There's nothing better than hanging out with your BFF.
Thanks Patti, these two made us smile!
For over 25 years, Horsemen's Laboratory has been performing microscopic, fecal egg counts helping horse owners protect their horses and customizing an effective worm control program for our clients.
For your convenience, we have created a self contained kit that has everything you need including a postage-paid envelope to return the sample to Horsemen's Laboratory for testing. Your test results are then simply emailed to you.
Horsemen’s Laboratory is now offering EquiSal, the new antibody test for detecting tapeworms in horses using a salivary swab. We are working with Austin Davis Biologics Ltd., in Great Britain to provide the new EquiSal test for tapeworms
to our clients here in the USA.
Romeo and Mitch are a team and best friends.
There's nothing better than hanging out with your BFF.
Thanks Patti, these two made us smile!
Lucy loves frolicking in the snow!
What a great photo of a beautiful horse in an amazing setting ... thanks Patti for sharing it with us!
This big paint mare is River. Nancy grew up showing horses, but had to leave that life behind years ago. Then out of the blue a friend brought River to Nancy and said, "you need this!". Nancy wrote to Horsemen's Laboratory saying, "River is my heart and soul. My rock. My shoulder. My get away when stuff is knocking me down. She's not an expensive registered horse, but she is mine, and that's all that matters."
We agree! Great photo Nancy, thank you for sharing it with us!
Midnight is a two year old registered Tennessee walking horse stallion.
Thank you Gesnan for sending Horsemen's Laboratory this great selfie of you and your beautiful horse!
Horsemen’s Laboratory has received several requests for information about deworming and what schedule we recommend. We do not recommend any specific deworming schedule. However, we do recommend deworming according to fecal egg count (FEC) results.
The standard thought is to deworm according to egg shedding category:
Horsemen’s Laboratory recommends having fecal egg counts done every 3 months. After receiving 3 or 4 fecal egg counts with results all below 200 eggs/gm, an owner may only want to check every 6 months which is certainly reasonable.
Many owners whose horses test negative (no worm eggs found on counting chamber) ask if they should deworm their horses anyway and we recommend they should deworm at least once a year. Horsemen’s Laboratory feels the best time to deworm in these situations is in November or December in most parts of the United States. We generally recommend an Ivermectin Praziquantel combination, as this is a combination that is effective against a wide variety of worms that effect horses and whose eggs do not always show up when a fecal egg count is done. The two products found most commonly that contain this combination are Equimax and Zimecterin Gold.
Zimecterin Gold has been the focus of some internet articles that suggest it may be responsible for causing some swelling and occasionally ulceration of the lips, tongue, and gums of the horse when given. I have spoken to the Merial representative about Zimecterin Gold who said they have received reports of 1 in 20,000 doses possibly causing these problems, but have been unable to reproduce them so they cannot determine what the cause may be. I have also spoken to the United States Department of Food and Drug Administration, and they said they have also had the problem reported to them, but they did not offer any more information than that.
The above statements are generally what we recommend should be done about deworming. However, if you have specific questions concerning your horses’ worm control program feel free to contact me at: firstname.lastname@example.org or call (800) 544-0599.
Horsemen’s Laboratory offers very reasonably priced consulting services, for more information, please check out our website: www.horsemenslab.com.
By Dr. John Byrd
This is written due to the time of year and the fact I have felt the desire to do so.
In the past most of our posts and articles that I have written were either about worms and their detection and control or answers to questions our clients have asked. This article will be about my thoughts and feelings over the years since I came up with the idea about starting Horsemen’s Laboratory. My life was changed dramatically a couple of years after I graduated from the University of Illinois school of Veterinary Medicine because I was not sure what path I should follow. This caused a severe problem in my personal life that I had to call on a higher power that I had recognized in other areas of my life years earlier, to solve the problem. The solution greatly improved my personal life as well as my professional life. What was the solution you ask? I will be happy to share the solution with you if you personally contact me.
This is about pursuing my dream of doing something I felt like was worthwhile in helping horse owners. After graduating I started a general equine veterinary practice, but soon found that I wanted to do more than deworm horses, vaccinate, float teeth, and examine horses for general problems such as colic, lameness, wounds, and respiratory problems. Shortly after I started my practice I realized what I was doing was rewarding, but did not feel fulfilling and so I sought to seek more information about keeping horses healthy and was fortunate enough to get a residency position at the University of Florida in the large animal clinic. During the time spent there I realized I wanted to specialize in some area of veterinary care that applied to horses. Upon completion of my residency at Florida I had hoped to get a job at the University of Illinois, but that did not occur.
My next stop was California where after a short stent in a group equine practice I again started another general practice. After several more years of doing what I thought I was supposed to be doing even though I still did not feel fulfilled. Again I sought more education and took the International Veterinary Acupuncture course. It was during the time that I was taking the acupuncture course that daily dewormer became available. The fact many of my clients started asking for the daily dewormer and a statement I heard during the acupuncture course made me think someone should study how many horses really needed daily dewormer. The statement was that many endurance riders felt they saw a longer recover time in their horses following deworming for up to 2 weeks. After consulting with several parasitologists that mainly studied worms in horses I decided to check horses for worm eggs before I dewormed them every 2 months. I found that less than 1 out of 20 horses were passing eggs to indicate that the horses in my practice were having a worm problem and needed the daily dewormer.
Horsemen’s Laboratory was born as a result of a question that I asked myself and the parasite experts who had consulted with previously. The question was why hasn’t someone started a laboratory to check horses for parasites instead of just deworming every 2 months and feeding daily dewormer if it is not needed. The next question I asked myself was why not me? Therefore, I began to visualize how such a laboratory service would work. The most important aspects were that the service must be convenient for owners to use, reasonably priced, and the results available in a timely fashion. After 25 years in business Horsemen’s Laboratory continues to work to improve these aspects of our service.
For the first 15 years we received very few samples; however, we had some loyal clients that encouraged us to continue and many of these clients are still clients today. I would like to take this opportunity to thank those clients as well as the clients that have just started using Horsemen’s Laboratory to evaluate their horses’ worm control programs. I cannot deny I thought that I should just quit, but I continued to have this feeling that I was doing the right thing and knew this is what I should be doing. Someone once said that if you do something you enjoy for a living you won’t work another day in your life. I have found this to be so very true over the last 5-6 years. I feel that the information we provide our clients about their horses’ worm control program is very important. I also deeply enjoy visiting with our clients throughout The United States and Canada and giving them advice about their horses’ worm control program.
I have written this because I would like to encourage my clients to seek fulfillment of their dreams and to encourage them to set goals in order to reach that point in their life where they never have to work another day.
Throughout my life I have had many clients and other people who have encouraged me and gave me advice and I deeply appreciate it and hope in some way this may help to repay them by passing it on so to speak.
By Juliet M. Getty, Ph.D.
The horse world is cluttered with feeds, supplements, and remedies all promising a better, “new and improved” horse. While many such products do in fact improve horses’ health and condition, there are certain basics that every horse needs, regardless of breed, age, condition, or purpose. Even seasonal or regional changes do not alter these foundational principles.
Water is the most important nutrient
It must be plentiful, clean, and of the right temperature to encourage horses to drink. A horse at maintenance, living in a temperate climate will require a minimum of ½ to 1 gallon per hundred pounds of body weight. For the 1100 lb (500 kg) horse, that equates to 5.5 to 11 gallons (21 to 42 liters) per day.[i] However, his demand for water will increase with activity and warmer temperatures. Here are some factors to consider:
Salt is required daily, regardless of the season
In cold seasons, salt helps promote that all-important water consumption. In warm seasons, supplemented salt replaces what is lost from perspiration. A full-sized horse requires at least one ounce (two level tablespoons or 30 ml) of salt each day for maintenance -- this much provides 12 grams of sodium. Heat, humidity, and exercise increase the horse’s need. There are several ways to accomplish this:
Forage is the foundation of the diet – it must flow through the digestive tract 24/7
Horses are grazing animals and are designed to consume forage virtually all day and night, only taking a few minutes here and there to rest; this also includes ponies, minis, donkeys, and mules. There are many reasons why your horse must always have hay and/or pasture:
Don’t let anyone scare you into thinking that feeding hay free-choice will damage your horse. Please read “Equine Digestion – It’s Decidedly Different” to empower you with the knowledge needed to help your horses.[iv] Hay testing and commercially available “slow feeders” are worthwhile for many horses.[v]
Replace what hay is missing
Many horses rely entirely on hay for their forage needs. Is hay nutritious? Not very. Hay is dead grass; it no longer contains many of the vitamins, omega 3s and omega 6s it once had as living pasture. It does, however, contain protein, carbohydrates, and minerals, and is a significant source of energy. Consider the following to fill in the nutritional gaps:
Movement, companionship and shelter are vital necessities
Horses need to move and have the protection of a buddy. Standing in a small area for hours on end (even if part of it is outdoors) takes its toll on your horse’s mental and physical health. So does being isolated from buddies. The stress can be so great that it dramatically diminishes your horse’s quality and length of life by compromising his immune system and hormonal responses. We see the effect in a vast variety of health issues:
Horses also need shelter from harsh weather. This can best be accomplished by offering your horse the option to make choices. Barn stalls that can be entered and left at will through open gates allow your horse to decide what is most comfortable.
Horses are individuals and may need additional nutrients and care, but covering the basics of water, salt, forage, necessary supplementation, movement, stress reduction, and shelter will optimize your horse’s foundation for a lifetime of vibrant health.
Permission to reprint this article is granted, provided attribution is given to Juliet M. Getty, Ph.D. No editorial changes may be made without her permission. Dr. Getty appreciates being notified of any publication.
Juliet M. Getty, Ph.D. is an independent equine nutritionist with a wide U.S. and international following. Her research-based approach optimizes equine health by aligning physiology and instincts with correct feeding and nutrition practices.
Dr. Getty’s comprehensive resource book, Feed Your Horse Like a Horse, is available at www.GettyEquineNutrition.com -- buy it there and have it inscribed by the author, or get it at Amazon (www.Amazon.com) or other online retail bookstores. The seven separate volumes in Dr. Getty’s topic-centered Spotlight on Equine Nutrition series are available with special package pricing at her website, and also at Amazon in print and Kindle versions. Dr. Getty’s books make ideal gifts—check her website for holiday specials.
Find a world of useful information for the horseperson at www.GettyEquineNutrition.com: Sign up for Dr. Getty’s informative, free e-newsletter, Forage for Thought; browse her library of reference articles; search her nutrition forum; and purchase recordings of her educational teleseminars. Reach Dr. Getty directly at email@example.com. She is available for private consultations and speaking engagements.
[i] Chastine, M.N., 2009. You can lead a horse to water… The University of Montana Western Equine Studies Program. http://www.aaep.org/info/horse-health?publication=867
[ii] University of Kentucky College of Agriculture, Food, and Environment. 2015. Blue-green algae poisoning in horses. The Horse. http://www.thehorse.com/articles/29469/blue-green-algae-poisoning-in-horses
[iii] Please read articles related to insulin resistance, overweight, and leptin resistance found by clicking on “Library” at www.gettyequinenutrition.com
[iv] Getty, J.M. 2013. Equine Nutrition – It’s Decidedly Different. Available at www.gettyequinenutrition.com or online bookstores.
[v] A variety of slow feeders is available at Dr. Getty’s Free Shipping Store: http://horsesupplements.gettyequinenutrition.biz/slowfeeders.html
[vi] Nutra Flax and U.S. Chia can be found at Dr. Getty’s Free Shipping Store. Other sources such as high-DHA algae from a vegetarian source and Camelina oil are also available. http://horsesupplements.gettyequinenutrition.biz
By Dr. John Byrd
Founder & Owner of Horsemen's Laboratory
Horsemen’s Laboratory was started in 1991 as a local endeavor in Southern California. At boarding stables we set up a system where horse owners could pick up a postage paid envelope and a container, they would then get a fecal sample from their horse and send it back in the container to Horsemen’s Laboratory to be tested.
In the fall of 1992, my wife, Becky and I decided to move back to our home state of Illinois where we owned property near the University of Illinois. There was a veterinarian at the university who was interested in becoming a partner in Horsemen’s Laboratory. Unfortunately, the business was not an overnight success and after 6 months he lost interest.
The first 16 years we struggled to keep Horsemen’s Laboratory afloat. Our clients were happy and excited to tell friends about the unique service we were providing; however, we kept hearing the same two issues. First, when they talked to other horse owners or to their veterinarian, they were told that there was no need to check for worms that they should simply deworm because all horses had worms. Secondly, we heard that people were skeptical about sending fecal samples through the mail because they were not confident that the egg count would be accurate.
In 2009, articles about parasite resistance started to appear regularly in magazines and on websites. It appeared that the number one cause of this resistance was the over exposure of worms to the deworming medication. The over use of deworming medication was killing off all the sensitive worms and leaving the few resistant ones to mate with each other, thereby, creating a larger and larger percentage of the worm populations to become resistant to the dewormer. It was proposed that only those horses that were passing worm eggs should be dewormed instead of all horses thereby cutting down the exposure rate. This practice would allow some sensitive worms to remain to mate with the resistant ones to continue a line of worms that is sensitive to the medication. As this new method of parasite control has gained favor Horsemen’s Laboratory has grown more quickly because the only way to tell which horses should be dewormed is by doing a fecal egg count.
Now even veterinarians are recommending and using our service. However, our biggest source of new clients is still word-of-mouth from our loyal clients telling friends and fellow horse owners about Horsemen’s Laboratory.
When I started Horsemen’s Laboratory my 2 main goals were to make the service as convenient and economical as possible for our clients. We also wanted to be able to get the results back to the owner as quickly as possible. Starting in 1992 we advertised in magazines and did a few horse fairs and shows to promote Horsemen’s Laboratory. We handed out a lot of testing kits to horse owners to mail their horses’ samples back to Horsemen’s Laboratory. Unfortunately, most of those kits were never returned. During the early years we sent out the testing kits in the mail and asked clients to send their payment in with the sample, but that didn’t seem to catch on. Therefore, we were out the postage and the cost of making up the kit. As a result we started having clients pre-pay for the testing kits before they were mailed out. In 1996, our website www.horsemenslab.com was created and most of our promotion has been through the website and online. In 2007, the website was enhanced so clients could order testing kits and pay for them online. Horsemen’s Laboratory also started emailing owners their horses’ results. Today 99% of our clients receive their horses’ results by email. At Horsemen’s Laboratory we continue to improve our service and make it more convenient for our clients to evaluate one of their horses’ biggest health concerns, worms.
In conclusion, we would like to thank all of our clients and especially those who started to use our service back in the early years and continue to use our service today. We deeply appreciate your loyalty and thank you for telling your friends and fellow horse owners about Horsemen’s Laboratory.
Article written by Abby Strawder
By now, many horse owners have likely heard that rotational deworming is outdated. More than half of horse owners are working with veterinarians to use fecal egg counts (FEC)1 to determine customized deworming schedules. As more horse owners turn away from rotational deworming, different questions arise around timing.
There are two main parasites – bots and tapeworms – that are targets for fall or winter timing.2
Bots are the larvae of the botfly. Since these flies are common in barns and pastures where horses live, horses could become infested with bots, and often horse owners will recognize the botfly eggs on their horse’s hair.3 Deworming with ivermectin yearly, during late fall or early winter, is recommended as a cleanout treatment for bots, which will help decrease transmission in the next season.2
Adult tapeworms are fairly common and live in the intestine of the horse;3 however, they are difficult to diagnose. Horse owners will rarely see tapeworm segments in manure, unlike some other parasites, and there is no reliable diagnostic test for active tapeworm infection.4
But because tapeworms have potential to cause disease like colic, a properly timed tapeworm treatment is beneficial.2 In most U.S. areas, deworming with praziquantel in combination with ivermectin should be given in late fall or winter.2 Cold weather means the end of tapeworm transmission, and that timing for treatment helps diminish additional transmission the following grazing season.2 No generic ivermectins offer tapeworm control.
“Parasite control is an important part of any horse health program,” says Hoyt Cheramie, DVM, MS, DACVS, manager, Merial Large Animal Veterinary Services.“Choosing the right deworming product and the right timing for it is key.”
ZIMECTERIN® Gold (ivermectin/praziquantel) is a broad-spectrum dewormer that controls more species and stages of equine parasites — including the tapeworm Anoplocephala perfoliata — than any other brand.5,6 Ultimately, each farm should develop its own program tailored to the specific needs of the farm and each animal, with veterinary guidance. There is no such thing as a “one size fits all program.” 2
More information about effective deworming strategies and ZIMECTERIN® Gold (ivermectin/praziquantel) can be found at www.rethinkdeworming.com.
Merial is a world-leading, innovation-driven animal health company, providing a comprehensive range of products to enhance the health and well-being of a wide range of animals. Merial employs 6,100 people and operates in more than 150 countries worldwide with over €2 billion of sales in 2014.
Merial is a Sanofi company.
Important Safety Information: Not for use in humans. Keep this and all drugs out of reach of children. In horses, there have been rare reports of swelling and irritation of the mouth, lips and tongue following administration of ZIMECTERIN Gold. These reactions have been transitory in nature. Do not use in other animal species as severe adverse reactions, including fatalities in dogs, may result.
®ZIMECTERIN is a registered trademark of Merial. ©2015 Merial, Inc., Duluth, GA. All rights reserved. EQUIZIM1507 (10/15)
Article written by:
Senior Reputation Manager
Sullivan Higdon & Sink
1American Horse Publications. 2015 AHP Equine Industry Survey. July 2015.
2AAEP Parasite Control Guidelines 2013, Accessed June 1, 2015. http://www.aaep.org/custdocs/ParasiteControlGuidelinesFinal.pdf
3Internal Parasites in Horses. American Veterinary Medical Association. September 2010.
4Reinemeyer C, Nielsen M, McArthur M. Parasite control as a profit center. EquiManagement. 2010;26.
5Based on data provided on the ZIMECTERIN Gold label.
6Based on data provided in FDA Freedom of Information summaries.
Dear Dr. & Mrs. Byrd and Staff at Horseman's Lab:
I have been using your laboratory services for a number of years. The addition of the consulting service along with the laboratory has been absolutely fantastic. All my barn animals - horses, donkey, goat - are in your computer system with their parasite history, so when I call to find out what worming product to give them, you have it at the touch of your fingertips. Through your consulting service, you can look at my whole herd, decide what product is best to give to which animal, and explain to me the why's and how's of parasite control. I now have a means of effective parasite management and I know you are just a phone call away.
I want to also add how very cheerful and helpful you and your staff are when I call. You all have been nothing but professional, helpful and friendly. I look forward to many more years with you at the center of my horses' health!
For more information about Dr. Byrd's consulting services visit our website: www.horsemenslab.com
Refer a friend to Horsemen's Laboratory and earn free testing kits for your horse! View and print the attached "Refer-A-Friend" slip below for more details.
CONGRATULATIONS to Carol Chang of Mahomet, Illinois. Carol was the winner of the SAMSUNG GALAXY TAB PRO 8.4 from the American Legion Auxiliary raffle. Thank you to everyone who participated in raising money for our Veterans.
By Stephen Flynn -- US Army, Retired and Freelance Writer
With strongyles posing the greatest parasite risk to horses it is important to understand how the environment factors into their development. Regardless of the time of year, it is always a good idea to have a Fecal Egg Count done on a regular time basis to ensure proper control, prevention, and treatment measures are in place. Horseman’s Laboratory is ready to service those needs.
Strongyles have a wide range of acceptable climates; they thrive best, in warmer, more humid areas. This is why warm areas with plenty of rain to grow good grass is the best place for the life cycle of small strongyles to be completed. They can survive outside throughout the colder months, even long periods of freezing temperatures hatching when the temperature reaches 7c (44F) with the ideal temperature range being between 77F to 91F (Handbook of EQUINE PARASITE CONTROL, by Dr Craig R. Reinemeyer and Martin K. Nielsen).
Small Strongyles, the most common intestinal worm have three stages, the third being the most critical to the parasite’s survival. At the third stage the worm is protected by a thin membrane, but has no mouth (Horsetalk.co.nz). It is at this stage the larvae are at their most vulnerable. During the hotter months the energy stores are consumed at a faster rate leaving the larvae susceptible to death by starvation. Colder months allow the larvae to burn the calories at a much slower rate so they last longer (Briggs, 2004). It may be a good recommendation to have Horsemen’s Laboratory do a Fecal Egg Count at seasonal changes. Once an owner has established which category their horses fit into by doing fecal egg counts they may only need to check the low shedders 2 times a year while checking high shedders 4 times a year. It has been demonstrated that 80% of the pasture contamination by strongyle eggs is from the 20% of the herd that are high shedders while the 80% of the herd that are found to be low shedders account of only 20% of the contamination.
Another environmental factor with a hand in the worm population is the grazing land. Horses tend to divide their grazing area into 2 distinct areas. One area is known as the lawn and the other as the rough. The lawn is where most horses graze while the rough is where they pass their stool. The rough naturally contains the most eggs and infective larva. The eggs hatch and develop into the third stage infective larva in 3 days, after being passed in the horse’s stool, at which time they leave the manure pile and only travel about 18 inches and climb up the grass and wait for a horse to eat them. Since most horses do not normally graze the rough areas they are somewhat protected from the bulk of the infective larva; however man and nature often disturbs the roughs spreading the infective larva into the lawn or grazing areas. Nature does this by raining and the naturally flow of the water. Owners spread the infective larvae when they drag or mow the pastures. Dragging and mowing of pastures should be done during the hot dry part of the day. The rough areas have the longest grass due to the nutrients in the manure passed there and the retention of moisture by the manure. A few horses may not be able to resist the temptation to graze in the rough areas and this may be one reason for the disparity in the fecal egg counts of horses in the same pasture.
All in all it seems pertinent to be aware of the ideal times for parasite development, spring and fall, and parts of summer in some areas of the United States. Doing Fecal Egg Counts should never be removed from the equation. In preparation for those ideal growth times, horse owners should possibly consider plans to contact a veterinarian or Horsemen’s Laboratory on a regular basis to determine which horses in their pastures are low, medium, and high shedders by doing fecal egg counts.
What about the Weather, Horsetalk.co.nz, Jan. 18, 2013 http://horsetalk.co.nz/2013/01/18/weather-and-parasites/#axzz3jJFWavSY
Strongyles: The Worst of the Worms, Karen Briggs, April 2004 http://www.thehorse.com/articles/14574/strongyles-the-worst-of-the-worms
Handbook of EQUINE PARASITE CONTROL by Dr. Craig R. Reinemeyer and Martin K. Nielsen
Article by Stephen Flynn
With the ongoing discussion about deworming intervals, we find a number of opinions advocating regular intervals or the rotation of different drugs. In the not too distant past, the common practice was to deworm on a regular basis. About every two months horses were treated to kill Strongylus vulgaris (large blood worms). In time, however, another class of worms (small Strongyles) became the most popular worm and almost immediately began to develop resistance to that treatment plan so conventional wisdom changed.
Veterinarians began using a rotational approach, alternating different drugs with each treatment as it was found the worms grew resistant with more frequent use of the same drug. This strategy worked for some time until it was determined that large Strongyles were more or less no longer a problem. This did not eliminate the problem of worms entirely; of course, it merely caused a need to focus on small Strongyles.
Another option is to treat for worms daily as a preventative measure. This seemed to control the spread of worms for the time being but now many think may be one of the biggest causes of resistance in small Strongyles?
Cyathostomins (small Strongyles) seem to develop resistance more quickly than the large Strongyles, which came before them. With this knowledge, it is time to consider a new approach. While children and horses are obviously not the same and the diseases that affect them are not the same, we still might take a page from our parenting skills booklets and consider an alternative treatment plan.
With the knowledge that horses are not all identical in their susceptibility to worm infestation and vary in the passing of eggs in their stool, it stands to reason each case (whether it be one horse or an entire herd) should be treated individually. It may also be important to take special concerns with horses not yet of adult age as they are more susceptible to worm infestations (3). This fact supports the concept of having a Fecal Egg Count done at regular intervals and providing treatment as necessary.
I spoke with Dr. John Byrd, DVM about his thoughts (Dr. Byrd is the owner of Horsemen’s Laboratory in Mahomet, IL.). While the previously used methods each had merit, he believes it may be best now to consider treating for worms according to the horse’s parasite egg shedding rate. Like with your child, you don’t run them to the doctor monthly to give them a dose of cold prevention medication. Gone are the days when a spoon of castor oil every week was thought to be a preventative measure.
Absolutely, vaccines will prevent certain viral and infectious diseases; worms are not the same and cannot be treated as such. However, if, as seen in historical data, the worms grow resistant to over use of drugs, Dr. Byrd believes we cannot depend on symptoms to determine when a horse has a parasite problem. Because most horses exhibit no symptoms of worms even when their fecal egg count is very high. By doing a fecal egg count Dr. Byrd can determine the effectiveness of a horse’s worm control program. Ideally, rather than treating regularly, you should test regularly, at predetermined intervals and once egg counts exceed a set number (generally accepted 200 eggs/gm), you would then treat based on the measure of infestation. If a horse’s egg count remains negative or under 200 eggs/gm for a year Horsemen’s Laboratory recommends deworming once a year in late fall or early winter with an Ivermectin and praziquantel combination. This program appears to be best method of slowing the development of resistance in worms to the medication approved for use in horses today. Since there are not any other medications being tested for approval at this time it is critical to slow the development of resistance to the medication we have presently available.
The next question should be, how to treat to prevent worms from becoming a problem at all in the future, or to greatly reduce the risk to a tolerable level.
This article was written by Stephen Flynn for Horsemen’s Laboratory. Stephen Flynn is a freelance writer who served in the U.S. Army and is now retired. He graduated from American Intercontinental University with a Master’s Degree.
(1) 40-Year-Old Rotational Deworming Strategy Has Led to Resistance, 7/8/2015
Abby Strawder, Senior Reputation Manager, Sullivan Higdon & Sink
http://www.equinefecaleggcount.com/ The Horseman’s Laboratory Blog
(2) Symptoms of Parasite Infestation, Dr. Madalyn Ward, DVM
Holistic Horsekeeping with Madalyn Ward, DVM
(3) AAEP Parasite Control Guidelines, Developed by the AAEP Parasite Control Subcommittee of the AAEP Infectious Disease Committee, Revised 2013
By Abby Strawder, Senior Reputation Manager
Sullivan Higdon & Sink
Fecal Egg Count Tests Should be Used to Determine Your Deworming Strategy
More than 40 years ago, traditional parasite control programs were developed involving rotating dewormers with a number of different products at regular intervals. At that time, most horse owners were concerned about Strongylus vulgaris (large strongyle bloodworm).
S. vulgaris doesn’t occur very often, thanks to the traditional approach of rotational deworming. The two-month schedule associated with rotational deworming worked well on strongyle eggs, because it takes about that amount of time for reappearance after treatment.
While S. vulgaris is no longer a large threat, according to the American Association of Equine Practitioners (AAEP) Parasite Control Guidelines, horse owners should still take action against small strongyles (cyathostomins)1. In addition, tapeworms (Anoplocephala perfoliata) have been recognized as a potential cause of colic1.
If rotational deworming was so successful, why switch strategies now? Shouldn’t those same strategies work on other parasites? The answer, quite simply, is “no.”
“Calendar-based rotational deworming is an outdated practice,” says Hoyt Cheramie, DVM, equine specialist, Merial Large Animal Veterinary Services. “That’s because the life cycles and biology of small strongyles and tapeworms are different from large strongyles, and the rotational strategies designed for them aren’t as effective at controlling small strongyles and tapeworms.”
Four decades of rotational deworming has created resistance, which is the ability for worms to survive certain types of treatments2. Small Strongyle Resistance2.
Dewormer (active ingredient) Percent of farms with resistance
ZIMECTERIN® (ivermectin) 0 percent
STRONGID®-P (pyrantel pamoate) 40.5 percent
ANTHELCIDE (oxibendaxole) 53.5 percent
PANACUR®/SAFE-GUARD® (fenbendazole) 97.7 percent
“What is needed are properly timed treatments with effective dewormers,” says Cheramie. He adds that the goal is not to completely eliminate all parasites in horses. The goal is to manage individual parasite loads to prevent health issues such as colic, weight loss and diarrhea. A secondary goal is to protect the pasture from being loaded with eggs and infecting other horses.
Fecal egg count (FEC) and fecal egg count reduction tests (FECRT) are the methods veterinarians use to determine a deworming schedule tailored to each horse while detecting resistance on farms.
“Fecal egg counts only test for strongyles; they don’t detect for tapeworms,” adds Cheramie. “AAEP recommends using a dewormer that contains an ingredient, such as praziquantel, that kills tapeworms at least once a year.”1
ZIMECTERIN® Gold (ivermectin/praziquantel) is approved to control more species and stages of equine parasites than any other equine dewormer, including those small strongyles (adults, including those resistant to some benzimidazole class compounds).3
“A fecal egg count measures the number of strongyle eggs a horse is passing in each gram of its manure,” says Cheramie. “When you send a sample to your veterinarian, you will receive a number followed by EPG (eggs per gram), which will tell you whether your horse is a high, medium or low shedder.”
What those EPG numbers mean:4
Low shedders: 0-200 EPG
Moderate shedders: 200-500 EPG
High shedders: >500 EPG
If the horse is a low shedder, that particular horse has good natural immunity to strongyles and may not need to be dewormed as frequently. However, if the horse is a moderate or high shedder, that horse may need to be dewormed more often than other horses, even if the horse shows no signs of parasitism. This helps protect the pasture from being loaded with eggs.
Resistance is highly prevalent in small strongyles and should be factored into deworming decisions.3 “To test for resistance, after your first fecal egg count test, your veterinarian will have you deworm your horse and take a second fecal egg count two weeks later,” says Cheramie. “If the egg count number has not dropped significantly from the first test, then the worms on your farm are probably resistant to that dewormer’s active ingredient.”
To learn more about modern deworming practices, visit www.rethinkdeworming.com.
IMPORTANT SAFETY INFORMATION: Not for use in humans. Keep this and all drugs out of reach of children. In horses, there have been rare reports of swelling and irritation of the mouth, lips and tongue following administration of ZIMECTERIN Gold. These reactions have been transitory in nature. Do not use in other animal species as severe adverse reactions, including fatalities in dogs, may result.
IMPORTANT SAFETY INFORMATION: Not for use in humans. Keep this and all drugs out of reach of children. Do not use in other animal species as severe adverse reactions, including fatalities in dogs, may result.
Merial is a world-leading, innovation-driven animal health company, providing a comprehensive range of products to enhance the health and well-being of a wide range of animals. Merial employs 6,100 people and operates in more than 150 countries worldwide with over €2 billion of sales in 2014.
Merial is a Sanofi company.
For more information, please see www.merial.com.
®MERIAL and ZIMECTERIN are registered trademarks of Merial. ©2015 Merial, Inc., Duluth, GA. All rights reserved. EQUIZIM1504 (06/14)
1AAEP Parasite Control Guidelines 2013, Accessed June 1, 2015. http://www.aaep.org/custdocs/ParasiteControlGuidelinesFinal.pdf
2Kaplan RM. Prevalence of anthelmintic-resistant cyathostomes on horse farms. J Am Vet Med Assoc. 2004;225(6)903-910.
3ZIMECTERIN Gold product label.
4Kaplan RM., Nielsen, MK. An evidence-based approach to equine parasite control: It ain’t the 60s anymore. Equine Vet Educ. 2010;22,306-316.
At Horsemen’s Laboratory we often receive requests from clients for a routine deworming schedule. The new worm control program (targeted worm control) for horses involves performing fecal egg counts to determine when horses, as well as which horses, need to be dewormed. Worm control involves much more than just giving a different dewormer every 6 to 8 weeks.
I have seen many changes in worm control since I graduated from veterinary college in 1970. At that time most horses were dewormed with a combination of Piperazine, Phenothiazine and Carbon Disulfate for bots; the Bendizoles were just coming on the market. They mostly were administered by a veterinarian with a stomach tube because they tasted terrible. Then Ivermectin came along, it was an injectable dewormer that claimed to rid horses of worms forever. Shortly thereafter Ivermectin started selling it as a paste dewormer. Originally deworming was recommended in the spring and fall, 45 days after the first hard frost or freeze. Fall worming was intended to get the bot larvae before they left the stomach to disrupt their life cycle. Then it was thought that deworming 4 times a year was even better. Eventually it was widely believed that every 6 to 8 weeks might even be better. Here in North America it was thought that a daily dewormer might be best of all. Unfortunately, as with most good things there is generally a down side to them and the development of resistance to the dewormers soon became evident.
So what might be causing this resistance to develop? In studies it has become evident; just as in other areas of medicine such as antibiotics and bacterial resistance, it was largely due to the over use of the dewormers. It appears that there was a small portion of the worm population, especially strongyles that were resistant to the deworming medication. The theory is that each exposure of the worm population to a dewormer killed off the sensitive worms, but allowed the resistant ones to reproduce and flourish allowing them eventually to become the majority of the worm population on some farms and in some pastures according to research data collected by Dr. Kaplan at the University of Georgia.
So what can we do to slow the development of resistance to deworming medications? It appears that only deworming when needed will reduce the number of times the worm population is exposed to deworming medication. This will stop killing off all the sensitive worms and allow them to mate with the resistant ones so that a high percentage of their off spring will be sensitive. The only way of knowing when to deworm and which horses to deworm is by doing fecal egg counts. The results of fecal egg counts can tell you which horses are passing the highest number of eggs in a pasture and allows you to target those horses. We may also use a before and after deworming comparison of fecal egg count results to determine the effectiveness of the deworming medication and the possibility resistance has developed to the dewormer used.
Fecal egg counts are not intended to replace deworming, but should be a guide to indicated when to deworm. Fecal egg counts will also indicate which horses are contaminating pastures and their environment and should be dewormed. This will also give horse owners the information needed to classify each horse as a low, medium, or high shedder of strongyle eggs and then they can target the horses’ deworming program accordingly.
Horsemen’s Laboratory is joining forces with the Mahomet American
Legion Auxiliary to help our Veterans!
Each year the American Legion Auxiliary holds a raffle to raise money to assist Veterans in our community. This year they are raffling off a SAMSUNG GALAXY TAB PRO 8.4 - Wi-Fi - 16 GB, it comes with Bluetooth and an Adjustable, Smart Protective Case & Folio Keyboard ($400 value).
For every Horsemen’s Laboratory client who orders 10 or more testing kits or who orders 4 or more testing kits AND signs up for our NEW consulting services before August 15th, Horsemen’s Laboratory will purchase a raffle ticket ($10 value) on your behalf and you will be automatically entered to win the SAMSUNG GALAXY TAB PRO 8.4.
There will only be 500 tickets sold for this special raffle so be sure to order your kits soon!
Thank you for supporting our Veterans!
If you've ever wondered how we process your horse's sample once it arrives at Horsemen's Laboratory ...
Over the years countless clients have asked what I think of daily deworming medications, this is one of the many reasons I started Horsemen’s Laboratory. I began performing fecal egg counts on horses in my practice in Southern California before I dewormed them. I found that less than 5% of those horses were shedding any eggs to indicate they were infected with worms, yet owners were convinced their horses needed to be dewormed. When daily deworming medications became available clients started requesting them, but due to my findings I did not believe in administering daily dewormers. There is some indication that daily dewormers may be responsible for the resistance we see in strongyles to Pyrantel tartrate.
Below is an excerpt from The Handbook of EQUINE PARASITE CONTROL by Dr. Craig R. Reinemeyer and Dr. Martin K. Nielsen that supports this.
Continuous Daily Treatment
This approach involves the daily administration of Pyrantel tartrate to selected horses, either perennially or throughout the grazing season. Daily administration of a dewormer should kill ingested infective larvae (L3) before they invade mucosal tissues, and would have therapeutic activity against recently emerged adults. Consequently, egg counts of horses receiving daily Pyrantel tartrate should remain low while receiving the regimen. Due to national differences in drug approvals and marketing strategies, daily Pyrantel tatrate formulations are only available in North America. Pyrantel pamoate / embonate resistance is much more prevalent in North America than anywhere else in the world: so it has been hypothesized that this may comprise cross-resistance, which was fostered by daily use of Pyrantel tartrate (Kaplan & Nielsen).
Due to the above statement and the fact that Horsemen’s Laboratory has found that many horses on the Pyrantel tartrate daily dewormer have positive fecal counts for strongyle eggs, I cannot recommend its use. If a horse owner decides to use a daily dewormer I would recommend to limit the time it is administered and the horse should be monitored closely by performing fecal egg counts to see if there is resistance or if a resistance is developing.
In March, Horsemen’s Laboratory sold more testing kits and received and processed more samples than in any other month since we opened in 1990! This is mostly due to our loyal clients spreading the word about equine intestinal parasites developing resistance to dewormers. More and more horse owners are being made aware of how they can get involved in the fight against worm resistance by checking their horses before deworming. At Horsemen’s Laboratory most of our new clients come from a referral from one of our loyal clients sharing their experience with other horse owners and we really do appreciate this “word-of-mouth” advertising, thank you!
The biggest contributing factor to the development of resistance to dewormers in worms is the number of times a population of worms is exposed to a dewormer. Each time a population of worms is exposed, the most sensitive worms are killed off while the most resistant worms are allowed to mate and flourish thereby increasing the number of resistant worms in the population. By performing fecal egg counts to determine which horses need deworming, we can greatly reduce the number of times a population of worms is exposed to dewormers.
It has been established that 20% of the horses in a herd are responsible for 80% of the contamination of the pasture with eggs and infective larvae. Therefore, only a few horses in a pasture need to be dewormed, the remaining sensitive worms then mate with the resistant ones and produce offspring that are still sensitive to the deworming medication. This is why daily dewormers are believed to be a big part of the resistant development in worms and should only be used in special situations.
I encourage horse owners to do their own research and read articles on horse health websites about the problem of worm resistance in horses and share what you learn with other horse owners. Develop a plan for testing with your veterinarian, another laboratory or with Horsemen’s Laboratory in order to determine if your horse is a low, medium, or high shedder. Then a proper worm control program can be established according to the category your horse falls into and therefore reducing the number of times your horse and its worm population is exposed to deworming medication.
If you’ve never ordered a testing kit from Horsemen’s Laboratory and were wondering how it works, Dr. Byrd explains the unique service he provides that makes it convenient and affordable for horse owners to evaluate their horses’ worm control program.
Horsemen’s Laboratory sells our test kits online, providing clients with everything they need to ship fecal samples directly to our lab for testing, once we receive the sample it is processed immediately and results are emailed back to the client. This is the most efficient way to have fecal egg count testing done on your horse. Our kit contains everything you need to collect the sample and send it back to our lab including a postage-paid envelope. The price of the kit covers postage, processing of sample and the emailed results.
You can order kits online at www.horsemenslab.com or by calling (800) 544-0599. Online we accept credit cards and PayPal and over the phone we accept Master Card and Visa or you can even mail us a check. Once payment is received Horsemen’s Laboratory will mail out your kits. If you only have 1 horse you can still take advantage of our best price by ordering multiple kits. We will automatically send you 1 kit and hold the others to be sent out as needed. Customers usually receive their kits within 3 – 5 days.
When you receive your kit, you will notice that it contains a small re-sealable plastic bag that has an area for you to print your contact information as well as information about your horse; please fill this out completely as it helps the lab in processing the sample. The envelope provided to mail the sample back to Horsemen’s Laboratory also contains a card that needs to be filled out completely. Many clients find it easier to stick a return address label on the card and plastic bag; some even have labels with the horse’s information to make it even more convenient.
You will also find a small plastic container, this is for the stool sample, be sure to fill the entire container and pack it firmly. Filling the container properly is very important to get the best results; it insures the laboratory has plenty of stool to test and an accurate count is achieved. Packing it firmly eliminates most of the oxygen that preserves the eggs in the sample. Oxygen is essential for the development of the larvae in the eggs. Limiting the amount of oxygen the eggs are exposed to preserves the eggs so they are more readily available when they arrive at the lab for counting. If the sample is not firmly packed often the eggs may hatch, once they hatch we can still count the larvae but the larvae deteriorates faster than the eggs. For best results mail the sample the day it is collected, most samples arrive at the laboratory within 3 - 5 days, occasionally a sample may take longer so it is really important to pack the stool firmly. Horsemen’s Laboratory will immediately process the sample and email the test results to you.
Horsemen’s Laboratory recommends horses that are positive for 200 or more strongyle eggs/gm or any other worms eggs, be dewormed and re-tested to check that the adult worms were killed off and egg production has stopped. In this case, we would mail out one of your remaining pre-paid kits automatically for the re-test. For horses that are listed as negative (no worm eggs found on counting chamber) a pre-paid kit would be sent out in 3 months. If you only purchase one kit at a time, an email will be sent to notify you that your horse is due to be rechecked and you should purchase more kits.
Hopefully this helps you better understand the process, if you have any additional questions please feel free to call (800) 544-0599 or email Dr. Byrd at firstname.lastname@example.org.
907 Westbrook Drive, Mahomet, IL 61853