Combination Therapy

Dealing with recurring cases of mastitis is not just a drain on finances – it’s frustrating and depressing for everyone involved. But using a combination of inj and tubes to treat some clinical cases has proved effective at promoting a quicker recovery, as well as fewer relapses in Bill Turner’s 250-cow herd.

“In those cases, we saw a good rapid response to treatment with combination therapy and it is rare now for us to get a repeat infection,” says Mr Turner of Manor Farm, near Yeovil, Somerset. “Two years ago we had 30 cows at a time with mastitis: enough to form a separate milking group. We often found ourselves having to use 10 tubes to clear up a case and we always had cows calving in with mastitis. It was relentless.  The worst thing was treating a cow and she had mastitis again three weeks later, so I just wanted to hit it hard.”

His new treatment regime for the 8000litre herd, combined with an overhaul in housing and parlour routine, has helped reduce cell counts from 300,000 cells/ml to 131,000 cells/ml. The number of clinical cases has fallen from a peak of 110 cases/100 cows/year to 65 cases, and Bactoscans have dropped from 60-70 to 21. The key to changing mastitis management was a switch to a different vet practice. Jon Reader, from Kingfisher Veterinary Practice in Crewkerne spent time assessing housing, milking and parlour operations and came up with some areas for improvement.

“I looked at treatment regimes, managing cell counts (all cows with a cell count above 250,000 cells/ml had a CMT test) and dry cows. Bacteriology revealed mostly Strep. uberis causing clinical cases and high cell counts, with some Staph. aureus and E. coli cases,” says Mr Reader.

He points out the target for mastitis is 30 cases/100 cows/year with a 10% recurrence rate. However, his calculations showed that in 2005, Mr Turner was treating on average 20-25 cases/month – 40 cases in December alone. And the recurrence rate was 20%.

“Excessive tube use several times in a lactation, plus the amount of milk to be dumped soon increases the average cost of a case of mastitis,” says Mr Reader. “In fact, the biggest cost is not treatment, but milk withdrawal and milk lost. (The average lost in a lactation, subsequent to mastitis, is 250 litres – more in a higher yielding herd.) So you don’t want to have to do it all again in four months due to a recurrent case. And you can’t underestimate what all of this does to morale. We therefore wanted early detection and early treatment, then to hit mastitis hard using tubes plus injections, where appropriate. Cephaguard® LC plus Cephaguard® 2.5% injectable is licensed for E. coli cases, which means the milk withdrawal time is the same as for a tube alone – four days.”

After culling 8-10 chronic cows, Mr Reader suggested a number of both contagious and environmental control measures to put in place. The dry cow yard was a key source of contamination, housing 20 cows in a straw yard that was cleaned out every 8-10 weeks. Cows had to walk across the bed to get to the water trough, which was leaking. “We moved to monthly cleaning and replaced part of the yard with sand cubicles, putting the trough nearer the feed barrier. We also reduced cow numbers to 15 in this yard,” says Mr Turner.

“After Jon’s visit, we added pre-dipping to the milking routine, after foremilking, and wore gloves. ACRs were serviced and the dynamic test showed we had loads of vacuum leaks. We put in a new tank because regular and irregular fluctuations were causing liner slip and some teat-end damage in about 25-30% of cows. We did use a dedicated cluster for milking into the dump line and were rinsing it between cows, but now we disinfect it. We disinfect all clusters at the end of milking.”

These additions to the parlour routine added about 20 minutes to milking and it now takes two people two hours to milk 200 cows. But Mr Turner considers this worthwhile and is pleased with his better Bactoscans and lower cell counts. He changes liners after every 2500 milkings (three months) instead of 3600, and milks fresh calvers (the most vulnerable group) first. Mr Turner has since added another 50 cubicles and converted all milking cow cubicles to sand beds. Passageways are scraped out more frequently: twice a day, instead of just once.

Both he and Mr Reader continue to regularly sample for bacteriology and monitor cell counts on a monthly basis, CMT testing all cows with a high count. They then decide whether to dry a cow off early or not. He has adopted the belt and braces approach to drying cows off too: in addition to dry cow tubes, he uses a teat seal. “We can’t afford to replace cows if we have to cull because of high cell counts or mastitis. Fortunately, I think we’ve got on top of it now, although you can get a bit complacent after a while and let things slip.”

Mr Reader agrees. “The recurrence rate is now down to 10% and tube use over the past 12 months is down 15%. In December 2006, Bill only had 14 cases of mastitis and an average of five a month. These great improvements are due to combination therapy and Bill’s attention to detail – and lots of different changes across the board. The plan is to continue with these improvements because it is so easy to slip. People can be really strict at the start, but once times get busy standards can fall back.”