8 November 1996

Attention to detail at all stages lowers cell count

Low bulk milk cell counts depend on careful management from cubicle to dispersal yard. Jonathan Riley reports

CELL counts of 80,000 achieved by the Elite herd at ADAS Bridgets are down to attention to detail from cubicle to dispersal yard, reckons Hants-based ADAS consultant Ian Ohnstad.

"There is no miracle method for reducing cell counts just careful management to ensure that when the cow is presented at the parlour all she requires is a dry wipe. But many milk producers still do not have an adequate routine or facilities to ensure this happens," says Mr Ohnstad.

"Cubicle backs must be brushed down every day, all the wet material removed and hydrated lime applied to help dry the back of beds and cut bacterial growth."

He suggests cubicles should allow a minimum width of 1.2m (4ft) between divisions and a depth of 2.4m (8ft) to offer a 700kg cow adequate lunging space.

Heelstones should be 18cm (7in) high to minimise the spread of muck on to the bed and heelstones of 10 to 12.5cm (4 to 5in) are only adequate in slatted housing.

"Air quality is often overlooked as a factor in reducing mastitis but high humidity caused by poor ventilation will increase the dampness of straw and encourage bacterial growth. Poor airflow is often indicated by the presence of cobwebs around the roof, so ventilation should be improved," he says.

"All passages to the parlour and the collecting yard should be clean and dry because as cows are moved in for milking, teat orifices begin to open making them vulnerable to infection from splashes of slurry."

Once in the parlour Mr Ohnstad advises that all cows are fore-milked into a container because any milk accumulation on the floor could encourage bacterial growth.

"A dry wipe is all that should be required before milking. After milking the teat and orifice must be dipped or sprayed so that they are completely covered. Finally the cow should stand in a clean, dry concrete floored dispersal yard for at least 25 minutes to allow the teat orifice to close fully before she is returned to the cubicle," he says.

"This daily management must be backed up by a strict culling policy." He advises that a cow should be culled when she has more than three incidences of mastitis in any one quarter or five incidences in total during a lactation.

Milk records will help to pinpoint which cows are responsible for increasing the farms cell counts.

"When three consecutive high figures occur find the affected quarter using a California mastitis test or by dropping milk into a mixture of one part washing-up liquid mixed with one part water. By finding the affected quarter and assessing which bacteria are present treatments can be better targeted and will be more effective and more cost-effective," he says.

Maintaining cell counts of under 80,000/ml at ADAS Bridgets depends on careful management, says ADASs Ian Ohnstad, so all the cow needs at milking is a dry wipe.



&#8226 Scrupulous cubicle hygiene.

&#8226 Fore-milking and dip/spraying teats.

&#8226 Stand for 25 minutes after milking.

&#8226 Good clinical record keeping.