Summer mastitis warning issued after spike in cases

A surge in summer mastitis has led to experts advising beef farmers to be vigilant when checking cattle.

Laboratory-confirmed mastitis cases are at a three-year high (see table), which has been attributed to the summer of 2019 being exceptional for grass growth and flies.

Figures from the Animal and Plant Health Agency (APHA) show 157 laboratory-confirmed cases, with E coli and Strep uberis being the most common strains.

See also: Fly control in cattle: the options compared

Cases of mastitis confirmed by APHA and SRUC (Scotland’s Rural College) Laboratories


Number of overall mastitis cases (May/June/July)













What to do

Dr Basic Lowman, Senior beef consultant at SAC (Scottish Agricultural College) Consulting, recommends the following:

  • Observe: look for animals away from the main group and hungry calves
  • Check: swollen teats and udders
  • Graze: stock susceptible animals in exposed fields away from trees and open water – which is where flies breed.

Dr Lowman said that once a case of summer mastitis occurs, the level of infection carried by flies increases dramatically as they land on an infected area and then fly off to a neighbouring cow. 

“The best way to avoid this is to bring all infected cows indoors, which will be necessary in any case if they are to be treated,” he added.

Five prevention methods for summer mastitis

  1. Teat sealants: these are squeezed into the teat canal – similar to tubes of antibiotics, but longer-lasting and cheaper.  It is essential the end of the teat is carefully cleaned and disinfected before the tube is inserted. They are supplied by vets who will explain how to use them.
  2. Stockholm tar: an old-fashioned remedy with the tar forming a physical barrier over the end of the teat. However, it is difficult to apply and to be effective, needs replacing weekly.  An alternative is to use polyurethane varnish as a teat dip
  3. Spray: use one of a number of products on the market aimed at deterring or killing flies
  4. Insecticide ear tags: for best effect, they need to be applied in early spring to kill as many flies as possible while numbers are relatively low
  5. Garlic: naturally occurring sulphur compounds in the ingredient seep out through pores and sweat glands, acting as a repellent to flies and other biting insects

Source: Basil Lowman, SAC Consulting

Grass growth

UK grass growth data for late June and July showed some weeks averaged up to 74kgDM/ha.

This was more than 40kgDM/ha above last year’s drought-hit growth and 21kg above that of 2017.