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Alternatives to anthelmintics for the control of nematodes in livestock

  • M. J. STEAR (a1), M. DOLIGALSKA (a2) and K. DONSKOW-SCHMELTER (a2)
Abstract

Efficient and welfare-friendly livestock production demands the control of nematode infection. Current control measures rely upon anthelmintic treatment but are threatened by the widespread evolution of drug-resistance in parasite populations. Several methods have been advocated to control nematodes without relying on effective anthelmintics. These include grazing management, biological control, nutritional supplementation, vaccination, and genetic approaches. Each method has its advantages and disadvantages. There are several grazing management schemes that can reduce the severity of infection but they are insufficient on their own to control infection. Biological control includes the use of predatory fungi to control nematode populations and the use of pasture species that can reduce the intensity of infection. Fungi can control nematodes but the current requirement for daily feeding means that this approach will be most useful for animals that are handled daily. Feeding supplementary protein can control nematode infection. The method is simple but can be expensive and may not be cost-effective for some marginal enterprises. Genetic approaches include the use of resistant breeds and selective breeding. Some breeds will thrive in conditions that kill animals from other breeds but substitution of resistant breeds is not always feasible. Selective breeding is effective and inexpensive but requires a high level of expertize. The most appropriate method or set of methods to minimize the adverse consequences of nematode infection may vary among farms.

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Corresponding author
Veterinary Genes and Proteins Group, Institute of Comparative Medicine, University of Glasgow, Bearsden Road, Glasgow G61 1QH, UK. Tel: +44 141 330 5762. Fax: +44 141 942 7215. E-mail: m.j.stear@vet.gla.ac.uk
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REFERENCES

Abbott, E. M., Parkins, J. J. and Holmes, P. H. ( 1984). Studies on the pathophysiology of chronic ovine haemonchosis in Merino and Scottish Blackface lambs. Parasitology 89, 585596.
Abbott, E. M., Parkins, J. J. and Holmes, P. H. ( 1985). Influence of dietary protein on parasite establishment and pathogenesis in Finn Dorset and Scottish Blackface lambs given a single moderate infection of Haemonchus contortus. Research in Veterinary Science 38, 613.
Abbott, E. M., Parkins, J. J. and Holmes, P. H. ( 1986). The effect of dietary protein on the pathogenesis of acute ovine haemonchosis. Veterinary Parasitology 20, 275289.
Abbott, E. M., Parkins, J. J. and Holmes, P. H. ( 1988). Influence of dietary protein on the patho-physiology of haemonchosis in lambs given continuous infections. Research in Veterinary Science 45, 4149.
Abbott, E. M., Parkins, J. J. and Holmes, P. H. ( 2000). Influence of dietary protein on the pathophysiology of ovine haemonchosis in Finn Dorset and Scottish Blackface lambs given a single moderate infection. Research in Veterinary Science 38, 5460.
Albers, G. A. A., Gray, G. D., Piper, L. R., Barker, J. S. F., Lejambre, L. and Barger, I. A. ( 1987). The genetics of resistance and resilience to Haemonchus contortus infection in young Merino sheep. International Journal for Parasitology 17, 13551363.
Armour, J., Jarrett, W. F. H. and Jennings, F. W. ( 1966). Experimental Ostertagia circumcincta infections in sheep: Development and pathogenesis of a single infection. American Journal of Veterinary Research 27, 12671278.
Bahirathan, M., Miller, J. E., Barras, S. R. and Kearney, M. T. ( 2000). Variation in susceptibility of Suffolk and Gulf Coast Native suckling lambs to naturally acquired strongylate nematode infections. Veterinary Parasitology 65, 259268.
Bain, R. K. ( 1999). Irradiated vaccines for helminth control in livestock. International Journal for Parasitology 29, 185191.
Baker, R. L., Mwamachi, D. M., Audho, J. O., Aduda, E. O. and Thorpe, W. ( 1999). Genetic resistance to gastro-intestinal nematode parasites in Red Maasai, Dorper and Red Maasai×Dorper ewes in the sub-humid tropics. Animal Science 69, 335344.
Baker, R. L., Nagda, S., Rodriguez-Zas, S. L., Southey, B. R., Audho, J. O., Aduda, E. O. and Thorpe, W. ( 2003). Resistance and resilience to gastro-intestinal nematode parasites and relationships with productivity of Red Maasai, Dorper and Red Maasai×Dorper crossbred lambs in the sub-humid tropics. Animal Science 76, 119136.
Bartley, D. J., Jackson, F., Jackson, E. and Sargison, N. ( 2004). Characterisation of two triple resistant field isolates of Teladorsagia from Scottish lowland sheep farms. Veterinary Parasitology 123, 189199.
Beh, K. J., Hulme, D. J., Callaghan, M. J., Leish, Z., Lenane, I., Windon, R. G. and Maddox, J. F. ( 2002). A genome scan for quantitative trait loci affecting resistance to Trichostrongylus colubriformis in sheep. Animal Genetics 33, 97106.
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 liveweight in young lambs. Animal Science 63, 423428.
Bishop, S. C. and Stear, M. J. ( 1997). Modelling responses to selection for resistance to gastro-intestinal parasites in sheep. Animal Science 64, 469478.
Bishop, S. C. and Stear, M. J. ( 2000). The use of a gamma-type function to assess the relationship between the number of adult Teladorsagia circumcincta and total egg output. Parasitology 121, 435440.
Bisset, S. A., Vlassoff, 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, 5158.
Bizzell, W. E. and Ciordia, H. ( 1965). Dissemination of infective larvae of trichostrongylid parasites of ruminants from feces to pasture by the fungus, Pilobolus spp. Journal of Parasitology 51, 184.
Blattman, A. N., Hulme, D. J., Kinghorn, B. P., Woolaston, R. R., Gray, G. D. and Beh, K. J. ( 1993). A search for associations between major histocompatibility complex restriction fragment length polymorphism bands and resistance to Haemonchus contortus infection in sheep. Animal Genetics 24, 277282.
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, 17971804.
Bown, M. D., Poppi, D. P. and Sykes, A. R. ( 1991). The effect of post-ruminal infusion of protein or energy on the pathophysiology of Trichostrongylus colubriformis infection and body composition in lambs. Australian Journal of Agricultural Research 42, 253267.
Callinan, A. P. L. ( 1978). The ecology of the free-living stages of Ostertagia circumcincta. International Journal for Parasitology 8, 233237.
Callinan, A. P. L., Morley, F. H. W., Arundel, J. H. and White, D. H. ( 1982). A model of the life cycle of sheep nematodes and the epidemiology of nematodiasis in sheep. Agricultural Systems 9, 199225.
Charon, K. M., Moskwa, B., Rutkowski, R., Gruszczynska, J. and Swiderek, W. ( 2002). Microsatellite polymorphism in DRB1 gene (MHC class II) and its relation to nematode faecal egg count in Polish Heath Sheep. Journal of Animal and Feed Sciences 11, 4758.
Clunies Ross, I. ( 1932). Observations on the resistance of sheep to infestation by the stomach worm (Haemonchus contortus). Journal of the Council for Scientific and Industrial Research, Australia 5, 7380.
Coltman, D. W., Wilson, K., Pilkington, J., Stear, M. J. and Pemberton, J. M. ( 2001). A microsatellite polymorphism in the gamma interferon gene is associated with resistance to gastrointestinal nematodes in a naturally-parasitized population of Soay sheep. Parasitology 122, 571582.
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, 282287.
Coop, R. L., Huntley, J. F. and Smith, W. D. ( 1995). Effect of dietary-protein supplementation on the development of immunity to Ostertagia circumcincta in growing lambs. Research in Veterinary Science 59, 2429.
Coop, R. L. and Kyriazakis, I. ( 2000). Influence of host nutrition on the development and consequences of parasitism in livestock. Parasitology Today 17, 325330.
Coop, R. L. and Kyriazakis, I. ( 2001). Influence of host nutrition on the development and consequences of parasitism in livestock. Trends in Parasitology 17, 325330.
Coop, R. L., Sykes, A. R. and Angus, K. W. ( 1977). The effect of a daily intake of Ostertagia circumcincta larvae on body weight, food intake and concentration of serum constituents in sheep. Research in Veterinary Science 23, 7683.
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, 247255.
Cooper, D. W., van Oorschot, R. A. H., Piper, L. R. and LeJambre, L. F. ( 1989). No association between the ovine leucocyte antigen (OLA) system in the Australian Merino and susceptibility to Haemonchus contortus infection. International Journal for Parasitology 19, 695697.
Crawford, A., McEwan, J. C., Dodds, K. G., Wright, C. S., Bisset, S. A., Macdonald, P. A., Knowler, K. J. J., Greer, G. J., Green, R. S., Shaw, R. J., Paterson, K. A., Cuthbertson, R. P., Vlassoff, A., Squire, D. R., West, C. J. and Phua, S. H. ( 1997). Resistance to nematode parasites in sheep: How important are the MHc genes? Proceedings of the Association for the Advancement of Animal Breeding and Genetics 12, 5862.
Dalton, J. P., Brindley, P. J., Knox, D. P., Brady, C. P., Hotez, P. J., Donnelly, S., O'Neill, S. M., Mulcahy, G. and Loukas, A. ( 2003). Helminth vaccines: from mining genomic information for vaccine targets to systems used for protein expression. International Journal for Parasitology 33, 621640.
Doligalska, M., Moskwa, B. and Stear, M. J. ( 1999). Relationships among peripheral eosinophilia, eosinophil peroxidase activity, interleukin-5 concentration and faecal nematode egg count during natural, mixed gastrointestinal nematode infection. Veterinary Immunology and Immunopathology 70, 299308.
Dominik, S. ( 2005). Quantitative trait loci for internal nematode resistance in sheep: a review. Genetics, Selection, Evolution 37 (Suppl. 1), S83S96.
Donald, A. D., Morley, F. H. W., Waller, P. J., Axelsen, A., Dobson, R. J. and Donnelly, J. R. ( 1982). Effects of reproduction, genotype and anthelmintic treatment of ewes on Ostertagia spp. populations. International Journal for Parasitology 12, 403411.
Donaldson, J., van Houtert, M. F. J. and Sykes, A. R. ( 1998). The effect of nutrition on the periparturient parasite status of mature ewes. Animal Science 67, 523533.
Douch, P. G. C., Green, R. S., Morris, C. A., McEwan, J. C. and Windon, R. G. ( 1996). Phenotypic markers for selection of nematode-resistant sheep. International Journal for Parasitology 26, 899911.
Eady, S. J., Woolaston, R. R., Lewer, R. P., Raadsma, H. W., Swan, A. A. and Ponzoni, R. W. ( 1998). Resistance to nematode parasites in Merino sheep: correlation with production traits. Australian Journal of Agricultural Science 49, 12011211.
Emery, D. L. ( 1996). Vaccination against worm parasites of animals. Veterinary Parasitology 64, 3145.
Gamble, H. R. and Zajac, A. M. ( 1992). Resistance of St. Croix lambs to Haemonchus contortus in experimentally and naturally acquired infections. Veterinary Parasitology 41, 211225.
Gettinby, G., Armour, J., Bairden, K. and Plenderleith, R. W. J. ( 1987). A survey by questionaire of parasitic worm control in cattle and sheep at the Glasgow University Lanark practice. Veterinary Record 121, 487490.
Gettinby, G., McKellar, Q. A., Bairden, K., Theodoridis, Y. and Whitelaw, A. ( 1985). Comparison of two techniques used for the recovery of nematode infective larvae from pasture. Research in Veterinary Science 39, 99102.
Gibbs, H. C. and Barger, I. A. ( 1986). Haemonchus contortus and other trichostrongylid infections in parturient, lactating and dry ewes. Veterinary Parasitology 22, 5766.
Gibson, T. E. and Everett, G. ( 1972). The ecology of the free-living stages of Ostertagia circumcincta. Parasitology 64, 451460.
Good, B., Hanrahan, J. P., Crowley, B. A. and Mulcahy, G. ( 2006). Texel sheep are more resistant to natural, nematode challenge than Suffolk sheep based on faecal egg count and worm burden. Veterinary Parasitology 136, 317327.
Gorski, P., Niznikowski, R., Popielarczyk, D., Strzelec, E., Gajewska, A. and Wedrychowicz, H. ( 2006). Natural parasitic infections in various breeds of sheep in Poland. Archiv für Tierzucht Dummerstorf 47, 5055.
Gray, G. D., Presson, B. L., Albers, G. A. A., Le Jambre, L. F., Piper, L. R. and Barker, J. S. F. ( 1987). Comparison of within- and between-breed variation in resistance to haemonchosis in sheep. In Merino Improvement Programmes in Australia (ed. MCGuirk, B. J.), pp. 365369. Australian Wool Corporation, Melbourne, Australia.
Gruner, L., Aumont, G., Bouix, J. and Mandonnet, N. ( 2001). The genetic resistance to nematode parasites in small ruminants: a more and more well known trait. (In French.) 8emes Rencontres autour des Recherches sur les Ruminants, Paris, France, 5–6 Decembre 2001.
Hein, W. R., Shoemaker, C. B. and Heath, A. G. C. ( 2001). Future technologies for control of nematodes in sheep. New Zealand Veterinary Journal 49, 247251.
Hilderson, H., De Graaf, D. C., Vercruysse, J. and Berghen, P. ( 1993). Characterisation of Ostertagia ostertagi antigens by the different bovine immunoglobulin isotypes. Research in Veterinary Science 55, 203208.
Houdijk, J. G. M., Kyriazakis, I., Coop, R. L. and Jackson, F. ( 2001 a). The expression of immunity to Teladorsagia circumcincta in ewes and its relationship to protein nutrition depend on body protein reserves. Parasitology 122, 661672.
Houdijk, J. G. M., Kyriazakis, I., Jackson, F. and Coop, R. L. ( 2001 b). The relationship between protein nutrition, reproductive effort and breakdown in immunity to Teladorsagia circumcincta in periparturient ewes. Animal Science 72, 595606.
Houdijk, J. G. M., Kyriazakis, I., Jackson, F., Huntley, J. F. and Coop, R. L. ( 2003). Is the allocation of metabolisable protein prioritised to milk production rather than to immune functions in Teladorsagia circumcincta-infected lactating ewes? International Journal for Parasitology 33, 327338.
Hulme, D. J., Nicholas, F. W., Windon, R. G., Brown, S. C. and Beh, K. J. ( 1993). The MHC class II region and resistance to an intestinal parasite in sheep. Journal of Animal Breeding and Genetics 110, 459472.
Israf, D. A., Coop, R. L., Stevenson, L. M., Jones, D. G., Jackson, F., Jackson, E., MacKellar, A. and Huntley, J. F. ( 1996). Dietary protein influences upon immunity to Nematodirus battus infection in lambs. Veterinary Parasitology 61, 273286.
Jackson, F., Jackson, E. and Williams, J. T. ( 1988). Susceptibility of the pre-parturient ewe to infection with Trichostrongylus vitrinus and Ostertagia circumcincta. Research in Veterinary Science 45, 213218.
Jorgensen, L. T., Leathwick, D. M., Charleston, W. A. G., Godfrey, P. L., Vlassoff, A. and Sutherland, I. A. ( 1998). Variation between hosts in the developmental success of the free-living stages of trichostrongyle infections of sheep. International Journal for Parasitology 28, 13471352.
Kahn, L. P., Knox, M. R. and Gray, G. D. ( 1999). Enhancing immunity to nematode parasites in pregnant and lactating sheep through nutrition and genetic selection. Recent Advances in Animal Nutrition in Australia 12, 1522.
Kambara, T., McFarlane, R. G., Abell, T. J., McAnulty, R. W. and Sykes, A. R. ( 1993). The effect of age and dietary protein on immunity and resistance in lambs vaccinated with Trichostrongylus colubriformis. International Journal for Parasitology 23, 471476.
Kao, R. R., Leathwick, D. M., Roberts, M. G. and Sutherland, I. A. ( 2000). Nematode parasites of sheep: a survey of epidemiological parameters and their application in a simple model. Parasitology 121, 85103.
Kloosterman, A., Albers, G. A. A. and van den Brink, R. ( 1978). Genetic variation among calves in resistance to nematode parasites. Veterinary Parasitology 4, 353368.
Knox, D. P. ( 2004). Technological advances and genomics in metazoan parasites. International Journal for Parasitology 34, 139152.
Knox, D. P., Redmond, D. L., Newlands, G. F., Skuce, P. J., Pettit, D. and Smith, W. D. ( 2003). The nature and prospects for gut membrane proteins as vaccine candidates for Haemonchus contortus and other ruminant trichostrongyloids. International Journal for Parasitology 33, 11291137.
Knox, M. R., Josh, P. F. and Anderson, L. J. ( 2002). Deployment of Duddingtonia flagrans in an improved pasture system: dispersal, persistence, and effects on free-living soil nematodes and microarthropods. Biological Control 24, 176182.
Knox, M. R. and Steel, J. W. ( 1999). The effects of urea supplementation on production and parasitological responses of sheep infected with Haemonchus contortus and Trichostrongylus colubriformis. Veterinary Parasitology 83, 123135.
Koski, K. G. and Scott, M. E. ( 2003). Gastrointestinal nematodes, trace elements, and immunity. Journal of Trace Elements in Experimental Medicine 16, 237251.
Kyriazakis, I., Anderson, D. H., Coop, R. L. and Jackson, F. ( 1996). The pathophysiology and development of immunity during long-term subclinical infection with Trichostrongylus colubriformis of sheep receiving different nutritional treatments. Veterinary Parasitology 65, 4154.
Leighton, E. A., Murrell, K. D. and Gasbarre, L. C. ( 1989). Evidence for genetic control of nematode egg-shedding rates in calves. Journal of Parasitology 75, 498504.
Leignel, V., Cabaret, J. and Humbert, J. F. ( 2002). New molecular evidence that Teladorsagia circumcincta (Nematoda: Trichostrongylidea) is a species complex. Journal of Parasitology 88, 135140.
Littledike, E. T. and Young, L. D. ( 1993). Effect of sire and dam breed on copper status of fat lambs. Journal of Animal Science 71, 774778.
Mackinnon, M. J., Meyer, K. and Hetzel, D. J. S. ( 1991). Genetic variation and covariation for growth, parasite resistance and heat tolerance in tropical cattle. Livestock Production Science 27, 105122.
Marley, C. L., Cook, R., Barrett, J., Keatinge, R., Lampkin, N. H. and McBride, S. D. ( 2003). The effect of dietary forage on the development and survival of helminth parasites in ovine faeces. Veterinary Parasitology 118, 93107.
McCririe, L., Bairden, K., Britton, C., Buitkamp, J., McKeand, J. B. and Stear, M. J. ( 1997). Heterogeneity in the recognition of Ostertagia circumcincta antigens by serum antibody from mature, infected sheep. Parasite Immunology 19, 235242.
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.
Meeusen, E. N. T. and Piedrafita, D. ( 2003). Exploiting natural immunity to helminth parasites for the development of veterinary vaccines. International Journal for Parasitology 33, 12851290.
Michel, J. F. ( 1985). Epidemiology and control of gastrointestinal helminths in domestic animals. In Chemotherapy of Gastrointestinal Helminths. Handbook of Experimental Pharmacology ( ed. van den Bossche, H., Thienpont, D. and Janssens, P. G.), 77, 67123. Springer-Verlag, Berlin.
Morris, C. A., Green, R. S., Cullen, N. G. and Hickey, S. M. ( 2003). Genetic and phenotypic relationships among faecal egg count, anti-nematode antibody level and live weight in Angus cattle. Animal Science 76, 167174.
Morris, C. A., Watson, T. G., Bisset, S. A., Vlassoff, A. and Douch, P. G. C. ( 2000). Breeding sheep in New Zealand for resistance or resilience to nematode parasites. 77–98. In Breeding for Resistance to Infectious Diseases of Small Ruminants. ( ed. Gray, G. D., Woolaston, R. R. and Eaton, B. D.) ACIAR Monograph No 34, Canberra, Australia.
Moskwa, B., Doligalska, M. and Cabaj, W. ( 1998). The repeatability of haematological and parasitological parameters in Polish Wrzosowka hoggets naturally infected with trichostrongylid nematodes. Acta Parasitologica 43, 148153.
Mugambi, J. M., Wanyangu, S. W., Bain, R. K., Owango, M. O., Duncan, J. L. and Stear, M. J. ( 1996). Response of Dorper and Red Maasai lambs to trickle Haemonchus contortus infections. Research in Veterinary Science 61, 218221.
Newton, S. E. and Munn, E. A. ( 1999). The development of vaccines against gastrointestinal nematode parasites, particularly Haemonchus contortus. Parasitology Today 15, 116122.
Nguti, R., Janssen, P., Rowlands, G. J., Audho, J. O. and Baker, R. L. ( 2003). Survival of Red maasai, Dorper and crossbred lambs in the sub-humid tropics. Animal Science 76, 317.
Nicholas, F. W. ( 1987). Veterinary Genetics. Oxford University Press, Oxford.
Nieuwhof, G. J. and Bishop, S. C. ( 2005). Costs of the major endemic diseases of sheep in Great Britain and the potential benefits of reduction in disease impact. Animal Science 81, 2329.
Niezen, J. H., Charleston, W. A. G., Hodgson, J., Mackay, A. D. and Leathwick, D. M. ( 1996). Controlling internal parasites in grazing ruminants without recourse to anthelmintics: approaches, experiences and prospects. International Journal for Parasitology 26, 983992.
Niezen, J. H., Charleston, W. A. G., Hodgson, J., Miller, C. M., Waghorn, T. S. and Robertson, H. A. ( 1998). Effect of plant species on the larvae of gastrointestinal nematodes which parasitise sheep. International Journal for Parasitology 28, 791803.
O'Sullivan, B. M. and Donald, A. D. ( 1973). Responses to infection with Haemonchus contortus and Trichostrongylus colubriformis in ewes of different reproductive staus. International Journal for Parasitology 3, 521530.
Parsonson, I. ( 1998). The Australian Ark. CSIRO Publishing, Collingwood.
Paterson, S., Wilson, K. and Pemberton, J. M. ( 1998). Major histocompatibility complex variation associated with juvenile survival and parasite resistance in a large unmanaged ungulate population (Ovis aries L.). Proceedings of the National Academy of Sciences, USA 95, 37143719.
Perry, B. D. and Randolph, T. F. ( 1999). Improving the assessment of the economic impact of parasitic diseases and of their control in production animals. Veterinary Parasitology 84, 145168.
Robinson, J. ( 1962). Pilobolus spp. and the translocation of the infective larvae of Dictyocaulus viviparus from faeces to pastures. Nature, London 193, 353354.
Sayers, G., Good, B., Hanrahan, J. P., Ryan, M., Angles, J. M. and Sweeney, T. ( 2005). Major histocompatibility complex DRB1 gene: its role in nematode resistance in Suffolk and Texel sheep breeds. Parasitology 131, 403409.
Sayers, G. and Sweeney, T. ( 2005). Gastrointestinal nematode infection in sheep – a review of the alternatives to anthelmintics in parasite control. Animal Health Research Reviews 6, 159171.
Schallig, H. D. F. H., van Leeuwen, M. A. W. and Hendrikx, W. M. L. ( 1994). Immune responses of Texel sheep to excretory/secretory products of adult Haemonchus contortus. Parasitology 108, 351357.
Schwaiger, F. W., Gostomski, D., Stear, M. J., Duncan, J. L., McKellar, Q. A., Epplen, J. T. and Buitkamp, J. ( 1995). An ovine major histocompatibility complex DRB1 allele is associated with low faecal egg counts following natural predominantly Ostertagia circumcincta infection. International Journal for Parasitology 25, 815822.
Simm, G. ( 1998). Genetic Improvement of Cattle and Sheep. Farming Press, Ipswich.
Smith, W. D. ( 1999). Prospects for vaccines of helminth parasites of grazing ruminants. International Journal for Parasitology 29, 1724.
Sreter, T., Kassai, T. and Takacs, E. ( 1994). The heritability and specificity of responsiveness to infection with Haemonchus contortus in sheep. International Journal for Parasitology 24, 871876.
Stear, M. J., Bairden, K., Bishop, S. C., Buitkamp, J., Duncan, J. L., Gettinby, G., McKellar, Q. A., Park, M., Parkins, J. J., Reid, S. W. J., Strain, S. A. J. and Murray, M. ( 1997). The genetic basis of resistance to Ostertagia circumcincta in lambs. The Veterinary Journal 154, 111119.
Stear, M. J., Bairden, K., Duncan, J. L., Eckersall, P. D., Fishwick, G., Graham, P. A., Holmes, P. H., McKellar, Q. A., Mitchell, S., Murray, M., Parkins, J. J. and Wallace, D. S. ( 2000 a). The influence of relative resistance and urea-supplementation on deliberate infection with Teladorsagia circumcincta during winter. Veterinary Parasitology 94, 4554.
Stear, M. J., Bairden, K., McKellar, Q. A., Scott, I. and Strain, S. A. J. ( 1999). The relationship between the number and size of nematodes in the abomasum and the concentration of pepsinogen in ovine plasma. Research in Veterinary Science 67, 8992.
Stear, M. J. and Bishop, S. C. ( 1999). The curvilinear relationship between worm length and fecundity of Teladorsagia circumcincta. International Journal for Parasitology 29, 777780.
Stear, M. J., Bishop, S. C., Doligalska, M., Duncan, J. L., Holmes, P. H., Irvine, J., McCririe, L., McKellar, Q. A., Sinski, E. and Murray, M. ( 1995). Regulation of egg production, worm burden, worm length and worm fecundity by host responses in sheep infected with Ostertagia circumcincta. Parasite Immunology 17, 643652.
Stear, M. J., Bishop, S. C., Henderson, N. G. and Scott, I. ( 2003). A key mechanism of pathogenesis in sheep infected with the nematode Teladorsagia circumcincta. Animal Health Research Reviews 4, 4552.
Stear, M. J., Henderson, N. G., Kerr, A., McKellar, Q. A., Mitchell, S., Seeley, C. and Bishop, S. C. ( 2002). Eosinophilia as a marker of resistance to Teladorsagia circumcincta in Scottish Blackface lambs Parasitology 124, 553560.
Stear, M. J., Hetzel, D. J. S., Brown, S. C., Gershwin, L. J., Mackinnon, M. J. and Nicholas, F. W. ( 1990). The relationships among ecto- and endoparasite levels, class I antigens of the bovine major histocompatibility system, immunoglobulin E levels and weight gain. Veterinary Parasitology 34, 303321.
Stear, M. J., Innocent, G. T. and Buitkamp, J. ( 2005). The evolution and maintenance of polymorphism in the major histocompatibility complex. Veterinary Immunology and Immunopathology 108, 5357.
Stear, M. J., Mitchell, S., Strain, S. A. J., Bishop, S. C. and McKellar, Q. A. ( 2000 b). The influence of age on the variation among sheep in susceptibility to natural nematode infection. Veterinary Parasitology 89, 3136.
Stear, M. J., Park, M. and Bishop, S. C. ( 1996). The key components of resistance to Ostertagia circumcincta in lambs. Parasitology Today 12, 438441.
Stear, M. J., Strain, S. A. J. and Bishop, S. C. ( 1999). Mechanisms underlying resistance to nematode infection. International Journal for Parasitology 29, 5156.
Stewart, M. A., Miller, R. F. and Douglas, J. R. ( 1937). Resistance of sheep of different breeds to infestation by Ostertagia circumcincta. Journal of Agricultural Research 55, 923930.
Strain, S. A. J., Bishop, S. C., Henderson, N. G., Kerr, A., McKellar, Q. A., Mitchell, S. and Stear, M. J. ( 2002). The genetic control of IgA activity against Teladorsagia circumcincta and its association with parasite resistance in naturally infected sheep. Parasitology 124, 545552.
Strain, S. A. J. and Stear, M. J. ( 2001). The influence of protein supplementation on the immune response to Haemonchus contortus. Parasite Immunology 23, 523531.
Stromberg, B. E. ( 1997). Environmental factors influencing transmission. Veterinary Parasitology 72, 247264.
Stromberg, B. E. and Averbeck, G. A. ( 1999). The role of parasitic epidemiology in the management of grazing cattle. International Journal for Parasitology 29, 3339.
Sutherland, I. A., Moen, I. C. and Leathwick, D. M. ( 2002). Increased burdens of drug-resistant nematodes due to anthelmintic treatment. Parasitology 125, 375381.
Sykes, A. R. and Coop, R. L. ( 2001). Interaction between nutrition and gastrointestinal parasitism in sheep. New Zealand Veterinary Journal 49, 222226.
Urquhart, G. M., Armour, J., Duncan, J. L., Dunn, A. M. and Jennings, F. W. ( 1987). Veterinary Parasitology. Longman Scientific and Technical, Avon, UK.
van Houtert, M. F. J., Barger, I. A., Steel, J. W., Windon, R. G. and Emery, D. L. ( 1995). Effects of dietary protein intake on responses of young sheep to infection with Trichostrongylus colubriformis. Veterinary Parasitology 56, 163180.
Vercruysse, J., Knox, D. P., Schetters, T. P. M. and Willadsen, P. ( 2004). Veterinary parasitic vaccines: pitfalls and future directions. Trends in Parasitology 20, 488492.
Vlassoff, A., Leathwick, D. M. and Heath, A. C. G. ( 2001). The epidemiology of nematode infections of sheep. New Zealand Veterinary Journal 49, 213221.
Waghorn, T. S., Leathwick, D. M., Chen, L.-Y., Gray, R. A. J. and Skipp, R. A. ( 2002). Influence of nematophagous fungi, earthworms and dung burial on development of the free-living stages of Ostertagia (Teladorsagia) circumcincta in New Zealand. Veterinary Parasitology 104, 119129.
Wallace, D. S., Bairden, K., Duncan, J. L., Eckersall, P. D., Fishwick, G., Gill, M., Holmes, P. H., McKellar, Q. A., Murray, M., Parkins, J. J. and Stear, M. J. ( 1998). The influence of dietary supplementation with urea on resilience and resistance to infection with Haemonchus contortus. Parasitology 116, 6772.
Wallace, D. S., Bairden, K., Duncan, J. L., Eckersall, P. D., Fishwick, G., Holmes, P. H., McKellar, Q. A., Mitchell, S., Murray, M., Parkins, J. J. and Stear, M. J. ( 1999). The influence of increased feeding on the susceptibility of sheep to infection with Haemonchus contortus. Animal Science 69, 457463.
Wallace, D. S., Bairden, K., Duncan, J. L., Fishwick, G., Gill, M., Holmes, P. H., McKellar, Q. A., Murray, M., Parkins, J. J. and Stear, M. J. ( 1995). Influence of supplementation with dietary soyabean meal on resistance to haemonchosis in Hampshire down lambs. Research in Veterinary Science 58, 232237.
Wallace, D. S., Bairden, K., Duncan, J. L., Fishwick, G., Holmes, P. H., McKellar, Q. A., Murray, M., Parkins, J. J. and Stear, M. J. ( 1996). Influence of soyabean meal supplementation on the resistance of Scottish Blackface lambs to haemonchosis. Research in Veterinary Science 60, 138143.
Waller, P. J., Bernes, G., Rudby-Martin, L., Ljungstrõm, B. and Rydzik, A. ( 2004 a). Evaluation of copper supplementation to control Haemonchus contortus infections of sheep in Sweden. Acta Veterinaria Scandinavica 45, 149160.
Waller, P. J. and Faedo, M. ( 1996). The prospects for biological control of the free-living stages of nematode parasites of livestock. International Journal for Parasitology 26, 915925.
Waller, P. J., Schwan, O., Ljungström, B.-L., Rydzik, A. and Yeates, G. W. ( 2004 b). Evaluation of biological control of sheep parasites using Duddingtonia flagrans under commercial farming conditions on the island of Gotland, Sweden. Veterinary Parasitology 126, 299315.
Waller, P. J. and Thamsborg, S. M. ( 2005). Nematode control in ‘green’ ruminant production systems. Trends in Parasitology 20, 493497.
Wiener, G. ( 1979). Review of genetic aspects of mineral metabolism with particular reference to copper in sheep. Livestock Production Science 6, 223232.
Williams, B. and Warren, J. ( 2004). Effects of spatial distribution on the decomposition of sheep faeces in different vegetation types. Agriculture, Ecosystems and Environment 103, 237243.
Yatsuda, A. P., Krijgsveld, J., Cornelissen, A. W. C. A., Heck, A. J. R. and de Vries, E. ( 2005). Comprehensive analysis of the secreted proteins of the parasite Haemonchus contortus reveals extensive sequence variation and differential immune recognition. Journal of Biological Chemistry 278, 1694116951.
Yazwinski, T. A., Goode, L., Moncol, D. J., Morgan, G. W. and Linnerud, A. C. ( 1979). Parasite resistance in straightbred and crossbred Barbados Blackbelly sheep. Journal of Animal Science 49, 919926.
Yazwinski, T. A., Goode, L., Moncol, D. J., Morgan, G. W. and Linnerud, A. C. ( 1981). Haemonchus contortus resistance in straightbred and crossbred Barbados Blackbelly sheep. Journal of Animal Science 51, 279284.
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Parasitology
  • ISSN: 0031-1820
  • EISSN: 1469-8161
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