146 DISEASES OF THE (ESOPHAGUS. 



Here we shall only study the ordinary forms of cesophagitis, leaving 

 on one side those which occur symptomatically during foot-and-mouth 

 disease, cattle plague, gangrenous coryza, actinomycosis, etc. 



Causation. The causes of oesophagitis may be divided into three 

 groups of different character: — (a) Eough fodder (clover containing wrest- 

 harrow, thistles, thorns, furze, or splinters of wood, etc.) must be placed 

 in the first rank, for its repeated action abrades and irritates the mucous 

 membrane to such an extent as finally to produce inflammation. This 

 inflammation usually remains superficial and of moderate intensity ; its 

 occurrence can be anticipated during years of scarcity, when the animals 

 feed on rough and irritating material like fern, broom, heather, furze, etc. 



(h) Hot drinks, whether in the nature of beverages or medicinal 

 draughts, are a frequent cause of oesophagitis if administered by careless 

 or inexperienced persons. The mucous membrane is scalded over a 

 varying area and with different degrees of severity, or is destroyed 

 by the chemical action of such drugs as ammonia, dilute acids, iodine 

 solution, etc. 



(c) Eough or clumsy manipulation in withdrawing or displacing 

 foreign bodies, or merely passing the probang, produces that variety of 

 oesophagitis termed traumatic. In clumsy hands oesophageal sounds or 

 catheters may abrade or even tear the mucous membrane and subjacent 

 tissues. 



Symptoms. These vary to some extent, according to the intensity 

 of the inflammatory phenomena. If the lesions are superficial and only 

 implicate the epithelium, as in catarrhal oesophagitis, the symptoms often 

 pass unnoticed, and only produce difficulty in swallowing. When inflam- 

 mation has involved the entire thickness of the mucous membrane the 

 immediate consequence is loss of appetite due to pain during swallowing. 

 After the bolus of food has been masticated, and has passed into the 

 pharynx, the animal stretches out its head and neck and seems to be 

 making efforts to force it down the oesophageal canal. The progress of 

 the bolus is slow and clearly difficult. 



In oesophagitis due to scalding the blisters are soon broken by the 

 passage of food, the corium is exposed, and the animal has equal difficulty 

 in swallowing either solids or liquids. The reflex action provoked by the 

 passage of the food over these lesions may be so violent that the ingesta 

 never arrive at the stomach, but are violently rejected by a sudden and 

 unexpected antiperistaltic contraction. Even saliva is returned. More- 

 over, in these cases the history is generally clear, and the animal is 

 feverish or greatly depressed. These objective symptoms are very 

 significant, and when, in addition, an abnormal and exceptional degree 

 of sensibility is detected at some point by palpation, they unmistakably 

 indicate the existence of oesophagitis. 



