DARD chief veterinary officer Bert Houston has told Farming Life that the coming weeks will be critical in determining whether the Schmallenberg Virus is gaining a stronger foothold here in Northern Ireland.
One case of the disease was confirmed in the Banbridge area last autumn.
“There have been a number of more recent Schmallenberg confirmations in the Republic of Ireland,” Mr Houston added.
“The reality is that the virus is now on this island. So it is not beyond the bounds of imagination to expect that the number of locally reported cases may well increase as we head towards the peak of this year’s lambing season.”
Schmallenberg can affect all ruminant species and has been particularly evident in cattle and sheep populations.
The virus itself gives rise to only mild symptoms in cattle which are transient including fever, drop in milk yield and sometimes diarrhoea. In sheep few if any signs are exhibited. If ruminant animals should become infected when pregnant, it can lead to abortion or malformations in the foetus. It is that latter aspect to the disease that is giving DARD veterinary staff most causes for concern, particularly where sheep are concerned.
Mr Houston continued: “The virus is spread courtesy of a midge, which acts as a vector. If ewes are infected prior to becoming pregnant then they will develop a strong natural immunity to the disease, which is likely to slowly wain over a period of years.
“However, breeding sheep that become infected while pregnant may well abort or give birth to malformed lambs. This is because the virus can cross the placental barrier.
“We are, therefore, asking local sheep and cattle producers to be aware of this disease and inform their private veterinary surgeon if they have any serious malformations or nervous signs in new born animals in their flocks or herds.”
The chief veterinary officer concluded: “While midges are regarded as the main vectors of the disease, other methods of spread may be possible and good biosecurity practices should be followed, especially when dealing with imported animals. This includes the single use of needles and good disinfection procedures when dealing with products of afterbirth.”
There are no human health implications associated with the Schmallenberg Virus, nor any food safety implications.