Equine Reproduction

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 Deciding to breed a mare is a difficult decision, not for the faint-hearted. They say the mare contributes 60% to the foal, so relying solely on an exceptional stallion can only take you so far. It's crucial to be honest and critical about your mare from the start to identify areas for improvement. As a breeder, it's your responsibility to improve the breed with each generation. Assess the mare's conformation, movement, and temperament with candor. Is she truly a mare of breeding quality? She should be evaluated by one of the major registries for their opinion and approval for whether she is an appropriate mare to breed. Inspectors have a wealth of knowledge and can assist with feedback about the mare, her strengths and weaknesses. Is she sound, healthy, and devoid of vices? If she isn't sound, can she manage the physical demands of pregnancy comfortably? If she's unsound, is it attributable to a conformational issue she might pass on, or is it an unrelated accident? We test all our mares for Warmblood Fragile Foal Syndrome (WFFS), and fortunately, they're all negative and non-carriers. However, if a mare is a carrier, it must factor into decisions about stallion selection. A reproductive veterinarian should evaluate her for breeding soundness, conducting tests like cultures and cytology of her uterus to determine her candidacy. Consider her age, foaling history, and overall condition. Foaling is perilous for both mares and foals, with tragic outcomes not uncommon, despite expert care. Despite our extensive experience, each foaling remains a mix of excitement and anxiety. Witnessing our mares in labor is always stressful, and relief floods us when a foal safely arrives. But let's backtrack. What's next after carefully selecting a mare? 

 Choosing between fresh and frozen semen significantly influences stallion selection. Importing semen from Europe entails permits and substantial expenses, with only frozen semen viable due to shipping timeframes. Using a broker experienced in European semen imports is advisable, as they handle paperwork, permits, insurance, and coordinate with stallion stations, often pooling shipments to mitigate costs. Opting for fresh semen simplifies matters but confines choices to North American stallions. While USA/Canadian fresh semen shipments are possible, reliance on shipping companies poses risks, as delayed or compromised deliveries can disrupt breeding schedules, incurring additional expenses without recourse. Fresh semen typically comes with a Live Foal Guarantee (LFG), ensuring the delivery of a viable foal, though additional costs like shipping and collection fees persist. Frozen semen presents greater challenges, with no guarantees and reliance on skilled veterinarians for successful breeding. Mare owners may invest in doses of semen without achieving desired results, highlighting the complexities and uncertainties inherent in breeding with frozen semen. 

Using frozen semen offers the advantage of convenience, as it can be thawed and used when needed. However, this convenience comes with its own set of costs and challenges. Frozen semen must be stored in liquid nitrogen tanks, which require constant maintenance and topping up every 6 weeks to maintain the required freezing temperature. The veterinary procedures involved are more complex and intensive. Thawing semen can damage its motility, necessitating insemination as close to ovulation as possible. To achieve this, the mare undergoes frequent ultrasounds, every 6 hours until ovulation is confirmed. This intensive monitoring can result in numerous ultrasounds, with some mares requiring over 10 before ovulation occurs. The insemination process itself demands skill, typically utilizing a technique called deep horn insemination, which requires precise placement of the insemination rod into the uterus. Post-breeding management of mares inseminated with frozen semen is also more involved, as it can induce an inflammatory reaction requiring uterine flushes and anti-inflammatory medications. Additionally, mares may receive medication to promote uterine contraction and clear any fluid accumulation. It's worth noting that horses sired by stallions outside North America likely resulted from the use of frozen semen. In the image to the right is our frozen semen storage tank.

 After carefully selecting a stallion and completing the breeding process with either fresh or frozen semen, or even attempting an embryo transfer, it's now a waiting game. Two weeks after ovulation or one week after embryo transfer, the mare undergoes an ultrasound to check for pregnancy. This step is crucial, as it allows the veterinarian to detect any potential twins, which can be dangerous if left undiagnosed. If twins are found, it's imperative to reduce them to one embryo for the safety of the mare and foals. Undertaking reduction early by an experienced veterinarian is essential to prevent the loss of the entire pregnancy. Following a reduction, the mare is typically placed on progesterone to maintain the pregnancy until she's well into gestation. A follow-up ultrasound at 28 days confirms embryo development and the presence of a heartbeat. Many breeders opt for a 60-day ultrasound to ensure the mare remains pregnant before the end of the breeding season. In the image to the right is the same embryo retrieved earlier, now 7 days later in the recipient mare, due in July 2024. 

 Horses, unlike humans, generally deliver their foals very quickly once the water breaks. Delivery typically occurs within 30 minutes of the water breaking, and a veterinarian should be contacted if the mare hasn't delivered by this time, or earlier if she doesn't seem to be progressing normally. The foal should arrive with both front feet first, followed by the nose and shoulders. Once the shoulders are delivered, the rest of the foal usually slides out easily. It's important to note that certain time-sensitive emergencies can occur if the feet aren't presenting first, but discussing those is beyond the scope of this page. Assuming all goes well, the moment you've been waiting for over the last 1.5 years has finally arrived!

After the mare foals, ideally, she should deliver the placenta within 30 minutes. Retained placenta can become an emergency if not managed quickly, so consult a veterinarian for guidance or assessment if it's not delivered within this time frame. Once the placenta is delivered it should be evaluated for signs of infection, and to ensure it's complete.  Additionally, the mare should be closely monitored for colic symptoms, haver her temperature taken, and managed accordingly if required. 

 The next milestone for the foal is passing urine and meconium, which ideally should occur within 6 hours of birth. To prevent meconium impaction, we routinely administer an enema to the foals. Meconium, the first manure from a foal, is very hard and can be challenging to pass. Straining excessively to pass it can result in a hernia. Shortly after birth, we begin dipping the umbilical cord in a chlorhexidine solution to prevent infection.

Mares typically foal during the night, although we've had the rare occurrence of two mares foaling during the day out of over 25 foals. Once these milestones have been met, we usually take a rest if possible before having the veterinarian assess the foal in the morning. The veterinarian examines the foal for any birth defects or abnormalities and may draw blood for evaluation. All our foals undergo IGG testing to confirm they received enough good-quality colostrum to keep them healthy and prevent infections. Foals are particularly vulnerable during the first month of life, as diseases in the environment can overwhelm their immune systems. While we maintain cleanliness in the mare and foal's stall, we can't control the bacteria in the ground or from other horses on the property.

Around 7-10 days old, foals often develop what's commonly known as 'foal heat diarrhea.' The exact cause is unclear, with speculations about worms and hormone changes in the mare possibly contributing. Managing foals with diarrhea can be challenging and may require veterinary care. Some cases require antibiotics, while others resolve with minor medication or on their own. Dehydration is a significant concern, as it can be life-threatening. Aggressive treatment of diarrhea can also lead to constipation and straining, potentially resulting in a hernia.

 By now, you've likely noticed the significant expenses that accumulate from the decision to breed a mare. We often hear comments like "the stud fee was only $2000, why is the foal so expensive?" These remarks can be frustrating because we genuinely believe that many people don't understand the extensive process involved in breeding a mare, maintaining her pregnancy, foaling out, and successfully raising the foal to weaning. Despite pricing our foals in the normal to high range, we rarely make a profit. We spare no expense on the mares and foals, always adhering to proper procedures without cutting corners.  

Expenses not mentioned so far include mare maintenance for trims, feed, deworming, vaccines, and any necessary emergency care while pregnant, as well as costs for foaling cameras, paddock and farm maintenance, storage fees for frozen semen, rental of shipping tanks, liquid nitrogen top-ups, membership fees to breed registries, registering and inspecting the foal, insurance, and the costs associated with open mares that don't produce a foal every year. Some breeders may have an advantage because they are able to grow their own hay, and produce their own feed.  We don't have a big enough property to grow our feed, so we purchase it.  Hay is  out all year, we provide hay even in the summer months. We have two recipient mares, one of which has been open for two years awaiting an embryo to receive. It's costly to keep unproductive horses around.

Our first broodmare, Eclipse, gave us five fantastic foals and has been retired for 10 years, happily looking after her grandkids. She's 28 years old, and we'll continue to provide her with the retirement she deserves as long as she's happy and healthy. Eclipse is pictured to the left with four youngsters she's helping to raise as the matriarch of the herd. We've also experienced many losses over the years. Imagine the expense of getting a mare pregnant, only for her to lose the foal over the winter. All the money spent on feeding, care, veterinary bills, and possibly frozen semen is essentially wasted, requiring starting over from scratch. Even worse, a foal may be successfully delivered, only to succumb to an environmental disease within 30 days despite all efforts to save it. These situations take a massive emotional toll on the breeder, in addition to the financial blow. We've spent over $10,000 in veterinary care trying to save a foal, only to have it not survive. At that point, all the money invested in breeding, maintaining, and additional expenses results in no foal to sell. These tragedies can lead breeders to give up on breeding due to the immense burden.