Horse - breeding
Horse breeding is reproduction in horses, and particularly the human-directed process of selective breeding of animals, particularly purebred horses of a given breed.
Planned matings can be used to produce specifically desired characteristics in domesticated horses.
Furthermore, modern breeding management and technologies can increase the rate of conception, a healthy pregnancy, and successful foaling.
Reproduction and development - estation lasts for approximately 335–340 days and usually results in one foal. Twins are rare. Horses are a precocial species, and foals are capable of standing and running within a short time following birth.
Horses, particularly colts, sometimes are physically capable of reproduction at about 18 months, but domesticated horses are rarely allowed to breed before the age of three, especially females. Horses four years old are considered mature, although the skeleton normally continues to develop until the age of six; maturation also depends on the horse's size, breed, sex, and quality of care.
Planned matings can be used to produce specifically desired characteristics in domesticated horses.
Furthermore, modern breeding management and technologies can increase the rate of conception, a healthy pregnancy, and successful foaling.
Reproduction and development - estation lasts for approximately 335–340 days and usually results in one foal. Twins are rare. Horses are a precocial species, and foals are capable of standing and running within a short time following birth.
Horses, particularly colts, sometimes are physically capable of reproduction at about 18 months, but domesticated horses are rarely allowed to breed before the age of three, especially females. Horses four years old are considered mature, although the skeleton normally continues to develop until the age of six; maturation also depends on the horse's size, breed, sex, and quality of care.
Also, if the horse is larger, its bones are larger; therefore, not only do the bones take longer to actually form bone tissue, but also the epiphyseal plates are also larger and take longer to convert from cartilage to bone.
These plates convert after the other parts of the bones, and are crucial to development. Depending on maturity, breed, and work expected, horses are usually put under saddle and trained to be ridden between the ages of two and four.
Although Thoroughbred race horses are put on the track as young age two in some countries, horses specifically bred for sports such as dressage are generally not put under saddle until they are three or four years old, because their bones and muscles are not solidly developed. For endurance riding competition, horses are not deemed mature enough to compete until they are a full 60 calendar months (five years) old.
These plates convert after the other parts of the bones, and are crucial to development. Depending on maturity, breed, and work expected, horses are usually put under saddle and trained to be ridden between the ages of two and four.
Although Thoroughbred race horses are put on the track as young age two in some countries, horses specifically bred for sports such as dressage are generally not put under saddle until they are three or four years old, because their bones and muscles are not solidly developed. For endurance riding competition, horses are not deemed mature enough to compete until they are a full 60 calendar months (five years) old.
Terminology
The male parent of a horse, a stallion, is commonly known as the sire and the female parent, the mare, is called the dam. Both are genetically important, as each parent provides half of the genetic makeup of the ensuing offspring, called a foal. (Contrary to popular misuse, the word "colt" refers to a young male horse only; "filly" is a young female).
Though many horse owners may simply breed a family mare to a local stallion in order to produce a companion animal, most professional breeders use selective breeding to produce individuals of a given phenotype, or breed. Alternatively, a breeder could, using individuals of differing phenotypes, create a new breed with specific characteristics.
The male parent of a horse, a stallion, is commonly known as the sire and the female parent, the mare, is called the dam. Both are genetically important, as each parent provides half of the genetic makeup of the ensuing offspring, called a foal. (Contrary to popular misuse, the word "colt" refers to a young male horse only; "filly" is a young female).
Though many horse owners may simply breed a family mare to a local stallion in order to produce a companion animal, most professional breeders use selective breeding to produce individuals of a given phenotype, or breed. Alternatively, a breeder could, using individuals of differing phenotypes, create a new breed with specific characteristics.
A horse is "bred" where it is foaled (born). Thus a foal conceived in England but foaled in the United States is regarded as being bred in the US. In some cases, most notably in the Thoroughbred breeding industry.
American-bred horses may also be described by the state in which they are foaled. Some breeds denote the country, or state, where conception took place as the origin of the foal.Similarly, the "breeder", is the person who owned or leased the mare at the time of foaling.
That individual may not have had anything to do with the mating of the mare. It's important to review each breed registry's rules to determine which applies to any specific foal.
American-bred horses may also be described by the state in which they are foaled. Some breeds denote the country, or state, where conception took place as the origin of the foal.Similarly, the "breeder", is the person who owned or leased the mare at the time of foaling.
That individual may not have had anything to do with the mating of the mare. It's important to review each breed registry's rules to determine which applies to any specific foal.
In the horse breeding industry, the term "half-brother" or "half-sister" only describes horses which have the same dam, but different sires. Horses with the same sire but different dams are simply said to be "by the same sire", and no sibling relationship is implied. "Full" (or "own") siblings have both the same dam and the same sire.
The terms paternal half-sibling, and maternal half-sibling are also often used. Three-quarter siblings are horses out of the same dam, and are by sires that are either half-brothers (i.e. same dam) or who are by the same sire.
Thoroughbreds and Arabians are also classified through the "distaff" or direct female line, known as their "family" or "tail female" line, tracing back to their taproot foundation bloodstock or the beginning of their respective stud books. The female line of descent always appears at the bottom of a tabulated pedigree and is therefore often known as the bottom line.
"Linebreeding" technically is the duplication of fourth generation or more distant ancestors. However, the term is often used more loosely, describing horses with duplication of ancestors closer than the fourth generation. It also is sometimes used as a euphemism for the practice of inbreeding, a practice that is generally frowned upon by horse breeders, though used by some in an attempt to fix certain traits.
The terms paternal half-sibling, and maternal half-sibling are also often used. Three-quarter siblings are horses out of the same dam, and are by sires that are either half-brothers (i.e. same dam) or who are by the same sire.
Thoroughbreds and Arabians are also classified through the "distaff" or direct female line, known as their "family" or "tail female" line, tracing back to their taproot foundation bloodstock or the beginning of their respective stud books. The female line of descent always appears at the bottom of a tabulated pedigree and is therefore often known as the bottom line.
"Linebreeding" technically is the duplication of fourth generation or more distant ancestors. However, the term is often used more loosely, describing horses with duplication of ancestors closer than the fourth generation. It also is sometimes used as a euphemism for the practice of inbreeding, a practice that is generally frowned upon by horse breeders, though used by some in an attempt to fix certain traits.
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Breeding and gestation
While horses in the wild mate and foal in mid to late spring, in the case of horses domestically bred for competitive purposes, especially horse racing and various futurities, it is desirable that they be born as close to January 1 in the northern hemisphere or August 1 in the southern hemisphere as possible, so as to be at an advantage in size and maturity when competing against other horses in the same age group.
When an early foal is desired, barn managers will put the mare "under lights" by keeping the barn lights on in the winter to simulate a longer day, thus bringing the mare into estrus sooner than she would in nature. Mares signal estrus and ovulation by urination in the presence of a stallion, raising the tail and revealing the vulva. A stallion, approaching with a high head, will usually nicker, nip and nudge the mare, as well as sniff her urine to determine her readiness for mating.
Once fertilized, the oocyte (egg) remains in the oviduct for approximately 5.5 more days, and then descends into the uterus. The initial single cell combination is already dividing and by the time of entry into the uterus, the egg might have already reached the blastocyst stage.
While horses in the wild mate and foal in mid to late spring, in the case of horses domestically bred for competitive purposes, especially horse racing and various futurities, it is desirable that they be born as close to January 1 in the northern hemisphere or August 1 in the southern hemisphere as possible, so as to be at an advantage in size and maturity when competing against other horses in the same age group.
When an early foal is desired, barn managers will put the mare "under lights" by keeping the barn lights on in the winter to simulate a longer day, thus bringing the mare into estrus sooner than she would in nature. Mares signal estrus and ovulation by urination in the presence of a stallion, raising the tail and revealing the vulva. A stallion, approaching with a high head, will usually nicker, nip and nudge the mare, as well as sniff her urine to determine her readiness for mating.
Once fertilized, the oocyte (egg) remains in the oviduct for approximately 5.5 more days, and then descends into the uterus. The initial single cell combination is already dividing and by the time of entry into the uterus, the egg might have already reached the blastocyst stage.
The gestation period lasts for about eleven months, or about 340 days (normal average range 320–370 days). During the early days of pregnancy, the conceptus is mobile, moving about in the uterus until about day 16 when "fixation" occurs. Shortly after fixation, the embryo proper (so called up to about 35 days) will become visible on trans-rectal ultrasound (about day 21) and a heartbeat should be visible by about day 23. After the formation of the endometrial cups and early placentation is initiated (35–40 days of gestation) the terminology changes, and the embryo is referred to as a fetus.
True implantation - invasion into the endometrium of any sort - does not occur until about day 35 of pregnancy with the formation of the endometrial cups, and true placentation (formation of the placenta) is not initiated until about day 40-45 and not completed until about 140 days of pregnancy.
The fetus sex can be determined by day 70 of the gestation using ultrasound. Halfway through gestation the fetus is the size of between a rabbit and a beagle. The most dramatic fetal development occurs in the last 3 months of pregnancy when 60% of fetal growth occurs. Colts are carried on average about 4 days longer than fillies.
True implantation - invasion into the endometrium of any sort - does not occur until about day 35 of pregnancy with the formation of the endometrial cups, and true placentation (formation of the placenta) is not initiated until about day 40-45 and not completed until about 140 days of pregnancy.
The fetus sex can be determined by day 70 of the gestation using ultrasound. Halfway through gestation the fetus is the size of between a rabbit and a beagle. The most dramatic fetal development occurs in the last 3 months of pregnancy when 60% of fetal growth occurs. Colts are carried on average about 4 days longer than fillies.
Care of the pregnant mare
Domestic mares receive specific care and nutrition to ensure that they and their foals are healthy. Mares are given vaccinations against diseases such as the Rhinopneumonitis (EHV-1) virus (which can cause abortions) as well as vaccines for other conditions that may occur in a given region of the world. Pre-foaling vaccines are recommended 4–6 weeks prior to foaling to maximize the immunoglobulin content of the colostrum in the first milk.
Deworming the mare a few weeks prior to foaling is also important, as the mare is the primary source of parasites for the foal. Mares can be used for riding or driving during most of their pregnancy, and it's healthy for them to have exercise. But only moderate exercise, especially when they become heavy in foal. Exercise in excessively high temperatures has been suggested as being detrimental to pregnancy maintenance during the embryonic period - it should however be noted that ambient temperatures encountered during the research were in the region of 100 degrees F and the same results may not be encountered in regions with lower ambient temperatures.
Domestic mares receive specific care and nutrition to ensure that they and their foals are healthy. Mares are given vaccinations against diseases such as the Rhinopneumonitis (EHV-1) virus (which can cause abortions) as well as vaccines for other conditions that may occur in a given region of the world. Pre-foaling vaccines are recommended 4–6 weeks prior to foaling to maximize the immunoglobulin content of the colostrum in the first milk.
Deworming the mare a few weeks prior to foaling is also important, as the mare is the primary source of parasites for the foal. Mares can be used for riding or driving during most of their pregnancy, and it's healthy for them to have exercise. But only moderate exercise, especially when they become heavy in foal. Exercise in excessively high temperatures has been suggested as being detrimental to pregnancy maintenance during the embryonic period - it should however be noted that ambient temperatures encountered during the research were in the region of 100 degrees F and the same results may not be encountered in regions with lower ambient temperatures.
During the last 3–4 months of gestation, rapid growth of the fetus increases the pregnant mare's nutritional requirements. Energy requirements during these last few months, and during the first few months of lactation are similar to those of a horse in full training.
Trace minerals such as Copper are extremely important, particularly during the tenth month of pregnancy, for proper skeletal formation.
Many feeds designed for pregnant and lactating mares provide the careful balance required of increased protein, increased calories through extra fat as well as vitamins and minerals. During the first several months of pregnancy, the nutritional requirements do not increase significantly since the rate of growth of the fetus is very slow. However, during this time, the mare should be provided supplemental vitamins and minerals, particularly if forage quality is questionable. Overfeeding the pregnant mare, particularly during early gestation, should be avoided, as excess weight may contribute to difficulties foaling or fetal/foal related problems.
Trace minerals such as Copper are extremely important, particularly during the tenth month of pregnancy, for proper skeletal formation.
Many feeds designed for pregnant and lactating mares provide the careful balance required of increased protein, increased calories through extra fat as well as vitamins and minerals. During the first several months of pregnancy, the nutritional requirements do not increase significantly since the rate of growth of the fetus is very slow. However, during this time, the mare should be provided supplemental vitamins and minerals, particularly if forage quality is questionable. Overfeeding the pregnant mare, particularly during early gestation, should be avoided, as excess weight may contribute to difficulties foaling or fetal/foal related problems.
Foaling
Mares due to foal are usually separated from other horses, both for the benefit of the mare and the safety of the soon-to-be-delivered foal. In addition, separation allows the mare to be monitored more closely by humans for any problems that may occur while giving birth. In the northern hemisphere a special foaling stall that is large and clutter free is frequently used, particularly by major breeding farms.
Originally, this was due in part to a need for protection from the harsh winter climate present when mares foal early in the year, but even in moderate climates, such as Florida, foaling stalls are still common because they allow closer monitoring of mares.
Mares due to foal are usually separated from other horses, both for the benefit of the mare and the safety of the soon-to-be-delivered foal. In addition, separation allows the mare to be monitored more closely by humans for any problems that may occur while giving birth. In the northern hemisphere a special foaling stall that is large and clutter free is frequently used, particularly by major breeding farms.
Originally, this was due in part to a need for protection from the harsh winter climate present when mares foal early in the year, but even in moderate climates, such as Florida, foaling stalls are still common because they allow closer monitoring of mares.
Smaller breeders often use a small pen with a large shed for foaling, or they may remove a wall between two box stalls in a small barn to make a large stall. In the milder climates seen in much of the southern hemisphere, most mares foal outside, often in a paddock built specifically for foaling, especially on the larger stud farms. Many stud farms worldwide employ technology to alert human managers when the mare is about to foal, including webcams, closed-circuit television, or assorted types of devices that alert a handler via a remote alarm when a mare lies down in a position to foal. On the other hand, some breeders, particularly those in remote areas or with extremely large numbers of horses, may allow mares to foal out in a field amongst a herd, but may also see higher rates of foal and mare mortality in doing so.
Most mares foal at night or early in the morning, and prefer to give birth alone when possible. Labor is rapid, often no more than 30 minutes, and from the time the feet of the foal appear to full delivery is often only about 15 to 20 minutes.
Once the foal is born, the mare will lick the newborn foal to clean it and help blood circulation. In a very short time, the foal will attempt to stand and get milk from its mother. A foal should stand and nurse within the first hour of life.
To create a bond with her foal, the mare licks and nuzzles the foal, enabling her to distinguish hers from others. Some mares are aggressive when protecting their foals, and may attack other horses or unfamiliar humans that come near their newborns.
After birth, a foal's navel is dipped in antiseptic to prevent infection, it is sometimes given an enema to help clear the meconium from its digestive tract, and the newborn is monitored to ensure that it stands and nurses without difficulty. While most horse births happen without complications, many owners have first aid supplies prepared and a veterinarian on call in case of a birthing emergency.
People who supervise foaling should also watch the mare to be sure that she passes the placenta in a timely fashion, and that it is complete with no fragments remaining in the uterus, where retained fetal membranes could cause a serious inflammatory condition (endometritis) and/or infection. If the placenta is not removed from the stall after it is passed, a mare will often eat it, an instinct from the wild, where blood would attract predators.
Once the foal is born, the mare will lick the newborn foal to clean it and help blood circulation. In a very short time, the foal will attempt to stand and get milk from its mother. A foal should stand and nurse within the first hour of life.
To create a bond with her foal, the mare licks and nuzzles the foal, enabling her to distinguish hers from others. Some mares are aggressive when protecting their foals, and may attack other horses or unfamiliar humans that come near their newborns.
After birth, a foal's navel is dipped in antiseptic to prevent infection, it is sometimes given an enema to help clear the meconium from its digestive tract, and the newborn is monitored to ensure that it stands and nurses without difficulty. While most horse births happen without complications, many owners have first aid supplies prepared and a veterinarian on call in case of a birthing emergency.
People who supervise foaling should also watch the mare to be sure that she passes the placenta in a timely fashion, and that it is complete with no fragments remaining in the uterus, where retained fetal membranes could cause a serious inflammatory condition (endometritis) and/or infection. If the placenta is not removed from the stall after it is passed, a mare will often eat it, an instinct from the wild, where blood would attract predators.
Foals develop rapidly, and within a few hours a wild foal can travel with the herd. In domestic breeding, the foal and dam are usually separated from the herd for a while, but within a few weeks are typically pastured with the other horses. A foal will begin to eat hay, grass and grain alongside the mare at about 4 weeks old; by 10–12 weeks the foal requires more nutrition than the mare's milk can supply. Foals are typically weaned at 4–8 months of age, although in the wild a foal may nurse for a year.
History of horse breeding
The history of horse breeding goes back millennia. Though the precise date is in dispute, humans could have domesticated the horse as far back as approximately 4500 BCE. However, evidence of planned breeding has a more blurry history.
One of the earliest people known to document the breedings of their horses were the Bedouin of the Middle East, the breeders of the Arabian horse.
While it is difficult to determine how far back the Bedouin passed on pedigree information via an oral tradition, there were written pedigrees of Arabian horses by A.D. 1330. The Akhal-Teke of West-Central Asia is another breed with roots in ancient times that was also bred specifically for war and racing. The nomads of the Mongolian steppes bred horses for several thousand years as well.
The types of horse bred varied with culture and with the times. The uses to which a horse was put also determined its qualities, including smooth amblers for riding, fast horses for carrying messengers, heavy horses for plowing and pulling heavy wagons, ponies for hauling cars of ore from mines, packhorses, carriage horses and many others.
The history of horse breeding goes back millennia. Though the precise date is in dispute, humans could have domesticated the horse as far back as approximately 4500 BCE. However, evidence of planned breeding has a more blurry history.
One of the earliest people known to document the breedings of their horses were the Bedouin of the Middle East, the breeders of the Arabian horse.
While it is difficult to determine how far back the Bedouin passed on pedigree information via an oral tradition, there were written pedigrees of Arabian horses by A.D. 1330. The Akhal-Teke of West-Central Asia is another breed with roots in ancient times that was also bred specifically for war and racing. The nomads of the Mongolian steppes bred horses for several thousand years as well.
The types of horse bred varied with culture and with the times. The uses to which a horse was put also determined its qualities, including smooth amblers for riding, fast horses for carrying messengers, heavy horses for plowing and pulling heavy wagons, ponies for hauling cars of ore from mines, packhorses, carriage horses and many others.
Medieval Europe bred large horses specifically for war, called destriers. These horses were the ancestors of the great heavy horses of today, and their size was preferred not simply because of the weight of the armor, but also because a large horse provided more power for the knight’s lance. Weighing almost twice as much as a normal riding horse, the destrier was a powerful weapon in battle.
On the other hand, during this same time, lighter horses were bred in northern Africa and the Middle East by Muslim warriors, who preferred a faster, more agile horse. The lighter horse suited the raids and battles of the Bedouins, allowing them to outmaneuver rather than overpower the enemy. When Muslim warriors and European knights collided in warfare, the heavy knights were frequently outmaneuvered.
The Europeans, however, soon made up for the lack of speed of their native breeds by incorporating genetic traits from captured oriental horses such as the Arabian, Barb to their stables.
This cross-breeding led both to a nimbler war horse, such as today's Percheron, but also to created a type of horse known as a Courser, a predecessor to the Thoroughbred, which was used as a message horse.
During the Renaissance, horses were bred not only for war, but for haute ecole riding, derived from the most athletic movements required of a war horse, and popular among the elite nobility of the time. Breeds such as the Lipizzan were developed from Spanish-bred horses for this purpose, and also became the preferred mounts of cavalry officers, who were derived mostly from the ranks of the nobility. It was during this time that gunpowder was developed, and so the light cavalry horse, a faster and quicker war horse, was bred for a “shoot and run” tactic rather than the close hand-to-hand fighting seen in the Middle Ages.
On the other hand, during this same time, lighter horses were bred in northern Africa and the Middle East by Muslim warriors, who preferred a faster, more agile horse. The lighter horse suited the raids and battles of the Bedouins, allowing them to outmaneuver rather than overpower the enemy. When Muslim warriors and European knights collided in warfare, the heavy knights were frequently outmaneuvered.
The Europeans, however, soon made up for the lack of speed of their native breeds by incorporating genetic traits from captured oriental horses such as the Arabian, Barb to their stables.
This cross-breeding led both to a nimbler war horse, such as today's Percheron, but also to created a type of horse known as a Courser, a predecessor to the Thoroughbred, which was used as a message horse.
During the Renaissance, horses were bred not only for war, but for haute ecole riding, derived from the most athletic movements required of a war horse, and popular among the elite nobility of the time. Breeds such as the Lipizzan were developed from Spanish-bred horses for this purpose, and also became the preferred mounts of cavalry officers, who were derived mostly from the ranks of the nobility. It was during this time that gunpowder was developed, and so the light cavalry horse, a faster and quicker war horse, was bred for a “shoot and run” tactic rather than the close hand-to-hand fighting seen in the Middle Ages.
After Charles II retook the British throne in 1660, horse racing, which had been banned by Cromwell, was revived. The Thoroughbred was developed 40 years later, bred to be the ultimate racehorse, through the lines of 3 foundation Arabian stallions.
In the 18th century, James Burnett, Lord Monboddo noted the importance of selecting appropriate parentage to achieve desired outcomes of successive generations. Monboddo worked more broadly in the abstract thought of species relationships and evolution of species.
The Thoroughbred breeding hub in Lexington, Kentucky was developed in the late 18th century, and became a mainstay in American racehorse breeding.
The 17th and 18th centuries saw more of a need for fine carriage horses in Europe, bringing in the dawn of the warmblood. The warmblood breeds have been exceptionally good at adapting to changing times, and from their carriage horse beginnings they easily transitioned during the 20th century into a sport horse type. Today’s warmblood breeds, although still used for competitive driving, are more often seen competing in the show jumping or dressage arenas.
In the 18th century, James Burnett, Lord Monboddo noted the importance of selecting appropriate parentage to achieve desired outcomes of successive generations. Monboddo worked more broadly in the abstract thought of species relationships and evolution of species.
The Thoroughbred breeding hub in Lexington, Kentucky was developed in the late 18th century, and became a mainstay in American racehorse breeding.
The 17th and 18th centuries saw more of a need for fine carriage horses in Europe, bringing in the dawn of the warmblood. The warmblood breeds have been exceptionally good at adapting to changing times, and from their carriage horse beginnings they easily transitioned during the 20th century into a sport horse type. Today’s warmblood breeds, although still used for competitive driving, are more often seen competing in the show jumping or dressage arenas.
The Thoroughbred continues to dominate the horseracing world, although its lines have been more recently used to improve warmblood breeds and to develop sport horses.
The predecessor of the American Quarter Horse was developed in the 18th century, mainly for quarter racing (racing ¼ of a mile). The breed was later adapted for work in the west, and “cow sense” was particularly bred for as their use for herding cattle increased. However, because there was also a need for animals suitable for sprint racing, the modern Quarter
Horse has two distinct types: the sleeker racing type and the stock horse type. The racing type most resembles the finer-boned ancestors of the first racing Quarter Horses, and the type is still used for ¼-mile races. The stock horse type, used in western events, is bred for a shorter stride, docile temperament, and cow sense.
The need for horses for heavy draft and carriage work continued until the industrial revolution and the advent of the automobile and the tractor. After this time, draft and carriage horse numbers dropped significantly, though light riding horses remained popular for recreational pursuits. Draft horses today are used on a few small farms, but today are seen mainly for pulling and plowing competitions rather than farm work. Heavy harness horses are now used as an outcross with lighter breeds, such as the Thoroughbred, to produce the modern warmblood breeds popular in Olympic and sport horse disciplines.
Source
The predecessor of the American Quarter Horse was developed in the 18th century, mainly for quarter racing (racing ¼ of a mile). The breed was later adapted for work in the west, and “cow sense” was particularly bred for as their use for herding cattle increased. However, because there was also a need for animals suitable for sprint racing, the modern Quarter
Horse has two distinct types: the sleeker racing type and the stock horse type. The racing type most resembles the finer-boned ancestors of the first racing Quarter Horses, and the type is still used for ¼-mile races. The stock horse type, used in western events, is bred for a shorter stride, docile temperament, and cow sense.
The need for horses for heavy draft and carriage work continued until the industrial revolution and the advent of the automobile and the tractor. After this time, draft and carriage horse numbers dropped significantly, though light riding horses remained popular for recreational pursuits. Draft horses today are used on a few small farms, but today are seen mainly for pulling and plowing competitions rather than farm work. Heavy harness horses are now used as an outcross with lighter breeds, such as the Thoroughbred, to produce the modern warmblood breeds popular in Olympic and sport horse disciplines.
Source
