166 



Biological Therapy 



Roup and Pox in Chickens 



Under this classification is grouped a number of patho- 

 logical conditions referred to by various authorities as roup, 

 canker, avian diphtheria, chicken pox and ordinary colds. 

 Although there has been little unison among investigators 

 as to the relation which each of these bears to the others, 

 it is now quite generally agreed that the primary etiological 

 factor of all of these conditions is a filterable virus. This 

 virus is responsible for the condition known as contagious 

 epithelioma and commonly called chicken pox, which is 

 characterized by lesions of the skin; where as the other 

 class of conditions affecting the eyes, oral and nasal pass- 

 ages is due to bacteria which act in a secondary manner. 

 The confusion regarding these conditions is considerably 

 increased by an apparent geographical difference in the clin- 

 ical aspect of the disease. On the Pacific coast chicken pox 

 is a serious and primary condition and roup is secondary and 

 of less' importance. In other sections of the country pox is 

 not a particularly virulent disease and is more frequently 

 seen as a complication of roup. Irrespective of the accuracy 

 of these divergent opinions and aspects of the disease it is 

 quite generally agreed that losses from the filterable virus 

 are not particularly serious but that the more serious factor 

 and the cause for the high mortality associated with these 

 conditions is the group of bacteria which act as secondary 

 invaders and are responsible for the complications. Among 

 this group the most important are probably B. pseudodiph- 

 theria, B. pyocyaneus and streptococcus. 



SYMPTOMS OF ROUP. This disease may assume any 

 one of several forms as a result of which the symptoms show 

 some variation. In some cases the mortality may not exceed 

 ten per cent while in others it may reach ninety per cent. 

 The disease is most prevalent during the fall and winter 

 months. 



The first symptoms are usually apparent in the eyes, 

 when one or both display a watery discharge which rapidly 

 becomes thick and cheesy. The eyelids become adherent, 

 destroying the vision and allowing an accumulation to occur 

 in the conjunctival sac. The local infiammation and the 

 pressure caused by this accumulation eventually causes the 

 destruction of the eyes. A nasal discharge becomes appar- 

 ent. This is cheesy in character and because of its accumu- 

 lation and pressure on the palate causes a distention and 

 swelling on one or both sides of the head below the 



