THE proportion of National Milk Recorded dairy herds in the higher cell count bands has reached 38pc, compared with 25pc two years ago.

November cell counts over the past three years show a big rise in herds with 201,000 to 300,000 cells/ml - 18pc in November 1999 but 26pc now. At the top of the scale, 4pc of herds had cell counts over 400,000/ml in November 2001, compared with 2pc in November 1999.

Mr Mike Blanshard of NMR said there was a general rise in cell counts. "This may partly be due to increasing herd sizes, and less individual attention," he said, "but the wetter and milder winters are also contributing to more environmental mastitis."

Extended lactations also contributed, as cell counts rose in late lactation, and restricted movements on farms meant cases due to be culled because of high cell counts had not been culled so promptly.

NMR is contacting farmers with high cell counts and encouraging them to carry out bacteriology tests to identify the pathogens involved so treatment can be accurate and swift.

Farmers not employing full recording services can take advantage of the new Ambic samplers designed for in-line parlours so they can get monthly cell counts.