ANNUAL REPORT, 1934 75 



progeny was classified at eight or nine weeks of age for early or late feathering. 

 Results to date indicate that autosomal genes are concerned in the rate of feath- 

 ering in Rhode Island Reds. 



Breeding for Low Mortality. (F. A. Hays.) An attempt is being made to 

 establish by selective breeding a line of birds with very low mortality rate in the 

 laying houses and a second line with very high mortality. In the spring of 1934 

 one male was selected from a family with low mortality and another male from 

 a family having extremely high mortality. These two males were each mated to 

 a pen of females, part of which were classed as low in mortality and part as high 

 in mortality on the same basis that was used in selecting the males. Resulting 

 progeny are now being carried through the year. 



Breeding for High and Low Resistance to Fowl Paralysis. (F. A. Hays, C. S. 

 Gibbs, W. C. Sanctuary and J. H. Vondell.) This is a cooperative project between 

 the Departments of Poultry Husbandry and Veterinary Science, and was under- 

 taken in the spring of 1933 to discover whether inheritance plays a part in resis- 

 tance to fowl paralysis. Selection of breeding stock was based either on the 

 incidence of paralysis in the family or on its incidence in the offspring. Three 

 lines were established using two males with high incidence and one with low 

 incidence. On the female side each line included both hens and pullets with high 

 or low incidence of paralysis. 



The first generation progeny hatched in 1933 was carried as a whole up to 

 December when part of the males were discarded and the females retained. All 

 sick or dead birds were carefully studied for pathological symptoms. The second 

 generation hatched in 1934 was sired by cockerels from the three lines mated in 

 part to the original females and in part to first generation females. Progeny are 

 being handled in the same way as the first generation. 



General results indicate the more frequent occurrence of paralysis from the 

 high incidence matings. 



DEPARTMENT OF VETERINARY SCIENCE 

 J. B. Lentz in Charge 



Poultry Disease Control Service. (H. Van Roekel, K. L. Bullis, D. M. Yegian, 

 O. S. Flint, and M. K. Clarke.) 



1. Pullorum Disease Eradication. During the past year the Massachusetts 

 poultrymen have shown an interest in pullorum disease testing and eradication 

 which is equal to that of the previous season. This fact is encouraging, since 

 economic conditions were markedly unfavorable to the poultry industry. 



During the past testing season 262 flocks were tested, representing 263,241 

 tested birds, 284,848 tests, 0.53 percent positive tests, 229 negative flocks, and 

 33 positive flocks. As the result of testing over a period of years, great progress 

 is revealed by the fact that the number of flocks which had been tested for three 

 or more consecutive years was equal to 178, representing approximately 86 

 percent of the tests, of which 0.34 percent were positive. Only 11 of the 178 

 flocks were classified as infected, which shows that, through annual testing sup- 

 plemented by effective preventive measures, flocks can be maintained free from 

 pullorum disease. The primary object is to maintain the flocks free of the disease 

 and to establish additional clean flocks through closely supervised testing and 

 supervised replacements from known free flocks. 



