26 November 1999

Milk drop on the rise

INCREASING frequency of milk drop syndrome is being reported to Vet Lab Agency regional centres.

"There are a number of different things that can cause milk drop," says Graham David, VLA Shewsbury vet.

This includes viral infections such as respiratory syncytial virus (RSV), infectious bovine rhinotracheitis (IBR) and influenza. But it can also be due to ration changes, nutritional problems and wires from tyres in feed.

"The most common infectious disease causing milk drop is leptospirosis." There are many anecdotal reports of milk drop related to lepto and concern that its related to the reduction in vaccinations reported by vet suppliers. But this is yet to be confirmed in VLAs quarterly reports, adds Mr David.

"But milk drop could also be caused by IBR which needs to be identified straight away. When cows suffer milk drop call your vet in to investigate it."

Latest results from Schering-Ploughs bovine leptospirosis screening service initiative (BLiSS) show 40% of unvaccinated herds have evidence of being heavily infected with lepto. A further 41% of these herds test positive to infection, says the company.