Hostname: page-component-586b7cd67f-g8jcs Total loading time: 0 Render date: 2024-11-22T19:31:43.808Z Has data issue: false hasContentIssue false
  • English
  • Français

Genetic parameters for resistance to nematode infections in Texel lambs and their utility in breeding programmes

Published online by Cambridge University Press:  18 August 2016

S. C. Bishop ,
F. Jackson ,
R. L. Coop  and
M. J. Stear
S. C. Bishop*
Affiliation:
Roslin Institute (Edinburgh), Roslin, Midlothian EH25 9PS, UK
F. Jackson
Affiliation:
Moredun Research Institute, Penicuik, Midlothian EH26 9PZ, UK
R. L. Coop
Affiliation:
Moredun Research Institute, Penicuik, Midlothian EH26 9PZ, UK
M. J. Stear
Affiliation:
Department of Veterinary Clinical Studies, Glasgow University Veterinary School, Bearsden Road, Glasgow G61 1QH, UK
*
†E-mail:[email protected]
Get access

Abstract

This paper addresses the inheritance of host resistance to gastro-intestinal nematode parasite infections in commercial Texel lambs, and the rôle of resistance to parasites in breeding programmes. In two flocks of Texel sheep, faecal egg counts following natural parasite challenge were measured on up to three occasions post weaning per lamb over a 4-year period, with 1385 and 287 lambs measured on the two farms. Live weight, and ultrasonically measured fat and muscle depth at weaning were available for each lamb, as were deep pedigrees. Egg counts were moderately to strongly heritable on all occasions, with Nematodirus egg counts more heritable than the Strongyle egg counts. Weighted average heritabilities for Strongyle and Nematodirus egg counts were 0.26 and 0.38, respectively. Within the same category of parasite, genetic correlations across time were positive and strong but somewhat less than unity, as were the correlations between Strongyle and Nematodirus egg counts measured at the same time. Genetic correlations between performance traits and Strongyle egg counts were usually favourable (i.e. negative) but weak, whereas those with Nematodirus egg counts were generally neutral or slightly positive. Whilst Nematodirus resistance may not necessarily be included in a breeding goal, the results suggest that Nematodirus egg counts can be used as an additional genetic indicator of Strongyle egg counts, at little extra cost. Including the epidemiological consequences of decreasing Strongyle egg counts in benefits of increasing parasite resistance, it is suggested that under UK conditions selection goals that place equal emphasis on live weight and log-transformed egg counts will be a robust means of improving growth rate and decreasing parasite larval challenge.

Keywords

faecal egg countsgenetic parametersNematodirussheepTeladorsagia
Type
Breeding and genetics
Information
Animal Science , Volume 78 , Issue 2 , April 2004 , pp. 185 - 194
Copyright
Copyright © British Society of Animal Science 2004

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Amer, P. R., Woolaston, R. R., Eady, S. J. and McEwan, J. C. 1999. Economic values for sheep internal parasite resistance traits in New Zealand and Australia. Proceedings of the Association for the Advancement of Animal Breeding and Genetics 13: 504–507.Google Scholar
Baker, R. L., Mugambi, J. M., Audho, J. O., Carles, A. B. and Thorpe, W. 2002. Comparison of Red Maasai and Dorper sheep for resistance to gastro-intestinal nematode parasites, productivity and efficiency in a sub-humid and a semi-arid environment in Kenya. Proceedings of the seventh world congress on genetics applied to livestock production, Montpellier, communication 13-10.Google Scholar
Barger, I. A. 1989. Genetic resistance of hosts and its influence on epidemiology. Veterinary Parasitology 32: 21-35.CrossRefGoogle ScholarPubMed
Bishop, S. C., Bairden, K., McKellar, Q. A., Park, M. and Stear, M. J. 1996. Genetic parameters for faecal egg count following mixed, natural, predominantly Ostertagia circumcincta infection and relationships with live weight in young lambs. Animal Science 63: 423–428.Google Scholar
Bishop, S. C. and Stear, M. J. 1997. Modelling responses to selection for resistance to gastro-intestinal parasites in sheep. Animal Science 64: 469–478.CrossRefGoogle Scholar
Bishop, S. C. and Stear, M. J. 1999. Genetic and epidemiological relationships between productivity and disease resistance: gastro-intestinal parasite infection in growing lambs. Animal Science 69: 515–524.Google Scholar
Bisset, S. A., Vlassof, A., Morris, C. A., Southey, B. R., Baker, R. L. and Parker, A. G. H. 1992. Heritability of and genetic correlations among faecal egg counts and productivity traits in Romney sheep. New Zealand Journal of Agricultural Research 35: 51–58.Google Scholar
Bouix, J., Krupinski, J., Rzepecki, R., Nowosad, B., Skrzyzala, I., Roborzynski, M., Fudalewicz-Niemczyk, W., Skalska, M., Malczewski, A. and Gruner, L. 1998. Genetic resistance to gastrointestinal nematode parasites in Polish long-wool sheep. International Journal for Parasitology 28: 1797–1804.Google Scholar
Christie, M. G. and Jackson, F. 1982. Specific identification of strongyle eggs in small samples of sheep faeces. Research in Veterinary Science 32: 113–117.CrossRefGoogle ScholarPubMed
Coop, R. L., Graham, R. B., Jackson, F., Wright, S.E. and Angus, K. W. 1985. Effect of experimental Ostertagia circumcincta infection on the performance of grazing lambs. Research in Veterinary Science 38: 282–287.Google Scholar
Coop, R. L., Sykes, A. R. and Angus, K. W. 1982. The effect of three levels of Ostertagia circumcincta larvae on growth rate, food intake and body composition of growing lambs. Journal of Agricultural Science, Cambridge 98: 247–255.Google Scholar
Douch, P. G. C., Green, R. S., Morris, C. A., Bisset, S. A., Vlassoff, A., Baker, R. L., Watson, T. G., Hurford, A. P. and Wheeler, M. 1995. Genetic and phenotypic relationships among anti-Trichostrongylus colubriformis antibody level, faecal egg count and body weight traits in grazing Romney sheep. Livestock Production Science 41: 121–132.Google Scholar
Eady, S. J., Woolaston, R. R., Lewer, R. R., Raadsma, H. W., Swan, A. A. and Ponzoni, R. W. 1998. Resistance to gastrointestinal parasites in Merino sheep: correlation with production traits. Australian Journal of Agricultural Research 49: 1201–1211.Google Scholar
Eady, S. J., Woolaston, R. R., Mortimer, S. I., Lewer, R. P., Raadsma, H. W., Swan, A. A. and Ponzoni, R. W. 1996. Resistance to nematode parasites in Merino sheep: sources of genetic variation. Australian Journal of Agricultural Research 47: 895–915.CrossRefGoogle Scholar
Gasbarre, L. C. and Miller, J. E. 2000. Genetics of helminth resistance. In Breeding for disease resistance in farm animals, second edition (ed. Axford, R. F. E., Bishop, S. C., Nicholas, F. W. and Owen, J. B.), pp. 129–152. CABI Publishing, Wallingford.Google Scholar
Gilmour, A. R., Thompson, R., Cullis, B. R. and Welham, S. 1996. ASREML. Biometrics bulletin no. 3, NSW Agriculture.Google Scholar
Gruner, L., Cortet, J., Sauve, C., Limouzin, C. and Brunel, J. C. 2002. Evolution of nematode community in grazing sheep selected for resistance and susceptibility to Teladorsagia circumcincta and Trichostrongylus colubriformis: a 4-year experiment. Veterinary Parasitology 109: 277–291.Google Scholar
Gruner, L. and Lantier, F. 1995. Breeding for resistance to infectious diseases in small ruminants in Europe. In Breeding for resistance to infectious diseases in small ruminants (ed Gray, G. D., Woolaston, R.R. and Eaton, B. T.). ACIAR, Canberra.Google Scholar
Jackson, F. and Coop, R. L. 2000. The development of anthelmintic resistance in sheep nematodes. Parasitology 120: S95-S107.CrossRefGoogle ScholarPubMed
Lawes Agricultural Trust. 1983. GENSTAT a general statistical program. Numerical Algorithms Group, Rothamsted Experimental Station, Harpenden.Google Scholar
Leathwick, D. M., Atkinson, D. S., Miller, C. M., Brown, A. E. and Sutherland, I. A. 2002. Benefits of reduced larval challenge through breeding for low faecal egg count in sheep. Novel approaches. III. A workshop meeting on helminth control in livestock in the new millennium, Moredun Research Institute, 2-5 July, 2002, p. 10.Google Scholar
McEwan, J. C., Dodds, K. G., Greer, G. J., Bain, W. E., Duncan, S. J., Wheeler, R., Knowler, K. J., Reid, P. J., Green, R. S. and Douch, P. G. C. 1995. Genetic estimates for parasite resistance traits in sheep and their correlations with production traits. New Zealand Journal of Zoology 22: 177.Google Scholar
McEwan, J. C., Mason, P., Baker, R. L., Clarke, J. N., Hickey, S. M. and Turner, K. 1992. Effect of selection for productive traits on internal parasite resistance in sheep. Proceedings of the New Zealand Society of Animal Production 52: 53–56.Google Scholar
Morris, C. A., Vlassoff, A., Bisset, S. A., Baker, R. L., Watson, T. G., West, C. J. and Wheeler, M. 2000. Continued selection of Romney sheep for resistance or susceptibility to nematode infection: estimates of direct and correlated responses. Animal Science 70: 17–27.CrossRefGoogle Scholar
Morris, C. A., Vlassof, A., Bisset, S. A., Baker, R. L., West, C. J. and Hurford, A. P. 1997. Responses of Romney sheep to selection for resistance or susceptibility to nematode infection. Animal Science 64: 319–329.Google Scholar
Perry, B. D., McDermott, J. J., Randolph, T. F., Sones, K. R. and Thornton, P. K. 2002. Investing in animal health research to alleviate poverty. International Livestock Research Institute, Nairobi, Kenya.Google Scholar
Simm, G. and Dingwall, W. S. 1989. Selection indices for lean meat production in sheep. Livestock Production Science 21: 223–233.CrossRefGoogle Scholar
Smith, J. A., Wilson, K., Pilkington, J. G. and Pemberton, J. M. 1999. Heritable variation in resistance to gastrointestinal nematodes in an unmanaged mammal population. Proceedings of the Royal Society of London, Series B-Biological Sciences 266: 1283–1290.Google Scholar
Sreter, T., Kasaai, T. and Takacs, E. 1994. The heritability and specificity of responsiveness to infections with Haemonchus contortus in sheep. International Journal for Parasitology 24: 871–876.Google Scholar
Stear, M. J., Bairden, K., Bishop, S. C., Gettinby, G., McKellar, Q. A., Park, M., Strain, S. and Wallace, D. S. 1998. The processes influencing the distribution of parasitic nematodes amongst naturally infected lambs. Parasitology 117: 165–171.CrossRefGoogle Scholar
Stear, M. J., Bishop, S. C., Bairden, K., Duncan, J. L., Gettinby, G., Holmes, P. H., McKellar, Q. A., Park, M., Strain, S. and Murray, M. 1997. The heritability of worm burden and worm fecundity in lambs following natural nematode infection. Nature 389: 27.CrossRefGoogle Scholar
Waller, P. J. 1997. Anthelmintic resistance. Veterinary Parasitology 72: 391–405.Google Scholar
Woolaston, R. R. 1994. Preliminary evaluation of strategies to breed Merinos for resistance to roundworms. Proceedings of the fifth world congress on genetics applied to livestock production, Guelph, vol. 20 , pp. 281–284.Google Scholar
Woolaston, R. R. and Piper, L. R. 1996. Selection of Merino sheep for resistance to Haemonchus contortus: genetic variation. Animal Science 62: 451–460.CrossRefGoogle Scholar
Woolaston, R. R. and Windon, R. G. 2001. Selection of sheep for response to Trichostrongylus colubriformis larvae: genetic parameters. Animal Science 73: 41–48.Google Scholar