Table 11.

ABM of gastroenteric disorders in veal calves kept in small groups. The assessment of abomasal lesions, ruminal plaques and rumen underdevelopment can only be carried post‐mortem at abattoir level

ABM	Comments
Abomasal lesions	Definition: Presence of lesions in the abomasum (torus pylorus, pyloric area), classified according to size and severity (for a description of scoring systems of abomasal lesions, see Section 3.17.4.3). Sensitivity: Low. Not all calves with GE disorders will show abomasal lesions. Specificity: High.
Ruminal plaques	Definition: Presence of plaques (multiple patches with coalescing papillae covered by a sticky mass and hair), hyperkeratosis (hardened rumen papillae) and underdeveloped rumen mucosa (almost no papillae in atrium and ventral and dorsal rumen) (Suárez et al., 2006). Sensitivity: Low. Not all calves with GE disorders will show ruminal plaques. Specificity: High. Ruminal plaques are a specific indicator of low‐quality fibre.
Rumen under‐development	Definition: Small, underdeveloped rumen mucosa with almost no papillae in atrium and ventral and dorsal areas (Suárez et al., 2006; Brščić et al., 2011a,b). Sensitivity: Low. Not all calves with GE disorders will show ruminal plaques. Specificity: High.