480 THE BACTERIOPHAGE AND ITS BEHAVIOR 



the study with which we are concerned.* It is sufficient to know that 

 in France in the epizootic of 1919 the most frequent pathogenic agent 

 was of the B. gallinarum type (found in 57 of 73 examinations). Along 

 with B. gallinarum other forms have been found: B. pullorum A (once), 

 B. pullorum B (6 times), B. jeffersonii (4 times), and B. pfafl (4 times). 

 In a single focus, of which the centre was found in the village of Trainel 

 (Aube), a paratyphosis infection occurred due solely to B. pfaffi without 

 admixture with bacilli of the true typhosis type. 



The clinical picture hardly varies whatever may be the causative 

 bacillus. A typical observation follows. 



On the evening of May 24 the chicken appeared perfectly well. On 

 the morning of May 25 it remained apathetically on the ground of the 

 poultry-yard and took no measures for its defense. The next day, 

 toward noon, it appeared somnolent, the plumage rough, the eyes half- 

 closed, the crest slightly violet colored. It did not eat or drink, and 

 remained humped up "in a ball." The inspirations were deep, twenty- 

 five per minute. There was a greenish yellow diarrhea with portions 

 definitely yellow. The condition became worse in the afternoon. It 

 fell on its side at about 8 o'clock and died a few minutes later. The 

 necropsy showed the crest to be violet in color, with spots of the same 

 nature over the skin. The liver was voluminous, congested, and pre- 

 sented foci of degeneration. There was a pericarditis. 



By direct microscopic examination the blood at first appeared neg- 

 ative, but a very careful search revealed three bacilli in a whole smear. 

 The blood and tissues when cultured gave a pure growth of B. gal- 

 linarum, and this organism was also found, very abundantly, in the 

 intestinal contents. 



Sometimes death occurs more rapidly still, in certain cases in a strik- 

 ing manner. Epizootics of avian typhosis have a high mortality. In 

 1919 foci existed throughout the extent of France. In general, the 

 epizootic begins quickly; within the space of three or four weeks a half, 

 three-quarters, sometimes more, of the fowls on a farm succumb. Then 

 the disease assumes a sporadic character, only an occasional animal 

 dying during the course of a year. The disease may disappear for a 

 few months and then reappear. The annual mortality amounts to 

 forty to seventy per cent of the population of the infected poultry- 



* Readers who are interested in the subject will find much useful information 

 in the contribution of Ph. Hadley, The Colon-Typhoid Intermediates as Causa- 

 tive Agents of Diseases in Birds. Bulletin No. 174, Rhode Island Agric. Exper. 

 Sta., 1918. 



