Identifying Infectious Agents in Snakes (Boidae and Pythonidae) with and Without Respiratory Disease

Abstract

Mycoplasmas are known respiratory pathogens in tortoises, but few studies exist in snakes. To better understand the correlation with clinical signs and co-infections, samples from mycoplasma-positive snakes with and without clinical respiratory disease were analyzed. Oral swabs from 15 snakes (pythons n = 12, boas n = 3) were examined using polymerase chain reaction (PCR) and third-generation sequencing (TGS). Additionally, mycoplasma isolation assays were performed. Pathogens detected by PCR included Mycoplasmas (15/15, 100%), serpentoviruses (9/15, 60%), and Chlamydia sp. (2/15, 13%); those detected by TGS included Mycoplasmas (14/15, 93%), serpentoviruses (10/15, 67%), Chlamydia sp. (1/15, 7%), and 15 different bacterial species. Sequencing of the mycoplasma PCR products revealed a close genetic relationship to Mycoplasmopsis agassizii. TGS identified genetically distinct mycoplasmas and three different serpentoviruses. While mycoplasmas could not be successfully propagated, Brucella intermedia comb. nov. was identified in eight cultures. Respiratory disease in snakes is often multifactorial, involving various pathogens and environmental influences. This study demonstrates that comprehensive diagnostics are essential for understanding disease processes in snakes and improving the detection of diverse pathogens. Further research is needed to improve laboratory diagnostics for infectious diseases in reptiles and to better understand the roles of various pathogens in respiratory diseases in snakes.

Keywords: boa; mycoplasma; python; reptile; respiratory disease; serpentovirus; snake.

Figure 1

Clinical signs observed in individual snakes at the time of sample collection. (a) Ball python (Python regius) exhibiting mucous discharge, hyperemia of the mucous membranes, and mouth wheezing. (b) Ball python (Python regius) presenting with mucous discharge and a cream-colored coating on the oral mucosa. (c) Dumeril’s boa (Acrantophis dumerili) with mucous discharge and hyperemic mucous membranes.

Figure 2

Example of mycoplasma-like colonies observed under a stereomicroscope (×120) after 12 days of incubation at 37 ± 2 °C and 5% CO₂ on Friis agar medium of broth cultures having shown a color change. Culture from a sample taken from a ball python (Python regius; K9601).