2 August 2002

Strategy to fight abortion pays off

IMPLEMENTING a herd disease control strategy when bringing herds together to prevent abortions is cost effective, says one Hants vet.

Four years ago, the Bisterne herd suffered a breakdown in bovine viral diarrhoea, infectious bovine rhinotraceitis and salmonella after merging three herds, said vet Dave Coombes.

"Seeing losses of animals to salmonella and in-calf cows aborting at 6-7 months of gestation was demotivating staff."

Before the disease breakdown, BVD was already known to be present in the three closed herds, but no action was taken. Without any clinical problems, that was the right strategy at that time, said Mr Coombes. "But after the breakdown, a disease control programme was implemented with routine vaccinations against salmonella. BVD carrier cows are also identified by regular testing and removed from the herd."

Since its implementation, there have been no clinical cases seen. Mr Coombes believed it was cost-effective with the costs of vaccination so low. "The cost of one cow abortion is equivalent to the cost of vaccinating about 150 cows."

Despite the herd being IBR-free, vaccination against this disease was also included in the disease programme. This allowed purchased cows to be brought into the herd, increasing management flexibility, he added. &#42

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