April, 1935] Agricultural Research in N. H. 25 



The principal diseases of the adult group were : ruptured egg yolk 57% ; 

 coccidiosis 16% ; nephritis (inflammation of kidneys) 14% ; pneumonia 

 13% ; indigestion 10% ; tumors 6.7% ; and round worms 5.8%. 



The principal diseases of the chicks were : pneumonia 49% ; coccidiosis 

 12% ; pullorum disease 10.1% ; indigestion 8.7% ; and navel infection 7.6%. 



An inspection of all birds dying on ten poultry farms under the adult 

 mortality project represents about two thirds of the adult chicken autopsies 

 and one third of the chick autopsies of this report. (C. L. Martin and C. A. 

 Bofforff — MisceUancons Iiicoiiic. ) 



Adult Mortality 



Of the 1,042 adult birds examined, ruptured egg yolk condition was the 

 main ofifender with 43%, followed by pneumonia with 16.17%), nephritis 

 15.8%, indigestion 7.3%, and coccidiosis 7.2%. Of the 355 chicks examined 

 under this project pneumonia was first with 74.3%, followed by indigestion, 

 24.7%; navel infection 14.7%; and coccidiosis 6.7%. (C. L. Martin and 

 C. A. Bottorff—State Fund.) 



Ruptured Egg Yolk in Domestic Fowl 



There were about 30 birds with ruptured egg yolk condition studied this 

 year. Cultures were made from the heart, lungs, liver spleen, kidneys, ova, 

 yolk material and peritoneal fluid. Ten difl^erent species of bacteria were 

 isolated. 



Representative strains of these bacteria which showed possible signifi- 

 cance to ruptured egg yolk were injected into the peritoneal cavity of healthy 

 laying birds. Their physical condition did not change to any marked degree. 

 Tw^o did, however, stop laying. A second intraperitoneal inoculation was 

 made two weeks after the first and some of the birds became droopy, but 

 recovered in two days. Autopsies showed that none of the cultures injected 

 produced the ruptured egg yolk condition. Two of the species of organisms 

 did produce peritonitis. 



An attempt has also been made to determine if an active, living 

 causative agent is present in the ruptured egg yolk material taken from birds 

 which have died from this trouble. This material has been injected into the 

 peritoneal cavity of healthy laying birds. No evidences of infection was 

 noted. 



Losses from ruptured egg yolk have been greatly diminished by more 

 careful handling of the birds and by making perches and laying nests more 

 easily accessible. (C. L. Martin. C. A. Bottnrjf. and L. W. Slanets — Pnr- 

 riell Fund.) 



Control and Vaccination — Infectious Laryngotracheitis 



Infectious Laryngotracheitis epidemic started in New Hampshire in 

 March. 1934. By June it had spread to five farms in the State involving over 

 75,000 birds. As soon as the disease was discovered, the flocks were vacci- 

 nated with an autogenous vaccine prepared from the aflfected birds. The 

 mortality varied from 5% to 15% as compared to 50% in cases where no 

 vaccination was practiced. 



