With the increasing use of genomics and recording of sire details on the ICBF database, potential AI sires in dairy herds are now routinely identified prior to their being born, it says.
It is expected that this will increasingly become the norm for beef sires in 2015 and beyond.
Ultimately, only a small proportion of these calves will be purchased by AI companies and enter semen collection centres, with IBR test results being the basis on which some will be rejected.
AI companies will preferentially purchase calves that are antibody test negative at (or before) 42 days of age. Early identification of these calves gives the greatest opportunity to manage both the calf and its dam appropriately, both before and after birth, to ensure
that this is the case.
Essentially this requires appropriate management to ensure that the calf does not get infected with the virus, either from its dam or other animals in the herd, and does not receive colostrum that has come from an IBR-positive cow.
The specific steps needed to achieve this will vary depending on the status of both the herd and the dam, being most straightforward in non-vaccinating, IBR free herds.
Animal Health Ireland has recently produced a detailed guide for the management of potential AI sires identified in dairy herds, and will shortly publish a similar guide for beef herds.