No CrossRef data available.
Article contents
Sheep health: research developments and emerging problems
Published online by Cambridge University Press: 02 September 2010
Abstract
Relative to other livestock sectors sheep production has a high wastage through mortality, suboptimal husbandry practices and premature culling. A significant but unquantified component of this loss is attributable to infectious and parasitic disease. Some common infectious diseases (e.g. those caused by Clostridia) are amenable to effective control but regular sporadic outbreaks indicate that, from time to time, control measures fail or are improperly applied. Other diseases, notably those causing abortion, continue to present problems, particularly chlamydial abortion and toxoplasmosis. Inability to diagnose infection before the onset of clinical signs hinders the control of scrapie and pulmonary adenomatosis (jaagsiekte) and the only vaccine against orf is of limited efficacy.
However, the new information being generated by application of molecular biological techniques in some of these problem areas carries promise of improved control. Good examples are provided by research which has led to a blood test for discriminating between sheep that are genetically susceptible or resistant to scrapie and by studies on Chlamydia psittaci which have identified essential protective antigens and which thereby improve prospects for significant vaccine enhancement.
The world-wide importance of gastrointestinal parasitism and the emergence of anthelmintic resistance have spurred efforts, internationally, to develop an alternative biological control system. Evidence that protective vaccination may be feasible is accruing but the time scale to a real product may be long.
Factors to be considered in assessing future disease trends include the impact of a ‘frontier-free’ Europe, changes in husbandry practices, introduction of new livestock species, altered land use and climatic change resulting from global warming. Some predictions are made.
- Type
- Research Article
- Information
- BSAP Occasional Publication , Volume 14: New Developments in Sheep Production , January 1990 , pp. 83 - 92
- Copyright
- Copyright © British Society of Animal Production 1990
References
REFERENCES
Aitken, I. D. 1986. Chlamydial diseases of ruminants. EUR 10056 EN. Commission of the European Communities, Luxembourg.Google Scholar
Aitken, I. D., Anderson, I. E. and Robinson, G. W. 1986. Ovine chlamydial abortion: limitations of inactivated vaccine. In Chlamydial Diseases of Ruminants (ed. Aitken, I. D.), EUR 10056 EN, pp. 55–65. Commission of the European Communities, Luxembourg.Google Scholar
Allan, I., Cunningham, T. M. and Lovett, M. A. 1984. Molecular cloning of the major outer membrane protein of Chlamydia trachomatis. Infection and Immunity 45: 637–641.CrossRefGoogle ScholarPubMed
Anderson, I. E., Tan, T. W., Jones, G. E. and Herring, A. J. 1990. Efficacy against ovine enzootic abortion of an experimental vaccine containing purified elementary bodies of Chlamydia psittaci. Veterinary Microbiology In press.CrossRefGoogle ScholarPubMed
Angus, K. W. and Blewett, D. A. ed. 1989. Cryptosporidiosis: Proceedings of the First International Workshop, Edinburgh.Google Scholar
Angus, K. W. and Hodgson, J. C. 1990. Nephrosis in lambs: recognition and management. In Practice In press.CrossRefGoogle Scholar
Angus, K. W., Hodgson, J. C., Hosie, B. D., Low, J. C., Mitchell, G. B. B., Dyson, D. A. and Holiman, A. 1989. Acute nephropathy in young lambs. Veterinary Record 124: 9–14.CrossRefGoogle ScholarPubMed
Benson, J. A. and Williams, B. M. 1974. Acute renal failure in lambs. British Veterinary Journal 130: 475–481.CrossRefGoogle ScholarPubMed
Cheeseman, C. L., Wilesmith, J. W. and Stuart, F. A. 1989. Tuberculosis: the disease and its epidemiology in the badger, a review. Epidemiology and Infection 103: 113–125.Google ScholarPubMed
Clarke, I. N., Ward, M. E. and Pickett, M. A. 1988. The molecular biology of chlamydial outer envelope proteins.Proceedings of the European Society for Chlamydia Research, Esculapio,Bologna, pp. 76–79.Google Scholar
Clements, J. D. 1987. Use of attenuated mutants of Salmonella as carriers for delivery of heterologous antigens to the secretory immune system. Pathology and Immunology Research 6: 137–146.CrossRefGoogle Scholar
Davies, D. C. and Kimberlin, R. H. 1985. Selection of Swaledale sheep of reduced susceptibility to experimental scrapie. Veterinary Record 116: 211–214.CrossRefGoogle ScholarPubMed
De Villiers, E. M., Els, H. J. and Verwoerd, D. W. 1975. Characteristics of an ovine herpesvirus associated with pulmonary adenomatosis (jaagsiekte) in sheep. South African Journal of Medical Science 40: 165–175.Google ScholarPubMed
De Villiers, E. M. and Verwoerd, D. W. 1980. Presence of Herpesvirus ovis DNA sequences in cellular DNA from sheep lungs affected with jaagsiekte (pulmonary adenomatosis). Onderstepoort Journal of Veterinary Research 47: 109–112.Google ScholarPubMed
Dickinson, A. G., Stamp, J. J., Renwick, C. C. and Rennie, J. C. 1968. Some factors controlling the incidence of scrapie in Cheviot sheep infected with a Cheviot-passaged scrapie agent. Journal of Comparative Pathology 78: 33–32.CrossRefGoogle ScholarPubMed
Fodor, L., Varga, J., Hajtos, J., Donachie, W. and Gilmour, N. J. L. 1988. Characterisation of a new serotype of Pasteurella haemolytica isolated in Hungary. Research in Veterinary Science 44: 399.CrossRefGoogle ScholarPubMed
Foster, J. D. and Dickinson, A. G. 1988a. Genetic control of scrapie in Cheviot and Suffolk sheep. Veterinary Record 123: 159.CrossRefGoogle ScholarPubMed
Foster, J. D. and Dickinson, A. G. 1988b. The unusual properties of CH1641, a sheep-passaged isolate of scrapie. Veterinary Record 123: 5–8.CrossRefGoogle ScholarPubMed
Fraser, H., McBride, P. A., Scott, J. R., Hunter, N. and Foster, J. D. 1989. Scrapie, models and homologues. State Veterinary Journal 43: 11–22.Google Scholar
Fukushi, H. and Hirai, K. 1989. Genetic diversity of avian and mammalian Chlamydia psittaci strains and relation to host origin. Journal of Bacteriology 171: 2850–2855.CrossRefGoogle ScholarPubMed
Gibson, P. H., Somerville, R. A., Fraser, H., Foster, J. D. and Kimberlin, R. H. 1987. Scrapie associated fibrils in the diagnosis of scrapie in sheep. Veterinary Record 120: 125–127.CrossRefGoogle ScholarPubMed
Greig, A., Linklater, K. A. and Clark, W. A. 1984. Persistent orf in a ram. Veterinary Record 115: 149.CrossRefGoogle ScholarPubMed
Herring, A. J., Sharp, J. M., Scott, F. M. M. and Angus, K. W. 1983. Further evidence for a retrovirus as the aetiological agent of sheep pulmonary adenomatosis (jaagsiekte). Veterinary Microbiology 8: 237–249.CrossRefGoogle ScholarPubMed
Herring, A. J., TAn, T. W., Baxter, S., Inglis, N. F. and Dunbar, S. 1989. Sequence analysis of the major outer membrane protein of an ovine abortion strain of Chlamydia psittaci. Federation of European Microbiological Societies Microbiological Letters 65: 153–158.CrossRefGoogle Scholar
Hodgson, J. C., King, T. J., Hay, L. A. and Elston, D. A. 1989. Biochemical and haematological evidence of endotoxic shock in gnotobiotic lambs with watery mouth disease. Research in Veterinary Science 47: 119–124.CrossRefGoogle ScholarPubMed
Hope, J., Morton, L. J. D., Farquhar, C. F., Multhaup, A., Beyreuther, K. and Kimberlin, R. H. 1986. The major polypeptide of scrapie-associated fibrils (SAF) has the same size, change distribution and N-terminal protein (PrP). European Molecular Biology Organisation Journal 5: 2591–2597.CrossRefGoogle Scholar
Howe, K. S. 1976. The cost of mortality in sheep production in the UK 1971–74. Report, University of Exeter, Agricultural Economics Unit, No. 198.Google Scholar
Hunter, N., Foster, J. D., Dickinson, A. G. and Hope, J. 1989. Linkage of the gene for the scrapie-associated fibril protein (PrP) to the Sip gene in Cheviot sheep. Veterinary Record 12A: 364–366.CrossRefGoogle Scholar
Hunter, N., Hope, J., McConnell, I. and Dickinson, A. G. 1987. Linkage of the scrapie-associated fibril protein (PrP) gene and Sine using congenic mice and restriction fragment length polymorphism analysis. Journal of General Virology 68: 2711–2716.CrossRefGoogle Scholar
Jenkinson, D. M., McEwan, P. E., Onwuka, S. K., Moss, V. A., Elder, H. Y., Hutchison, G. and Reid, H. W. 1990. The polymorphonuclear and mast cell responses in ovine skin infected with orf virus. Veterinary Dermatology 1: In press.CrossRefGoogle ScholarPubMed
Jones, J. E. T. 1985. An investigation of mastitis in sheep: preliminary phase. Proceedings of the Sheep Veterinary Society 10: 48–51.Google Scholar
Jones, J. E. T. 1990. Mastitis in ewes. In Diseases of Sheep. 2nd ed. (ed. Martin, W. B. and Aitken, I. D.). Blackwells, Oxford. In press.Google Scholar
Kirkham, J., Robinson, C. and Spence, J. A. 1989. Site-specific variations in the composition of healthy sheep peridontia. Archives of Oral Biology 34: 405–411.CrossRefGoogle Scholar
Lloyd, S. 1981. Progress in immunization against parasitic helminths. Parasitology 83: 225–242.CrossRefGoogle ScholarPubMed
McClenaghan, M., Herring, A. J. and Aitken, I. D. 1984. Comparison of Chlamydia psittaci isolates by DNA restriction endonuclease analysis. Infection and Immunity 45: 384–389.CrossRefGoogle ScholarPubMed
McKeever, D. J., Jenkinson, D. M., Hutchison, G. and Reid, H. W. 1988. Studies of the pathogenesis of orf virus infection in sheep. Journal of Comparative Pathology 99: 317–328.CrossRefGoogle ScholarPubMed
McKeever, D. J. and Reid, H. W. 1986. Survival of orf virus under British winter conditions. Veterinary Record 118: 613–614.CrossRefGoogle ScholarPubMed
Mellor, P. S., Boorman, J. P. T., Wilkinson, P. J. and Martinez-Gomez, F. 1983. Potential vectors of bluetongue and African horse sickness viruses in Spain. Veterinary Record 112: 229–230.Google Scholar
Mercer, A. A., Fraser, K., Barns, G. and Robinson, A. J. 1987. The structure and cloning of orf virus DNA. Virology 157: 1–12.CrossRefGoogle ScholarPubMed
Miller, H. R. P. 1987. Gastrointestinal mucus, a medium for survival and for elimination of gastrointestinal nematodes and protozoa. Parasitology 94: 77–100.CrossRefGoogle ScholarPubMed
Munn, E. A. 1977. A helical polymeric extracellular protein associated with the luminal surface of Haemonchus contortus. Tissue and Cell 9: 23–24.CrossRefGoogle ScholarPubMed
Munn, E. A., Greenwood, C. A. and Goadwell, W. J. 1987. Vaccination of young lambs by means of a protein fraction extracted from adult Haemonchus contortus. Parasitology 95: 385–398.CrossRefGoogle Scholar
Nussbaum, R. E., Henderson, W. M., Pattison, I. H., Elcock, N. V. and Davies, D. C. 1975. The establishment of sheep flocks of predictable susceptibility to experimental scrapie. Research in Veterinary Science 18: 49–58.CrossRefGoogle Scholar
Opdebeeck, J. P., Wong, J. M., Jackson, L. A. and Dobson, C. 1988. Vaccines to protect Hereford cattle against the cattle tick Boophilus microplus. Immunology 63: 363–367.Google ScholarPubMed
Parry, M. L., Carter, J. R. and Porter, J. H. 1989. The greenhouse effect and the future of UK agriculture. Journal of the Royal Agricultural Society of England 150: 120–131.Google Scholar
Pattison, I. H. 1988. Fifty years with scrapie: a personal reminiscence. Veterinary Record 123: 661–666.Google ScholarPubMed
Perez-Artinez, J. A. and Storz, J. 1985. Antigenic diversity of Chlamydia psittaci of mammalian origin determined by microimmunofluorescence. Infection and Immunity 50: 905–910.CrossRefGoogle Scholar
Robinson, A. J., Barns, G., Fraser, K., Carpenter, E. and Mercer, A. A. 1987. Conservation and variation in orf virus genomes. Virology 157: 13–23.CrossRefGoogle ScholarPubMed
Robinson, A. J. and Mercer, A. A. 1988. Orf virus and vaccinia virus do not cross-protect sheep. Archives of Virology 101: 255–259.CrossRefGoogle Scholar
Scott, A. C., Dove, S. H., Venables, C. and Dawson, M. 1987. Detection of scrapie-associated fibrils as an aid to the diagnosis of natural sheep scrapie. Veterinary Record 120: 280–281.CrossRefGoogle Scholar
Scott, F. M. M. 1984. Studies on sheep herpesvirus and its rôle in jaagsiekte (sheep pulmonary adenomatosis). Ph.D. Thesis, Council for National Academic Awards.Google Scholar
Scott, F. M. M., Sharp, J. M., Angus, K. W. and Gray, E. W. 1984. Infection of specific pathogenfree lambs with a herpesvirus isolated from pulmonary adenomatosis. Archives of Virology 80: 147–162.CrossRefGoogle Scholar
Sharp, J. M. 1987. Sheep pulmonary adenomatosis: a contagious tumour and its cause. Cancer Surveys 6: 73–82.Google ScholarPubMed
Sharp, J. M., Angus, K. W., Gray, E. W. and Scott, F. M. M. 1983. Rapid transmission of sheep pulmonary adenomatosis (jaagsiekte) in young lambs. Archives of Virology 78: 89–95.CrossRefGoogle ScholarPubMed
Sharp, J. M., Herring, A. J., Angus, K. W., Scott, F. M. M. and Jassim, F. A. 1985. Isolation and in vitro propagation of a retrovirus from sheep pulmonary adenomatosis. In Slow Virus Diseases in Sheep, Goats and Cattle (ed. Sharp, J. M. and Hoff-Jorgensen, R.), EUR 8076 EN, pp. 345–348. Commission of the European Communities, Luxembourg.Google Scholar
Sheep Research Consultative Committee. 1987. Report to the Priorities Board. Ministry of Agriculture, Fisheries and Food/Department of Agriculture for Scotland/Agricultural and Food Research Council.Google Scholar
Shore, R. C., Moxham, B. J. and Benkovitz, B. K. B. 1989. Effects of inflammatory periodontal disease (“broken mouth”) on the ultrastructure of collagen fibrils in the sheep incisor periodontium. Research in Veterinary Science 47: 148–151.CrossRefGoogle ScholarPubMed
Smith, W. D., Jackson, F., Graham, R., Jackson, E. and Williams, J. 1987. Mucosal IgA production and lymph cell traffic following prolonged low level infection of Ostertagia circumcincta in sheep. Research in Veterinary Science 43: 320–326.CrossRefGoogle ScholarPubMed
Smith, W. D., Jackson, F., Jackson, E., Graham, R., Williams, J., Willasden, W. M. and Fehilly, B. 1986. Transfer of immunity to Ostertagia circumcincta IgA memory between identical sheep by lymphocytes collected from gastric lymph. Research in Veterinary Science 41: 300–306.CrossRefGoogle ScholarPubMed
Spears, P. and Storz, J. 1979. Biotyping of Chlamydia psittaci based on inclusion morphology and response to diethylaminoethyl-dextran and cycloheximide. Infection and Immunity 24: 224–232.CrossRefGoogle ScholarPubMed
Stephens, R. S., Mullenbach, G., Sanchez-Pescador, R. and Agabian, N. 1986. Sequence analysis of the major outer membrane protein gene from Chlamydia trachomatis Serovar L2. Journal of Bacteriology 168: 1277–1282.CrossRefGoogle ScholarPubMed
Tan, T. W., Herring, A. J., McClenaghan, M., Huang, H.-S., Anderson, I. E., Inglis, N. F., Jones, G. E. and Buxton, D. 1988. Immunoblotting analysis of the humoral immune response in sheep infected with ovine abortion strain of Chlamydia psittaci.Proceedings of the European Society for Chlamydia Research, Esculapio,Bologna, p. 136.Google Scholar
Taylor, M. A. and Hunter, K. R. 1989. Anthelmintic drug resistance in the UK. Veterinary Record 125: 143–147.CrossRefGoogle ScholarPubMed
Timms, P., Eaves, F. M., Girjes, A. A. and Lavin, M. F. 1988. Comparison of Chlamydia psittaci isolates by restriction endonuclease and DNA probe analyses. Infection and Immunity 56: 287–290.CrossRefGoogle ScholarPubMed
Verwoerd, D. W., Williamson, A. L. and De Villiers, E. M. 1980. Aetiology of jaagsiekte: transmission by means of subcellular fractions and evidence for the involvement of a retrovirus. Onderstepoort Journal of Veterinary Research 47: 275–280.Google ScholarPubMed
Waldham, D. G., Delong, W. J. and Hall, R. F. 1982. Efficacy of a bacterin prepared from Chlamydia psittaci grown in cell culture for experimental immunisation of ewes. Veterinary Microbiology 7: 493–498.CrossRefGoogle Scholar
Willadsen, P., McKenna, R. V. and Riding, G. A. 1988. Isolation from the cattle tick, Boophilus microplus, of antigenic material capable of eliciting a protective immunological response in the bovine host. International Journal for Parasitology 18: 83–89.CrossRefGoogle ScholarPubMed