6 



lowed this method, and consequently this department has been unable to draw 

 conclusions from work imder way by this plan. 



DISCUSSION OF THE PROBLEM PRESENTED BY THE BACILLARY WHITE 

 DIARRHOEA CONDITIONS IN MASSACHUSETTS 



The problem in disease control, as presented by the bacillary white diarrhoea 

 conditions in Massachusetts, is one in the study of an epizootic, which corresponds 

 with an epidemic among human beings. The real aim is to prevent the spread 

 of disease, and any successful procedure must be based on education, stimulation 

 of interest, and supervision. 



The education of poultrjinen on the matter of bacillary white diarrhoea has 

 been comparatively easy. Massachusetts poultrymen have learned that by intelli- 

 gent use of the laboratory they are able to establish new methods in poultry 

 sanitation, and in the conduct of their various poidtry activities. An increasing 

 number of poultrymen apply each year for the service and show a desire to co- 

 operate. Improvements in preventing bacillary white diarrhoea have resulted, and 

 many poultrjTnen are working as effective agents for such prevention in their 

 respective communities. As this type of organization is perfected, greater interest 

 will be stimulated, and all divisions of preventive medicine as applied to bacillary 

 white diarrhoea control will advance. 



With education and stimulation of interest, the third essential in plans of opera- 

 tion is direction and supervision in the details of control procedures. During 

 this testing season considerable advance has been made to these ends. Poultry- 

 men have not been antagonistic to direction, but on the contrary have been eager 

 to see the operation of both field and laboratory studies. Their opinions upon 

 matters of poultry husbandry have been valuable, and have helped the depart- 

 ment to fit scientific control methods to actiaal practice. This desire to be directed 

 is essential to the smooth operation of any plan requiring supervision of persons 

 at decentralized positions throughout the State. The poultrymen have learned that 

 the laboratory data are of little value unless the plans and directions suggested 

 in the reports are followed. 



The statistical data included in this bulletin are of importance in showing just 

 how far the disease control project on bacillary white diarrhoea is successful. 

 They show the increase in numbers of livable chicks hatched from eggs laid by 

 bacillary white diarrhoea-free hens. They also demonstrate the widespread oc- 

 currence of the disease, and furnish many facts which may contribute to our 

 knowledge of causes and prevention, as well as showing how poultrymen are 

 sharing in the control problem, 



LIVABIUTY OF CHICKS AND HATCHABILITY OF EGGS FROM BACILLARY 

 WHITE DIARRHOEA-FREE FLOCKS 



As a result of the correlation of laboratory and field studies, 38 poultry plants, 

 representing 11,082 breeding birds, have been found to be free from bacillary 

 white diarrhoea. During the last testing season, after a flock was reported as 

 having no reactors, this department sought to find where eggs had been sold for 

 hatching and where day-old chicks had been sold, in order to show the value of 

 the test as a means of establishing disease-free flocks from which clean stock 

 might be obtained. This year the same schedule has been followed. The cus- 

 tomers have been consulted without collusion with the owners, and therefore the 

 data obtained are as reliable as it is possible to procure. 



The livability of chicks at nearly all plants which buy from bacillary white 

 diarrhoea-free flocks has been excellent. The hatchability of the eggs has been 

 normal. If bacillary white diarrhoea is present in the breeding birds, the hatch- 

 ability of the eggs is seriously influenced. On the other hand, if bacillary white 

 diarrhoea is not present, it is no assurance that the hatch will be above normal. 

 Low hatchability in eggs is not altogether a disease problem. However, when 

 chicks are once procured, free from Salmonella pulhra infection, the chance of 

 their maturing is enhanced tremendously. White diarrhoea control has advanced 

 today in Massachusetts to a point where the original source of infection is being 

 eliminated, and chicks hatched have a fair. show to live. 



The following table shows the comparison of hatching qualities of eggs and 

 livability of chicks obtained as above indicated. 



