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Guilherme Gomes Verocai Supervisor: Susan Kutz

Life History of the ‘Serendipity worm’ ( Nematoda : Protostrongylidae ): an undescribed parasite of ungulates in the Arctic and Subarctic. Guilherme Gomes Verocai Supervisor: Susan Kutz. Parasites can act as drivers of ecological changes in host populations

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Guilherme Gomes Verocai Supervisor: Susan Kutz

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  1. Life History of the ‘Serendipity worm’ (Nematoda: Protostrongylidae): an undescribed parasite of ungulates in the Arctic and Subarctic Guilherme Gomes Verocai Supervisor: Susan Kutz

  2. Parasites can act as drivers of ecological changes in host populations Lack of knowledge on Arctic parasite diversity limits understanding Studies on parasites, their distribution, and impacts on host populations Economical and cultural importance Introduction Photo: Susan Kutz

  3. Introduction • An unknown Protostrongylidae species was discovered in ungulates across the Arctic(Kutz et al., 2007) Occurrence of Serendipity worm in North America (extracted from Kutz el al., 2007)

  4. Introduction • Larvae isolated from feces and molecularly characterized based on the ITS-2 sequence (2000-2006) • Distinct from other species within the Family Protostrongylidae • No taxonomical description was provided • Deroceras laeve (Müller, 1774): naturally infected intermediate host (IH)

  5. Introduction DH: site of parasitism? ? PPP=? days L3 emerges? L1 shed in feces Development from L1 to L3 = ?days ? IH Proposed life-cycle of the Serendipity worm. L1: First-stage larva, L3: Third-stage larva, IH: Intermediate Host, DH: Definitive Host, PPP: Pre-patent Period.

  6. Objectives • 1. Provide a taxonomic description • 2. Establish life cycle experimentally • 3. Determine definitive host and geographic ranges Photo: Pat Curry

  7. Methods • 1. Taxonomic description: • Muskoxen from Nunavik, QU • 1 post mortem + lungs of 2 hunted animals • Lung dissection • Several washes passing through 75μm sieve • Analyzed material at dissecting microscope

  8. Methods • Lung tissue for histopathology (10% buffer formalin) • Molecular confirmation of species identity (ITS-2) • Taxonomic description: • Clear nematodes with Lactophenol • Sp. description: measurements, drawings • Comparison with related spp.: Museum types • Phylogeny within Protostrongylidae based on morphology • Larval stages: L1 from feces/L2-3 from gastropods

  9. Preliminary Results • Collected material: nematodes in lungs * Body fragments containing taxonomic relevant features (i.e. cephalic and caudal ends) Male caudal end Cephalic end Female caudal end Embryonated egg

  10. Methods • 2. Establish life cycle experimentally : • Muskoxen fecal samples • Isolate L1 (Baermann technique) • Infect laboratory gastropods • Recover L3 by digestion

  11. Methods • 2. Establish life cycle experimentally : • Infect captive muskox (1) and reindeer (4-6) • Evaluate life cycle parameters (PPP, patent period, seasonality) • Infected animals will serve as larval source • Describe pathology in experimentally infected reindeer

  12. Preliminary Results • Larvae successfully developed in experimentally infected gastropods: • D. reticulatum: L3 in 52 days • Lymnaeastagnalis: L2 in few weeks • Larval emergence occurs • Muskox experimentally exposed to L3 • Fecal monitoring

  13. Methods • 3. Determine definitive host species and geographic ranges: • Fecal samples from northern ungulates (herds/populations) • Larval isolation by Baermann technique • Material from caribou herds and muskoxen frozen at -20C • Molecular identification based on ITS-2 sequence • Studies on Phylogeography (based on cox I of mDNA)

  14. Preliminary results

  15. Preliminary results Caribou herds infected by Serendipity worm Source: WWF/CARMA Network

  16. Preliminary Results • Caribou: • New records of infected herds in Canada mainland • Overlaps Parelaphostrongylusandersoni • Co-infections can occur • Prevalence in Muskoxen from Quebec • 86.7 – 100% (several collections 2008-10) • Greenland muskoxen & caribou: 0% • Elk from the Yukon: 0% (n=60)

  17. Summary ? ? ? ? ? ? DH: SITE OF PARASITISM PPP L1 shed in feces L3 emerges Development from L1 to L3 IH

  18. Summary ? ? ? ? ? DH: SITE OF PARASITISM PPP LUNGS L1 shed in feces L3 emerges Development from L1 to L3 IH

  19. Summary ? ? ? ? DH: SITE OF PARASITISM PPP LUNGS 52 days L1 shed in feces L3 emerges Development from L1 to L3 IH

  20. Summary ? ? ? DH: SITE OF PARASITISM PPP LUNGS 52 days L1 shed in feces L3 emerges Development from L1 to L3 IH

  21. Summary ? ? DH: SITE OF PARASITISM PPP LUNGS 52 days L1 shed in feces L3 emerges Development from L1 to L3 IH

  22. Kutz Lab: Dean Brown, Danna Schock, Nathan deBruyn, Pat Curry, Bryanne Hoar, Ryan Brook, Jesse Invik, Lynn Klassen Committee: Susan Kutz, John Gilleard, Alessandro Massolo, Eric Hoberg Gilleard Lab: Alexander Eberhardt Lukowiak Lab: Sarah Dalesman Czub & Leguillette Labs Greg Muench, Nigel Caulkett, Marianne Jorgensen Makivik Corp: ManonSimard, Bill Doidge, François Martin Biologists and Veterinarians with Governments of NU, NT, YK, Alaska, and Greenland Northern communities/hunters Department of Ecosystem and Public Health Acknowledgements

  23. Thanks!

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