Montana Equine Medical & Surgical Center June, 2012 Greetings! Welcome to the second issue of our on-line newsletter!
Let us know what you think of this format. As before, there are email-exclusive vouchers at the bottom of this newsletter, so scroll down for more.
In this issue, you'll find Dr. Tamara Parrott's discussion about getting your problem mares bred. Contact us or your local vet to discuss diagnostics and treatments for your mare...its NOT too late to get it figured-out, even if only to prepare for successful earlier season breeding in 2013. Tami has experience in all aspects of veterinary medicine, and sees routine and specialty cases at the clinic in Logan and elsewhere in our community. You can call (406-285-0123) to schedule an appointment with Dr. Tami Parrott, or contact her directly at tparrott@montanaequine.com.
You'll also find a discussion of the use of steroids (cortisone-type medications) in equine performance medicine in this issue. While sometimes considered controversial, there is a very important place for "corticosteroids" in equine medicine, surgery, and performance. Especially in the midst of increasing regulation of performance-enhancing medications and the health of high-impact athletes, we welcome your feedback on this important topic.
We are also very happy to welcome the latest doctor to enter the 12-month internship in medicine and surgery, Dr. Ashley Culp. Ashley hails from Omak, Washington, and graduated from WSU Pullman in 2012. Like all of our interns, Ashley is already a full-fledged veterinarian, and is pursuing advanced training with us this year. Please help us to welcome Ashley to Montana!
As hospital director and head of internal medicine at Montana Equine, it has been fun to edit the first couple issues of our on-line newsletter. In the future, we will welcome other editors from the team at Montana Equine, as well as contributions from "visiting" guest editors. These experts will discuss topics ranging from pasture management to farriery to equine performance and basic husbandry. Please let us know what topics you'd like to see covered! :-)
We look forward to seeing you, and especially to seeing your critters!
Peter Heidmann DVM MPH Diplomate, American College of Veterinary Internal Medicine |
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What are Steroids? The good, the bad, and the ugly...
When veterinarians (or medical doctors, or others) mention "steroids", it is important to remember that there are two different compounds with totally different effects. On the one hand, there are anabolic steroids, mostly including medications that mimic testosterone.
This is the chemical structure of testosterone, the important naturally-occurring anabolic steroid. The carbon ring structure is known in chemistry as a "steroid".
In equine medicine two of the most common anabolic steroids carry the name brands "Winstrol" or "Equipoise". (See more about Stanazolol). These medications increase metabolism, intensity, and improved muscle mass. They are permitted in some equine disciplines and not in others. As testosterone-type medications, large doses of these meds can make geldings or even mares act like a stud. In horses, testosterone is made in the testes of intact males, or rarely, produced abnormally in a mare with ovarian tumors. You can remember that the name "testosterone" comes from the fact that it is produced in high quantities in the testes. Along with many specially-designed boutique anabolics, this is also the kind of medication that are too often abused by human athletes, for example the BALCO Scandal in the so-called steroid-era of Major League Baseball in the 2000s. (See more about BALCO)
On the other hand, consider the slight differences in the structure of the commonly-used and prototypical corticosteroid medications Cortisone and Prednisone below.
This class of medication is called a corticosteroid. Note how there are a handful of slight changes in the microscopic chemical structures of the two molecules. A few simple substitutions cause this molecule to interact completely differently with animal (and human!) tissues. Corticosteroids are produced in the cortex of the adrenal gland; this natural hormone increases during periods of stress, serving to temporarily increase the body's ability to survive. Cortisol and cortisone are naturally-produced; Edward Kendall won the Nobel Prize in chemistry in 1950 for purifying cortisone and paving the way for very powerful, yet relatively inexpensive medical therapies. All drugs in this class profoundly suppress inflammation, which is why they are used in performance horse medicine. In the natural state, for example, during periods when feed is scarce, cortisol can help to increase the body's blood sugar, providing able energy for the short-term necessity of travelling to new food. Or, following a difficult foaling, the mare's natural cortisol would increase, minimizing pain and decreasing inflammation to allow her to get her foal moved to a safe place. Somewhere the sabre-tooth can't catch them.
So these cortisone-type medications are the ones that are utilized so frequently used in equine performance work. Oftentimes, we will just refer to the drugs as "cortisone", or "cortisone-like", because the word "steroid" conjures thoughts of Barry Bonds and Sammy Sosa. Regardless, there are a number of oral and injectable medications in the corticosteroid family, each of which has varying effects on the body.
When it comes to joint injections, there are some corticosteroid medications that have been shown to be "chondroprotective", i.e. protective of cartilage. These medications are generally shorter-acting, and when used judiciously, can minimize the damage that the athlete's body experiences. During periods of inflammation, such as following repeat strenuous exercise, the body releases many types of hormonal messages, many of which can cause pain, swelling and even cartilage damage. Some of these subcellular messengers (such as Interleukin-1), recruit more and more inflammation; this cycle of self-perpetuating inflammation is often considered the body's "over-exuberant" immune response. So there are situations where we have to reach for corticosteroid medications to break the cycle of inflammation. In this situation, treatment with corticosteroid medications can actually improve cartilage health. Its just with over-frequent administration into a horse's joint, even the "chondroprotective" corticosteroid medications can cause thinning of the cartilage. Similarly, corticosteroid medications given orally or by IV or IM injection can be very beneficial in certain circumstances, but the effect of long-term immune suppression can invite poor healing, or infection, or even laminitis.
Please feel free to discuss the use of anabolic steroids and cortisone-type steroids further with us. Like so many things in medicine (and in life!), there is much potential benefit but also some risk associated with utilizing these tools. However, experienced and judicious use of these tools can have many beneficial effects with an excellent margin of safety.
Dr. Peter Heidmann DVM MPH Diplomate, American College of Veterinary Internal Medicine
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Performance Exams
Spring is also time for evaluating your horse's fitness, and making sure any lameness conditions are diagnosed and well-managed.
Here at Montana Equine, we have all the tools and technology to diagnose routine and complicated lameness problems. As always, we will help you arrive at a diagnosis, and provide you with an array of treatment options to maximize your horse's potential.
Call us today to discuss the full range of diagnostic and therapeutic options available to you here at Montana Equine.
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Breeding
Problem Mares
Are you thinking about breeding your mare this spring? Have you tried to have your mare bred in the past, but with no luck? Consider having a breeding soundness exam performed on your mare.
A "problem mare" is a mare that has not become pregnant in a breeding season or one that loses a confirmed pregnancy. It is obviously very important to make sure that there is a suitable environment for the embryo to attach and develop. Having a veterinarian involved in the reproductive care of your mare allows for diagnosis of the problem, treatment if necessary, and the development of a future breeding plan for your mare. It turns-out that the "suitability" of the environment depends on both the absence of infection, and the health of the uterine lining. These aspects are pretty well understood, and problems can be diagnosed and treated via some relatively straight-forward steps in conjunction with your veterinarian. To help explain this further, here are some specific steps you should consider with your mare which will help to give you the best chance of a pregnancy in your mare by ensuring the healthiest uterine environment.
UTERINE CYTOLOGY AND CULTURE: Before breeding your mare, it is important to make sure that a healthy environment exists within the uterus.
To perform a uterine cytology, a sterile sample of uterine fluid is analyzed under the microscope. The cells present in the fluid help determine if there is "active" inflammation within the lumen of the uterus. "Active" inflammation within the uterus would be marked by the presence of inflammatory cells called neutrophils. A uterine cytology gives us an indication of whether there is possible infection within the uterus, which can then be confirmed with a culture.
Uterine culture involves taking a sterile sample of the uterine environment and sending it to the laboratory. At the laboratory, this sample is placed in an incubator with a growth media and watched for any signs of bacterial growth. If bacteria grow from this fluid sample and the cytology indicates active inflammation, your mare should be treated with appropriate antibiotic lavages of her uterus before you try to have her bred. An infection within the uterus will significantly decrease pregnancy rates. The most commonly grown bacteria in the uterus is β-hemolytic Streptococcus, while Klebsiella sp., Pseudomonas sp., Proteus sp., are also common culprits.
Normal uterine cells Normal uterine cells with
(non-inflammatory) inflammatory cells present
(Arrows indicate neutrophils)
UTERINE BIOPSY: Especially in cases of The walls of the mare's uterus should be examined via biopsy to make sure that the uterine wall will allow for proper attachment of the embryo around day 35 of pregnancy. This is especially true in "problem" mares (i.e., those that have a history of pregnancy loss or remaining open after a breeding season). A uterine tissue sample can be obtained vaginally with very little discomfort to the mare. This sample is then sent to the laboratory where board certified pathologists look at the tissue under a microscope. The uterine tissue sample is then issued a "grade" based on the severity of inflammation and scarring present in the tissue sample:
Grade
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Amount of uterine
Inflammation/scarring
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% likelihood of maintaining
pregnancy to term
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I
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Normal uterine lining
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Greater than 80%
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IIA
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Mild to moderate inflammation, scattered scarring of uterine lining
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50-80%
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IIB
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Moderate inflammation with more diffuse scarring of uterine lining
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10-50%
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III
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Severe inflammation/scarring of the uterine lining
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Less than 10%
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So, what if my mare's uterus is a Grade III uterus? Is her career as a broodmare over?
Not necessarily. If your mare has a Grade III uterus, consider embryo transfer as an option (with the exception of thoroughbred mares whose foals are to be registered with the Jockey Club).
EMBRYO TRANSFER: Embryo transfer is a reproductive procedure in which an embryo is flushed from the uterus of a donor mare and is transferred into the uterus of a recipient mare who will then carry the foal to term. Embryo transfer is a procedure that can be performed when:
- A mare cannot physically carry her foal to term or it would be too stressful on her to do so (Grade III uterus, cervical scarring and/or tearing, lameness, elderly mare that is still fertile but would be too hard to keep conditioned throughout pregnancy, etc )
- The mare is a performance athlete and carrying her own foal would hinder her athletic career
- When an owner desires to have more than one foal from a prized mare in a single breeding season.
Embryo transfer is an assisted reproductive technique that requires veterinary skill not only to coordinate the breeding of your mare and flush the embryo, but also to follow the reproductive cycle of a recipient mare and chemically alter this cycle to synchronize it with your mare. The embryo, when it is 7-8 days old, is carefully flushed out of the uterus and placed into the uterus of a surrogate mare (whose reproductive cycle has been synchronized with your mare's cycle). A younger embryo would still be in the oviduct and not yet in the uterus, and an older embryo, greater than age 9 days, would be too large and fragile and thus have a higher risk of damage during transfer. A day 8 embryo is actually visible to the naked eye, and looks like this:
To flush the embryo, a sterile catheter is placed into the donor mare's uterus via the cervix and the uterus is filled with fluid. The fluid is then allowed to flow back out of the uterus and through a filter that will "separate" the embryo from the fluid. The filter is then rinsed and the embryo is caught in a collection cup. Once the embryo has been located in the collection cup, it is carefully placed via the cervix into the uterus of the donor mare. Embryo recovery rates are approximately 50-70% from reproductively healthy mares.
REPRODUCTIVE CONFORMATION EXAM:
If you have your mare bred and desire to have her carry the foal, she is scanned via ultrasound for pregnancy on day 14-16. If she is indeed pregnant, her perineal conformation is evaluated. If she is determined to have a "tipped" conformation, the mare is more susceptible to ascending infection of the placenta (placentitis) from fecal (bacterial) contamination. The placenta is a temporary organ that forms and helps to support the foal while in the uterus. Placentitis is inflammation in the placenta that causes it to separate, decreasing blood supply to the fetus (and thus oxygen and nutrition!). A majority of cases of placentitis in the mare are the result of an ascending infection. Thus, in order to help decrease the chance of the mare developing an ascending infection, a caslick's can be placed. Placing a caslick's is a procedure where the edges of the upper 2/3 of the mare's vulva is sutured together to prevent ascending contamination of the placenta and the lower 1/3 is left open so that she can still easily urinate. It is important that the caslick be surgically re-opened about one month prior to foaling so that the mare does not traumatically tear during the process of foaling.
Normal Vulvar Conformation Abnormal "Tipped" Vulvar Conformation
If you would like further information about breeding services offered at Montana Equine, you can visit our website Reproductive Services) or call the clinic (406-285-0123). We would be happy to answer any of your questions!
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Did you know? Some updates on our veterinary team here at Montana Equine:
Dr. Tami Parrott: Having completed a full-year of post-graduate training in equine medicine and surgery with us here at Montana Equine, we are excited to announce that Dr. Parrott is remaining on the team as an associate veterinarian. Read more about Dr. Parrott on the Montana Equine website here. Dr . Ashley Culp
Montana Equine is also happy to welcome Dr. Ashley Culp, our latest intern in the one-year internship training program. Dr. Culp, who hails from Omak, WA, grew up with AQHA horses, graduated from WSU Pullman in May, 2012. The number of veterinarians who seek more-specialized training after veterinary school is on the rise, but still less than half of all vet school graduates seek internship training. Please help us welcome Dr. Culp to the team. You can read more about Dr. Culp on the Montana Equine website, here |
Dr. Al Flint Dr. Flint is our full-time surgery resident, and is midway through his ongoing surgery residency training. Specialized training in equine surgery is very demanding, and will put Dr. Flint into an elite class of very few surgery specialists practicing full-time in our region. Al also has advanced credentials and expertise in reproductive medicine, and handles most of the reproductive care that is offered at Montana Equine. If you have questions or comments for Dr. Flint, you can contact him You can call (406-285-0123) to schedule an appointment with Dr. Flint, or contact him directly at aflint@montanaequine.com. You can see more about Dr. Flint on the Montana Equine website, here. Dr. Peter Heidmann Dr. Heidmann is the owner and hospital director of Montana Equine. He is the only board-certified expert in equine internal medicine currently practicing in Montana or Wyoming. In addition to his core of performance medicine, he sees speciality cases in ophthalmoloy, neonatology, neurology, cardiothoracic diseases and abdominal conditions. You can see more about Dr. Heidmann on the Montana Equine website, here |
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In this Issue:
Breeding Problems and Solutions
What is a Steroid?
Updates on our Team
Have you seen our on-line pharmacy?
Now, you can request refills and new prescriptions and have them delivery to your house. Hassle Free!
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Ever!!
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