Parasitology Research

, Volume 101, Issue 1, pp 53–62 | Cite as

Epidemiology of hookworm (Uncinaria spp.) infection in New Zealand (Hooker’s) sea lion (Phocarctos hookeri) pups on Enderby Island, Auckland Islands (New Zealand) during the breeding seasons from 1999/2000 to 2004/2005

  • A. Castinel
  • P. J. Duignan
  • E. T. Lyons
  • W. E. Pomroy
  • N. Gibbs
  • N. López-Villalobos
  • B. L. Chilvers
  • I. S. Wilkinson
Original Paper


This is the first investigation of the epidemiology of hookworm (Uncinaria spp.) infection in New Zealand sea lions (NZSLs; Phocarctos hookeri) on Enderby Island, Auckland Islands. The examination of faeces for hookworm eggs in various age categories of sea lions revealed that only pups up to at least 3 months of age harboured adult hookworms in their intestines. Gross necropsy of more than 400 pups from 1999/2000 to 2004/2005 showed that the prevalence of hookworm infection varied significantly between years and was higher from mid-January to the end of February when the majority of pups were between 3 and 9 weeks old. The average burden of adult parasites per pup was not influenced by the host’s sex and body condition or by year. This study also provided evidence for transmission occurring by the transmammary route in NZSLs.



The authors would like to thank P. MacLelland, M. Brown, R. Hood, and H. Best for helping in the collection of the dead pups in the field, and J. Amey, F. Gulland, M. Stratton, F. Riet-Sapriza, S. Childerhouse, and W. Hockley for conducting and/or assisting with the necropsies. The authors also acknowledge B. Adlington and A. Tunnicliffe from the Laboratory of Parasitology, IVABS (Massey University), S. Tolliver (Gluck Equine Research Center, University of Kentucky) for editing the present manuscript, and Pr V. Neall (Earth and Soil Science, Massey University) and B. Clothier (HortResearch, Palmerston North) for their help with the soil studies. The approval for this work was obtained from the New Zealand Department of Conservation (DOC) and Massey University Animals Ethics Committee, and research was conducted under the permit from DOC. This study was partly funded by the Institute of Veterinary, Animal and Biomedical Sciences (Massey University, Palmerston North, New Zealand), with the Novartis scholarship in Veterinary Parasitology and the Joan Berry scholarship in Veterinary Science and by DOC.


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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • A. Castinel
    • 1
  • P. J. Duignan
    • 1
  • E. T. Lyons
    • 2
  • W. E. Pomroy
    • 1
  • N. Gibbs
    • 3
  • N. López-Villalobos
    • 1
  • B. L. Chilvers
    • 4
  • I. S. Wilkinson
    • 4
  1. 1.New Zealand Wildlife Health Centre, Institute of Veterinary, Animal and Biomedical ScienceMassey UniversityPalmerston NorthNew Zealand
  2. 2.Department of Veterinary ScienceUniversity of Kentucky, Gluck Equine Research CenterLexingtonUSA
  3. 3.Department of ConservationWellingtonNew Zealand
  4. 4.Marine Conservation UnitDepartment of ConservationWellingtonNew Zealand

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