This specially curated collection features four reviews of current and key research on mastitis in dairy cattle.

The first chapter reviews the indicators of mastitis and the contagious and environmental pathogens which cause it. It then discusses how mastitis can be managed and controlled on dairy farms, including consideration of dry cow therapy and the use of antibiotics.

The second chapter examines the impact of clinical and subclinical mastitis in cows on milk quality, and provides a detailed account of indicators of mastitis. It describes the impact of mastitis on milk composition and quality, addressing its effect on the protein, fat, lactose and iron content of milk.

The third chapter reviews advances in dairy cattle breeding to improve resistance to mastitis. It includes sections on both conventional and new phenotypes for improving resistance to clinical mastitis and concludes with a section on increasing rates of genetic gain through genomic selection.

The final chapter considers recent research on the prevalence and development of antimicrobial resistance in mastitis pathogens. It shows how consistent diagnostic protocols and recording systems, attention to medical history, appropriate choice of antibiotics and control of treatment duration can all contribute to minimizing unnecessary use of antimicrobials and promoting effective treatment of mastitis.

Chapter 1 - Aetiology, diagnosis and control of mastitis in dairy herds: P. Moroni, Cornell University, USA and Universit à degli Studi di Milano, Italy; F. Welcome, Cornell University, USA; and M.F. Addis, Porto Conte Ricerche, Italy; 1 Introduction 2 Indicators of mastitis: somatic cell count 3 Indicators of mastitis: non-cell inflammation markers 4 Contagious pathogens causing mastitis 5 Environmental pathogens: Escherichia coli, Klebsiella and environmental streptococci 6 Other pathogens: Prototheca, coagulase-negative staphylococci and other microorganisms 7 Management and control of mastitis 8 Dry cow therapy 9 The use of antibiotics 10 Where to look for further information 11 References
Chapter 2 - Mastitis, milk quality and yield: P. Moroni, Cornell University, USA and University of Milano, Italy; F. Welcome, Cornell University, USA; and M. F. Addis, Porto Conte Ricerche, Italy; 1 Introduction 2 Indicators of mastitis 3 Impact of mastitis on milk composition 4 Impact of mastitis on dairy product quality 5 Impact of mastitis on milk production yield 6 Conclusion and future trends 7 References
Chapter 3 - Advances in dairy cattle breeding to improve resistance to mastitis: John Cole, USDA-ARS, USA; 1 Introduction 2 Conventional phenotypes for improving resistance to clinical mastitis 3 New phenotypes for improving resistance to clinical mastitis 4 National and international genetic improvement programmes for resistance to clinical mastitis 5 Increasing rates of genetic gain through genomic selection 6 Conclusion 7 Future trends in research 8 Acknowledgements 9 Where to look for further information 10 References
Chapter 4 - Minimising the development of antimicrobial resistance on dairy farms: appropriate use of antibiotics for the treatment of mastitis: Pamela L. Ruegg, University of Wisconsin-Madison, USA; 1 Introduction 2 Use of antimicrobials on dairy farms 3 Clinical relevance of antimicrobial resistance data 4 Trends in the antimicrobial resistance of mastitis pathogens 5 Ensuring effective use of antibiotics in the treatment of mastitis: diagnosis, antibiotic choice and duration of treatment 6 Ensuring effective use of antibiotics in the treatment of mastitis: targeting treatment 7 Conclusions 8 Where to look for further information 9 References