Paracolon type 10 from captive rattlesnakes.

During the spring of 1942 a paracolon type was isolated by the authors from a captive rattlesnake at the San Diego Zoo. This culture (Pc27) was studied by Edwards, Cherry, and Bruner (J. Infectious Diseases, 73, 229) and designated by them as "type 10." The antigenic formula is XVIII Z4 x2 X7. Since that time this type has been found to be the cause of considerable mortality in turkey poults in the same area (Hinshaw and McNeil: J. Bact., 51, 281). The present paper reports further isolations from the same cage (A-31) of rattlesnakes from which the original one was made. Acc. 144-1. This male rattler (Crotalus viridis-oreganus) died on June 1, 1942. The only symptom of previous illness was that it had disgorged the rat fed to it on February 1, 1942. However, at death it was fat and in a good state of preservation. On necropsy the organs did not show the usual enzymic decomposition noted in dead reptiles. This indicates that death was the result of an acute disease. The only lesions were numerous small, necrotic areas in the liver. From these lesions a type 10 paracolon (Pc27) was isolated in pure culture; other organs were not cultured. This snake had been in the cage since its capture in June, 1937, in Lower California. Acc. 2£6-2. On September 7, 1943, an emaciated sidewinder (Crotalus cerastes) of unknown history, was killed. With the exception of an enlarged gall bladder all organs appeared normal. From the liver of this snake a paracolon type was isolated which has the flagellar antigens of type 10, but a new somatic antigen. Acc. 2£5-3. On September 7, 1943, a type 10 paracolon was recovered from a fecal sample from this cage. Acc. 2£6-9. On September 28, 1943, a female prairie rattler (Crotalus viridis) died. It had been in this cage since June 6, 1943, and had not eaten since that time, although it undoubtedly drank water during those months. Type 10 was recovered from the kidney, lungs, and uterus. Acc. 235-17. On October 17, 1943, a young female rattlesnake (C. vtiidisoreganus) died. It had been in cage A-31 since June 23, 1943. The bile was thick and "tarry"; other organs appeared normal. Type 10 was isolated from the liver, ovary, lungs, heart blood, kidney, and intestine. Acc. 236-64. On January 19, 1944, a male sidewinder (Crotalus cerastes), of