There are new bovine viral diarrhoea (BVD) movement restrictions in place on breakdown herds and on individual females in those herds over 12 months of age.
For those in BVD breakdown situations, it is important to know that there are several ways in which the restrictions may be lifted, according to advice issued.
During the last year, the level of retention of BVD positives has been low, so the amount of virus circulating should be decreasing, according to Animal Health and Welfare NI (AHWNI).
It said: “However, the risk of the virus spreading is high in any herd that has had a positive result and so the purpose of the new restrictions is to limit the amount of damage that could be done to other herds.”
Herd level derestrictions
The AHWNI said that herd level restrictions will be lifted when two conditions are met.
The first is that for BVD positive (BVDP) animals, 21 days have passed since the last BVDP animal has been removed from the herd and associated herds (that is, the BVDP animal has either been culled or re-tested with a BVD negative result).
For BVD inconclusives (BVDIs), the animal has been culled, or has re-tested BVD negative.
Secondly, all animals in the herd and associated herds, except untested animals less than 31 days old, have a negative BVD status.
Once herd level restrictions have been removed, there are several ways in which the individual restrictions may be lifted, the AHWNI said.
Individual level derestrictions
It outlined that the individual female restrictions will be in place until one of the following conditions is met:
The AHWNI explained: “If you have individually restricted cows or heifers, the first step is to assess how far on in-calf they are and therefore how quickly they could be derestricted after calving.
“If you need to sell stock more quickly, getting your vet to take a blood sample for antibody testing may be most appropriate.
“Where BVD antibody testing has been carried out, the required results have been returned and the correct documents supplied to AHWNI, AHWNI will then inform DAERA that the required criteria have been met and will recommend derestriction.”
Preventing future breakdowns
The AHWNI said that the emergence of new outbreaks has frequently been linked to the introduction of new stock to
a herd.
“In breakdown herds that have not introduced cattle and where there was no contact with cattle from other herds during the susceptible window for infection, the key risk may have been from contaminated material being moved on to farms on equipment or people.
“Thorough cleaning and disinfection of pens, areas and equipment used by BVD positive calves is essential, to reduce the risk of virus spread within the farmyard and also to reduce the chance of the virus being moved off the farm.
“In herds that are free from BVD infection, responsible sourcing of calves, good biosecurity, appropriate use of vaccines, and an insistence on visitor hygiene will reduce the risk of the virus
being introduced.”
