Dry dairy cows, in-calf heifers at risk from summer mastitis
Early July to September is the peak period for summer mastitis, which is more widespread in autumn calving herds.
Dry dairy cows and in-calf heifers are most at risk.
The bacteria causing the disease are carried and spread by flies. The first line of defence is to minimise the exposure of animals to flies.
If possible, vulnerable animals should not have access to low-lying, sheltered, wooded, damp areas, where flies are most abundant.
All animals on the farm should be treated regularly with a pour-on fly repellent. This will not only help prevent summer mastitis, but will also be of great benefit to dairy cows — and to the people who milk them. There is little point in treating only some of the animals on the farm against flies.
Another well proven means of prevention is the application of Stockholm tar to the udders and flanks of susceptible animals. The tar has to be applied regularly. This may be time consuming, especially if animals are well away from yards, but is well worth while on farms that have regular problems from the disease.
As well as taking preventative measures, vulnerable animals should be closely inspected at least once daily.
Symptoms are fairly straightforward to detect. Infected quarters get swollen, with stiffness in the near leg. Infected animals show clear signs of sickness; they usually separate from the group and have raised temperatures.
Unless detected at the very beginning, which is difficult, the affected quarter will be lost. If neglected, the animal becomes poisoned and may abort or die. Therefore very prompt veterinary treatment is essential if severe losses are to be avoided.
