SIMPLE PNEUMONIA IN THE HORSE. 



175 



of the cohabitation of an affected patient with other horses of all ages, 

 the latter successfully resist. Many continue to consider contagious 

 pneumonia and simple pneumonia (or pneumonia ^7 frigore) as different 

 affections, chiefly because the latter has not the eminently infectious 

 character of the former ; but also because it generally shows special 

 clinical and anatomical pathological characters. Nevertheless I 

 repeat, that very often when examining a patient it is impossible to 

 decide by the clinical symptoms alone what form of disease we have to 

 deal with, and it is now known that lobar hepatisation is not an ana- 

 tomical character peculiar to pneumonia a frigore. 



Many authors state that a first attack predisposes to a return of the 

 disease. This opinion, founded on the widely accepted belief that after 

 inflammation the lung remains more or less injured and enfeebled, is in 

 no way conflrmed by clinical observation. Not only have I failed to 

 observe this predisposition, but I believe, on the contrary, that a horse 

 which has previously suffered from pneumonia is less exposed to the 

 disease, and that it acquires a certain degree of immunity. I consider 

 that in animals which have made a good recovery from pneumonia we 

 should regard the traces left by blisters, etc., on the chest as an indica- 

 tion of greater resistance, instead of considering them, as many prac- 

 titioners do, as signs of grave depreciation. And when the disease 

 returns in such horses, the second attack is almost always benign in 

 character. 



Simple pneumonia is ushered in by general disturbance, often by 

 rigors, soon followed by gradual rise in temperature. The animals 

 tremble slightly ; the majority are depressed and stiff, the appetite 

 falls off, the mouth is hot and dry, the bowels are constipated ; the 

 conjunctiva is injected, or yellowish in colour, and the skin is warm 

 and moist. The respiratory movements are less frequent, expiration 

 is sometimes sighing, there is often more or less oppression, and a 

 dry, painful, deep cough. The pulse is rapid, full and strong. On 

 auscultating the lung the vesicular murmur is found to be diminished 

 in the lower portion of one or other lobe, sometimes of both. Per- 

 cussion reveals lessened resonance. These symptoms become gradually 

 more marked, and in twenty-four to forty-eight hours others appear. 

 A reddish or rusty-coloured discharge runs from the nostrils, the colour 

 being due to blood elements contained in the pulmonary exudate. 

 Drying around the nostrils it forms a friable crust, resembling saffron, 

 sulphur, or iron rust in colour. As a general rule this discharge 

 remains somewhat abundant for several days. Sometimes a sanguino- 

 lent discharge is seen from the outset. 



