434 Avian Dipbtliei'ia and Chicken Pox. 



later pale and cold to the touch. 1 he discharge emanating from 

 the mouth and nasal orifices soils the breast and emits an 

 unpleasant odor. The animals emaciate considerably, until they 

 finally die from exhaustion due to the associated diarrhea. 



Those cases in which the disease affects both the skin and 

 mucous membranes of the head, although not necessarily at 

 the same time, may be designated as mixed form. In the 

 majority of cases the skin of the head is first affected, and the 

 inflammatory process usually spreads from the corners of the 

 mouth, later, to the oral mucosa and from here to the neighbor- 

 ing cavities ; the reverse order is much less commonly observed. 

 No matter in what direction the process progresses the two 

 forms coalesce in such a variety of clinical pictures that in 

 the lethal cases one usually finds the signs of pox and of diph- 

 theria simultaneously, although developed to different degrees. 

 However, cases in which the mucous membranes alone are 

 aifected are not rare. 



The acute form of the disease as it has been almost ex- 

 clusively observed in southern countries (Algeria, Cuba), 

 begins with marked symptoms of a general infection (marked 

 lassitude, loss of appetite, difficulty of breathing, etc.), followed 

 on the second or third day by small yellowish-broAvn pseudo- 

 membranes on the inflamed oral mucosa, which in a very short 

 period of time develop to extensive deposits. Although the 

 process mostly affects the nasal cavities and conjunctivae, 

 deglutition and respiration are markedly impaired, and in- 

 testinal inflammation occurs causing rapid exhaustion, and 

 ending fatally within a few days. 



Course and prognosis. Cases in wdiich the disease is con- 

 fined to the skin run a favora])le course in the majority of 

 instances. The skin disease ceases to progress after a certain 

 time when the nodules have become dry and have been shed, 

 and spontaneous cure follows after 3 to 5 weeks. In this manner 

 even large nodes may fall off spontaneously; in other cases 

 there occur fresh nodules on other parts of the body, and in 

 these instances the disease runs over several months. 



Less favorable is the course of the diphtheritic disease of 

 the mucous membranes. In a goodly number of cases spon- 

 taneous arrest and cure follows in these instances, but as the 

 process is easily carried to the larynx and bronchi and often 

 involves the intestinal mucosa the mortality is much higher 

 on account of exhaustion or dyspnea. The disease usually 

 lasts 2 to 3 weeks, sometimes 1 to 2 months, and with transitory 

 improvement the time may be even more prolonged. Accord- 

 ing to Friedberger the moi'tality is 50-70%, and is much higher 

 in young birds, especially in those of highly bred varieties. 



