While we may only be a week or so into 2013, farmers who are still contending with the effects of flooding are now faced with the continued threat of the Schmallenberg Virus (SBV).
SBV affects sheep, cattle and goats. The symptoms of the virus include congenital deformities and nervous defects in newborn lambs, goat kids and calves. Clinical signs in affected cattle include pyrexia (fever), milk drop, and diarrhoea similar to what is often termed ‘winter dysentery’.
We need to make some decisions on how to deal with this disease. Over the last few years we have become used to dealing with Bluetongue in the UK, which is an entirely airborne virus spread by insects. It was well known in other parts of the world and a vaccination exists, whereas Schmallenberg is a relatively new virus with very little research completed on its cause and spread.
The disease has been associated with very mild to moderate disease symptoms in adult animals and late abortion or birth defects in cattle, sheep and goats. Based on distribution of the disease and experience with similar viruses, it appears highly likely that it is transmitted between livestock by biting insects such as midges and mosquitoes.
Unfortunately, perhaps inevitably, SBV reached the South West last year and spread rapidly. A vaccine is under development but is unlikely to be available until next year’s lambing season. In the South West, the lambing season is just beginning so we don’t yet know the full extent of the disease’s spread this year. No illness has been reported to date in humans exposed to animals infected with Schmallenberg.
I urge readers to continue to support their local farms throughout 2013; agriculture is the backbone of the South West and imperative to the future of our rural economy.