In this condition the rumen is over-distended with food. The symptoms are principally due to abnormal fermentation, the peristaltic action of the rumen being in abeyance, and the food failing to pass towards the omasum and abomasum. Rumination is generally suppressed. The disease usually follows change of diet. When the diet has long been restricted, as occurs during years of bad harvests, and animals are afterwards set at liberty in rich pastures, they eat greedily, distend the rumen with large quantities of green fodder, and set up all the necessary conditions for this form of indigestion. Similar results follow when gluttonous animals are freely supplied with rich food. Working oxen also suffer if withdrawn from work and fed with roots, beetroot refuse, brewers’ grains, or other manufacturing residue for the purpose of fattening. These materials can only be absorbed in moderate quantity, and the large amount of water, etc., they contain is apt to disturb the animal’s digestive powers, while owing to its fine state of division such food cannot be returned to the mouth for secondary mastication, and rumination therefore remains incomplete: the food accumulates in the rumen, distending and eventually paralysing it. This is a common result of feeding on semi-liquid pulp, which in order to be ruminated should be mixed with rough forage. Insufficiency of drinking water is another and more frequent cause, especially during the winter, because the ox-herd or cowman is often too lazy to give a regular and sufficient supply unless water is laid on in the stable itself. The dry food becomes compacted into a mass, which cannot be returned to the mouth for rumination. Moreover, less saliva is then secreted, and Colin has shown that rumination is impossible when the parotid ducts are ligatured. =Symptoms.= As may readily be imagined, the symptoms vary, according to the quantity and digestibility of the food swallowed. In the first place the appetite falls off: animals suffering from commencing indigestion only take part of their food; later on appetite ceases, and with it rumination. Trifling colic sets in, resembling that due to congestion, and is indicated by unrest, switching of the tail, lifting of the hind legs, slight groaning, moving from side to side, and lying down and rising at short intervals. The animals seem oblivious of their surroundings, anxious, and at times semi-comatose.