26 a EXPERIMENT STATION. [Jan. 



THE AGGLUTINATION TEST FOR THE ELIMINATION OF 

 WHITE DIARRHEA IN POULTRY. 



The work of Jones of Cornell, Rettger of Yale, and Dr. Gage 

 of this station — the latter fully reported in Bulletin 163 — 

 having shown that white diarrhea, which has been the occasion 

 of so much loss to poultry keepers because of the death of so 

 large a proportion of young chicks affected with the disease, is 

 in most cases due to the infection of the egg. from the ovary of 

 the hen producing it, and that the hens harboring the organism 

 can be almost certainly detected by a comparatively simple 

 blood test, it was decided to carry out this test on the flocks of 

 poultrymen applying for it in so far as the facilities and force 

 at our disposal made it possible on the basis of a payment to the 

 station at the rate of five cents for each fowl tested. This work 

 was begun in a small way in the winter of 1915. It became 

 possible in the late summer to undertake it upon a considerably 

 more extensive scale through an arrangement for the collection 

 of the samples of blood by Prof. A. G. Lunn, who is engaged in 

 poultry extension work. It was thought that Mr. Lunn would 

 be able to collect samples in as great number as could be 

 handled in our laboratories with the force available for the 

 work without serious interference with his extension duties. 

 This expectation was not fully realized. The number of blood 

 samples which he found it possible to take was not sufficiently 

 great nor forwarded with sufficient regularity to afford steady 

 employment for our laboratory forces. A good beginning, how- 

 ever, was made, and between September 11 (when the work 

 began) and the end of the year 2,728 birds were tested. So far 

 as follow-up work and the reports from individuals whose breed- 

 ing flocks have been tested indicate, the results of the work are 

 very satisfactory, as the losses of chicks hatched from eggs of 

 birds which passed the test have been far less than the losses 

 in chicks belonging to the same owners when eggs from un- 

 tested breeding flocks were hatched. 



