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STUDIES ON THE TRANSMISSION AND PREVENTION 

 OF CESTODE INFECTION IN CHICKENS 



John E. Gutberlet, Carroll College, Waukesha, Wis. 



Introduction. The problem of tapeworm infection in chickens 

 has received but little attention in the United States. ' In fact it 

 was entirely untouched until a few years ago when the subject was 

 opened by Stiles (1896) and work was begun by Eansom (1900, 

 1902, 1904, 1909) on poultry and other birds. At the present time 

 less than a dozen references constitutes the entire American lit- 

 erature on the subject. Five species of cestodes are known to in- 

 fest chickens in various parts of the United States. 



No work has been done on the life history of the forms 

 existing in this country. However, studies have been carried 

 on extensively with poultry cestodes in various other parts of the 

 world, though as yet very little has been finally determined. In 

 only one species of chicken eestode has the life cycle been demon- 

 strated experimentally. That is Davainea proglottina (Davaine) 

 for which Grassi and Rovelli (1889 : 372 ; 1892 : 30, 85) have shown 

 that the intermediate host is a slug (Limax cinereus). This species 

 of eestode has not as yet been reported in this country. 



Chickens are supposed to become infested with another species 

 through eating snails, a third through eating flies, and a fourth 

 through eating earthworms. Plana (1881-1882) found in a snail 

 (Helix) two cysticereoids which agree closely with the head of 

 Davainea tetragona (Molin). No experiments were performed to 

 demonstrate that the cysticercoid was the larval stage of that 

 species and the only evidence of their connection is the similarity 

 in form. Grassi and Rovelli (1892: 33, 87) found in flies cysticer- 

 eoids which closely resembled Choanotaenia mfundibuliformis and 

 base their conclusion of identity on the structural similarity. 



Grassi and Rovelli (1889 : 372 ; 1892 : 29) found in earthworms 

 (Allolhophora foetida) cysticereoids which they associated with the 

 scolex of Dicranotaenia sphenoides, a chicken eestode not reported 

 in this country. Here again the only evidence for regarding it to 

 be the larval stage of this species is a general structural likeness. 

 In no one of these three forms was the life cycle demonstrated ex- 

 perimentally. Such comparisons are not proof that the cysticer- 

 eoids are intermediate stages of definite species, but only give a 

 clue as to the probable life cycle. 



