CONTROL OF BACILLARY WHITE DIARRHOEA 

 1926-1927 



By Henry Van Roekel 



During tlie testing season ending Marcii 1, 1927, tiie Massaciuisetts Agricul- 

 tural Experiment Station, tlirougii its Department of Veterinary Science and 

 Animal Patliology, was able for tiie first time to test nearly all flocks before 

 the breeding season. This was made possible by an increase in funds and in 

 personnel, and by the fine cooperation of poultrymen m returning promptly 

 the application cards submitted. The Massachusetts Association of Certified 

 Poultry Breeders has done, in addition, very good work in helping to control 

 and eradicate the disease. As a result, during the present season, more dis- 

 ease-free breeding flocks were available for the benefit of those purchasing 

 hatching eggs and day-old chicks than has heretofore been the case. 



Nature of the Infection 



Bacillary wiiite diarrhoea is an infectious disease which is very common 

 among poultry in this country. The disease is caused by a micro-organism 

 known as Salmonella puUoro. In the infected adult hen it may localize in the 

 ovary and be transmitted tiirougii the egg yolk to the chick. The disease does 

 its greatest damage among young chicks. Infected chicks which survive the 

 disease may in turn become carriers, tiie organism localizing in some part of 

 the body with an atRnity for the ovaries. Carriers of the organism may be de- 

 tected l)y the macroscopic agglutination test of the blood. All birds reacting 

 to the test should be culled out of the flock and disposed of immediately. 

 The premises should be thoroughly cleaned and disinfected after the reactors 

 have been removed. 



Service Rendered Under the Poultry Disease Elimination Law 

 for the Season Ending July 31, 1927 



During the 1926-1927 testing season, 127,327 birds were tested by the macro- 

 scopic ajiglutination test for bacillary white diarrhoea. Tables I and II 

 show the progress that has Ijeen made in eliminating tiie disease in this State. 



This season 249 flocks were tested as compared with 2U1 last year. Of this 

 number 105 flocks were tested for the first time as compared with 98 tested 

 for the first time last year. This shows that a large numl)er of new flocks 

 have been tested during the last two years. The number of birds representing 

 the 105 new flocks, however, is much less in proportion than the number rep- 

 resenting the previously tested flocks, as the table below shows. The flocks 

 tested for the first time show a smaller percentage of infection. Some of these 

 flocks represent poultrymen who have just started in the business and have 

 obtained stock from clean flocks. The higher percentage of infection in the 

 previously tested flocks can be accounted for by the fact that some flocks are 

 not tested consecutively each year, thus giving the infection an opportunity 

 to increase. The majority of the new flocks are very small in size, which may 

 influence the percentage of infection. Table III shows this year's findings in 

 flocks that were tested for the first time and in those that had been tested 

 previously. 



