1Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN, USA; 2Department of Herpetology, Knoxville Zoological Gardens, Knoxville, TN, USA; 3Department of Comparative Medicine, College of Veterinary Medicine, University of Tennessee, Knoxville, TN, USA
Abstract
A long-term study of osteomyelitis in a colony of ridge-nose rattlesnakes (Crotalus willardi) found a single Salmonella arizonae serotype (56:z4,z23) cultured from affected bone in all but one animal.3 The latter animal had Providencia rettgeri cultured from all tissues examined. In contrast, this serotype was only grown once from the bowel (50 cloacal cultures and 3 intestinal cultures). All other Salmonella isolates belonged to subspecies diarizonae (14 serotypes) or enterica (two serotypes).
With serotype 56:z4,z23 being isolated so commonly from bone and not from the gastrointestinal tract, it seems likely that the organism is spread by a means other than the fecal–oral route. This idea is supported by the colony’s husbandry, which generally keeps snakes isolated, except during the breeding season. Bacterial cultures of reproductive tracts at necropsy (n=8) and non-fertilized yolk masses (n=2), yielded nine serotype 56:z4,z23 isolations, in either pure culture or in mixed cultures. The testis of one snake grew Salmonella diarizonae 48:i-z, but this organism was also isolated from the intestine of that snake. Similarly, five of six blood cultures grew Salmonella arizonae 56:z4,z23. Due to limited reproduction and the dispersal of the majority of progeny from this colony, determining if offspring developed osteomyelitis cannot be made. Transmission of Salmonella spp. in utero has been documented in chickens, snakes, and turtles.1,2,4 Our preliminary data suggests the organism responsible for the bony lesions is transmitted to offspring from the mother in utero.
Literature Cited
1. Chiodini, R.J. 1982. Transovarian passage, visceral distribution, and pathogenicity of Salmonella in snakes. Infect. Immun. 36:710–713.
2. Kaufman, A.F. and Z.L. White. 1966. An epidemiologic study of salmonellosis in turtles. Am. J. Epidemiol. 84:364–370.
3. Ramsay, E.C., G.B. Daniel, B.W. Tryon, J.I. Merryman, P.J. Morris, and D.A. Bemis. 2002. Osteomyelitis associated with Salmonella enterica ss arizonae in a colony of ridgenose rattlesnakes (Crotalus willardi). J. Zoo. Wildl. Med. 33:301–310.
4. Shivaprasad, H.L. 2003. Pullorum disease. In: Saif, Y.M. (ed.). 2003. Diseases of Poultry. 11th ed. Iowa St. University Press, Ames, Iowa. Pp. 568–582.