E. histolytica: carnivores and rodents 



difference between the types found in man and monkey. 

 (Discussions of the amoebae of monkeys may be found 

 in the books of Dobell (1919a) and Wenyon (1926), 

 and in the recent papers by Brug (1923), Mello (1923), 

 Suldey (1924), Kessel (1924), Dobell (1926b) and 

 Dobell and Laidlaw (1926b). 



Carnivores. Spontaneous amoebic dysentery has also 

 been reported in cats and dogs, and kittens have proved 

 to be more easily infected with E. histolytica than any 

 other lower animal (see pp. loi, 105). Infections may be 

 brought about by feeding cysts to the experimental ani- 

 mal or injecting trophozoites per anum. When an infec- 

 tion is obtained in cats it is usually acute and recovery 

 is rare. Kruse and Pasquale (1894) claim to have in- 

 fected a cat with amoebae from a liver abscess. Liver 

 abscesses have been reported in both cats and dogs. 



Rodents. Rats and Mice. Recent experiments on the 

 infection of rats with E. histolytica have been carried 

 on by Brug (1919a), Kessel (1923), Wagener and 

 Thomson (1924) and Chiang (1925a, 1925b). Brug 

 found two wild rats in Java which were infected with 

 amoebae that apparently belonged to the species E. histo- 

 lytica, and reported the experimental infection of a speci- 

 men of Mus rattus with E. histolytica from man. Kessel 

 had no difficulty in infecting young rats and mice by feed- 

 ing them human feces containing cysts of E. histolytica 

 and of other human amoebae. Transfer of these human 

 amoebae from one rat to another was also successfully 

 accomplished. No morphological or racial differences 

 could be found between the amoebae before and after they 

 had been established in the rat hosts. The infections in 



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