Abstract
Diseases of the spectacle in snakes are common and include pseudobuphthalmos and subspectacular infections, due to bacterial, fungal or protozoal organisms or trauma.1 However, subspectacular nematode infections are very rare. Only one report exists of subspectacular nematodiasis caused by Rhabdias martinoi in wild grass snakes (Natrix natrix) from Russia.2 Subspectacular nematodiasis was diagnosed in captive-bred juvenile ball pythons (Python regius) from two unrelated facilities in Wisconsin and Virginia within a six-month period. The snakes presented with similar lesions, including swelling of facial, periocular and oral tissues. Bilaterally the subspectacular spaces were distended and filled with an opaque fluid, which contained adult nematodes and eggs. Euthanasia was performed and histopathology showed nematodes throughout the periocular tissue, subspectacular space and subcutaneous tissue of the head. The nematodes from both facilities were confirmed to be morphologically identical and most closely resembled Rhabdias species. PCR sequencing and morphological characterization indicate this is likely a previously undescribed rhabdiasid nematode. The Rhabdiasidae are obligate zooparasitic nematodes with heterogonic life-cycles. The mulch substrate was suspected to be the most likely source of infection in the Wisconsin cases, since the snakes were hatched and kept in isolation by a breeder and full necropsies of feeder rodents and fecal exams of other adult snakes were negative for nematodes. This is the first report of subspectacular nematodiasis in captive snakes, caused by a novel Rhabdias species.
Literature Cited
1. Hausmann JC, Hollingsworth SR, Hawkins MG, Kass PH, Maggs DJ. Distribution and outcome of ocular lesions in snakes examined at a veterinary teaching hospital: 67 cases (1985–2010). J Am Vet Med Assoc. 2013;243:252–260.
2. Kurochkin YV, Guscov EP. A new nematode species from the eye of Natrix natrix. In: Helminths of Man, Animals and Plants and their Control: Papers on Helminthology Presented to Academician K. I. Skryabin on his 85th Birthday. Moscow, Izdatelstvo Akad, Nauk, SSSR. 1963:183–185.