244 MISCELLANEOUS INFECTIONS 



disease is an exceedingly chronic one, often extending over a 

 period of several months but usually terminating in death. 

 In the cases reported, the fowls were well kept and given an 

 abundance of nourishing food. There seems to be an inability 

 on the part of the affected animal to assimilate nourishment. 



§ 176. Morbid anatomy. The most conspicuous lesion 

 is extreme emaciation. According to Dawson the mucosa of 

 the duodenum contains areas in which the walls are deeply 

 reddened and in which the contents are of a mucoid substance. 

 The writer made a number of post-mortems in pigeons suffer- 

 ing from this disease without finding any gross tissue changes. 



The disease needs further investigation, but the fact that 

 an organism has been found in the duodenum in large numbers, 

 where it multiplies and apparently produces by-products that 

 are absorbed and which interfere with the normal metabolism 

 of the body, is of sufficient interest to call attention to the pre- 

 liminary findings herein mentioned. It is not unlikely that if 

 the present hypothesis concerning the nature of this disease is 

 verified, a numberof disorders now attributed to general causes 

 may be traced to some form of intestinal infection, 



REFERENCES 



I. Dawson. Asthenia (going light) in fowls. Annual Report 

 of the Bureau of Animal Industry, U. S. Department of Agriculture, 

 1898, p. 329. 



MISCELLANEOUS INFECTIONS 



§ 177. Diphtheria in calves and swine. Diphtheria 

 of calves is an infectious disease of young calves characterized 

 by the formation of a diphtheritic membrane (necrosis) on a 

 greater or less portion of the mucous membrane of the mouth 

 and throat. It often leads to septicemia and death. It is 

 caused by the Bacterium of necrosis, described by Bang. 



The affection is quite common in Europe but it does not 

 seem to be as well known in this country. 



