Changes

==Prevalence==

==Prevalence==

The prevalence of equine gastric ulceration has increased over the last century (Sandin et al 2000 in Martineau 2009). Lesions are most often found in the squamous mucosa along the margo plicatus, then the glandular body, proximal squamous mucosa and antrum (17 in Sanchez).  For the squamous region, reported prevalences are:

The prevalence of equine gastric ulceration has increased over the last century.<ref>Sandin, A, Skidell, J, Haggstrom, J, Nilsson, G (2000) ''Postmortem'' findings of gastric ulcers in Swedish horses older than age one year: a retrospective study of 3715 horses (1924–1996).  ''Equine Vet J'', 32(1):36-42.</ref> Lesions are most often found in the squamous mucosa along the margo plicatus, then the glandular body, proximal squamous mucosa and antrum (17 in Sanchez).  For the squamous region, reported prevalences are:

Racehorses 70-100% (Hammond et al 1986, Vatistas et al 1994 and 1997, Murray et al 1996) (3-11 in Sanchez)

*Racehorses 70-100% (Hammond et al 1986, Vatistas et al 1994 and 1997, Murray et al 1996) (3-11 in Sanchez)

Racehorses in active race training 80-90% (incidence 100%) (Vatistas 2 1999)

*Racehorses in active race training 80-90% (incidence 100%) (Vatistas 2 1999)

Show horses 58% (McClure et al 1999) (12 in Sanchez)

*Show horses 58% (McClure et al 1999) (12 in Sanchez)

Ponies 78% (MacAllister et al 1982)

*Ponies 78% (MacAllister et al 1982)

Endurance 67% (Pieto et al 2004) (13 in Sanchez)

*Endurance 67% (Pieto et al 2004) (13 in Sanchez)

Western performance horses 40 % (14 in Sanchez)

*Western performance horses 40 % (14 in Sanchez)

Thoroughbred broodmares (67-77%) (15 in Sanchez) (LeJeune, S.S, Nieto, J.E, Dechant, J.E, Snyder, J.R (2009) Prevalence of gastric ulcers in Thoroughbred broodmares in pasture: a preliminary report.  Vet J, 181(3):251-5.

*Thoroughbred broodmares (67-77%) (15 in Sanchez) (LeJeune, S.S, Nieto, J.E, Dechant, J.E, Snyder, J.R (2009) Prevalence of gastric ulcers in Thoroughbred broodmares in pasture: a preliminary report.  Vet J, 181(3):251-5.

Nonracing performance horses (17 % precompetition, 56% postcompetition)

*Nonracing performance horses (17 % precompetition, 56% postcompetition)

Pleasure horses in full work ~ 60% (Bell, R.J, Mogg, T., Kingston, J.K (2007) and impact upon welfare (Martineau 2009). Equine gastric ulcer syndrome in adult horses: a review.  N Z Vet J, 55(1):1-12).   

*Pleasure horses in full work ~ 60% (Bell, R.J, Mogg, T., Kingston, J.K (2007)  Equine gastric ulcer syndrome in adult horses: a review.  N Z Vet J, 55(1):1-12).   

Pleasure, riding lessons, showing 37 % (Murray et al 1989 in Orsini)

*Pleasure, riding lessons, showing 37 % (Murray et al 1989 in Orsini)

Foals – 25-57% (20-22 in Sanchez) unknown, probably common, increasing or diagnosing more? Overall, the currently accepted prevalence estimates is 30-50%, increasing sharply in foals demonstrating signs of disease, especially gastrointestinal signs.(EGUC)

*Foals – 25-57% (20-22 in Sanchez) unknown, probably common, increasing or diagnosing more? Overall, the currently accepted prevalence estimates is 30-50%, increasing sharply in foals demonstrating signs of disease, especially gastrointestinal signs.<ref name="EGUC">The Equine Gastric Ulcer Council (1999) Tutorial Article: Recommendations for the diagnosis and treatment of equine gastric ulcer syndrome (EGUS).  ''Equine Vet Educ'', 11(5):262-272.</ref>

The prevalence and severity of ulcers increases with work intensity(Merck) and duration(Murray 1994; Orsini and Pipers 1997 in Orsini),  thus racehorses in active training are more often affected (Hammond et al. 1986; Johnson et al. 1994) and in half of these,  the lesions are moderate to severe (Merck). In one study, all horses developed gastric ulcers within 2 weeks of entering simulated race training. (Vatistas 2 1999).  Lesions are thought to be chronically progressive during race training, but to regress during retirement.(Hammond 1986). Horses with signs of gastrointestinal distress also demonstrate an increased frequency and severity of ulcerative lesions.(EGUC)Among show horses, 82% of those with signs of abdominal discomfort had gastric ulcers (Murray 1992a).(Martineau 2009) .  Around 30% of adult horses and about 50% of foals have mild gastric erosions which heal without treatment or clinical signs(Merck).   In 201 clinically normal horses in Denmark, 53% had EGUS with severity score >2 and older horses were more likely to have lesions in both regions of the stomach (Luthersson, N, Nielsen, K.H, Harris, P, Parkin, T.D (2009) The prevalence and anatomical distribution of equine gastric ulcer syndrome (EGUS) in 201 horses in Denmark.  Equine Vet J, 41(7):619-24.

The prevalence and severity of ulcers increases with work intensity<ref name="Merck">Merck & Co (2008) The Merck Veterinary Manual (Eighth Edition), Merial</ref> and duration(Murray 1994; Orsini and Pipers 1997 in Orsini),  thus racehorses in active training are more often affected (Hammond et al. 1986; Johnson et al. 1994) and in half of these,  the lesions are moderate to severe.<ref name="Merck">Merck & Co (2008) The Merck Veterinary Manual (Eighth Edition), Merial</ref> In one study, all horses developed gastric ulcers within 2 weeks of entering simulated race training. (Vatistas 2 1999).  Lesions are thought to be chronically progressive during race training, but to regress during retirement.(Hammond 1986). Horses with signs of gastrointestinal distress also demonstrate an increased frequency and severity of ulcerative lesions.(EGUC)Among show horses, 82% of those with signs of abdominal discomfort had gastric ulcers (Murray 1992a).<ref name="Martineau">Martineau, H, Thompson, H, Taylor, D (2009) Pathology of gastritis and gastric ulceration in the horse.  Part 1: Range of lesions present in 21 mature individuals.  ''Equine Vet J'', 41(7):638-644.</ref>   Around 30% of adult horses and about 50% of foals have mild gastric erosions which heal without treatment or clinical signs.<ref name="Merck">Merck & Co (2008) The Merck Veterinary Manual (Eighth Edition), Merial</ref>   In 201 clinically normal horses in Denmark, 53% had EGUS with severity score >2 and older horses were more likely to have lesions in both regions of the stomach (Luthersson, N, Nielsen, K.H, Harris, P, Parkin, T.D (2009) The prevalence and anatomical distribution of equine gastric ulcer syndrome (EGUS) in 201 horses in Denmark.  Equine Vet J, 41(7):619-24.