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This page is a workshop for the Health Issues section on the Thoroughbred page. Deletions have been made with strikeout, and my additions are in red, using: <span style="color:red"></span>. New references have been added, but I don't know how to get them to stand out...

I put my strikeouts in green Ealdgyth - Talk 15:51, 24 April 2008 (UTC)

There is a 'clean' section below with Ealdgyth's edits incorporated.Getwood (talk) 01:31, 25 April 2008 (UTC)

Contents 1 Health Issues 1.1 Selective breeding theory 1.2 Excess stress theory 1.3 Difficulties treating injured horsesMedical challenges 2 Notes 3 Clean version as of Getwood (talk) 01:31, 25 April 2008 (UTC) 3.1 Health Issues 3.1.1 Selective breeding 3.1.2 Excess stress 3.1.3 Medical challenges 3.2 Notes

[edit] Health Issues

Although Thoroughbreds are seen in the hunter-jumper world and other purposes, modern Thoroughbreds are primarily bred for speed and racehorses have a very high rate of accidents plus as well as other health problems. This has created a number of concerns and significant controversies.

One tenth of all Thoroughbreds suffer various orthopedic problems, including fractures.^[1] Current estimates indicate that there are 1.5 career-ending breakdowns for every 1000 horses starting a race in the United States, an average of two horses per day. The state of California reported a particularly high rate of injury; 3.5 per 1000 starts.^[2] As a ratio (of injuries with eventually fatal complications to total competitions), this is far in excess of all other legal human and animal sports, including boxing, motorsports and greyhound racing.^[3] Thoroughbreds also have other health concerns, including a majority of animals who are prone to bleeding from the lungs (EIPH), 10% with low fertility, and 5% that havewith abnormally small hearts.^[1] Thoroughbreds also tend to have smaller hooves relative to their body mass than other breeds, with thin soles and walls and a lack of cartilage mass.,^[4] which contributes to foot soreness, the most common source of lameness in racehorses.^[5]

[edit] Selective breeding theory

One argument for the difficulties that plague health issues involving Thoroughbreds suggests that inbreeding is the culprit.^[1] It has also been suggested that capability for speed is enhanced in an already swift animal by raising muscle mass, a form of selective breeding that has created animals designed to win horse races.^[6] Thus, goes the theory, the modern Thoroughbred travels faster than its skeletal structure can support. ^[7] As a result, all competitive modern Thoroughbreds are muscularly powerful yet osteologically delicate creatures, significantly more so than any equid, fossil or living, found in the wild. "We have selectively bred for speeds that the anatomy of the horse cannot always cope with."^[8]

[edit] Excess stress theory

The high accident rate may also occur because Thoroughbreds, particularly in the United States, are first raced as 2-year-olds, well before they are completely mature. Though they may appear full-grown and are in superb muscular condition, their bones are not fully formed.^[8] However, catastrophic injury rates are higher in 4 and 5-year-olds than in 2 and 3-year-olds.^[9]Other theories suggest Studies have shown that track surfaces,^[10] horseshoes with toe grabs,^[4] use of certain legal medications,^[11] and too intense a racing schedule may also contribute.^[12] One of the most promising trends is the development of synthetic surfaces for racetracks. One of the first tracks to install such a surface, Turfway Park in Florence, Kentucky, saw its rate of fatal breakdowns drop from 24 in 2004-2005 to three in the year following Polytrack installation. The material is not perfected, with some areas reporting problems related to winter weather, but studies are continuing.^[2]

[edit] Difficulties treating injured horsesMedical challenges

The level of treatment given to injured Thoroughbreds is often more intensive than for horses of lesser financial value,^[13] but also controversial, due in part to the significant challenges in treating broken bones and other major leg injuries.^[14] Leg injuries that are not immediately fatal still may be life-threatening because a horse's weight must be distributed evenly on all four legs to prevent circulatory problems, laminitis and other infections. If a horse loses the use of one leg temporarily, there is the risk that other legs will break down during the recovery period because they are carrying an abnormal weight load. While horses do periodically lie down for brief periods of time, a horse cannot simply remain lying down in the equivalent of a human's "bed rest" due to the risk of developing sores and internal damage and congestion.^[14]

Whenever a racing accident severely injures a well-known horse, such as the case of Kentucky Derby winner Barbaro breaking his leg during the 2006 Preakness Stakes, animal rights groups tend to target the tThoroughbred racing industry.^[15] On the other side, advocates of racing argue that without horse racing, there would be far less funding and incentives to pursue medical and biomechanical research on horses.^[16] The bioethics are seldom clean-cut. While horse racing is hazardous, veterinary science is also developing, so that previously hopeless cases can now be treated.,^[14] and earlier detection through advanced imaging techniques like scintigraphy can keep at-risk horses off the track.^[17]

[edit] Notes

[edit] Clean version as of Getwood (talk) 01:31, 25 April 2008 (UTC)

[edit] Health Issues

Although Thoroughbreds are seen in the hunter-jumper world and other purposes, modern Thoroughbreds are primarily bred for speed and racehorses have a very high rate of accidents as well as other health problems.

One tenth of all Thoroughbreds suffer orthopedic problems, including fractures.^[1] Current estimates indicate that there are 1.5 career-ending breakdowns for every 1000 horses starting a race in the United States, an average of two horses per day. The state of California reported a particularly high rate of injury; 3.5 per 1000 starts.^[2] As a ratio (of injuries with eventually fatal complications to total competitions), this is far in excess of all other legal human and animal sports, including boxing, motorsports and greyhound racing.^[3] Thoroughbreds also have other health concerns, including a majority of animals who are prone to bleeding from the lungs (EIPH), 10% with low fertility, and 5% with abnormally small hearts.^[1] Thoroughbreds also tend to have smaller hooves relative to their body mass than other breeds, with thin soles and walls and a lack of cartilage mass,^[4] which contributes to foot soreness, the most common source of lameness in racehorses.^[5]

[edit] Selective breeding

One argument for the health issues involving Thoroughbreds suggests that inbreeding is the culprit.^[1] It has also been suggested that capability for speed is enhanced in an already swift animal by raising muscle mass, a form of selective breeding that has created animals designed to win horse races.^[6] Thus, goes the theory, the modern Thoroughbred travels faster than its skeletal structure can support. ^[7] "We have selectively bred for speeds that the anatomy of the horse cannot always cope with."^[8]

[edit] Excess stress

The high accident rate may also occur because Thoroughbreds, particularly in the United States, are first raced as 2-year-olds, well before they are completely mature. Though they may appear full-grown and are in superb muscular condition, their bones are not fully formed.^[8] However, catastrophic injury rates are higher in 4 and 5-year-olds than in 2 and 3-year-olds.^[9] Studies have shown that track surfaces,^[10] horseshoes with toe grabs,^[4] use of certain legal medications,^[11] and too intense a racing schedule may also contribute.^[12] One of the most promising trends is the development of synthetic surfaces for racetracks. One of the first tracks to install such a surface, Turfway Park in Florence, Kentucky, saw its rate of fatal breakdowns drop from 24 in 2004-2005 to three in the year following Polytrack installation. The material is not perfected, with some areas reporting problems related to winter weather, but studies are continuing.^[2]

[edit] Medical challenges

The level of treatment given to injured Thoroughbreds is often more intensive than for horses of lesser financial value,^[13] but also controversial, due in part to the significant challenges in treating broken bones and other major leg injuries.^[14] Leg injuries that are not immediately fatal still may be life-threatening because a horse's weight must be distributed evenly on all four legs to prevent circulatory problems, laminitis and other infections. If a horse loses the use of one leg temporarily, there is the risk that other legs will break down during the recovery period because they are carrying an abnormal weight load. While horses do periodically lie down for brief periods of time, a horse cannot simply remain lying down in the equivalent of a human's "bed rest" due to the risk of developing sores and internal damage and congestion.^[14]

Whenever a racing accident severely injures a well-known horse, such as the case of Kentucky Derby winner Barbaro breaking his leg during the 2006 Preakness Stakes, animal rights groups target the Thoroughbred racing industry.^[15] On the other side, advocates of racing argue that without horse racing, there would be far less funding and incentives to pursue medical and biomechanical research on horses.^[16] While horse racing is hazardous, veterinary science is also developing, so that previously hopeless cases can now be treated,^[14] and earlier detection through advanced imaging techniques like scintigraphy can keep at-risk horses off the track.^[17]

[edit] Notes