Breeding

Equine coital exanthema in horses is an EHV-3 infection with an important practical consequence: a mare or stallion may appear healthy yet still need to be withdrawn from breeding. Even a mild case can cause significant discomfort and disrupt breeding...

Centuries of selective breeding shaped the modern horse breeds we know and love. Today, the unique history and characteristics of each breed are maintained by organizations that establish rules defining which horses are eligible for official registration with the breed's...

Lactation is a vital process for broodmares, ensuring the survival and growth of foals by providing essential nutrients and immune protection. However, some mares experience abnormal or inappropriate lactation, producing milk outside the expected timeline—either too early, too late, or...

Gestation in horses is a journey that requires care, knowledge, and preparation to ensure both the mare and foal remain healthy throughout the pregnancy. The average gestation period for a horse lasts around 340 days, though some mares may carry...

Horse coat colors are highly diverse and carry historical, cultural, and even functional significance within many horse breeds. The colors and patterns that mark these breeds result from a complex interaction of several genes that geneticists have studied for centuries....

Keeping stallions happy, healthy, and appropriately managed requires an understanding of their unique behavior compared to mares and geldings. Stallions often exhibit instinctive behaviors shaped by evolutionary pressures and social dynamics in the wild. Contrary to their natural environment with...

Breeders should observe all foalings as closely as possible to monitor the health and wellness of the mare and foal during this period of rapid transition. The 1-2-3-4 Rule is a helpful guideline for breeders to follow when evaluating their...

During fetal development, the testicles form near the kidneys and gradually descend into the scrotum through a passage called the inguinal canal. In some cases, this descent is incomplete, resulting in one or both testicles being retained within the abdomen...

A Breeding Soundness Exam (BSE) aims to evaluate your stallion’s overall health, reproductive anatomy, ability to perform in the breeding shed, and semen quality. This exam ensures your stallion is [...]

The overo pattern is one of three coat patterns in American Paint Horses (APHs) recognized by the American Paint Horse Association (APHA), along with Tobiano and Tovero. Among Overo variations, the frame overo subtype stands out for its distinctive markings....

Mastitis in mares is a condition characterized by the inflammation of the mammary gland, usually due to a bacterial infection. Mastitis typically affects lactating mares, often in the period immediately after giving birth or after weaning.

Foal rejection is a situation where the normal bonding between the mare and her foal fails to occur after birth. As a result, the mare may show disinterest, fear, or even aggression towards her newborn foal. The precise cause of...

The typical gestation period for horses ranges from 340 to 342 days. During this time, foals undergo extensive development of their organ and skeletal systems, ensuring their survival outside of the mare after birth. In some cases, foals are born...

The reproductive performance of broodmares holds significant importance within the equine industry. Achieving optimal pregnancy rates is critical for both the profitability of breeding operations and the holistic well-being of mares and foals. Many different factors can affect mare fertility,...

An orphan foal is a young horse that cannot nurse their birth mother. Foals may be orphaned for a number of reasons, including the mare’s death or severe illness, rejection of the foal, or the mare’s failure to produce adequate...

Despite ongoing advances in equine husbandry and veterinary care, achieving a full-term pregnancy in mares can be challenging. The foaling success rate is often measured below 60%, underscoring the complexities involved in equine reproduction. Breeding Soundness Exams (BSEs) are critical...

Contagious equine metritis (CEM) is a bacterial infection in horses caused by Taylorella equigenitalis. CEM is highly contagious and primarily spreads through venereal transmission and contact with contaminated breeding equipment. CEM is characterized by severe inflammation of the reproductive tract...

Donor colostrum ensures that a foal receives necessary immune support, even if colostrum is insufficient or unavailable from its mother. Breeders can collect and store their own donor colostrum or use the services of a colostrum bank.

The time around foaling (periparturient period) is a high-risk period for mares, as their bodies undergo many changes associated with delivery of the foal. Breeders must closely monitor their mares for signs of medical emergencies before, during, and after foaling....

Enlarged ovaries are frequently observed in mares, especially those used for breeding. This enlargement often stems from an ovarian cyst. In most instances, these cysts are benign and resolve spontaneously, typically not affecting the mare’s fertility. However, it’s crucial for...

Estrus manipulation involves altering the natural course of the mare’s reproductive cycle to support breeding program goals. Breeders may choose to manipulate the estrous cycle in order to increase the length of the breeding season, maximize chances of pregnancy after...

Stallions have unique nutrition and behavioral needs because of their high activity level and potential to become aggressive towards herd mates and humans. Often housed alone, stallions can develop stereotypic behaviours that further complicate their management. Young colts require consistent...

Assisted reproductive technologies (ARTs) are breeding techniques used to produce foals from subfertile mares and stallions. Some techniques, such as oocyte transfer, are primarily used for mares who are unable to carry a pregnancy to term or even produce embryos...

Natural service, or live cover, is a common breeding method in the horse industry in which a stallion and mare physically mate. This method is relatively inexpensive and requires less personnel involvement than artificial insemination. Breeders can choose between pasture...

Embryo transfer (ET) is an advanced reproductive technology that allows breeders to produce multiple offspring from a single mare in a given year. This procedure involves taking an embryo from a donor mare, and depositing it in the uterus of...

Equine viral arteritis (EVA) is a serious infectious disease that affects all equine species. EVA is particularly significant within breeding herds, as the disease causes abortion in up to 60% of affected pregnant mares. Many horses with equine viral arteritis...

Artificial insemination (AI) is an increasingly popular method of breeding mares, as it reduces many of the risks of natural service while providing several advantages. Benefits include accessing broader genetics, using stored or transported semen, and eliminating the need to...

Semen collection and evaluation is an important component of standing a stallion at stud. Semen collection for a breeding soundness evaluation allows owners to estimate how many mares their stallion can service in a year, determine overall semen quality, and...

Lavender Foal Syndrome (LFS), or coat colour dilution lethal (CCDL), is a rare and lethal disorder in Arabian horses and crossbreeds. Foals with LFS are born with neurological problems and a lightened coat colour. Lavender Foal Syndrome is a genetic...

Mare reproductive loss syndrome (MRLS) is an enigmatic condition first described in Kentucky in 2001, when an estimated 3,500 foals were either aborted, stillborn, or died shortly after birth. Research revealed that abortions and foal death was closely associated with...