Combination Therapy Education

How many tubes does it take to clear up a case of mastitis? The answer usually lies on the side of the box of tubes. But for Kingston Maurward College’s herd, near Dorchester, it was an average 22 tubes per case – adding up to a staggering 2459 tubes in a year.

Costing out the time and hassle to treat each case – let alone the dumped milk and drug costs – meant that financial losses caused by mastitis were well above the national average of £100/case. So, as part of DEFRA’s Herd Health Planning Initiative, dairy herd manager Nigel Allen has worked with his vet Andrew Davies, of Southfield Vet Centre, to draw up and implement a comprehensive mastitis control programme. This 120-cow herd has been predominantly autumn calving, but is now switching to a level profile, producing 10,000litres/cow.

Changes in housing hygiene, milking routine and treatment have now led to a drop in mastitis incidence from 74 cases/100 cows/year to 56 cases. Cell counts have fallen from 175,000 cells/ml to 130,000 cells/ml – and just 576 tubes were used in a year. The previous 19% recurrence rate for cases is now just 5%.

As well as cutting the number of cases and improving the response rate to treatment, a key aim of the control plan was to reduce tube usage, says Mr Davies. A protocol is in now in place that uses mastitis tubes and injectable antibiotics,  in some cases. He explains that a quicker recovery with fewer relapses ultimately means that less antibiotic is used to treat mastitis. The new infection rate also falls because combination therapy cuts transmission rates and infection is reduced all round. “We are roughly halving the incidence rate at the moment and would like tube usage to be below 10 tubes/case,” adds Mr Davies.

“The main advantage of combination therapy is that you get penetration through the blood system, so more effective carriage of antibiotic to the udder. This particularly helps with chronic cases where a lot of scar tissue prevents antibiotic penetrating through the traditional route via tube. Combination therapy also maintains higher levels of antibiotics in the cow for a reasonable time; a compromise between drug costs and milk withdrawal periods.”

This is where using Cephaguard® LC plus Cephaguard® 2.5% injectable is often the treatment of choice for cases of E. coli mastitis. Because it is licensed combination therapy for E. coli, the milk withdrawal time is the same as for a tube alone: four days.

Mr Davies reveals that recent bacteriology of clinical cases (pre-treatment milk samples are routinely taken) has shown the presence of E. coli. “There were quite a lot of no growths too, which I suspect were also E. coli. The absence of Strep. uberis and Staph. aureus (both hard to control) is a major plus. We know there are not too many chronic cows infecting the rest of the herd, but this means we need to target improved management of the immediate environment such as cubicles and yards.”

Mr Allen was keen to try combination therapy after attending a farmer meeting on the topic. The indications so far are good, he says. “The clots disappear sooner. My objective was to stop cows from repeating. We have treated mastitis with tubes only for it to return 3-4 weeks later, and again 3-4 times in a lactation,” he says.

“In our 2006/07 production year, we had 13 cows repeating three or more times. Obviously the number one goal is prevention, but when we have failed in that, the priority is treatment to get the cow clean and not allow mastitis to repeat. I like the idea of hitting mastitis hard first time. The first go is the best one and if we can stop it repeating, we will soon get our money back.”

However, tackling environmental mastitis isn’t just a case of maintaining high standards seven days a week throughout winter. Mr Allen also has to consider the effect of several students and staff working with the herd. Hence written protocols, particularly for mastitis treatment, have always featured strongly at the unit. “Everyone can see clearly what to do.”

Because he likes to ensure a 30 second time lag between dipping and wiping, to stimulate milk let down, Mr Allen has arranged the milking routine to prepare cows in batches of either five or 10 depending on the number of milkers. “It requires discipline, but I like it and think it’s better for the cows.”

In addition, the parlour routine includes pre-dipping, post spraying and everyone wears disposable rubber gloves. Udder cleanliness has been much improved this winter with an udder singe. “We have treated all udders in this way, singeing back long hair and I’ve been very pleased with the cleanliness. Less straw and muck clings to short udder hair.”

Cubicle passages are scraped twice a day and mattresses bedded with chopped straw three times a week. The straw yard holding 25 fresh calvers and lame cows is bedded daily. “We use a cubicle disinfectant every day. Dirty wet bedding is raked out twice a day and clean straw brought forward. The straw yard is cleaned out completely every 3-4 weeks – if we go over this time, the yard heats up, becomes dirtier and mastitis increases.”