Pembrokeshire's livestock farmers are being urged to act now to prevent summer mastitis in their herds.
Data collected by the National Animal Disease Information Service has consistently shown a dramatic rise in cattle with summer mastitis from the second half of July onwards.
NADIS vet Mike Howe, who is based in Pembrokeshire, said the problem was often well advanced before farmers noted clinical signs because the supervision at pasture of maiden and in-calf heifers and dry cows was often sporadic because the summer was a busy time for farmers.
These signs, he explained, included gradual teat enlargement, flies clustering around the affected teat and obvious swelling of the quarter.
A rapid loss of body condition could be expected and abortion was not uncommon.
"Veterinary treatment is essential for these sick animals," said Mike Howe. "Despite antibiotic therapy and regular stripping of affected quarters, the affected glands will not be functional and will eventually become hard and indurated.
"The hopeless treatment response in summer mastitis emphasises the need for effective preventive measures."
A report written by Richard Laven, manager of the Scottish Agricultural College's surveillance centre, advised that dry cow therapy remained the most effective means of preventing summer mastitis both in cows at drying off and in susceptible pregnant heifers during the summer months.
"As a rule, the longer duration dry cow antibiotic preparations should be used, but only after consultation with a veterinary surgeon," said Mr. Laven.
In herds with a severe summer mastitis problem, re-tubing at three -intervals had proved successful, but was considered cost-prohibitive in beef cattle.
Mechanical barriers such as Stockholm tar or micropore tape had proven successful in the prevention of this disease in dairy herds during high risk periods.
Mike Howe suggested fly repellents, although providing useful protection against nuisance flies, could not be relied upon in isolation to prevent summer mastitis.