NASAL GLEET. 371 



galloping, and may be copious or consist only of a few drops. If 

 it is not frothy, it may be concluded that it does not proceed from 

 the lungs. It may be caused by fulness of blood to the head, or 

 by a diseased or weak condition of the blood-yessels of the mucous 

 membrane of the air-passages of the head, as, for instance, in the 

 case of a nsevus (p. 162) of that surface. Horses appear to be 

 more liable to this accident when they are pulling hard, than when 

 they are allowed to go freely. The only treatment which I advise, 

 and have successfully employed in two or three cases, is the injec- 

 tion up the nostril, of water of a temperature of about 120° to 

 125° F. (p. 65). I can suggest no preventative. The advisability 

 of putting the animal on laxative food, and gradually bringing 

 him on to work again, is self-evident. 



Nasal Gleet {Ozana). 



DEFINITION. — A chronic and stinking discharge from the nose, 

 due to local causes. It is a symptom of disease. If we use the 

 term " ozsena " (from o^rj, a bad smell) as a synonym for nasal 

 gleet, we must regard a foul odour as a necessary condition of the 

 discharge. We cannot put under this heading any somewhat 

 similar discharge arising from a general disease, as, for instance, 

 glanders. 



In the discharge of ozsena, there has been found two kiiids of bacteria, 

 namely, the bacillus foitidus ozana, of Hajek, and the bacillus smaragditms 

 fcetidua of Beiman, ' both of whicih_ produce a very offensive smell. The 

 question whether or not these organisms cause the disease has not yet been 

 answered. 



ANATOMY. — ^Under ordinary conditions, a horse breathes through his 

 nostrils, which are separated from each other by a cartilaginous partition. 

 In order to give a large surface for the attachment of muscles without 

 greatly adding to the weight, some of the bones of the horse's face are 

 hollowed out, so as to form, on each side, five cavities (or sinuses) ; the 

 three principal, which are the only ones that need our attention here, 

 being : the frontal, the superior ma^ollary, and the inferior maxillary sinus. 

 The sinuses on one side are divided from those on the other side by a bony 

 partition which runs down the centre of the face from a little above the 

 level of the eyes, and which may be regarded as a continuation of the 

 partition between the two nostrils. There is a common passage by which 

 aU the sinuses open into the nose ; and there is a passage between the 

 frontal sinus and the superior maxillary sinus. Under ordinary circum- 

 stances, the inferior maxillary sinus does not communicate with any of the 

 other sinuses. The sinuses of the head are " blind " cavities, through 

 which, practically speaking, there is no passage of air. The volume of air, 

 however, appears to be changed by a slight alteration of tension during 

 breathing. 



The frontal sinus, on each side, lies underneath the bone of the forehead, 

 between the eye and the middle line of the face. It extends about three 

 inches above, and about the same distance below, a line joining the centres 

 of the two eyes and drawn across the forehead. 



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