68 POUIvTEY DISEASES AND THEIR TREATMENT. 



usually accompanied by diarrhea and thick mucus. In case it 

 is known that cholera is in the neighborhood, it is well for a 

 poultryman to examine, from day to day, the character of the 

 droppings on the dropping board." 



"The course of the disease may be rapid or slow in its prog- 

 ress through the flock. It may take all within a few days, or 

 the fowls may drop off by twos and threes through a period of 

 several weeks. After the first symptoms appear the develop- 

 ment in individual cases is usually rapid. Forty cases investi- 

 gated by Salmon averaged 3 days, but many birds die within 

 a few hours after the diarrhea sets in. The time required to 

 develop the disease after exposure or inoculation is given by 

 Salmon as 4 to 20 days." (Robinson). 



Examination of the dead birds shows inflammation of the 

 digestive organs, kidneys and mesenteries in nearly all cases. 

 According to Ward (Calif. Expt. Stat. Bui. 156) "punctiform 

 hemorrhages are found upon the heart with almost absolute 

 uniformity. The liver is very frequently marked with punc- 

 tiform whitish areas." Sections show that the areas of necrotic 

 tissue are present throughout the liver tissue. The blood ves- 

 sels of the liver are congested. According to Ward the next 

 most striking lesions are found in the reddened and bleeding 

 mucosa of the first and second folds of the small intestine (next 

 to the gizzard). These reddened areas can even be seen from 

 the outside of the intestine. The intestinal contents are of 

 either a cream colored pasty mass or may be brownish or even 

 green in color. "Lesions are very rarely observed in other 

 portions of the intestine. The ureters are noticeable in prac- 

 tically all cases by reason of the yellow-colored urates that 

 they contain. The nasal cavity, pharynx and oral cavity fre- 

 quently contain a viscous mucous fluid, probably regurgitated 

 from the crop." 



Etiology. Fowl cholera is caused by a bacterium known as 

 Bacterium bipolaris septicus. It is closely related to the bacil- 

 lus of rabbit septicaemia and the bacillus of swine plague. 

 "Under the microscope the bacterium presents either a circular 

 or oval outline. It is about i 50-thousandth of an inch broad 

 and 2 or 3 times as long. It grows best at from 85° to 105° F. 

 It has no power of movement, does not form spores, and is eas- 

 ily destroyed by drying, by the ordinary disinfectants and by a 

 temperature of 132° F. for 15 minutes." (Salmon). 



