2 PROTOZOAN PARASITES. 



I. PROTOZOAN PARASITES. 



A. Diphtheritic Roup. 



Amongst the least understood parasitic diseases of 

 Poultry, Diphtheritic Roup stands paramount. That 

 it is due to certain minute and lowly animal forms 

 there is much evidence to show, but nevertheless we 

 know comparatively little regarding the Pathology 

 and Etiology of this often disastrous epidemic in the 

 Poultrv World. Like very many things that have 

 not been studied scientifically. Diphtheritic Roup has 

 been commingled with other complaints of a perfectly 

 different facies. Even ' science 3 is at variance upon 

 this subject, for the nature of this complaint is a 

 subject of very diverse opinions. It is possible, and 

 I feel sure this is the case, that there are three kinds 

 of affections grouped under the name Diphtheria. 

 Two of these are certainly due to minute Protozoan 

 parasites ; the third, which I have not so far been 

 able to observe, may be due, as stated, to some minute 

 microbe. Colin and Roux have demonstrated this 

 latter point, and they show that the microbe of 

 Chicken Diphtheria is not the same as produces the 

 similar named disease in man. 



Appearance and Symptoms of the Disease. 



The disease manifests itself as white and creamy 

 patches in the mouth, pharynx, and even in the 

 crop. The upper surfaces of the growths are slimy 



