Summer Mastitis in Cattle: Welfare and Prevention

Summer mastitis is a severe fly-transmitted infection affecting dry cows and heifers. This guide covers welfare and prevention.

Key Facts

Summer mastitis is caused by a complex of bacteria transmitted by head flies (Hydrotaea irritans)
It predominantly affects dry cows and maiden heifers during summer months
Affected animals develop severe painful swelling of the quarter with thick creamy discharge
Systemic illness including fever and toxaemia causes significant welfare distress
Without treatment, affected quarters are permanently lost and animals may die
Prevention through fly control and teat sealants is highly effective

Welfare Considerations and Management

Welfare-centred management requires early recognition and aggressive treatment. Stripping the affected quarter removes toxin-laden secretions. High-dose antibiotics (penicillin and streptomycin) treat the infection. Anti-inflammatories reduce pain and systemic illness. Despite treatment, permanent quarter loss is common. Prevention through permethrin-based fly control (Stockholm tar, fly repellent ear tags) applied to susceptible animals from June dramatically reduces incidence. Internal teat sealants protect dry cows.

What You Can Do

Apply fly repellent (Stockholm tar, permethrin) to dry cows and heifers from June onwards
Use internal teat sealants in dry cows to prevent bacterial entry
Inspect susceptible animals daily during summer for signs of udder swelling
Seek veterinary treatment immediately if summer mastitis is suspected