Clinical findings and examination of feeding history and feed should raise suspicions. Bubbly diarrhoea can indicate acidosis, as it is a sign that feed is passing through undigested and there is fermentation occurring in the faeces.
Clinical findings and examination of feeding history and feed should raise suspicions.
Mild acidosis is associated with watery faeces accompanied by temporary inappetence. Increasing severity is evident by depression, dehydration, absence of ruminal movements, weak pulse, slow capillary refill, subnormal temperature, diarrhoea, and colic. Some animals may later develop laminitis or liver abscess.
Animals that survive the acute illness may still die within days due to kidney failure, fungal rumenitis or peritonitis.
At necropsy, the rumen is distended with pellets and fluid. Note that sloughing of the rumen mucosa is a normal post-mortem change occurring within an hour of death and should not be regarded as evidence of rumenitis or excessive grain feeding unless associated with inflammatory change.
Urine test strips or specific test strips may be used to test pH of rumen fluid. Normal rumen pH is >5.9 and acidosis should be suspected if the pH is less than 5.5.
Rumen pH can change in the hours after death as rumen fermentation continues, so samples not taken close to the time of death must be interpreted with caution.
Laboratory confirmation requires sections of reticulum and ventral rumen in buffered formalin for histology.
Differential diagnoses include salmonellosis, gastrointestinal accidents, enterotoxaemia, and bloat.