Changes

====Extrinsic ulcerogenic factors (RISK FACTORS)====

====Extrinsic ulcerogenic factors (RISK FACTORS)====

*'''Exercise:''' there appears to be a high prevalence of gastric ulcers in horses performing in most disciplines.<ref>Hartmann, A.M, Frankeny, R.L (2003) A preliminary investigation into the association between competition and gastric ulcer formation in non-racing performance horses.  ''J Equine Vet Sci'', 23:560-561.  In: Nadeau, J.A, Andrews, F.M (2009) ''Science: Overviews'' Equine gastric ulcer syndrome: The continuing conundrum.  ''Equine Vet J'', 41(7):611-615.</ref>  Although this may be related to exercise, other confounding factors related to these disciplines such as travel, diet, feeding regime, use of non-steroidal anti-inflammatories (NSAIDs) and stress may be significant.  However, Vatistas and co-workers (1999) were able to induce and maintain EGUS in racehorses in fast work without the use of NSAIDs or fasting before exercise.<ref name="Vatistas 2">Vatistas, N.J, Sifferman, R.L, Holste, J, Cox, J.L, Pinalto, G, Schultz, K.T (1999) Induction and maintenance of gastric ulceration in horses in simulated race training.  ''Equine Vet J Suppl'', 29:40-44</ref>  There is also evidence that training for just 8 days is suffcient to induce gastric ulcers.<ref>White, G, McClure, S.R, Siifferman, R, Holste, J.E, Fleishman, C, Murray, M.J, Cramer, L.G (2007) Effects of short-term light to heavy exercise on gastric ulcer development in horses and efficacy of omeprazole paste in preventing gastric ulceration.  ''J Am Vet Med Assoc'', 230(11):1680-2.</ref>  The higher prevalence of gastric ulcers at ''post mortem'' in racehorses in training compared to those in retirement is consistent with the hypothesis that exercise may be an important risk factor for EGUS.<ref name="Hammond">Hammond, C.J, Mason, D.K, Watkins, K.L (1986) Gastric ulceration in mature Thoroughbred horses.  ''Equine Vet J'', 18(4):284-287.</ref>  Strenuous exercise is known to stimulate gastrin release which has effects on HCl secretion, gastric emptying and gastric blood flow.  Diversion of blood to active muscle groups may further deprive the gastric mucosa of the perfusion required for its integrity(REF).  It is also thought that exposure of the squamous mucosa to acid is increased as the stomach is compressed by the abdominal viscera and diaphragm during excercise.<ref>Lorenzo-Figueras, M, Merritt, A.M (2002) Effects of exercise on gastric volume and pH in the proximal portion of the stomach of horses.  ''Am J Vet Res'', 63:1481-1487.</ref>

*'''Exercise:''' there appears to be a high prevalence of gastric ulcers in horses performing in most disciplines.<ref>Hartmann, A.M, Frankeny, R.L (2003) A preliminary investigation into the association between competition and gastric ulcer formation in non-racing performance horses.  ''J Equine Vet Sci'', 23:560-561.  In: Nadeau, J.A, Andrews, F.M (2009) ''Science: Overviews'' Equine gastric ulcer syndrome: The continuing conundrum.  ''Equine Vet J'', 41(7):611-615.</ref>  Although this may be related to exercise, other confounding factors related to these disciplines such as travel, diet, feeding regime, use of non-steroidal anti-inflammatories (NSAIDs) and stress may be significant.  However, Vatistas and co-workers (1999) were able to induce and maintain EGUS in racehorses in fast work without the use of NSAIDs or fasting before exercise.<ref name="Vatistas 2">Vatistas, N.J, Sifferman, R.L, Holste, J, Cox, J.L, Pinalto, G, Schultz, K.T (1999) Induction and maintenance of gastric ulceration in horses in simulated race training.  ''Equine Vet J Suppl'', 29:40-44</ref>  There is also evidence that training for just 8 days is suffcient to induce gastric ulcers.<ref>White, G, McClure, S.R, Siifferman, R, Holste, J.E, Fleishman, C, Murray, M.J, Cramer, L.G (2007) Effects of short-term light to heavy exercise on gastric ulcer development in horses and efficacy of omeprazole paste in preventing gastric ulceration.  ''J Am Vet Med Assoc'', 230(11):1680-2.</ref>  The higher prevalence of gastric ulcers at ''post mortem'' in racehorses in training compared to those in retirement is consistent with the hypothesis that exercise may be an important risk factor for EGUS.<ref name="Hammond">Hammond, C.J, Mason, D.K, Watkins, K.L (1986) Gastric ulceration in mature Thoroughbred horses.  ''Equine Vet J'', 18(4):284-287.</ref>  Strenuous exercise is known to stimulate '''gastrin release''' which has effects on HCl secretion, gastric emptying and gastric blood flow.  Diversion of blood to active muscle groups may further deprive the gastric mucosa of the perfusion required for its integrity(REF).  It is also thought that exposure of the squamous mucosa to acid is increased as the stomach is compressed by the abdominal viscera and diaphragm during excercise.<ref>Lorenzo-Figueras, M, Merritt, A.M (2002) Effects of exercise on gastric volume and pH in the proximal portion of the stomach of horses.  ''Am J Vet Res'', 63:1481-1487.</ref>

*'''Housing and Transport:'''  housing in '''stables''' has been proposed as a risk factor for gastric ulcers, with more lesions being found in confined horses compared to those out at grass.<ref>Murray, M.J, Eichorn, E.S (1996) Effects of intermittent feed deprivation, intermittent feed deprivation with ranitidine administration, and stall

*'''Housing and Transport:'''  housing in '''stables''' has been proposed as a risk factor for gastric ulcers, with more lesions being found in confined horses compared to those out at grass.<ref>Murray, M.J, Eichorn, E.S (1996) Effects of intermittent feed deprivation, intermittent feed deprivation with ranitidine administration, and stall