Summer Mastitis Welfare in Dry Cows and Heifers

Summer mastitis causes severe systemic illness and permanent teat canal damage in dry cows and heifers. Prevention through fly control and teat sealants prevents most cases.

Key Facts

Summer mastitis is caused by Trueperella pyogenes and associated bacteria transmitted by flies
It primarily affects dry cows and maiden heifers in late summer
Affected quarters develop thick foul-smelling secretion and become permanently damaged
Systemically ill cows with fever, toxaemia, and depression require prompt antibiotic treatment
Preventing fly access through insect repellents and teat sealants at drying off prevents most cases

Welfare Considerations

Summer mastitis causes severe welfare compromise through acute systemic toxaemia with fever, anorexia, and depression alongside the severe local infection of the affected quarter. Cows and heifers affected show signs of significant pain. Untreated or late-treated cases suffer permanent loss of the affected quarter and may require culling. Prevention is highly effective: applying long-acting teat sealants at drying off and using insect repellents on susceptible animals during peak fly season prevents the majority of cases with relatively low cost and management burden.

What You Can Do

Apply teat sealants to all cows at drying off to prevent summer mastitis
Use fly repellent products on dry cows and heifers during late summer fly season
Check dry cows and heifers weekly during summer for swollen quarters or systemic illness
Seek prompt veterinary treatment for any suspected summer mastitis case