Volume 160, Issue 8 p. 253-258
Paper & Article

Survey of the incidence and aetiology of mastitis on dairy farms in England and Wales

A. J. Bradley MA, VetMB, PhD, DCHP, DipECBHM, MRCVS

Corresponding Author

A. J. Bradley MA, VetMB, PhD, DCHP, DipECBHM, MRCVS

School of Clinical Veterinary Science, University of Bristol, Langford, Bristol, BS40 5DU

Dr Bradley is also at Quality Milk Management Services, Unit 1, Lodge Hill Industrial Park, Station Road, Westbury-sub-Mendip BA5 1EYSearch for more papers by this author
K. A. Leach BSc, MSc, PhD

K. A. Leach BSc, MSc, PhD

School of Clinical Veterinary Science, University of Bristol, Langford, Bristol, BS40 5DU

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J. E. Breen BVSc, CertCHP, MRCVS

J. E. Breen BVSc, CertCHP, MRCVS

School of Clinical Veterinary Science, University of Bristol, Langford, Bristol, BS40 5DU

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L. E. Green BVSc, MSc, PhD, MRCVS

L. E. Green BVSc, MSc, PhD, MRCVS

Ecology and Epidemiology Group, Department of Biological Sciences, University of Warwick, Coventry, CV4 7AL

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M. J. Green BVSc, PhD, DCHP, DipECBHM, MRCVS

M. J. Green BVSc, PhD, DCHP, DipECBHM, MRCVS

School of Veterinary Medicine and Science, and School of Mathematical Sciences, University of Nottingham, Sutton Bonington Campus, Sutton Bonington, LE12 5RD

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First published: 24 February 2007
Citations: 258

Abstract

A survey of clinical and subclinical mastitis was carried out on 97 dairy farms in England and Wales, selected at random from members of a national milk recording scheme. The farmers were asked to collect aseptic milk samples from five consecutive cases of clinical mastitis and from five quarters with high somatic cell counts using a defined protocol, and they completed a questionnaire that included information on the cows sampled, the herd and the history of mastitis in the herd. The samples were collected throughout the year. The mean incidence of clinical mastitis was 47 cases per 100 cows per year (estimated from historic farm records) and 71 cases per 100 cows per year (estimated from the samples collected). Streptococcus uberis and Escherichia coli were isolated in pure culture from 23·5 per cent and 19·8 per cent, respectively, of the clinical samples; 26·5 per cent of the clinical samples produced no growth. The most common isolates from the samples with high cell counts were coagulase-negative staphylococci (15 per cent), S uberis (14 per cent) and Corynebacterium species (10 per cent). Staphylococcus aureus and coagulase-positive staphylococci together accounted for 10 per cent of the samples with high somatic cell counts; 39 per cent produced no bacterial growth.