Staying in control of contagious mastitis

Shortly after herd manager Dan Warman arrived at Rookhaye Estate, Bowerchalke, Salisbury, somatic cell counts averaged a massive 399,000 cells/ml with individual cows peaking at more than 1m.

Nineteen meticulous months later he has slashed the herd average to just 60,000 cells/ml and claims that there is no magic formula – just good old-fashioned hard work.

Mr Warman arrived at the estate in May 2004, five weeks after the preceding herd manager had departed.

“Quite a lot of damage was done in that period,” he says.

“When you fail to treat contagious mastitis it spreads like wildfire.”

The 344ha (850-acre) estate runs 140 mainly pedigree Holstein cows, 40 of whose cell counts exceeded 200,000 cells/ml and many of which exceeded 400,000 cells/ml when Mr Warman arrived.

“The first thing to do was find out what the problem was.”

Following bacteriology tests, Staph Aureus was identified as the cause behind 90% of the cases and Mr Warman set about changing herd management.

Cattle were housed on dry sand and all teats were pre-dipped, which was time consuming, he says.

However, as the problem was not Strep Uberis, which is caused by environmental conditions, he stopped pre-dipping and instead introduced dipping of clusters before milking, as well as post-dipping of teats.

“I have always dipped clusters – it is such an enormous part of why we got this under control.”

To make dipping easy for the milking staff he set up a bucket on a trolley.

“People have got to keep on doing it – it is essential all cows receive the same treatment.”

For a short time Mr Warman continued to operate a separate, high cell count group of cows whose milk was dumped.

“After taking out the worst 10 offenders the bulk tank reading fell from 399,000 to 108,000.”

Although 30 cows were culled for mastitis in the first year, Mr Warman introduced the five-point plan to treat useful cows and minimise unnecessary culling.

“Each case is treated differently.

We did many California Mastitis Tests to find out where the problem was.”

The estate’s culling rate due to mastitis has now fallen to just 10 cows a year.

“And our drugs bill has gone down enormously, plus we have reduced the costs of lower yields and other knock-on effects of mastitis.”

Mr Warman uses antibiotic injections and tubes to treat Staph Aureus, dealing with each quarter separately.

He prefers the active ingredient cefquinome and uses five tubes instead of the recommended three, with three antibiotic injections rather than two.

“We don’t get so many cows coming back with re-infections in the same quarter this way.”

Dry cows are also treated with cefquinome antibiotic tubes and a bismuth subnitrate teat sealant, with problematic young cows receiving a tilmicosin antibiotic injection.

When a cow fails to respond it is treated with a different antibiotic and when there is still no response it is either culled, the quarter dried off or the whole udder dried off, depending on the cow’s age, history and stage of lactation.

Recently Mr Warman has trialled udder singing to remove hair, to which sand, straw and other dirt sticks.

“It is used a lot in America and it really does keep udders much cleaner.”

The whole herd is NMR recorded and Mr Warman checks SCCs as soon as the monthly report arrives.

“It is the first thing I look at.

With quick detection of cases new infections really slow up.”

Good herd monitoring by staff is also vital and problem cows are routinely CMT’d every week.

Vet Keith Cutler of the Endell Veterinary Group also receives a copy of the NMR report and discusses the future course of action with Mr Warman religiously.

“It is important for the vet to be closely involved,” says Mr Cutler.

“But dealing with Staph Aureus is also down to hard work and doing things right and not taking short-cuts.”

Mr Warman agrees there is no secret formula for dealing with contagious mastitis.

“No one has got a cure to eradicate mastitis completely.

But when you do everything you’re told to do and know you should do, it will come right.

I just do my job meticulously every day – there can be no complacency at all.”