604 MICROBIOLOGY OF THE DISEASES OF MAN AND ANIMALS. 



and the excretions of animals dead of the disease should be collected 

 and burned. 



The stalls, stables, implements and anything that has been in contact 

 with the diseased animals should be disinfected by burning, boiling or 

 the use of some disinfectant like 5 per cent carbolic acid. 



BACILLARY WHITE DIARRHOEA OF YOUNG CHICKS.* 

 Bacterium pullorum. 



The epidemic type of diarrhoea which is characterized in part by a 

 whitish diarrhceal discharge, and which is now known as "bacillary 

 white diarrhoea," is caused by a bacterium which belongs to the colon- 

 typhoid group of bacteria. It has many points in common with the 

 typhoid bacillus. It may be cultivated easily on the ordinary laboratory 

 media, but its growth on slant or plate agar is delicate, and very much 

 like that of the Strept. pyogenes. This peculiar appearance on agar is 

 a great aid in the identification of the bacterium and hence in the 

 diagnosis of the disease. 



This organism, which has been named Bact. pullorum, is present in 

 the intestine, liver, lung, spleen, kidney, heart, and unabsorbed yolk of 

 chicks suffering with the disease in question. It is to be obtained most 

 easily from the liver and yolk, when the latter is present. 



Feeding experiments conducted on a large scale demonstrated that 

 the disease may be transmitted to young chicks under three days old 

 through infected food and drinking water. Furthermore, chicks may be 

 infected with Bact. pullorum before hatching. These two facts furnish 

 an easy explanation as to the rapid spread of the infection among chicks, 

 many of which were normal at the time of hatching. 



The mother hen is the source of infection in the egg. The examina- 

 tion of hens from which it was almost impossible to raise chicks, on 

 account of white diarrhoea, revealed the fact that the ovaries were infected 

 with Bact. pullorum. The diseased ova were very abnormal. They 

 were discolored, misshapen, and of all degrees of consistency. Eggs 

 from these hens have been found to contain the specific bacterium in 

 question in all stages of incubation. Later, a method was devised for 

 identifying the bacterium in fresh eggs which came from infected flocks. 

 Numerous eggs were tested and the organism was observed in many 



* Prepared by L. P. Rettger. 



