DISEASES OF THE RESPIRATORY PASSAGES 183 



fowls, during- damp, cold weather and more often in the fall 

 or spring. It may attack old hens. Here it is of economic 

 importance l)ecause of the loss in the egg yield. Many young 

 birds succuml) to its ravages. The mucous secretions of the 

 head contain the virus. A bacillus resem])ling in some re- 

 spects the diphtheria bacillus has been found accompanying 

 the disease which Colin and others have termed the bacillus 

 of fowl diphtheria. 



Symptoms. — The contagium is spread by the nasal dis- 

 charges becoming disseminated. The entire ilock in the course 

 of two to six weeks may become affected. The sick bird 

 stays apart from the balance of the flock and sits around with 

 I'uffled feathers and droopy wings. There is a partial loss 

 of appetite, tears may be seen to accumulate in the con- 

 junctiva. The outer nasal passage becomes closed and breath- 

 ing is accomplished with difficulty and by way of the mouth. 

 The bird sneezes and shakes its head. The eyes are kept 

 closed and the eyelids become adherent by a small amount 

 of secretions which dry on the outer edge of the lids. The 

 infra -orbital sinus may become filled and bulge out, much as 

 is often the case in roup. The mortality may run as high 

 as 95 per cent. The nasal secretions remain thin. It is dif- 

 ferentiated from roup by the fact that diphtheric membranes 

 never form in the mouth or eye and there are no sores on the 

 head in contagious nasal catarrh. 



Treatment. — The same treatment and other sanitary regu- 

 lations as in roup are indicated in this malady. 



CONJUNCTIVITIS 



Most inflammations of the respiratory passages extend to 

 and involve the eye structures also. These affections of the 

 eye have been described under catarrh, roup, etc. 



There are many causes of inflammation of the mucous 

 membrane of the eye aside from the specific germs heretofore 

 mentioned. A chick was brought to our laboratory with one 

 eye swollen. Upon examination, there was found a piece of 

 straw about one-fourth of an inch in length lodged in the 

 conjunctival sac. Upon removal of this piece of straw, and 

 the application of a one-per-cent solution of zinc sulphate, 

 the inflammation subsided in the course of a day or two. 



The number and variety of foreign bodies that may gain 

 access to the eye structures and set up inflammation are 

 num])erless. In most cases their careful removal and ^vash- 

 ing the eye with a saturated solution of boracic acid or a so- 

 lution of zinc sulphate and water, 1 to 100, constitute all 

 the treatment that is required. 



