Schmallenberg Virus (SBV): Is the virus circulating in herds and flocks in Scotland?
In autumn 2011 a new virus infection of cattle emerged in Germany and the Netherlands. This virus was called after the location of its first identification, hence Schmallenberg virus. It is spread by midges. The infection is relatively mild, but if it occurs during the critical stage of pregnancy, then the resulting calf, lamb or kid can be deformed.
In 2012 and 2013 Schmallenberg virus (SBV) spread across northern Europe with cases of deformed lambs and calves occurring in many parts of England, Wales and Ireland. A small number of SBV affected calves were born in Scotland in spring/summer 2013.
No disease was reported in 2014 and 2015 but in 2016 small numbers of cases were reported in continental Europe. This winter (16/17) cases were confirmed in England, Wales and Ireland. Cases are expected in Scotland, particularly in the southern parts.
SBV is spread by midges. As a result, spring calving suckler cows, dairy cows served through the summer and ewes tupped in August/September are most at risk from foetal abnormalities. There is also a risk associated with the purchase of pregnant dairy heifer replacements from Northern Europe.
Lactating dairy cows – milk drop (>25% loss of yield over one or more days) and increased temperature of 40°C or above, with or without diarrhoea, in three or more cows in a one week period.
All other cattle – pyrexia and diarrhoea in two or more animals, over three months of age, in a one week period.
Breeding cattle and sheep – SBV can cause foetal deformities if pregnant cattle are infected in the 3rd and 4thmonth of gestation and sheep in the 2nd month. Difficulty at calving/lambing (dystokia) is very likely due to foetal deformity
Your veterinary surgeon can collect the samples or arrange the submission of deformed foetuses required to diagnose the condition to the local DSC.