Images were submitted of lamb rumens that, once washed and scalded, remained dirty, with partial or complete, dark adhesions of the mucosa on the inside.

This brown coloration is due to a hyperkeratosis of the ruminal mucosa that appears due to diets low in fiber, that is, rich in carbohydrates. If these are in too high a proportion, ruminal acidosis is generated, then the rumen wall becomes inflamed and the mucosa remains adhered.

On the left of a normal lamb stomach after its washing and scalding, to the right two stomachs with varying degrees of adhesion of the mucosa.