course of the development of resistance.”
At this point, the game is basically over. To combat resistance before reaching the threshold, you must change the selection pressure you’re putting on the parasite population. “In regard to treating cyathostomes with ivermectin and moxidectin, we’re not at that end point yet, though it appears we’re getting close,” says Kaplan. “For now, we don’t know how close we are. However, based on all appearances – with eggs coming back faster and faster after treatment – it looks like we’re finally to a point where ivermectin – and moxidectin-resistant strongyles are a realistic inevitability in the near term.”
Consequently, Kaplan has submitted a grant for a research project to commence in 2010 that could help us understand how close we actually are.
Modernizing control
It’s important for equine practitioners to be educated on parasite biology in order to deal with the emerging issues surrounding parasite control practices effectively. When it comes to developing a treatment approach, veterinarians must remember that every horse is infected with cyathostomes in different stages of development.
For example, disease (when seen) is not caused by adult worms, but rather by larval worms emerging form the mucosa, causing lots of gastrointestinal damage. We see this all the time in horses at a subclinical level. If you see eggs in a horse fecal sample, that means there are adult worms in the animals’ gut – and somewhere in the recent past the larvae came out of the mucosa. Even so, as long as the population is maintained at a biological equilibrium, it causes very little health damage to the horse.
“Nearly all anthelmintics fail to kill the encysted larval forms that are causing the pathology,” says Kaplan. “Therefore, when you deworm a horse, you are only killing the stage of the parasite that is not really harming the horse – the adult parasite.”
The benefits of this approach, says Kaplan, are that you’re decreasing the amount of egg shedding that is occurring onto the pasture. Decreasing egg shedding (and therefore preventing future infections) is beneficial to promote the health of horses as well as to provide equine practitioners with a strategy to slow down the resistance.
About 50 percent to 60 percent of all the adult horses have very low egg counts (less than 200 eggs per gram). In fact, many of them will have egg counts of either zero or approaching zero, whether you treat them or not. Therefore, those horses don’t need to be treated very often. Because they are not shedding many eggs onto the pasture, they just need one or two properly timed treatments during the year.
The bottom line is that the threat of worms to the health of an adult horse is highly overrated. If most adult horses were never treated for small strongyles in their lifetime, they would probably appear perfectly healthy. However, a certain percentage of horses are more affected than other – these animals, which amount to approximately 20 percent of horses, may develop clinical signs if you don’t control the parasites. “As we get more resistance and treatment failures, those are the animals that are going to start showing the problems,” cautions Kaplan.
Treating by necessity
Although they only amount to about 20 percent to 30 percent of the animals, high egg shedders distribute more than 80 percent of the eggs onto the pasture. By treating these animals more intensively, you not only help them directly, but you also help other horses indirectly, by not allowing the heavy egg shedders to contaminate the pasture. “By using a selective treatment approach, the more heavily parasitized horses that need the treatments will get them,” says Kaplan. “Less treatments are given to the horses that don’t need to be treated.”
By not treating the low egg shedders, you’re allowing them to contaminate the pastures with a relatively small number of eggs. Therefore, you’re not applying any selection pressure for resistance on the parasites from the low egg shedders. ON the other hand, if you treat the high egg shedders with drugs shown to be effective, you can decrease total egg shedding by as much as 95 percent.
If you’re using a drug such as ivermectin or moxidectin, which should decrease the egg counts by 99.9 percent, then the treated animals are shedding only a small fraction of all eggs on the pasture. Therefore, if you treat half the animals with these effective drugs – and do nothing with the other half (low egg shedders) – you will decrease the total egg shedding by about 95 percent. After treatment, about 98 percent of all the eggs with be shed by the untreated animals, supplying what is called “refugia,” the non-drug-selected portion of the population that helps dilute any resistant worms.
By following this regimen, the evolution of resistance is greatly slowed. Although there is still selection toward resistance taking place, it’s occurring at a much slower rate, because you’re allowing all of the unselected refugia to remain in the overall parasite population. This concept is the key idea behind the selective treatment of high versus low egg shedders. Not only does it prevent a lot of unnecessary treatment, but it also allows you to focus your treatments on the horses that really need it – and slow down the progression of resistance in the process.
Checking egg counts
The overriding theme of horse parasite control is an irrational fear of horse parasites dating back to the 1960’s. Horse owners and veterinarians have fallen into the same trap – a paranoia of horse worms. The belief is that we have to treat frequently; otherwise, our horses are going to get sick and die of worms. We think that if we don’t treat, we are either being negligent owners, or we, as veterinarian, might be liable for horses that get sick and die. The traditional deworming strategy does not match the reality of the biology. That’s why a change is necessary, Kaplan says.
Once owners and veterinarians start checking egg counts, which is the key to success, they’ll see that many of their horses most often have zero egg counts, leading them to question, “Why am I having to treat him all the time?” Or it they use a drug and do an egg count before and after treatment – and realize that the egg count did not decrease – then they’ll ask themselves, “Why am I treating this horse with drugs?”
Winds of change
Once members of the equine community realize that these horses are healthy after six months without treatment, they will start to realize the futility of their former approach. However, this change in mindset doesn’t come easy – it requires a total shift to initiate change.
This trend has already begun, Kaplan says. “Recently, increasing numbers of veterinarians are picking up on this message and modifying their thinking and approaches about deworming,” he says. “We’ve got a long way to go, but in the last year or two we’re actually starting to see a shift, which is encouraging.”
Because moderate control efforts will keep adult horses healthy, it’s unnecessary to treat every two months. For about 50 percent of horses (low egg shedders), a treatment once or twice per year is adequate. For the 25 percent of high egg shedding horses need four to five treatments per year. In addition, it’s important to remember that climate and type of dewormer used also affect the outcome.
If veterinarians continue to apply deworming treatments to adult horses six times per year – which has become customary practice – Kaplan insists the drug resistance problem will only worsen. “Strategies to decelerate further selection of drug resistance, thereby extending the lifetime of currently effective anthelmintics, need to be implemented whenever possible,” says Kaplan. “This goal can best be achieved by treating the right horse with the right drug at the right time.” dvm
Ed Kane is a Seattle-based author, researcher and consultant in animal nutrition, physiology and veterinary medicine.