*Blue or purple mucous membranes<ref name="Proudman">Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective. ''Equine Vet Educ'', 6(4):178-184.</ref> | *Blue or purple mucous membranes<ref name="Proudman">Proudman, C.J, Baker, S.J (1994) Satellite Article: Gastric disease in the adult horse: a clinical perspective. ''Equine Vet Educ'', 6(4):178-184.</ref> |