More Than Just A Fluke: Is the Air Sac Trematode (Family Cyclocoelidae) More Prevalent in Zoological Aviaries than Previously Thought?
American Association of Zoo Veterinarians Conference 2007
Elizabeth E. Hammond1, DVM; Dawn Zimmerman2, DVM; Drury Reavill3, DVM, DABVP, DACVP; Ben Okimoto4, DVM; Ellis Greiner5, PhD; Thomas M. Craig6, DVM, PhD; Norman O. Dronen7, PhD
1Lion Country Safari, Loxahatchee, FL, USA; 2Memphis Zoo, Memphis, TN, USA; 3Zoo/Exotic Pathology Service, West Sacramento, CA, USA; 4Honolulu Zoo, Honolulu, HI, USA; 5College of Veterinary Medicine, University of Florida, Gainesville, FL, USA; 6Department of Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, TX, USA; 7Laboratory of Parasitology, Department of Wildlife & Fisheries Sciences and the Schubot Center, Texas A&M University College Station, TX, USA
A novel species of trematode (Szidatitrema yamagutii, Family Cyclocoelidae) was identified in the air sacs of a deceased bearded barbet (Lybius dubius) and a white necked mynah (Streptocitta albicollis) from an indoor aviary at a zoo in Louisiana. A similar air sac trematode (Family Cyclocoelidae) was found post mortem in two Indian Hill mynahs from a zoological facility in Hawaii. At a zoo in Tennessee, a similar trematode (Family Cyclocoelidae) has been seen in ten different species of birds from an indoor aviary. Antemortem diagnosis is challenging. Routine fecal examination is often negative, although sedimentation can increase the likelihood of finding the parasite eggs. The most reliable antemortem test is endoscopy to visualize adult trematodes. Various treatment regimens have been attempted with variable success. These include injectable and nebulized praziquantel and manual removal of parasites from air sacs. Because the trematode completes its life cycle using a snail intermediate host, control of this invertebrate is also important for reducing the parasite burden. This parasite may be more prevalent in captive birds than previously thought and opportunistic screening of birds is recommended.