In this study four ruminant species of Nuremberg Zoo were evaluated for subacute ruminal acidosis according to the feeding management. Parameters of microbiological fermentation of the rumen as well as rumen tissue samples were examined. Additionally, investigations on claw health, in terms of laminitis were made. Three of the four species, all grass- and roughage feeders, showed severe characteristics of subacute ruminal acidosis due to a diet high in fermentable carbohydrates and low in fibre. One species, classified as intermediate feeder, appeared to tolerate the diet with this high concentrate rate, since no pathological variations were present. These results demonstrated that subacute ruminal acidosis is still a serious problem in captive wild ruminants, which are often fed wrong diets with a high concentration of easily digestible carbohydrates.