In spite of treatment, or in consequence of treatment being too long delayed, no improvement may follow. The ingested food is not expelled. Putrid fermentation results, auto-intoxication sets in, and the temperature rises to 40° or 41° C. Unless gastrotomy is performed death is then certain. This operation should be undertaken whenever the fever rises to 40° C., and two-thirds of the contents of the rumen removed. The rumen should not be completely emptied, as there is danger of collapse of its walls. Complications in the region of the wound can be avoided by drainage. If the operation succeeds, the patients must be placed on very low diet or on milk for some days, and should be given lukewarm farinaceous drinks, and a little hay of good quality to excite rumination. In old milch cows this operation is seldom followed by a satisfactory recovery. Apart from the loss of milk, the animal loses condition, refuses to feed, and gradually succumbs to exhaustion. IMPACTION OF THE OMASUM (THIRD STOMACH). =Definition.= “A form of indigestion, of which the prominent feature is the drying and impaction of the ingesta between the folds of the third stomach. It may seem to be a primary disease, but in very many cases it occurs as a result of some acute febrile or inflammatory affection.” (Law’s “Veterinary Medicine,” Vol. II. p. 123.) =Synonyms.= Dry murrain, clew-bound, fardel-bound, stomach staggers, grass staggers, vertigo, chronic dyspepsia, chronic indigestion. =Causes.= Torpidity of the omasum, suppression of salivary secretion, with absence of “waves of liquid floating the finely divided food from the mouth or rumen to third stomach, are prime conditions of desiccation of the contents.” The third stomach, like the first and second, has no provision for liquid secretion, and depends for its supply on constant flushing by swallowed fluids. Therefore, if feeding and rumination are arrested and salivary secretion is suppressed, and if movements of the rumen and resulting overflow into the third stomach are checked, the ingesta of the third stomach, compressed between its folds, becomes drained of liquid and converted into a powder or dry mass. All febrile and inflammatory affections tend to this end, and more or less drying, with impaction of the contents of the omasum, is a constant feature in such cases. But in the majority of cases this condition is to be looked on as a secondary or subsidiary affection, and the real disease must be sought elsewhere.