Mare Breeding: A Guide for Horse Owners

Mare Breeding: A Guide for Horse Owners

Whinny’s Wisdoms

Springhill Equine Veterinary Clinic

Spring is in the air, the birds and the bees are out, and foals are hitting the ground. Everyone seems to be thinking about making more of them! Don’t we have enough horses in the world? I think we need more mice. But seriously, breeding your horse is a significant decision that requires careful consideration. In the United States, we’re facing an overpopulation of horses, and adding more to the population should be a thoughtful choice. While the idea of passing down desirable traits, like behavior, movement, personality, or talent, can be appealing, it’s crucial to know that these traits aren’t always inherited by offspring. Each horse is unique, and what makes a great performer or companion doesn’t always transfer to the next generation.

Moreover, breeding a mare especially demands foresight and planning for the foal’s future. It’s essential to have a well-thought-out plan for the foal once it arrives, including a budget set aside for potential health issues in its early days to weeks of life. Consider that if a foal can’t be sold due to genetic issues or a lack of desired talents, the responsibility for its care falls on the mare owner for the rest of its life. This responsibility extends far beyond the cute foal stage into adulthood, which involves time, finances, and dedication. Making the decision to breed should involve serious consideration of the long-term commitment to the foal’s well-being, ensuring a stable and secure future for both the mare and her offspring. And if you’re looking to make a profit from breeding horses, just cut your losses now! I can’t even tell you how many financial horror stories I’ve overheard at the clinic from owners losing money on breeding.

Whinny’s Wisdom: MOST people who breed horses do not turn a profit from it. Don’t count on ANY foal to be a financial windfall!

Understanding Mare Reproductive Health

Reproductive services for mares should involve comprehensive examinations, utilizing diagnostic tools like ultrasound and hormonal assays, and scheduled follow up exams. This helps identify any potential issues that could hinder fertility, such as uterine infections, hormonal imbalances, or structural abnormalities.

Various health problems, from infections to systemic conditions, can affect a mare’s fertility. Addressing these concerns early is crucial. Treatment options may include antibiotics, hormonal therapies, or management adjustments to enhance overall reproductive success. It’s also very important to consider if it is worth pursuing breeding in a mare with any of these reproductive conditions. Basically, do you want to breed A horse, or do you want to breed THIS horse?

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It pays to be prepared! Before any birds or bees are brought together, there are some important steps. First of all, is your mare fit and healthy enough to be bred? Let’s go over what information we need to figure that out:

Vaccination Status: All horses should be vaccinated regularly by the veterinarian you have a great relationship with, but it’s even more important for a broodmare whose immune system will be challenged by growing a brand-new creature for 11 months. Our docs require mares to be up-to-date on vaccinations for diseases like Eastern and Western Encephalitis, Tetanus, West Nile, Equine Influenza, Equine Herpes, and Rabies. Go check out some of Tony’s old blogs to learn about these vaccines if you’re curious!

Dental and Hoof Health: Regular farrier visits and dental care are vital for maintaining a mare’s health during pregnancy. Would you want to carry an extra 100 lbs in your abdomen if you already had bad feet or a toothache?

Reproductive History: Knowing if your mare has previously foaled or been bred helps us understand potential complications or issues that might arise during the breeding process. Any previous reproductive diagnoses, such as uterine infections or cysts, are critical to know about and potentially manage prior to insemination. A mare that has had a difficult pregnancy previously won’t necessarily repeat that, but she may. Similarly, a mare that’s had very easy pregnancies in her past could always have a difficult time this go around. It’s important to be emotionally and financially prepared for above-and-beyond care if your mare has a difficult pregnancy. This can involve frequent exams, medications, or even hospitalizations. If your horse has not ever been pregnant before, this can also sometimes present challenges, especially if she is older than 8-10 years of age.

The prebreeding reproductive evaluation is a pivotal step in ensuring a successful breeding outcome. Through the use of diagnostic tools like ultrasound, uterine culture, and cytology, our doctors comprehensively assess the mare’s reproductive health. Ultrasound examinations offer valuable insights into the reproductive tract, detecting structural abnormalities, cysts, or inflammatory changes that might hinder fertility. Uterine cultures identify bacterial infections within the uterus, enabling targeted antibiotic treatments to resolve underlying issues. Concurrently, uterine cytology evaluates the cellular composition of the uterine lining, pinpointing inflammation or irregularities that could affect the mare’s ability to conceive or carry a pregnancy to term. This comprehensive evaluation empowers veterinarians to proactively address potential issues, optimizing the mare’s reproductive health and significantly increasing the chances of a successful breeding experience.

Turn the Lights On

For early breeding (before March/April), implementing a Light Protocol helps regulate the mare’s estrous cycle. This involves simulating longer daylight hours to prompt hormonal changes, preparing the mare’s reproductive system for an earlier breeding season. This process typically begins around 60-90 days before the desired start of the breeding season, usually in late fall or early winter.

How to Implement a Light Protocol:

  1. 1. Light Duration and Intensity: Mares are sensitive to light changes. Mimicking longer daylight hours tricks their bodies into believing spring is approaching, stimulating hormonal changes. Provide artificial lighting in the mare’s stall, ensuring 16 hours of continuous light daily. Natural and artificial light combined should meet this duration.
  1. Light Timing: Start the Light Protocol in late fall or early winter. Calculate backward from the desired breeding date, allowing 60-90 days of light stimulation before the intended breeding season begins.
  1. Light Management: Ensure consistent lighting without interruption. Use 100-200-watt LED, incandescent or fluorescent bulbs placed approximately eight feet above the mare. The lighting should be evenly distributed throughout the barn, including the stall where the mare resides.
  1. Light Control: Use automatic timers to maintain a regular schedule. Artificial light should start early in the morning, simulating dawn, and continue until late in the evening, mimicking dusk. Avoid sudden changes in light intensity or duration.

Implementing the Light Protocol at the right time is critical. For early breeding, starting the protocol around late November to early December allows for the required 60-90 days of light exposure before the breeding season, typically beginning in February or March. Regular monitoring during the Light Protocol ensures proper response. Veterinary guidance and monitoring hormone levels may be necessary to confirm the mare’s readiness for breeding after the completion of the light exposure period.


As they say, timing is everything. Once our team has determined your favorite mare is all ready for a bun in the oven, the work has only just begun. Horses have a 21-day estrous cycle, but the period of fertility (estrus) varies from 2-8 days across each cycle, with the length of diestrus (uterine inactivity) adjusting to keep the cycle at about 21 days. Because of this variability, it is crucial your mare have ultrasound assisted reproductive exams OFTEN. When I say often, I mean sometimes multiple times per day. The margin for error in timing depends on how you are planning to have your mare bred.

In general, we have the most flexibility if the mare will be live covered and the least flexibility if she will be artificially inseminated using frozen semen. This usually means you are either boarding your mare at our clinic (yay, more friends for me!) or trailering her in every 1-3 days until she is bred. After the deed is done, we have to confirm she has done her part and released an egg. This is also done with ultrasound. Then, there’s more to schedule!

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Fourteen days after confirmed ovulation will be the first pregnancy check. That 14-day mark is super important, because we have to look for twins. Horses are super particular with their insides (see all of our colic blogs!) and their insides can absolutely not handle two babies at once. So, if we find twins, we have to “pinch” one of the embryos in order to save the other embryo and the mother. But we can only do this very early in her pregnancy.

After that fourteen-day check when she is confirmed pregnant, one of the nice technicians at the clinic will email you a Pregnant Mare Schedule which details the next 11 months of her and your life. She’ll be visiting us at least every few months for ultrasound exams and vaccines until her baby is born. And if you feel anything is going wrong in between those frequent visits, she will visit us then too!

Conclusion: Breed Responsibly

While the thrill of breeding your mare is enticing, responsible breeding involves thorough consideration and preparation. Each mare is unique, and individualized care to whole horse health is vital for successful reproduction. At Springhill Equine, our docs prioritize individualized care and thorough assessment to maximize the chances of a successful breeding outcome. Our aim is not just conception but ensuring the health and well-being of both mare and foal.

I think I gave a pretty thorough lecture today, but if you would like any further information or to schedule your mare’s reproductive evaluation, you can speak to our lovely office staff by calling 352-472-1620.

Until next week,


P.S. If you really want to get intense with breeding knowledge, my docs have several seminars on the topic over on our YouTube Channel. They are way more in-depth than my blog, and completely free! You can find all of our Seminars by Clicking Here.

Whinny’s Wisdoms is the official blog of Whinny the Clinic Mouse at Springhill Equine Veterinary Clinic in Newberry, Florida. If you liked this blog, please subscribe below, and share it with your friends on social media! For more information, please call us at (352) 472-1620, visit our website at, or follow us on Facebook!

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Mare Reproduction Process

Mare Reproduction Process

Whinny’s Wisdoms

Springhill Equine Veterinary Clinic

Hey everybody, Whinny here! It’s almost December, so it’s time to start thinking about breeding mares. The best plan is to avoid breeding altogether and buy a horse that’s grown up, trained, and ready to go. But for those of you who like to do things the hard, painful, expensive way (with no guaranteed outcome!), let’s get into the weeds.

The cycle of reproduction in mares is a complex process, but having an understanding of this process allows us to manipulate a mare’s reproductive cycle to increase our chances for successful breeding. In this post, we will explore the key stages of mare reproduction.

Stage 1: Estrous Cycle

The estrous cycle, also known as the “heat” cycle, is a crucial stage in mare reproduction. Unlike mice and humans, horses are seasonal breeders, and their estrous cycle is dependent on the length of daylight. Typically, the cycle occurs during the spring and summer months when the days are longer.

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The estrous cycle lasts approximately 21 days, during which mares experience various behavioral and physical changes. These changes are regulated by hormonal fluctuations. As a mare enters her heat cycle, she may become more receptive to a stallion’s advances, displaying signs such as frequent urination, vocalizations, and a more relaxed stance of the tail.

Paws! Stage 1.5: Anestrous and Transitional Mares

In contrast to the estrous cycle, mares also go through periods of reproductive inactivity called anestrous. Anestrous is the phase when mares experience a temporary cessation of their estrous cycles and show no signs of heat. This usually occurs during the colder months of the year, particularly in late fall and winter when daylight hours decrease. The reduced exposure to daylight triggers hormonal changes that suppress the estrous cycle, allowing mares to conserve energy and prepare for the challenges of winter.

Additionally, mares undergo a transitional phase before entering full anestrous or during the transition from anestrous to the onset of the breeding season. This period is known as the transitional phase, or transitional estrous. During this time, mares may exhibit irregular heat cycles and display mixed behavioral and physical characteristics of both estrous and anestrous. This can make it difficult to determine the mare’s actual reproductive status and is one of the greatest challenges when breeding mares.

Stage 2: Ovulation

During the estrous cycle, the mare releases an egg from her ovaries through a process called ovulation. Ovulation usually occurs around the end of the estrous phase, approximately 24 to 48 hours before the cycle ends. If a successful mating occurs during this window, there is a higher chance of conception.

Stage 3: Fertilization

Fertilization is the process of the mare’s egg being successfully fertilized by the stallion’s sperm. The sperm can survive within the mare’s reproductive tract for several days, increasing the likelihood of fertilization if mating happens close to ovulation.

Stage 4: Pregnancy

Pregnancy is confirmed with an ultrasound at 14 days after ovulation. Horse gestation lasts approximately 11 months, although it can vary slightly depending on individual factors. During this time, the developing embryo implants itself in the mare’s uterus, where it receives nourishment and protection throughout the gestation period.

Stage 5: Parturition (Foaling)

Parturition, or foaling, in a mare unfolds in distinct stages, each essential for a successful and healthy delivery. The first stage is marked by behavioral changes, such as restlessness, pawing, and repeated lying down and getting up. This is accompanied by the relaxation of the muscles in the mare’s hindquarters.

The second stage involves the actual birthing process, where the foal is expelled from the uterus. The mare may lie down and get up repeatedly, and the amniotic sac containing the foal usually ruptures. The foal’s front feet and nose appear first, followed by its shoulders and body. The mare actively participates in this process by contracting her abdominal muscles.

The third stage involves the expulsion of the placenta, which is critical for the mare’s health. This process usually occurs within a few hours after foaling. Monitoring and assistance during these stages are crucial to ensure the well-being of both the mare and the newborn foal.

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The Rest of the Story

These five stages are what happens when everything goes right. As you may know, if you’ve been a horse person for more than a few weeks, it’s unlikely that everything is going to go right with breeding. There are a variety of problems that can happen at every stage of pregnancy, and many of them stop the process. And it’s not uncommon for a mare to be bred repeatedly and still not get pregnant (just like people. Mice don’t have that problem).

There are a lot of factors that make a mare a good or bad candidate for breeding. One of the biggest ones is age. I know you humans can get confused about how old your horse is, and how that translates to human years. Let me give you a rule of thumb chart to go by:

Horse  Human (equivalent age)

  3            15
  6            25
  10          35
  15          45
  20          55
  25          65
  30          75
  35          85

Horses are just like people: they are really fertile when they’re young (think 4-7), and once they get past a certain age (think 10), everything becomes high risk and high difficulty (and highly not recommended).

Our team of expert veterinarians can do a lot of things to help you set your mare up for a successful breeding. There are no guarantees in reproduction, but if you do all the things, your odds of success are greatly improved. It’s no different than anything else in life, really. The first step is talking to my docs and making a plan in December so that all the pieces can be put in the right place at the right time. You can do that with a simple call or text to the Clinic at 352-472-1620. And make sure you bring me a little bit of cheese when you come in for your pre-breeding exam!

Until next week,


P.S. If you’re serious about breeding your mare, you’ll want to listen to all the comprehensive breeding episodes of Straight from the Horse Doctor’s Mouth, which is the podcast my docs produce. It’s loaded with great information that you won’t want to miss out on. You can subscribe on Apple Podcasts, Spotify, or anywhere you get your podcasts, or just check them out over on the Podcast Page of my website.

Whinny’s Wisdoms is the official blog of Whinny the Clinic Mouse at Springhill Equine Veterinary Clinic in Newberry, Florida. If you liked this blog, please subscribe below, and share it with your friends on social media! For more information, please call us at (352) 472-1620, visit our website at, or follow us on Facebook!

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Twins: Double Trouble

Twins: Double Trouble

Tuesdays with Tony

This past week has been a busy one at the clinic for me. All my paddocks have been full, and all my stalls occupied. I’m exhausted, but it’s been very rewarding to see all the foals frolicking in the paddocks. We are well into breeding season and have been performing pregnancy check after pregnancy check. These appointments are stressful yet rewarding. As the doctors are scanning the uterus looking for one little black dot, the suspense could be cut with a knife. As a cat, I can feel it as the mare’s owner, the doctors, and the technicians wait, then I hear it: the cheers that mean that a little black dot has been found! It’s heartbreaking when the dot isn’t found. And maybe even worse than not finding the black dot is seeing two black dots.

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Double the dots does not mean double the fun. Two black dots on a pregnancy check means that there are two embryos developing, and two embryos means twins. Unlike many other animals, twins in horses is not a good thing. Fortunately, the development of two embryos is not super common, but when it happens, it’s important to know early on. That’s why my doctors always highly recommend a pregnancy check 14 days after known ovulation. There’s a very narrow window to deal with twins. Between days 14 and 20 of pregnancy is the only time that twins can be managed without major risks. We’ll talk about management of twins while in-utero and what can be done to ensure the birth of a single healthy foal, but first let’s discuss what happens when twins are not managed in-utero.

At your mare’s 14-day pregnancy check, your veterinarian will thoroughly examine your horse’s uterus and ovaries via transrectal ultrasound to find a pregnancy and ensure that only one embryo is found. If two embryos are found, the suggestion will be to “crush” or “pinch” one of the embryos. A mare’s uterus is not capable of carrying two healthy foals to term. The likelihood of a mare having twins that survive to foaling is extremely rare. If a mare does foal out twins, it’s unlikely that one or both of the twins will survive for more than a day or two.

If twins are not detected between 14 and 20 days of pregnancy, aborting the pregnancy becomes one of the options early on. To do this, a medication is administered to the mare which gets rid of the Corpus Luteum. The Corpus Luteum produces progesterone which helps maintain a pregnancy. Once the Corpus Luteum is gone, the embryos won’t be able to survive. After 150 days of pregnancy, the Corpus Luteum no longer holds the pregnancy and endometrial cups take over to provide progesterone and maintain pregnancy. If twins are not detected until after 150 days of pregnancy, aborting one or both of the fetuses becomes extremely difficult and dangerous. Transabdominal procedures are performed to abort a fetus, which puts the other fetus as risk for abortion as well.

Incomplete Ossification of Cuboidal Bones

If a mare carries twins to term and both survive, it’s likely that they won’t be developed completely. Despite being born full-term, when twins are born, they come out as premature foals. One problem that premature foals have is lack of bone development. More specifically, the small bones of the carpus (knee) and hock do not develop before birth in premature foals and in this case, twins. During the development process in-utero, the cuboidal bones in the carpus and hock start off as cartilage and turn into bone in the later stages of development.

When twins are born, their bones usually aren’t developed, and they have a significant amount of cartilage present in these joints. If foals were like human babies and laid around all day, having knees and hocks made of cartilage wouldn’t be an issue because they wouldn’t be holding up 200 pounds on cartilage alone. When the weight of a foal is placed on cartilage, it crushes the cartilage so that when bones develop, they’re misshapen and will develop arthritis before the foal is even a few months old. As you can imagine, this leads to a very painful, difficult life for the foal from day one.

Lung Development

To go along with the prematurity of twins is the lack of lung development at birth. The last thing to develop before a foal is born is their lungs. That’s why we never induce foaling unless we absolutely have to. When twins are born and have premature traits, one of the largest concerns is their lung develop (or lack thereof). When their lungs are not developed appropriately, they can’t get enough oxygen to survive. Without supplemental oxygen they will not thrive, not grow, and will be prone to illness.

Other Developmental Issues

Because twins have to share a placenta that can’t fully support them completely, they are born small and are more prone to developing illnesses. Being small in stature makes nursing difficult and increases the risk of developing aspiration pneumonia. They may require an indwelling feeding tube and being fed every few hours via the tube. The mare may not develop enough colostrum to supply both foals with enough antibodies to supply them with a strong immune system. When a twin does not get enough colostrum, they require treatment with intravenous plasma to ensure they have appropriate antibodies to fight off diseases and illnesses. Twins will require intensive treatment, they often require hospitalization, and they are not easy. Moreover, they are not cheap.

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The moral of the story is, have your brood mares monitored early, monitored frequently, and appropriately cared for should twins be found on 14-day pregnancy ultrasound. While it might seem like you are getting more bang for your buck if twins are found, listen to your veterinarians and their recommendations if twins are found. It is, in fact, a life or death scenario for the foals and the mare.

Until next week,


P.S. If you’ve ever read any of my post scripts, then you know about the Podcast and the YouTube Channel, and you’ve subscribed to both. You’ve also probably already scrolled down and subscribed to my blog. So, really, you’re plugged into all the things, and absorbing horse knowledge in every way that I have to share it. Pat yourself on the head, and give yourself a treat, becaue you are a good human.

Tuesdays with Tony is the official blog of Tony the Clinic Cat at Springhill Equine Veterinary Clinic in Newberry, Florida. If you liked this blog, please subscribe below, and share it with your friends on social media! For more information, please call us at (352) 472-1620, visit our website at, or follow us on Facebook!

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Starvation, Breeding, and Microchips

Starvation, Breeding, and Microchips

Tuesdays with Tony

 How, you ask, are starvation, breeding, and microchips related? What weird cat logic is this? Read on and find out. I’m dropping some serious cat wisdom this week.


Recently Dr. Vurgason and Dr. Lacher had the daunting task of working with a group of 18 incredibly thin horses. Like, body condition score 1 out of 9 for a majority of these horses. Dr. Vurgason worked on one who was in such bad shape he was down for 24 hours because he didn’t have the muscle mass or energy reserves to stand. That’s bad! I hope to only be able to imagine how these horses felt. I’m the one starting to insist on dinner at 4:30 pm when it is never served before 5:30 pm. 

There were abrasions on hips because the skin couldn’t take the pressure of the bony points with absolutely no covering. Remember all that rain recently? Many of these horses have just about no hair thanks to horrible cases of rain rot. When I say this was a sad bunch of horses, I really, really mean it. Luckily they found their way to a great rescue (and, trust me, they aren’t all great). If these horses can handle the introduction of food over the next week or so, they’ll be ok.




The rescue that has this herd pulls a lot of horses from very low level auctions. The kill pen kind of auctions. I asked what breeds they see most often. My guess was going to be thoroughbreds. Yvonne told me my fine feline instincts were wrong. At first I was horrified to be wrong, but then I listened, and learned. Most are Quarter Horses, followed by Standardbreds, and draft breeds. 

Why is it Quarter Horses? Because of the huge breeding operations that exist with little outlet for the ones that “don’t cut it.” Literally don’t cut it, since many of these are breeding for horses that work cows. I beg of you guys out there looking at pretty stallion pictures right now, anxiously awaiting the upcoming breeding season. THINK about whether this is something you really want and need to do. Could you find the horse you’re looking for without having to breed? Is your mare so special that it has to be her? 

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I don’t mean to take away from your horse, I mean to have you think about breeding. There are tons of great horses in backyards starving, and in kill pen auctions. What would it mean to a horse to never have to end up there? How great would it be to check out the foals, weanlings, yearlings, or even two year olds at a great breeding program, and pick out the one that was the color and sex you wanted? Let me tell you, that never happens when you breed your own. Just ask Dr. Lacher, who prefers geldings, and got 4 fillies and 1 sweet but not-talented gelding.




How the heck do microchips end up in this story? Simple. At one time, these horses were likely bred or owned by someone who hoped for the best for them. That’s not how their lives ended up. If those owners had microchipped these horses, they would at least have a way to be contacted. We talk about microchips most frequently when it comes to natural disasters, or downed fence lines, but what if you got a call about a horse you sold 10 years ago? I’m guessing most of you would want to know that horse would have a soft place to land. So microchip your horses. It can do way more than bring them back if they’re wandering lost after a hurricane. 

The unwanted horse is an incredibly complicated problem. They are big, expensive animals. If each and every person in the horse industry took a moment to be sure they were helping, and not contributing to the issue, we could reduce the suffering of horses. I have faith in you humans, even if I don’t usually come across that way.

Now be a good human and subscribe to my weekly drop of cat wisdom. 

Until next week,


P.S. I know I usually remind you about the podcast that the humans do, which is pretty popular. You should definitely check that out. However, this week is a special announcement! The humans, or Dr. Lacher’s husband, in particular, have published a book called Adventures of the Horse Doctor’s Husband. It’s pretty good, and I’m not just saying that because I have a cameo appearance in it. Speaking of rescuing horses in bad situations, remember Highway, the horse that fell out of the moving trailer last winter? You’ll recognize him on the cover, and if you buy the book, you’ll be making a contribution to him. It’s a win-win for everyone. Just click on the banner below to learn more about the book. 

Tuesdays with Tony is the official blog of Tony the Clinic Cat at Springhill Equine Veterinary Clinic in Newberry, Florida. If you liked this blog, please subscribe below, and share it with your friends on social media! For more information, please call us at (352) 472-1620, visit our website at, or follow us on Facebook!

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Should I Breed My Horse?

Should I Breed My Horse?

Tuesdays with Tony

As a cat, one of my many, many tasks is to humble humans daily. With breeding season coming up, I feel it’s my duty to have a heart-to-heart with you about what breeding actually means. I have come to this subject today because our 10th Annual Castration Clinic (where Springhill Equine has a ball… or two) is coming up soon. It’s important when thinking about your horse as a stallion, that good stallions make great geldings! Anyway, moving on to the topic at hand.


Should you?


Got a mare? Got a stallion? Make a baby. Sell the baby. It’ll be great.

Let’s start with the mare. I hear from humans all the time that they have a great horse, and they’re not wrong. However, look at your mare with a critical eye to determine if she should be bred. Sure, she does what you love doing, and she does it well (if she doesn’t, why would you breed her?), but do you want to pass on her conformation? Does she have personality quirks you have come to love, but would never, ever want in a horse you were looking at to buy? For many breeds, you should also have genetic testing done to see if she carries things like PSSM, OLWS, or other potentially life-threatening genes. If she does, you really want to make breeding decisions carefully. Need help deciding if you should breed your mare? Talk to someone you trust in your discipline. [This person should not own a stallion you may breed your mare to.]

For stallions, I have two words: perfect and money. If you’re going to keep your horse a stallion, he should have it all.  He should have the conformation your discipline is looking for, the personality, bloodlines, genetic testing, and a track record. That last part is the beginning of the money. If you don’t have the funds to campaign a stallion so that he can prove his value in your discipline, geld him. And after you campaign him, if you don’t have the funds to promote him, and his offspring, geld him. The sad truth is no one will promote your stallion and his offspring like you do. Don’t expect others to do that for you. This means advertisements, stallion auctions, showing babies, training fees for those babies. All of it. This often means stallions don’t even begin to pay for themselves for 10 to 15 years! All things to think about before leaving those testicles on.




Your mare is amazing, so is your stallion. Let’s make a baby! Whoa, whoa, whoa! I have siblings. Maybe some of you humans have siblings, too. I don’t know about your family, but I’m the only one to turn out decent in my family. I have a job, a blog, a warm lap to sleep on, and minions to deliver me food and beverages. Just because you have genetic potential, doesn’t mean the kid is going to get those good genes. It’s still a roll of the dice. Do you have a plan for those 1D barrel horses you cross, and end up with a something that couldn’t win the 7D if that was a division? A better question is, do you have a plan for getting this foal raised and trained to its potential? This can work out well if you can do all the training, but if you need to send baby off for lots of training, or you do a discipline that takes years to master (I’m talking to you, Dressage), it can add up to a lot of dollars!

Eyes wide open


I’m not saying don’t breed your horse, I’m just reminding you to think about the entire process. I’m also going to ask that you visit a local horse rescue, and talk with them about the horses they have. Someone bred every one of those horses.

And now I’m off to prepare for the Castration Clinic. This year’s motto is Geldings: Ball-less and Flawless!

Until next week,


P.S. I’m sure that by now you’ve subscribed to my blog, so I’ll skip that part. Have you tried out the podcast that the humans do yet? It’s called Straight From the Horse Doctor’s Mouth, and it’s a half hour of amazing, free information about horse stuff that you can listen to while you drive, while you wash your horse, while you jog (you humans and your crazy exercise stuff), or even while you’re pretending to work. Hey, I’m a cat. We’re all about slacking. Don’t judge. You can listen right from our website by clicking the link, or you can download it on Spotify, Stitcher, Castbox, or wherever you get your podcasts.

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Tuesdays with Tony is the official blog of Tony the Clinic Cat at Springhill Equine Veterinary Clinic in Newberry, Florida. If you liked this blog, please subscribe below, and share it with your friends on social media! For more information, please call us at (352) 472-1620, visit our website at, or follow us on Facebook!

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Pregnant Mare Care

Pregnant Mare Care

Tuesdays with Tony

Pregnant Mare Care 

Congratulations! You’ve got a bouncy baby horse coming in about 11 months! In my experience watching the humans around here, it’s a very long 11 months. There are important things to do during that time to make sure the baby arrives happy and healthy. In my experience, humans are really good at getting the heartbeat ultrasound check at 30 days, but not so good at the rest of it. Read on for Tony’s words of equine wisdom regarding pregnant mare care.


These are just so freakin cool! You get to see that baby go from a black dot on the screen at 2 weeks to having a heart beat at 30 days. At the 60 day ultrasound there are legs and something resembling a head! They grow so fast. My Docs are checking way more than just the baby when they’re ultrasounding, though. They are also checking the entire uterus and ovaries to make sure they’re doing what they should.

The most important thing they are checking is where the cervix and placenta meets. This is where the outside world meets the uterus, and it’s where problems often start. My Docs will check to be sure the placenta is tight up against the cervix, along with measurements to be sure it’s not too thick. A thick placenta can be an indication of infection. If infection is spotted early, it can be easily treated with antibiotics. On young mares who don’t have a lot of exposure to other horses, ultrasounds should be done at 5, 7, and 9 months to check for infection. On older mares (over 12 years), problem mares, or mares who see lots of other horses all the time, the Docs recommend ultrasounds at 3, 5, 7, and 9 months.


Rhinopneumonitis vaccines are super, super, super important for pregnant mares. Most humans call this a Pneumobort shot. Rhinopneumonitis is a Herpes virus. Herpes viruses are nasty little buggers. Once a horse has the virus, they’ve got it for life, and most horses are infected in their first year of life. The virus spends most of its time hibernating, but stress (I hear pregnancy is definitely stressful) can make it wake up. Frequent vaccinations keep the immune system on high alert for this virus. This means that if it does wake up, the immune system is right there to tackle it.

Rhinopneumonitis vaccines follow the same rules as ultrasounds. If your mare doesn’t meet new horses often, she can get a vaccine at 5, 7, and 9 months. If she is a social butterfly, she should get vaccinated an additional time at 3 months. This vaccine can be what my Docs call hot (horses often get a mild to moderate vaccine reaction from it). The Docs recommend some Bute beforehand to help reduce the reaction if you’re worried.

At around 10 months of pregnancy, your mare will need all her “regular” vaccines. For most mares this is Eastern and Western Encephalitis, Tetanus, Influenza, West Nile Virus, and Rabies. This makes sure the baby has great protection against these viruses when it gets here.


Don’t. Ha! That was easy. Seriously though, see my numerous blogs on deworming. Watch an entire presentation by my Docs about deworming here: Deworming Seminar  Fecal egg counts and targeted deworming is the way to go. Don’t go deworming all willy nilly like you humans are prone to doing.


Don’t go crazy. Again, easy! Have your mare on a good feed. If she gets skinny easily, then a mare and foal feed may be necessary. If she’s an easy keeper, then good quality hay and a ration balancer may be all she needs. This is not the time to get her fat. It won’t make foaling easier on you or her.


Yes. Of course they tell me that too, but I don’t like exercise, so I don’t. Pregnant mares can go out and do what they did before they were pregnant with a few guidelines in place.

  1. Don’t do more than you did before she was pregnant. If you went for 5 mile trail rides, great. Don’t sign up for the 50 mile endurance ride.
  2. Watch how hot she gets in the early stages of her pregnancy. Being really hot can be really, really bad for embryos younger than 90 days.
  3. Listen to your mare. At some point, later in her gestation, she’s going to tell you she doesn’t want to work anymore. Respect that.

Before you know it, 11 months will have flown by and you will be anxiously awaiting your foal. Spend the time wisely by thinking up perfect baby names, and keeping your mare up to date on all her prenatal care! Bring her into the Clinic for her happy mom check ups and I’ll even throw in a free CAT scan by yours truly.

Now be a good human and subscribe to my blog. Scroll down a tiny, tiny bit. So easy a human can do it.

Springhill Equine Veterinary Clinic

Tuesdays with Tony is the official blog of Tony the Office Cat at Springhill Equine Veterinary Clinic in Newberry, Florida. For more information, please call us at (352) 472-1620, visit our website at, or follow us on Facebook!

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