Changes

====Intrinsic ulcerogenic factors====

====Intrinsic ulcerogenic factors====

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. (Argenzio and Eismann 1987; Nadeau et al. 2003a,b)

*'''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>

*'''Volatile Fatty Acids (VFAs)''' (acetic, propionic, butyric and valeric acids) are lipid soluble.  They readily diffuse into the squamous mucosal cells of the ''stratum spinosum'' causing similar damage to HCl.

*'''Lactic acid''' may play a role in increasing the permeability of the squamous mucosa.<ref>Andrfews, F.M, Buchanan, B.R, Elliott, S.B, Al Jassim, R.A.M, McGowan, C.M, Saxton, A.M (2008) ''In vitro'' effects of hydrochloric and lactic acids on bioelectric properties ofequine gastric squamous mucosa.  ''Equine Vet J'', 40:301-305.</ref>

====Extrinsic ulcerogenic factors====

====Extrinsic ulcerogenic factors====