ABSTRACT

Aetiology, diagnosis and control of mastitis in dairy herds P. Moroni, Cornell University, USA and Università 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

Mastitis is one of the most economically important diseases in dairy production. Intramammary infections (IMI) continue to be the most important cause of mastitis in dairy cattle, accounting for 38% of the total costs of the common production diseases (Kossaibati and Esslemont, 1997). In the last decade, several groups have estimated the losses associated with clinical mastitis (CM), and the average costs per case (US$) of Gram-positive, Gram-negative and other microorganisms were $133.73, $211.03 and $95.31, respectively (Cha et al., 2013; Gröhn et al., 2004). These costs include treatment, culling, death and decreased milk production. In addition to reduced cow welfare and increased veterinary costs, episodes of mastitis are associated with reduction of milk production (Bar et al., 2007; Schukken et al., 2009), decreased fertility (Hertl et al., 2010; Santos et al., 2004), and increased culling and death risk (Hertl et al., 2011).