12 May 1995

Vital to stay on top of milk quality

ACHIEVING a low average cell count requires continuous effort, says Dorset herdsman Gary Harding. He is winner of the south-west large herds section of the Barclays Bank/NMR quality milk competition with an annual average of 37,000 cells/ml for his 125-cow herd.

He has been herdsman on David Foots Marsh Dairy, Littlemoor, Dorset, for 12 years.

Introducing Dairymaster automatic slurry scrapers set to clean the cubicle passageways 12 times a day, and daily bedding of the cubicles with chopped straw made a big difference to milk quality. But Mr Harding still spends time every day making sure the cubicles are clean, and scattering hydrated lime – a handful to three cubicles – once a week at the heelstone end.

Milking equipment is maintained regularly and checked annually using the full range of static and dynamic tests. The milking routine does not include taking foremilk, but teats are sprayed with teat dip.

Monthly cell counts are done by NMR on milk samples taken from each cow. Mr Harding thinks they are a good indication of sub-clinical mastitis infections.

When a cows cell count is over 400,000/ml but no clinical signs of mastitis can be found, no immediate action is taken. But when her next cell count is also high then the bacteria involved are identified and appropriate antibiotic treatment given in all four quarters for three consecutive milkings.

Once a cow has had more than three courses of antibiotics – whether for clinical mastitis or for sub-clinical as indicated by high cell counts – she will be culled. But that is only necessary for three or four cows a year.

"We are not achieving a low cell count by a high culling rate," he emphasised to visitors on a recent farm walk at Marsh Dairy.

&#8226 The herds NMR average is 7120kg at 4.02% fat and 3.17% protein. Current rolling margin over concentrates is £1305/cow, and margin over purchased feed and fertiliser is £3042/ha (£1232/acre).