242 BOVINE PATHOLOGY. 



obstruction in tlie ox, indeed this is natural, for food is 

 taken in hastily and thoroughly mixed with the saliva only 

 when it gains the rumen. Accumulation of food material 

 in a dilated oesophagus and spasm of the muscular coat 

 are occasional causes. Stricture is very liable to cause 

 impediment even when pellets are passing up from the 

 rumen for remastication. Sometimes " hair-balls '' thus 

 cause choking.^ 



Treatment. — When we have reason to suspect pharyn- 

 geal impaction we must have the animal's mouth kept 

 open by means of an ordinary balling iron, and pass the 

 hand through the mouth to explore the pharynx. Some- 

 times it will assist us if an assistant presses the throat on 

 each side behind the maxillary angle inwards and upwards. 

 In the cervical region the tumour may be manipulated, 

 and attempts made to move it upwards or downwards. 

 These may be aided by passing a small quantity of oil 

 into the oesophagus. Sometimes manipulation will disin- 

 tegrate a mass, which will then slowly disappear. Any 

 movement of the body is a favorable sign. If this method 

 fail, the probang, well oiled, may be passed, and gentle 

 but continuous pressure exerted upon the impediment, 

 which may often be felt gradually yielding and passing 

 onward into the stomach. In less favorable cases it will 

 not yield. This frequently depends upon spasm of the 

 oesophagus behind it, and consequently persistence in 

 passing the probang at intervals and applying gentle 

 pressure may be crowned with success. Some practitioners 

 recommend morphia and aconite doses to allay the spasm. 

 Carters' whips, ropes, and other rough instruments are some- 

 times used instead of the probang ; this is reprehensible. 

 Probangs are of various kinds. They almost all consist of 

 an elastic tube, kept open by a spiral wire, and perforated 

 by a central free stilette. One extremity is arranged like a 

 mouth-piece, the other has a bulb, which is sometimes Qgg- 



* Cases of chronic choking are sometimes seen in which a portion of turnip 

 or other substance, of a triangular or irregular shape, becomes fixed in the 

 oesophagus, and allows passage of food downwards. This generally takes 

 place near the stomach. A case has been known to last for six weeks. 



