ANNUAL REPORT, 1944-45 65 



Additional field observations have been made on a disease disturbance in 

 chicks caused by exposure to coal-tar creosote oil, which was reported last year. 

 It appears probable that strong coal-tar disinfectants, so-called gas house tar, 

 and kerosene improperly used may cause the same type of injury. 



The 451 turkeys were received in 84 consignments which represents the largest 

 number ever received at the laboratory in one year. Coccidiosis, enterohepatitis, 

 pullorum disease, and paratyphoid were the diseases encountered most frequently. 

 An examination of the records for the past ten years reveals that diseases which 

 were unidentified or were directed to the attention of the laboratory only in- 

 frequently at the beginning of the period are now of major importance to the 

 turkey industry. A list of such diseases includes coccidiosis, hexamitiasis, 

 infectious sinusitis, moniliasis, paratyphoid infection, pullorum disease, swine 

 erysipelas, trichomoniasis, ulcerative enteritis, and so-called unknown disease 

 (blue comb). 



Two cases each of fowl cholera and fowl typhoid were identified in turkeys 

 during the year. A considerable number of cases revealed heavy infestations in 

 the lower digestive tract with motile protozoa which were identified as tricho- 

 monads. The observations suggest that these protozoa are pathogenic for 

 turkeys and in a number of cases it has appeared that they were responsible for 

 diarrhea, retarded growth, and mortality in poults. The infections with tricho- 

 monads are sometimes combined with coccidiosis and hexamitiasis, but fre- 

 quently the trichomonads appear to be the principal cause of disease outbreaks. 

 Microorganisms apparently belonging to the aerobic actinomycetes group were 

 recovered from two outbreaks of respiratory disease in turkeys. 



3. Flock Mortality Studies. From the Experiment Station flock hatched in 

 the spring of 1943, 368 morbid and dead birds have been examined — 227 females 

 and 141 males. Cannibalism (56), reproductive disorders (50), tumors and leuk- 

 enia (46), fowl paralysis (21), and kidney disorders (17) were the conditions 

 most frequently encountered among the females. Cannibalism (81), bacterial 

 and mycotic diseases, principally staphylococcosis, (17), and kidney disorders 

 (12) accounted for 70 percent of the diagnoses among the males. The tumorous 

 conditions in the population were identified on the basis of gross examination as 

 17 lymphocytoma, 8 leiomyoma, 5 each carcinoma and embryonal nephroma, 

 4 each myelocytoma and unidentified, 3 hemangioma, 2 leukemia, and 1 each 

 cyst-adenoma and neurogenic sarcoma. The majority of cases identified tenta- 

 tively as fowl paralysis failed to show gross lesions. Diagnoses of cannibalism 

 and reproductive disorders among the females were most frequent during a 

 period of six months, which began about three months after production started. 



Erysipelothrix rhusiopathiae was identified in one seven-months-old male. 

 The liver and spleen were slightly swollen and the heart muscle showed pale 

 areas. 



4. Infectious Bronchitis During 1944, 232 flocks representing approximately 

 400,000 birds were enrolled in the infectious bronchitis control program. These 

 flocks were located in Bristol, Essex, Franklin, Hampden, Hampshire, Middlesex, 

 Norfolk, and Plymouth counties. The procedure of the program was much the 

 same as in 1943, except that the service was placed on a fee basis. 



The results on the whole were satisfactory although in a few instances respira- 

 tory symptoms developed following the recovery from the infectious bronchitis 

 inoculation. The cause of the disturbance was not definitely identified. It 

 appeared that in some of these cases the infection was either an atypical form of 

 infectious bronchitis or some other respiratory infection which has not been 

 identified up to the present. 



