Abstract
Internal nematode parasites, specifically the abomascal trichostrongyle Haemonchus spp., are a significant health concern in domestic and exotic ruminants in the southeastern U.S. and abroad.1-3 Non-chemical alternatives should be investigated in exotic species, similar to domestic ruminant studies, to reduce traditional drug selection pressure and address resistance issues. The nematophagous fungus, Duddingtonia flagrans, has shown promise in domestic small ruminants for environmental control of the infective L3 larvae in the feces in the environment.3 Two pilot trials were conducted to evaluate a non-chemical method for controlling gastrointestinal nematode parasites in captive ruminant hoof stock at Disney’s Animal Kingdom® and Disney’s Animal Kingdom Lodge®. The specific trials involved feeding spores of the nematode-trapping fungus Duddingtonia flagrans to selected captive exotic hoof stock in order to reduce infective larvae survival/development in feces and, thus, reduce exhibit forage contamination. The fungal spores were fed daily at 250,000 spores/kg BW for five days (2010 pilot trial) and 30,000 spores/kg BW for five days (2011 pilot trial). Fecal samples were collected from control and treatment animals before, during, and after the fungus treatment course to look at fecal egg counts and larval culture rates. Both doses showed successful reduction in survival of L3 larvae in vitro implying that doses of 30,000 spores/kg BW may be an effective tool for environmental control of Haemonchus spp. in exotic rtiodactylids.
Acknowledgments
The authors thank the AAZV Mazuri Grant fund for partial financial support of this project. We would also like to thanks the technicians and husbandry teams at Disney’s Animal Kingdom® and Disney’s Animal Kingdom Lodge® for their tireless hours of fecal collection and processing to make this project possible as well as the technical support team at Louisiana State University and International Health Products (Huntington, NSW, 2148, AU) sample processing and testing and for fungus supply respectively.
Literature Cited
1. Fontenot, DK, Miller, JE. 2010. Alternatives for Gastrointestinal Parasite Control in Exotic Ruminants In: Fowler, M. E., and R.E. Miller (Eds.). Zoo & Wild Animal Medicine, 7th ed. W. B. Saunders Co., Philadelphia, Pennsylvania. 581–588.
2. Fontenot, M., Miller, M., Peña, M., Larsen, M., Gillespie, A. 2003. Efficiency of feeding Duddingtonia flagrans chlamydospores to grazing ewes on reducing availability of parasitic nematode larvae on pasture. Vet. Parasitol. 118 (2003) 203–213.
3. Terrill, T., Larsen, M., Samples, O., Husted, S., Miller, J., Kaplan, R., Gelaye, S. 2004. Capability of the nematode-trapping fungus Duddingtonia flagrans to reduce infective larvae of gastrointestinal nematodes in goat feces in the southeastern United States: dose titration and dose time interval studies. Vet. Parasitol. 120 (2004) 285–296.