ANNUAL REPORT, 1933 57 



Pullorum Disease Investigations. (H. \an Roekel, K. L. Bullis, O. S. Flint, 

 D. M. Yegian, and Miriam K. Clarke.) 



1. Cause of Doubtful Reactions. These reactions occur in many birds from 

 which S. pullorum cannot be isolated. Antigens were prepared from members 

 of the typhoid, paratyphoid, and dysentery groups of bacteria. Agglutination 

 tests were conducted with 1 1 species of these groups, employing 20 positive, 20 

 negative, and 39 doubtful pullorum sera. The positive and doubtful sera pro- 

 duced reactions in the majority of the antigens, while the negative sera reacted 

 mainly with the dysentery antigens. Agglutinin absorption tests in a few sera 

 also indicated that the dysentery group probably was not associated with the 

 doubtful pullorum reactions. Thirty-three negative and ten doubtful sera were 

 tested with 33 single strain antigens, representing 12 species of the three groups. 

 Results of these tests were similar to the previous tests. Twenty birds were 

 inoculated with 20 strains of 1 1 species, representing the three groups. Sara 

 from these birds were tested with the 33 single strain antigens. The tests indi- 

 cated that by employing ordinary laboratory cultures the agglutination relation- 

 ships of 5. pullorum, S. gallinarum, S. abortivo-equina, S. enteritidis, S. aertrycke, 

 and E. typhi were so close that the sera could not be differentiated by the agglu- 

 tination method alone. The 5. suipestifer, S. schotmulleri, and Al. fecalis sera 

 could be differentiated. The dysentery sera could be differentiated from all the 

 others, and within the group the Sonne and Flexner types reacted differently. 

 Considerable variation in agglutinability was noted within each species. 



2. Infectivity of Droppings. Tw'enty-five hens, negative to the tube agglutina- 

 tion test, were exposed to litter contaminated with fresh droppings from positive 

 hens. The exposure consisted of approximately one pint of fresh droppings si.x 

 days a week for 52 weeks. Up to the present time, two months after the litter 

 contaminations ceased, there have been no positive reactions. 



3. Viability of S. pullorum. The organism has been recovered from a dry 

 piece of cloth after a period of 503 days. Part of this was reported in a Master's 

 thesis by M. K. C. 



Laboratory Service— Pathology. (K. L. Bullis and D. M. Yegian.) Personal 

 calls at the laboratory were recorded 107 times. The number of cases handled 

 was 366 and the number of specimens 1,116. Distribution of the specimens 

 was as follows: — 1,041 chickens, 26 turkeys, 20 rabbits, 9 quail, 6 pheasants, 

 5 sheep, 2 grouse, 2 guinea pigs, and 1 each of the following: — canary, cow, dog, 

 hay, and prgeon. The diseases encountered most frequently were parasitism, 

 so-called "range paralysis," pullorum disease, and tumors. Disturbances of the 

 kidnej- and oviduct were found in a large number of specimens. Several cases 

 of entero-hepatitis in chickens were recorded. Diagnoses of diseases which are 

 believed to be rare in Massachusetts were: — fowl typhoid 4, fowl cholera 2, and 

 1 each of avian tuberculosis, intestinal capillaria, erythroleukosis, feather mites, 

 paratyphoid in turkeys, and gape worms in quail. A fatal case of corynebacterium 

 infection was diagnosed in a pullet. A search of the literature did not reveal a 

 description of this organism. 



Farm and Station Bang Disease. In assisting this project, the laboratory 

 tested 850 blood samples by the standard tube agglutination method. 



Infectious Laryngotracheitis Field Experiments. (C. S. Gibbs.) Approx- 

 imately 11,000 chickens were vaccinated against infectious laryngotracheitis 

 during the summer of 1933 under range conditions. An especially virulent strain 



