High heritability for Ascaris and Trichuris infection levels in pigs

P. Nejsum, A. Roepstorff, C. B. Jørgensen, M. Fredholm, H. H.H. Göring, T. J.C. Anderson, S. M. Thamsborg

    Research output: Contribution to journalArticlepeer-review

    37 Scopus citations

    Abstract

    Aggregated distributions of macroparasites within their host populations are characteristic of most natural and experimental infections. We designed this study to measure the amount of variation that is attributable to host genetic factors in a pig-helminth system. In total, 195 piglets were produced after artificial insemination of 19 sows (Danish Landrace-Yorkshire crossbreds) with semen selected from 13 individual Duroc boars (1 or 2 sows per boar; mean litter size: 10.3; 5-14 piglets per litter). Starting at 10 weeks of age, piglets were repeatedly infected with the gastrointestinal helminths Trichuris suis and Ascaris suum by administering eggs in the feed for 14 weeks until necropsy. Faecal egg counts (FECs) were estimated regularly and A. suum worm burden was obtained at necropsy. Heritability calculations for log (FEC+1) at weeks 7-10 post-infection (p.i.) showed that 0.32-0.73 of the phenotypic variation for T. suis could be attributed to genetic factors. For A. suum, heritabilities of 0.29-0.31 were estimated for log (FEC+1) at weeks 7-14 p.i., whereas the heritability of log worm counts was 0.45. Strong positive genetic correlations (0.75-0.89) between T. suis and A. suum FECs suggest that resistance to both infections involves regulation by overlapping genes. Our data demonstrate that there is a strong genetic component in resistance to A. suum and T. suis infections in pigs. Identification of responsible genes would enhance our understanding of the host immune response to these common nematodes and for the closely related species (T. trichiura and A. lumbricoides) in man infecting more than a billion people.

    Original languageEnglish (US)
    Pages (from-to)357-364
    Number of pages8
    JournalHeredity
    Volume102
    Issue number4
    DOIs
    StatePublished - Apr 2009

    Keywords

    • Ascaris suum
    • Breeding
    • Heritability
    • Host genotypes
    • Resistance
    • Trichuris suis

    ASJC Scopus subject areas

    • Genetics
    • Genetics(clinical)

    Fingerprint Dive into the research topics of 'High heritability for Ascaris and Trichuris infection levels in pigs'. Together they form a unique fingerprint.

    Cite this