Highlighting disease worries for cattle herds

BOVINE viral diarrhoea (BVD) and Johne's disease were the main topics at an animal health and welfare day held at West Plean Farm, near Stirling, on Tuesday and organised by the Scottish Agricultural College (SAC).

Farm hosts Tony and Moira Stewart and Moira's son Nicol Johnston are members of the SAC Premium Cattle Health Scheme. Their suckler herd has recently achieved BVD accreditation (two consecutive annual clear tests), and is also doing well with Johne's, which requires three clear annual tests for accreditation.

Eradication of BVD has been highlighted in the Pack Inquiry's interim findings, as part of the solution to falling Scottish breeding cow numbers.

George Caldow, manager of the Premium Cattle Health Scheme, told attending farmers: "Over a three-year period, there is nothing to stop us eradicating BVD from Scottish herds.

"This would enable Scotland to move to the forefront of the cattle industry within Europe, from a health point of view. Plus cattle performance – milk and meat would improve, generating more income for farmers".

BVD causes infertility, abortion, embryonic death, still births, weak and/or deformed calves and protracted calving periods. It also suppresses a calf's immune system, making it more vulnerable to scour and pneumonia. It is spread by "persistently infected" animals, which cannot be cured.

Shetland and Orkney have been tackling BVD for some time. Shetland has eradicated it, and Orkney, with the densest population of beef cows in Europe, is well on the way, with about 90 per cent of its 500-plus herds BVD accredited.

BVD can be controlled by an effective health programme, based on testing and vaccination, under-pinned with strong biosecurity.

Johne's is more complicated. SAC veterinary investigation officer David Gibson said:

"Johne's causes scour, which is unresponsive to treatment, causing weight loss, despite a good appetite. It also affects milk yield, impacting on performance of her suckled calf. The end result is a reduced productive life of the animal, particularly costly where expensive breeding stock are concerned".

He encouraged his audience to adopt a "test and cull" Johne's policy, reminding farmers that if an animal tested positive once, then it was sensible to cull it and not retain any offspring.