70 MASS. EXPERIMENT STATION BULLETIN 417 



the previous year. The tumorous conditions were identified on the basis of gross 

 examination as leiomyoma (9), lymphocytoma (8), m)'eloc>toma (2), and miscel- 

 laneous (7). 



4. Salmonella Types Isolated. Fifteen strains of paratyphoid organisms were 

 recovered from consignments received from 11 poultry flocks and one herd each 

 of swine and foxes. Eight S. typhi-mtirium strains were isolated from three chick- 

 ens (including one mature bird), one fox, one turkey poult, and three adult pi- 



"geons. 5. tennessee, S. anatiim, S. worthington, and 5. bredeney were isolated in 

 one instance for each, the first two from poults and the last two from chicks. 

 S. hareilly was recovered from specimens from the same premises on two differ- 

 ent dates, one from a poult and the other from a chick. One of the 5. typhi- 

 murium strains was isolated from a poult from these premises also. 5. cholera- 

 suis var. Kunzendorf was recovered from a swine herd. 



We are greatly indebted to Dr. Philip Edwards, Department of Animal Path- 

 ology, University of Kentucky, Lexington, Kentucky, who identified these strains 

 as to type. 



5. Fowl Cholera in Ducks. During the past year, a severe epornitic of fowl 

 cholera occurred on a large duck farm in Massachusetts. No definite information 

 could be obtained as to the origin of the outbreak, but during May 1943, the 

 infection caused a sudden and heavy mortality in the flock especially among 

 the ducklings. In some instances evidence of infection could be observed in 

 ducks four to six weeks of age, but in many ciises the heavy losses did not occur 

 until the ducklings were eight to ten weeks of age. Losses varied among different 

 hatches. The characteristic symptoms and lesions described for duck cholera 

 were observed. 



A special request was made to the laboratory for assistance in controlling this 

 disease. Since autogenous bacterin has been recommended for the control of 

 duck cholera, this laboratory agreed to produce and supply sufificient bacterin to 

 inoculate the young ducklings that the owner planned to raise for the balance 

 of the season. A total of approximately 25,500 ducklings hatched from June 

 25th to September 18th was inoculated. A total of 88,200 cc. of bacterin was 

 supplied. Some lots of ducks received as many as four inoculations (2 cc. each) 

 at approximately two- week intervals. No uninoculated controls were maintained. 

 The mortality rate ranged from 3.3 to 79 percent for the difTerent lots. As the 

 season progressed the mortality rate declined, but with some fluctuation. 



The owner was inclined to believe that the use of bacterin caused a reduction 

 in losses. However, a critical analysis of the data did not justify such a conclusion. 

 It was evident that in some lots the use of the bacterin failed to control losses, 

 even though the first inoculation was made prior to signs of the infection. 



Sulfathiazole was also tested as to its efTectiveness in controlling active out- 

 breaks of duck cholera. The limited data obtained suggested that this drug had 

 little if any influence on the mortality of the disease. However, further experi- 

 mentation is necessary to arrive at a definite conclusion. 



The purpose of resorting to biologic therapy and chemotherapy was to aid 

 the owner to finish his rearing season with as little loss as possible. The main 

 objective was the elimination of the infection from the premises through a com- 

 plete depopulation and sanitary program. At this writing, no evidence of cholera 

 has been observed in young stock reared this season. However, sufficient time 

 has not elapsed to permit a statement as to whether or not the infection has been 

 completely eliminated. 



