UNIVERSITY OF CALIFORNIA PUBLICATIONS 



IN 



ZOOLOGY 



Vol. 1 1, No. 3, pp. 29-51 January 30, 1913 



A STUDY OF EPITHELIOMA CONTAGIOSUM 

 OP THE COMMON POWL* 



BY 



CLIFFORD D. SWEET 



CONTENTS 



PAGE 



Introduction 29 



Clinical Features 32 



Pathology 36 



Immunity 40 



Complement Fixation 43 



Conclusions 48 



Literature Cited 49 



INTRODUCTION 



Economic Importance. — Prom an economic standpoint epith- 

 elioma eontagiosum is a disea.se of considerable interest. In cer- 

 tain localities, notablj' in the Hawaian Islands, and South Africa, 

 it is one of the chief obstacles to the profitable raising of poultry. 

 It attacks young fowls, is very contagious and proves fatal in 

 a large percentage of the fowls attacked. In California it is 

 apparently less widespread and seemingly has not so great a mor- 

 tality percentage as in the above-mentioned countries. However, 

 even here, a clear understanding of the epidemiology of the dis- 

 ease, with the control such a knowledge would give of its incidence 

 and spread, would be of very considerable economic value. 



* Submitted to the Department of Zoology, in partial fulfillment of the 

 requirements for the degree of Master of Science, in the University of 

 California, April 22, 1912. 



