Changes

*'''Gastrodudodenal motility''': critically ill neonatal foals can have a substantially different pH profile compared to clinically normal foals, possibly due to changes in gastric motility and acid secretion.<ref>Sanchez, L.C, Lester, G.D, Merritt, A.M (2001) Intragastric pH in critically ill neonatal foals and the effect of ranitidine.  ''J Am Vet Med Assoc'', 218:907-911.  In: Sanchez, L.C (2010) 'Diseases Of The Stomach' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), Saunders, Chapter 15.</ref>

*'''Gastrodudodenal motility''': critically ill neonatal foals can have a substantially different pH profile compared to clinically normal foals, possibly due to changes in gastric motility and acid secretion.<ref>Sanchez, L.C, Lester, G.D, Merritt, A.M (2001) Intragastric pH in critically ill neonatal foals and the effect of ranitidine.  ''J Am Vet Med Assoc'', 218:907-911.  In: Sanchez, L.C (2010) 'Diseases Of The Stomach' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), Saunders, Chapter 15.</ref>

====Intrinsic ulcerogenic factors====

====Intrinsic ulcerogenic factors<ref name="Nadeau">Nadeau, J.A, Andrews, F.M (2009) ''Science: Overviews'' Equine gastric ulcer syndrome: The continuing conundrum.  ''Equine Vet J'', 41(7):611-615.</ref>====

Hydrochloric acid (HCl) and a sustained gastric pH<4.0 are the most significant factors in gastric ulceration.  Volatile fatty acids (VFAs), lactic acid and bile acids act synergistically with HCl to cause changes in squamous mucosal bioelectric properties (the first sign of acidic damage).  VFAs and lactic acid are by-products of bacterial fermentation of sugars in concentrate diets.

Hydrochloric acid (HCl) and a sustained gastric pH<4.0 are the most significant factors in gastric ulceration.  Volatile fatty acids (VFAs), lactic acid and bile acids act synergistically with HCl to cause changes in squamous mucosal bioelectric properties (the first sign of acidic damage).  VFAs and lactic acid are by-products of bacterial fermentation of sugars in concentrate diets.

*'''Hydrochloric acid''' damages the squamous mucosa by compromising the outer cell barrier.  It then diffuses into the squamous cells of the ''stratum spinosum'', inhibiting cellular sodium transport and causing cell swelling, necrosis and eventual ulceration.<ref>Nadeau, J.A, Andrews, F.M, Patton, C.S, Argenzio, R.A, Mathew, A.G, Saxton, A.M (2003) Effects of hydrochloric, acetic, butyric, and proprionic acids on pathogenesis of ulcers in the nonglandular portion of the stomach of horses.  ''Am J Vet Res'',64:404-412.</ref><ref>Ndeau, J.A, Andrews, F.M, Patton, C.S, Argenzio, R.A, Mathew, A.G, Saxton, A.M (2003) Effects of hydrochloric, valeric, and other volatile fatty acids on pathogenesis of ulcers in the nonglandular portion of the stomach of horses.  ''Am J Vet Res'', 64:413-417.</ref>

*'''Hydrochloric acid''' damages the squamous mucosa by compromising the outer cell barrier.  It then diffuses into the squamous cells of the ''stratum spinosum'', inhibiting cellular sodium transport and causing cell swelling, necrosis and eventual ulceration.<ref>Nadeau, J.A, Andrews, F.M, Patton, C.S, Argenzio, R.A, Mathew, A.G, Saxton, A.M (2003) Effects of hydrochloric, acetic, butyric, and proprionic acids on pathogenesis of ulcers in the nonglandular portion of the stomach of horses.  ''Am J Vet Res'',64:404-412.</ref><ref>Nadeau, J.A, Andrews, F.M, Patton, C.S, Argenzio, R.A, Mathew, A.G, Saxton, A.M (2003) Effects of hydrochloric, valeric, and other volatile fatty acids on pathogenesis of ulcers in the nonglandular portion of the stomach of horses.  ''Am J Vet Res'', 64:413-417.</ref>

====Extrinsic ulcerogenic factors====

====Extrinsic ulcerogenic factors====