Table 8.

ABMs of gastroenteric (GE) disorders in calves kept in individual housing

ABM	Comments
Diarrhoea	Definition: Stool on the floor or on the bedding material. Character and colour of the faeces vary but are usually voluminous, watery or very loose, white, yellow or greenish. Watery faeces may also cover the tail, perineum and hind legs (Van Metre et al., 2008). Sensitivity: High. Specificity: High.
Hair loss in the perineum and hind legs	Definition: Small to extensive areas without any hair are seen where diarrhoea caused the death of hair follicles (Van Metre et al., 2008). Sensitivity: Low. Not all calves experiencing GE disorders will show hair loss in the perineum and hind legs. Specificity: High.
Mortality > 1%	Definition: Mortality due to Neonatal Diarrhoea above 1% of all calves born alive, should trigger careful investigation (Van Metre et al., 2008). Sensitivity: Low. Farms with GE problems may have low mortality due to good disease management. Specificity: Low. Mortality can also be due to other problems (e.g. respiratory disorders).
Bloat	Definition: A calf with an obvious distended and tensed belly, more convex than the shape of the ribs (Panciera et al., 2007; Marshall, 2009). Sensitivity: High. Specificity: Low. There are other causes for bloat that are not related to ruminal drinking (e.g. chronic respiratory disease).