NCBC in recovery mode after IBR disease found at its AI stud
The highly-infectious virus, which causes respiratory disease, is thought to be present in 80% of Irish cattle herds. Strict EU rules exclude animals that test positive for IBR from official semen-collection centres, because carrier bulls may shed the virus in semen. The disease has ruled many bulls out of AI breeding, and made drastic action necessary after the NCBC outbreak, resulting in the slaughter of more than 60 bulls. In keeping with a policy of ongoing semen recovery from bulls, in case of future disease outbreaks, NCBC had build up enough semen for 2011 sales, said Eivers.
He said 15% to 20% more semen — which complies with EU veterinary regulation — had been collected from high-genetic value bulls, coming into this spring, than was collected for all of 2010. Staff at NCBC were collecting semen from new bulls in their bid to return to full production, working in co-operation with Department of Agriculture officials.
As the year goes on, farmers can use the ICBF active bull list to check availability of semen from NCBC bulls. Each bull on the list is rated medium, high or low for availability of semen. If semen from any bulls runs out, they will be taken off the active, bull new lists later this year.
Eivers said farmers would find it difficult to get semen from the top-rated bulls. He said if every farmer had his way, he would only use the top EBI-rated bull, so most AI organisations limit supplies of these per farmer, to give more customers a chance to buy their semen. This policy is in line with the advice from the Irish Cattle Breeding Federation that farmers opting for genomically-selected AI bulls use at least four of them in their herds, to compensate for the relatively low reliability of their genetic ratings. Seven of the top 10 rated bulls for EBI available in Ireland are genomically-selected.
It could be this time next year before the full effect of the IBR disease setback is felt in Irish cattle breeding. Even then, Eivers said, NCBC’s partnership with the multinational CRV AI company is expected to lessen the impact. In February of last year, NCBC and CRV launched Grassland Alliance, and said it was the largest, most specialised company selecting and selling AI suitable for grass-based milk production.
NCBC geneticists are searching for high EBIs in the genotypes of CRV bulls, with a view to adding them to their new bull line-up. In order to avoid inbreeding, they are also checking for relationship to bulls such as Oman, which dominate Irish dairy breeding.
Some of the CRV bulls are already on the active bull list, not having been affected by the disease outbreak at the NCBC HQ in Co Meath.
Eivers hopes some of the survivors in his stud will come through when semen from current top performers runs out. For example, he has high hopes for the likes of Derrinsallow 812 Arthur (DSU), not related to Oman, and already rated €221 for EBI.
