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69-514: The initials LWS may refer to: Lethal white syndrome , a genetic disorder of horses Lewiston-Nez Perce County Airport , Idaho, US LWS (aircraft manufacturer) , Poland, 1936-1939 Living With a Star Lewes railway station , a railway station in Sussex, England Let Women Speak Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with

138-407: A 25% chance exists of a LWS foal. Spotted coat colors, including frame, are popular and sought-after by breeders. While many lethal white syndrome foals are accidentally produced when breeders cross two untested cryptic frames, or a known frame and a cryptic frame, some are produced by the intentional breeding of two known frames, whether out of ignorance or indifference. Producing a foal with LWS

207-461: A better understanding of coat color genetics or even waiting 12 hours or so for the foal to develop clinical signs. The availability of testing also allows a breeder to determine if a white-coated, blue-eyed foal that becomes ill is an LWS foal that requires euthanasia or a non-LWS foal with a simple illness that may be successfully treated. From very early in research into its genetics, LWS has been compared to Hirschsprung's disease in humans, which

276-498: A dominant pattern of inheritance, deviations occur. The majority of horses with the Ile118Lys mutation do exhibit the recognizable frame pattern, but a small percentage are too modestly marked to be classified as "spotted" by breed registries. Such "solid" horses, bred to a solid partner, can produce classically marked frames. The "crop-out" phenomenon can make frame appear to follow a recessive mode of inheritance. The gene for LWS

345-433: A horse as an unspotted solid is based not on genetic testing, but on a visual description. Horses carrying genetics for frame and other white-spotting patterns may be so minimally marked as to lack the registry's minimum requirements for white. This helps to account for allegedly solid horses producing spotted offspring, called cropouts . The long-standing practice of categorizing Paint horses in this manner contributed to

414-426: A human. In essence, a horse travels on its "tiptoes". The hoof wall is a much larger, thicker and stronger version of the human fingernail or toenail, made up of similar materials, primarily keratin , a very strong protein molecule. The horse's hoof contains a high proportion of sulfur -containing amino acids which contribute to its resilience and toughness. Vascular fold-like structures called laminae suspend

483-433: A joint) or extensors (extend a joint). However, some tendons will flex multiple joints while extending another (the flexor tendons of the hind limb, for example, will flex the fetlock , pastern, and coffin joint, but extend the hock joint). In this case, the tendons (and associated muscles) are named for their most distal action (digital flexion). Tendons form in the embryo from fibroblasts which become more tightly packed as

552-420: A lethal white syndrome foal. Therefore, breeding two frame overos conveys no benefit to breeders hoping to produce another frame overo. Lethal white syndrome has been described by researchers as both dominantly and recessively inherited. Lethal white syndrome is described as recessive because heterozygotes (written Oo or N/O ) are not affected by intestinal agangliosis. However, if the frame pattern trait

621-454: A non-glandular proximal region (saccus cecus), divided by a distinct border, the margo plicatus, from the glandular distal stomach. In the stomach, assorted acids and the enzyme pepsin break down food. Pepsin allows for the further breakdown of proteins into amino acid chains. Other enzymes include resin and lipase . Additionally, the stomach absorbs some water, as well as ions and lipid-soluble compounds. The horse's small intestine

690-404: A rough estimate of a horse's age can be made from an examination of the teeth. Abnormal wear of the teeth, caused by conformational defects, abnormal behaviors, or improper diets, can cause serious health issues and can even result in the death of the horse. The hoof of the horse encases part of the second and all of the third phalanx of the lower limbs, analogous to the fingertip or toe tip of

759-519: A similar cause to Hirschsprung's disease in humans. A mutation in the middle of the endothelin receptor type B ( EDNRB ) gene causes lethal white syndrome when homozygous . Carriers, which are heterozygous —that is, have one copy of the mutated allele , but themselves are healthy—can now be reliably identified with a DNA test . Both parents must be carriers of one copy of the LWS allele for an affected foal to be born. Horses that are heterozygous for

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828-505: A variety of horse populations in North America suggests that the mutation occurred in early American history, perhaps in a Spanish-type horse. Horses heterozygous for the Ile118Lys mutation on the equine EDNRB gene—carriers of lethal white syndrome—usually exhibit a white-spotting pattern called "frame", or "frame overo ". Frame is characterized by jagged, sharply defined, horizontally oriented white patches that run along

897-425: Is bipartite , meaning the two uterine horns fuse into a relatively large uterine body (resembling a shortened bicornuate uterus or a stretched simplex uterus). Caudal to the uterus is the cervix, about 5 to 7 cm (2.0 to 2.8 in) long, which separates the uterus from the vagina. Usually 3.5 to 4 cm (1.4 to 1.6 in) in diameter with longitudinal folds on the interior surface, it can expand to allow

966-427: Is 15 to 21 m (50 to 70 ft) long and holds 38 to 45 L (10 to 12 US gal). This is the major digestive organ, and where most nutrients are absorbed. It has three parts, the duodenum , jejunum and ileum . The majority of digestion occurs in the duodenum while the majority of absorption occurs in the jejunum. Bile from the liver aids in digesting fats in the duodenum combined with enzymes from

1035-412: Is about 30 cm (1 ft) long, and acts as a holding chamber for waste matter, which is then expelled from the body via the anus. The mare's reproductive system is responsible for controlling gestation, birth, and lactation, as well as her estrous cycle and mating behavior. It lies ventral to the 4th or 5th lumbar vertebrae, although its position within the mare can vary depending on the movement of

1104-492: Is also caused by mutations on the EDNRB gene. Various polymorphisms on this gene result in intestinal agangliosis, in some cases attended by unusual pigmentation of the skin and eyes, and deafness. The occasionally attendant pigmentation condition in humans is called Waardenburg-Shah syndrome . The terms "piebald-lethal" and "spotting lethal" apply to similar conditions in mice and rats, respectively, both caused by mutations on

1173-451: Is carefully controlled by regulatory genes . Such regulatory genes include endothelin receptor type B ( EDNRB ). A mutation in the middle of the EDNRB gene, Ile118Lys, causes lethal white syndrome. In this mutation, a "typo" in the DNA mistakes isoleucine for lysine . The resulting EDNRB protein is unable to fulfill its role in the development of the embryo, limiting the migration of

1242-445: Is entirely or almost entirely white with underlying unpigmented pink skin. If pigmented regions are present, they may be any color, and are most common around the muzzle, underside of the barrel, and the hindquarters or tail. The eyes are blue. A few lethal white foals have been shown to be deaf. Healthy foals pass meconium , the first stool , soon after birth. Some healthy foals may require an enema to assist this process, but

1311-417: Is generally quite strong. Due to their relatively poor blood supply, ligament injuries generally take a long time to heal. Tendons are cords of connective tissue attaching muscle to bone, cartilage or other tendons. They are a major contributor to shock absorption, are necessary for support of the horse's body, and translate the force generated by muscles into movement. Tendons are classified as flexors (flex

1380-412: Is included, inheritance of the trait follows an incomplete dominant pattern. The concept of "recessive" and "dominant" antedate molecular biology and technically apply only to traits, not to genes themselves. In pleiotropic conditions, such as LWS, the application of "recessive" or "dominant" can be ambiguous. A separate issue is the nomenclature applied to the frame pattern itself. While it follows

1449-473: Is most common in the American Paint Horse, but occurs in any breed that may carry frame genetics, including American Quarter Horses, Appaloosas , Thoroughbreds , Morgan horses , miniature horses , Tennessee Walking Horses , and mustangs , as well as horses that are descended from these breeds. Only two Morgan horses have been identified as frame overos. Breeds that do not carry genes for

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1518-415: Is most commonly seen in high performance horses that gallop or jump. When a tendon is damaged the healing process is slow because tendons have a poor blood supply, reducing the availability of nutrients and oxygen to the tendon. Once a tendon is damaged the tendon will always be weaker, because the collagen fibres tend to line up in random arrangements instead of the stronger linear pattern. Scar tissue within

1587-511: Is now completely avoidable, because most major animal genetics labs now offer the DNA test for it. Whether a horse visually appears to have the frame pattern or not, testing horses of frame or "overo" lineage is highly recommended. The statistical likelihood of producing a living, frame-patterned foal by crossing two frames is 50%, the same odds of producing a living, frame-patterned foal from a frame-to-nonframe breeding which carries no risk of producing

1656-515: Is responsible for his sexual behavior and secondary sex characteristics (such as a large crest). The external genitalia include the urethra ; the testes , which average 8 to 12 cm (3.1 to 4.7 in) long; the penis , which, when housed within the prepuce, is 50 cm (20 in) long and 2.5 to 6 cm (0.98 to 2.36 in) in diameter with the distal end 15 to 20 cm (5.9 to 7.9 in) and when erect , increases by 3 to 4 times . The internal genitalia accessory sex glands are

1725-416: Is technically correct, but only because the term "overo" also encompasses splash and sabino patterns, as well as frame. Homozygotes for the Ile118Lys mutation on the equine endothelin receptor type B gene have lethal white syndrome. In any crossing of two carrier parents, the statistical probability of producing a solid-colored, living foal is 25%; a 50% chance exists for a frame-patterned, living foal; and

1794-423: The EDNRB gene. Only lethal in the homozygous state, the mutations are associated with white-spotted coats, deafness, and megacolon caused by intestinal agangliosis. Equine anatomy#Digestive system Equine anatomy encompasses the gross and microscopic anatomy of horses, ponies and other equids , including donkeys , mules and zebras . While all anatomical features of equids are described in

1863-412: The digestive system . The large intestine of the horse comprises the cecum , the colon , and the rectum . Necropsies on LWS foals reveal a pale, underdeveloped colon and intestinal obstruction (impaction). Samples of affected tissue show a lack of nerves that allow the intestine to move material through the digestive system, a condition called intestinal agangliosis . Closer examination of

1932-545: The hindgut consists of the cecum , large colon , small colon and rectum , terminating in the anus . The cecum (called the "water gut" in old textbooks) is the first section of the large intestine, analogous to the appendix in humans. It is a cul-de-sac pouch, about 1.2 m (4 ft) long that holds 26 to 30 L (7 to 8 US gal). It contains bacteria and other microbes that break down cellulose and other indigestible plant fiber through fermentation into volatile fatty acids . These microbes feed upon

2001-405: The pancreas and small intestine. Horses, in common with mammals such as camels, do not have a gall bladder , meaning bile flows constantly. Most food is digested and absorbed into the bloodstream from the small intestine, including proteins, simple carbohydrate, fats, and vitamins A, D, and E . Any remaining liquids and roughage move into the large intestine. The large intestine, also known as

2070-453: The tympanic membrane . Located between the mandibles but below the occiput , it fills with air when the horse swallows or exhales. The horse's circulatory system includes the four-chambered heart, averaging 3.9 kg (8.5 lb) in weight, as well as the blood and blood vessels. Its main purpose is to circulate blood throughout the body to deliver oxygen and nutrients to tissues, and to remove waste from these tissues. The hoof (including

2139-455: The vesicular glands , prostate gland , and bulbourethral glands , which contribute fluid to the semen at ejaculation , but are not strictly necessary for fertility. A horse's teeth include incisors , premolars , molars , and sometimes canine teeth. A horse's incisors, premolars, and molars, once fully developed, continue to erupt throughout its lifetime as the grinding surface is worn down through chewing. Because of this pattern of wear,

LWS - Misplaced Pages Continue

2208-415: The "overo" category were not frames, and conversely, 10% of horses registered as tobiano also carried frame genetics. The difficulty in accurately identifying frames has contributed to the accidental breeding of LWS foals. Minimally marked horses heterozygous for the Ile118Lys mutation are not uncommon: one DNA-tested Thoroughbred has white markings limited to a bottom-heavy blaze and two socks below

2277-595: The amount of feed a horse can take in at one time. The average sized horse (360 to 540 kg [800 to 1,200 lb]) has a stomach with a capacity of around 19 L (5 US gal), and works best when it contains about 7.6 L (2 US gal). Because the stomach empties when 2 ⁄ 3 full, whether stomach enzymes have completed their processing of the food or not, and doing so prevents full digestion and proper utilization of feed, continuous foraging or several small feedings per day are preferable to one or two large ones. The horse stomach consists of

2346-544: The confusion surrounding this disease. Currently, the American Paint Horse Association categorizes horses as tobiano, solid, "overo", and tovero . The association breaks down "overo" into three categories: Frame, Splash and Sabino. In the past, "overo" was used even more loosely, to refer to spotted animals that were "Paint, but not tobiano". However, no fewer than four—and likely many more—genetically distinct patterns are included under

2415-431: The digestive system of a horse is about 30 m (100 ft) long, and most of this is intestines. Digestion begins in the mouth, which is also called the "oral cavity." It is made up of the teeth, the hard palate, the soft palate, the tongue and related muscles, the cheeks and the lips. Horses also have three pairs of salivary glands, the parotoid (largest salivary gland and located near the poll), mandibular (located in

2484-566: The distal phalanx from the hoof wall. The skeleton of the horse has three major functions in the body. It protects vital organs, provides framework, and supports soft parts of the body. Horses have 205 bones , which are divided into the appendicular skeleton (the legs) and the axial skeleton (the skull , vertebral column , sternum , and ribs ). Both pelvic and thoracic limbs contain the same number of bones, 20 bones per limb. Bones are connected to muscles via tendons and other bones via ligaments. Bones are also used to store minerals, and are

2553-445: The end of each leg. Some of this effect may be lost when a horse is shod (eliminating the expansion and contraction of the hoof wall and raising the frog higher from the ground). The horse has one of the largest eyes of all land mammals. Eye size in mammals is significantly correlated to maximum running speed as well as to body size, in accordance with Leuckart's law ; animals capable of fast locomotion require large eyes. The eye of

2622-452: The fallopian tubes ( oviducts ), which serve to move the ovum from the ovary to the uterus. To do so, the oviducts are lined with a layer of cilia , which produce a current that flows toward the uterus. Each oviduct attaches to one of the two horns of the uterus, which are approximately 20 to 25 cm (7.9 to 9.8 in) in length. These horns attach to the body of the uterus (18 to 20 cm [7.1 to 7.9 in] long). The equine uterus

2691-557: The frame pattern also do not carry LWS. Not all white, blue-eyed foals are affected with LWS. Other genes can produce healthy pink-skinned, blue-eyed horses with a white or very light cream-colored coat. For a time, some of these completely white horses were called "living lethals", but this is a misnomer . Before reliable information and the DNA test were available to breeders, perfectly healthy, white-coated, blue-eyed foals were sometimes euthanized for fear they were lethal whites, an outcome which can be avoided today with testing and

2760-421: The frame pattern is masked. In particular, the tobiano pattern, a dominant gene, is epistatic to overo. Other white-spotting genes include splashed white or "splash", sabino, and "calico". Any combination, or all, of these white-spotting genes can act together to produce horses with so much white that the presence of frame cannot be determined without a DNA test. Ambiguous terminology has also contributed to

2829-514: The frog - the V-shaped part on the bottom of the horses hoof) is a very important part of the circulatory system. As the horse puts weight onto the hoof, the hoof wall is pushed outwards and the frog compressed, driving blood out of the frog, the digital pad, and the laminae of the hoof. When weight is removed from the hoof, the release of pressure pulls blood back down into the foot again. This effectively creates an auxiliary blood-pumping system at

LWS - Misplaced Pages Continue

2898-505: The gene that causes lethal white syndrome often exhibit a spotted coat color pattern commonly known as "frame" or "frame overo". Coat color alone does not always indicate the presence of LWS or carrier status, however. The frame pattern may be minimally expressed or masked by other spotting patterns. Also, different genetic mechanisms produce healthy white foals and have no connection to LWS, another reason for genetic testing of potential breeding stock. Some confusion also occurs because

2967-546: The heterozygous mutation exactly fit the standard visual description. A horse with the Ile118Lys mutation on EDNRB that is not readily identified as frame-patterned is called a cryptic frame. In addition to cryptic frames, a significant proportion of horses with the frame phenotype are visually misidentified, even in clinical settings. One study found from a group of visually inspected registered Paints, 18% of breeding stock solids and 35% of bald-faced horses were actually frames. However, over one-quarter of Paints registered in

3036-434: The horse from inhaling food, but also means that a horse cannot use its mouth to breathe when in respiratory distress—a horse can only breathe through its nostrils, also called obligate nasal breathing . For this same reason, horses also cannot pant as a method of thermoregulation . The genus Equus also has a unique part of the respiratory system called the guttural pouch , which is thought to equalize air pressure on

3105-417: The horse is set to the side of its skull, consistent with that of a prey animal. The horse has a wide field of monocular vision , as well as good visual acuity. Horses have two-color, or dichromatic vision , which is somewhat like red-green color blindness in humans. Because the horse's vision is closely tied to behavior, the horse's visual abilities are often taken into account when handling and training

3174-520: The horse's neck, shoulder, flank, and hindquarters. The frame pattern by itself does not produce white markings that cross the back, or affect the legs or tail. It does, however, often produce bald faces and blue eyes. The term "frame" describes the effect of viewing a frame-patterned horse from the side: the white markings appear to be "framed" by a dark-colored border. To date, animals which are heterozygous carriers do not exhibit health concerns associated with carrier-only status. Not all horses with

3243-423: The incorporation of the word "overo" into some of the titles used to describe the disease, such as overo lethal white foal syndrome. However, "overo" refers to several genetically unrelated white-spotting patterns, and only the frame pattern is indicative of the syndrome. The confusion about the nature of LWS is then furthered by statements such as "there are many overos that do not carry the lethal allele", which

3312-419: The intestines and distention of the bladder. The mare has two ovaries, usually 7 to 8 cm (2.8 to 3.1 in) in length and 3 to 4 cm (1.2 to 1.6 in) thick, that generally tend to decrease in size as the mare ages. In equine ovaries, unlike in humans, the vascular tissue is cortical to follicular tissue, so ovulation can only occur at an ovulation fossa near the infundibulum. The ovaries connect to

3381-450: The jaw), and sublingual (located under the tongue). Horses select pieces of forage and pick up finer foods, such as grain, with their sensitive, prehensile lips . The front teeth of the horse, called incisors , clip forage , and food is then pushed back in the mouth by the tongue , and ground up for swallowing by the premolars and molars . The esophagus is about 1.2 to 1.5 m (4 to 5 ft) in length, and carries food to

3450-421: The knee. A Quarter Horse mare tested positive for the gene after she and a frame Paint stallion produced a LWS foal; the mare's markings were a thin blaze with a disconnected white spot in the right nostril, with no other white markings. One major study identified two miniature horses that were completely unmarked, but were positive for the Ile118Lys gene. Multiple theories are given for this. Variability in

3519-440: The large colon is a common place for certain forms of colic including impaction, displacement and volvulus. The small colon is 3.0 to 3.7 m (10 to 12 ft) in length and holds only 19 L (5 US gal) of material. It is the area where the majority of water in the horse's diet is absorbed, and is the place where fecal balls are formed. This section is analogous to the descending colon in humans. The rectum

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3588-426: The meconium of LWS foals is impacted high in the intestine, and never appears, even with the use of enemas. Signs of colic begin to appear within the first day, and all foals with LWS die within the first few days of life. The painful and inevitable death that follows usually prompts veterinarians and owners to euthanize foals suspected of having lethal white syndrome. Death is caused by an underdeveloped part of

3657-504: The melanocyte and enteric neuron precursors. In the case of LWS, a single copy of the EDNRB mutation, the heterozygous state, produces an identifiable trait, but with a very different outcome from the homozygous state. To produce a foal with LWS, both parents must be heterozygotes or carriers of the mutated gene. Without genetic testing, some carriers are misidentified as having white markings due to another gene, while some are even classified as solids. The presence of this gene in

3726-444: The nostrils, pharynx, larynx, trachea, diaphragm, and lungs. Additionally, the nasolacrimal duct and sinuses are connected to the nasal passage. The horse's respiratory system not only allows the animal to breathe, but also is important in the horse's sense of smell (olfactory ability) as well as in communicating. The soft palate blocks off the pharynx from the mouth (oral cavity) of the horse, except when swallowing. This helps prevent

3795-420: The pair must be relaxed in order for the other muscle in the pair to contract and bend the joint properly. A muscle is made up of several muscle bundles, which in turn are made up of muscle fibers. Muscle fibers have myofibrils , which are able to contract due to actin and myosin . A muscle together with its tendon and bony attachments form an extensor or flexor unit. The horse's respiratory system consists of

3864-426: The passage of the foal. The vagina of the mare is 15 to 20 cm (5.9 to 7.9 in) long, and is quite elastic, allowing it to expand. The vulva is the external opening of the vagina, and consists of the clitoris and two labia. It lies ventral to the rectum. The mare has two mammary glands , which are smaller in maiden mares. They have two ducts each, which open externally. The stallion's reproductive system

3933-415: The percentage of individuals with a specific genotype that express an associated phenotype is called penetrance , and this may simply be evidence of variable penetrance. Several research groups have suggested that other, "suppressor" genes may limit the expression of frame-pattern white spotting. On the other end of the spectrum, some white-spotted horses are so extensively marked that the character of

4002-455: The portion of chyme not absorbed by the small intestine, and produce vitamin K and B complex vitamins . The large colon is 3.0 to 3.7 m (10 to 12 ft) long and holds up to 76 L (20 US gal) of semi-liquid matter. It is made up of the right ventral (lower) colon, the left ventral colon, the left dorsal (upper) colon, the right dorsal colon, and the transverse colon, in that order. Three flexures are also named:

4071-608: The same terms as for other animals by the International Committee on Veterinary Gross Anatomical Nomenclature in the book Nomina Anatomica Veterinaria , there are many horse-specific colloquial terms used by equestrians . Horses and other equids evolved as grazing animals, adapted to eating small amounts of the same kind of food all day long. In the wild, the horse adapted to eating prairie grasses in semi-arid regions and traveling significant distances each day in order to obtain adequate nutrition. Therefore,

4140-440: The site of red blood cell formation. The bones of the horse are the same as those of other domestic species, but the third metacarpal and metatarsal are much more developed and the second and fourth are undeveloped, having the first and fifth metacarpal and metatarsal. Ligaments attach bone to bone or bone to tendon, and are vital in stabilizing joints as well as supporting structures. They are made up of fibrous material that

4209-431: The skin and hair shows both to be unpigmented, and most hair follicles are inactive and many are devoid of hair altogether. All LWS foals test homozygous for a genetic abnormality. Genetic conditions which affect more than one physical trait—in the case of lethal white syndrome, both pigment cells and enteric nerve cells —are termed pleiotropic . The unusual instance of pleiotropy in LWS foals suggested early on that

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4278-434: The sternal flexure, between right and left ventral colon; the pelvic flexure, between left ventral and left dorsal colon; the diaphragmatic flexure, between left dorsal and right dorsal colon. Besides the transverse colon , these sections are all analogous to the ascending colon in humans. The large colon continues the fermentation process, and absorbs volatile fatty acids as an energy source. Due to its many twists and turns,

4347-428: The stomach. A muscular ring, called the cardiac sphincter, connects the stomach to the esophagus. This sphincter is very well developed in horses. This and the oblique angle at which the esophagus connects to the stomach explains why horses cannot vomit . The esophagus is also the area of the digestive tract where horses may suffer from choke . Horses have a relatively small stomach for their size, and this limits

4416-430: The syndrome was related to an important section of embryonic tissue called the neural crest . As the name suggests, the stem cells of the neural crest are precursors to nerve cells . Another cell type that descends from neural crest cells are melanocytes , pigment-producing cells found in hair follicles and skin. The migration of nerve- and melanocyte-precursors from the top of the embryo to their eventual destinations

4485-453: The tendon decreases the overall elasticity in the damaged section of the tendon as well, causing an increase in strain on adjacent uninjured tissue. When a muscle contracts, it pulls a tendon, which acts on the horse's bones to move them. Muscles are commonly arranged in pairs so that they oppose each other (they are "antagonists"), with one flexing the joint (a flexor muscle) and the other extending it (extensor muscle). Therefore, one muscle of

4554-410: The tendon grows. As tendons develop they lay down collagen , which is the main structural protein of connective tissue. As tendons pass near bony prominences, they are protected by a fluid filled synovial structure, either a tendon sheath or a sac called a bursa . Tendons are easily damaged if placed under too much strain, which can result in a painful, and possibly career-ending, injury. Tendinitis

4623-423: The term overo is used to describe a number of other non tobiano spotting patterns besides the frame pattern. Though no treatment or cure for LWS foals is known, a white foal without LWS that appears ill may have a treatable condition. Unlike the premature births and stillborn or weak foals of some coat color dilution lethals , foals born with lethal white syndrome appear to be fully formed and normal. The coat

4692-502: The term "overo". To be categorized as "overo" by the APHA, a horse must fit a written description: white spotting does not cross the back, at least one solid-colored leg, solid tail, face markings, and irregular, scattered, or splashy white patches. To further complicate matters, various Sabino patterns also appear in some horse breeds that do not carry genetics for frame or any other spotting pattern. Likewise, official classification of

4761-462: The title LWS . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=LWS&oldid=1227824305 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Lethal white syndrome The disease has

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