ANNUAL REPORT, 1943-44 69 



Coccidiosis (135), infectious bronchitis (73), tumors (67), puliorum disease 

 (43), and so-called unknown disease (41) were the disease disburbances encoun- 

 tered most frequently. The tumors were classified on the basis of gross exam- 

 ination as follows: 44 lyniphoc>toma, 6 leukemia, 3 each of carcinoma and mye- 

 locytoma, 2 each of embryonal nephroma, hematoma, and unidentified; and 1 

 each of hepatoma, hemangioma, melanoma, myxoma, and thymoma. Avian 

 tuberculosis was identified once and fowl typhoid twice. Fowl cholera was 

 identified on 16 additional premises, bringing the total number of premises known 

 to be infected during the past 10 years to 71. Fowl cholera was found in ducks 

 and turkeys as well as chickens. A serious outbreak of avian tuberculosis was 

 identified in pheasants on one farm. Subsequent investigation by representa- 

 tives of the Bureau of Animal Industry, United States Department of Agricul- 

 ture, revealed that over 90 percent of the old birds and about 6 percent of the 

 young birds were infected. 



A disease disturbance caused by coal tar, creosote, and anthracene oil was 

 recognized in chicks. Chicks brooded from the time they are a day old in quarters 

 recently treated with one of these products, may manifest trouble at about three 

 weeks of age. The disturbance is similar to that observed in chicks fed rations 

 containing excessive salt. Affected chicks may show retarded growth, ragged 

 feathering, somnolence, difficult breathing, coughing, and moist tracheal rattling. 

 Postmortem examination may reveal extensive edema of the subcutaneous tissues 

 and the lungs, and an increase in fluid in the pericardial and body cavities. 

 Cardiac enlargement, splenic atrophy, and sometimes pneumonia are observed. 

 The kidneys and liver may vary in size but are usually swollen. 



The 332 turkeys were received in 63 consignments. The diseases encountered 

 most frequently were coccidiosis and enterohepatitis. Paratyphoid infection 

 was encountered less frequently than formerly; whereas the number of cases of 

 puliorum disease was the same as for the previous year. Disturbance due to a 

 lack of vitamin A was recognized in birds of nearly marketable age. Two cases 

 of fowl cholera were noted. Sinusitis, which had not come to our attention 

 earlier, was identified in three cases. A serious outbreak of disease in one flock 

 was identified as hexamitiasis. 



3. Flock Mortality Studies. In a continuation of the work on the flock main- 

 tained at the College for genetic studies, 317 morbid and dead birds have been 

 examined from the group hatched in the spring of 1942. There were 169 females 

 and 148 males. The number of males examined was much higher than for any 

 previous year, partly, no doubt, because of a greater eft'ort to get all specimens to 

 the laboratory. 



The female population was sacrificed in January 1944 because of an acute out- 

 break of puliorum disease. This made onlj' a minor difi^erence in the records 

 because only a small percentage of the population remained at the time of the 

 outbreak, since the birds had completed their first laying year and had been 

 disposed of in accordance with the usual practice. The origin of the puliorum 

 infection was not established. The major portion of the infection was in a house 

 containing birds, all of which were over 18 months of age. Repeated retesting 

 of the remainder of the flock has failed to reveal additional infected birds. 



Cannibalism was the primary cause of death of 54 females. Losses from canni- 

 balism were particularly severe from March to August or during the period when 

 the birds were over one year of age. Reproductive disorders (30), tumors and 

 leukemia (26), fowl paralysis (14), and kidney disorders (11) were other important 

 disease conditions noted. The incidence of fowl paralysis, which follows an 

 erratic pattern in the flock, was less than one-third of that in the population of 



