Cryptosporidium serpentis in snakes
By Eric Snook, DVM, PhD
An adult black tailed Cribo (Drymarchon melanurus), a snake native to Central and South America, was presented for necropsy at the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for chronic regurgitation. Upon necropsy examination, the stomach was markedly thickened with prominent rugal folds. The remainder of the visceral organs appeared within normal limits. Histologically, the gastric glands were markedly hyperplastic with moderate numbers of heterophils and a few mixed inflammatory cells. Adhered to the mucosal epithelium were numerous, 2-6 micron diameter, round, pale, amphophilic to basophilic protozoa with distinct 1-2 micron basophilic nuclei.
The organisms in the stomach are compatible with Cryptosporidium serpentis. Cryptosporidium is a highly infectious, single-celled protozoan that colonizes the gastrointestinal and respiratory surface epithelium of mammals, birds, reptiles, and fish. In snakes, Cryptosporidium reduces acid secretion of the acid-secreting granular cells with associated mucus metaplasia and hyperplasia of the mucus neck cells. This results in gastric mucosal hypertrophy (prominent thickened, rugal folds as noted in this particular snake). In snakes, the organisms are generally found in the stomach, which typically leads to regurgitation 1 to 3 days after eating. Because they are not assimilating food well, the snakes will often exhibit emaciation over time. There is no current effective treatment for this organism. Frequently affected snakes will die or be euthanized due to severe gastrointestinal signs.
For more information on the case, contact Dr. Eric Snook, veterinary pathologist at the College Station laboratory. To learn more about TVMDL’s test offerings and services, visit tvmdl.tamu.edu or call 1.888.646.5623.