The Department of Agriculture Food and the Marine (DAFM) is urging the investigation of any birth deformities seen in calves or lambs this spring.
The DAFM’s Regional Veterinary Laboratories (RVLs) have detected an uptick in the number of confirmed cases of Schmallenberg virus (SBV), a midge-borne virus that can cause birth deformities in calves and lambs.
Agriland previously reported on these cases of SBV last week, as two SBV positive test results were recorded last month in lambs in Co. Wexford.
According to the DAFM, when SBV was detected first in Ireland in 2012, the impact of the disease was short-term, after immunity built up in cattle and sheep (through exposure and vaccination).
Since then, there have been a small number of outbreaks, and the DAFM has described SBV as “a low-impact disease overall,” except on a small number of farms where animals were infected at the stage of pregnancy when the foetus in-utero is most susceptible to the effects of the virus, which results in the birth of deformed off-spring.
While SBV is regarded by the DAFM as “a low-impact virus,” the RVLs are emphasising the value of ensuring that deformed calves and lambs are submitted to them for testing, to increase the surveillance for both SBV and the “potentially more impactful” bluetongue virus (BTV), according to the DAFM.
Both viruses can result in the birth of deformed off-spring. Bluetongue has been detected in the UK and in Europe in the past year.
Bluetongue would risk causing significant animal welfare impacts as well as trade challenges if it became established here, the DAFM has stated.
Both viruses can cause a wide variety of birth deformities, especially deformed limbs (arthrogryposis), spinal curvature (scoliosis), torticollis (twisted neck) shortened lower jaw (brachygnathia inferior) and domed skulls (hydranencephaly).
Some of these birth deformities can make natural calving or lambing very difficult and farmers should be alert to an increased risk of these ill effects in this season.
Bluetongue virus could come to Ireland through the wind-borne spread of infected midges, through the importation of infected animals or contaminated fomites or animal derived biological material (e.g. blood, semen).
Farmers are advised to be vigilant and to ask their vet to refer any birth deformities in sheep or cattle to the nearest RVL for investigation.