224 JOHN E. GUTBERLET 



Symptoms and Effects of Tapeworm Infection. A great 

 deal has been written on the symptoms of this disease by various 

 authors, but in every case they were unable to reach any definite 

 conclusions on the subject. In my own study, which was exten- 

 sive, I reached the following definite conclusions: The symptoms, 

 while not really individual, vary to some extent with the different 

 birds, with the age of the birds, and with the degree of infection. 

 Some birds are affected by the disease much more than others and 

 show sj^mptoms and effects much more readily. Some birds that 

 show no symptoms and appear in good health are heavily infested 

 with the worms, while others showing severe effects and manifesting 

 all the symptoms are not nearly as heavily infested. The age of the 

 host is a factor of much importance for indicating the presence of 

 an infection with the species I studied. Young, growing birds are 

 affected much more than adults and show the symptoms more dis- 

 tinctly. Even a comparatively slight infection can be detected in 

 a young bird a few weeks of age, while a heavy infection is very 

 marked. Most adults manifest no external symptoms as far as 

 appearance is concerned unless they are heavily infested. The de- 

 gree of infection is another factor which is of importance in 

 making a diagnosis for cestodes. Birds that harbor only a few 

 worms show conditions which are quite different from those that 

 possess a large number. Therefore the symptoms are rather var- 

 iable. 



Stiles (1896: 13) mentions some general principles for diag- 

 nosis, and Zurn (1882: 17) gives more fully some of the symptoms 

 that may be taken as indications of the disease in the birds. 



In general, one may say that a light infection can hardly be 

 noticed and is apparently in no way harmful to the fowl. In 

 cases suffering from a moderate to a heavy infection the conditions 

 were found to be quite different. In the first place, birds that are 

 moderately infested are apparently always hungry, having in- 

 deed ravenous appetites and seeming never to be able to get enough 

 to eat. Secondly, they manifest a great desire for water, increas- 

 ing in cases where the infection is heavy. Moreover, infected birds 

 are greedy and it seems as if their hunger had caused them to lose 

 control of themselves whenever there is a chance to obtain any food. 

 Such birds are also restless, always moving about as if searching 

 for something. This in part probably accounts for the fact that 

 the fowls are poor in flesh and more or less in an emaciated con- 



