When the seat of dilatation is in the cervical portion of the œsophagus, there are other symptoms which leave no doubt as to the condition. When empty the pouch cannot be detected; but during a meal the accumulation of food causes it to assume the appearance of a doughy, diffuse, indolent swelling, which alters the outline of the jugular furrow, yields to pressure, and sometimes produces respiratory disturbance by pressing on the trachea, the pneumo-gastric and inferior laryngeal nerves, etc. When the dilatation is intra-thoracic and the above-described symptoms have been observed, the dilated spot can only be detected and localised by using the probang. The greatest possible prudence, however, is required in manipulating the instrument, in order to avoid rupturing the thin walls of the dilated portion. =The diagnosis= is not always easy; when food is regurgitated, and one finds by auscultation that the sound usually produced by the passage of solids or liquids into the rumen is absent, there need be no hesitation in diagnosing either a dilatation or a stricture. The clinical consequences being the same, the possible error would be of little importance. =Prognosis.= The animal’s life is rarely in immediate danger, but from the economic point of view the prognosis is extremely grave, and it is in the owner’s interest to slaughter the animal as soon as possible in order to avoid loss. Even in cases of dilatation in the cervical region, surgical interference is not advisable. =Treatment.= As foreshadowed by what has been said, there is no rational economic treatment. When the dilatation is in the cervical region, one might in exceptional cases attempt to restore the regular calibre of the œsophagus by removing an elliptical portion of mucous membrane, and bringing the muscular tissue together with sutures; that is to say, when the rupture or fissuring of the muscular coat has been accidental. But as one is usually unable to remove the primary cause, to which the change in the muscular tissue is essentially due, the dilatation would recur without the operation having conferred any benefit. When an exact diagnosis has been made, the only useful indication is to confine the animal to very fluid food, which will not obstruct the œsophagus. Ordinary forage should be withheld. ŒSOPHAGEAL OBSTRUCTIONS. In this chapter we shall only consider such obstructions as occur in consequence of the animal having attempted to swallow without sufficiently chewing objects which become arrested in the œsophagus.