The first co-ordinated approach to controlling bovine mastitis in the UK began in the 1960’s with the development of the Five Point Plan from research conducted at the National Institute for Research in Dairying (NIRD) at Reading. As the name suggests the Plan was comprised of five key points, namely the identification and treatment of clinical cases, routine antibiotic dry cow therapy for every cow at drying-off, post-milking teat disinfection, culling of persistently infected cows and regular maintenance of the milking machine.
Uptake of the plan resulted in rapid progress in control of clinical and sub-clinical mastitis as illustrated in Figure 1. This came about primarily through better control of contagious mastitis pathogens (i.e. those adapted for survival within the host mammary gland). The incidence rate of clinical mastitis fell from more than 150 cases per 100 cows per year to just 40 cases per 100 cows per year between 1967 and 1982. At the same time, the national bulk milk somatic cell count reduced from over 600,000 cells/ml to 400,000 cells/ml. The introduction of EC Milk Hygiene Directive (92/46) in 1991, imposing an upper limit of 400,000 cells/ml in bulk milk for human consumption coupled with incentives offered to dairy farmers to produce milk of higher quality with a low somatic cell count further reduced the prevalence of infected cows in the UK.
From the early 1980s until recently the incidence rate of clinical mastitis in the UK has been difficult to determine. Several small scale studies between 1998 and 2002 estimated the mean figure at approximately 35 to 50 cases per 100 cows per year (not dissimilar to that seen 15-20 years earlier). These studies identified Escherichia coli and Streptococcus uberis as the commonest cause of clinical mastitis, with contagious pathogens being significantly less important. These studies demonstrated what was being appreciated anecdotally – that environmental pathogens were becoming more important in the aetiology of mastitis in the UK.
This increased perception of the importance of the environment in mastitis control led, in the late 1990s, to the Department for the Environment, Food and Rural Affairs (DEFRA) introduced the ‘Six Point Plan’ for mastitis control, with the sixth point being management of the cow’s environment.
|Last Updated on Thursday, 06 March 2014 16:00|