Cattle that are more resistant to TB have a greater ability to fight off the disease due to their genetic make-up. Just as genetics dictates how well an animal can produce milk or gain weight, animal health is also under genetic control. Farmers can breed cattle that are less likely to become infected with TB (i.e., more resistant), resulting in fewer TB reactors and fewer TB breakdowns.
TB costs the industry almost €100 million annually, so we all need to work towards reducing the rates of TB. Complimentary to other biosecurity measures, using breeding values for TB to breed more resilient animals will protect your herd against TB. Breeding for resistance to TB is complementary to existing control and eradication programmes which should accelerate the rate of TB removal from Ireland. To achieve the most profitable and healthy herd select cows and bulls for breeding that have the highest overall index (i.e., EBI, Replacement Index, or Terminal Index) with the lowest breeding value (i.e., lowest predicted prevalence) for TB resistance.
Each animal’s breeding value for resistance to TB is expressed as the predicted prevalence of TB in that animal’s progeny. Therefore, lower breeding values are more desirable. For example, a bull with a breeding value of 10% for resistance to TB is predicted to produce progeny where, on average, 1 in every 10 of his progeny will be diagnosed as a TB reactor, either during a whole-herd test or at slaughter.
Breeding values for genetic resistance to tuberculosis (TB) are available to view on HerdPlus via your EBI & Eurostar profiles.
Step 1: Log in to your HerdPlus Account
Step 2: Select ‘View Profiles’ -> and select ‘Beef Euro-Star’ or ‘EBI’
Step 3: Click ‘Excel’
Step 4: Check the last column ‘Health Traits‘ to view the breeding value for TB on the animals in your herd.
The importance of sire recording:
A sire is one of the most important pieces of data that can be recorded on any animal. Being able to identify a sire of an animal is vitally important from a genetic evaluation point of view. Without a recorded sire, ICBF is unable to fully use an animal’s performance in genetic evaluations. Particularly when it comes to evaluating TB resistance, it is essential that all animals that go down as TB reactors have the correct sire recorded. This identifies bulls that have a higher prevelance of TB affecting their progeny. Incorrect sire recording will inevitably result in animals getting a higher (i.e. worse) breeding value for TB resistance when it is not actually the case.
In the event that an animal in your herd goes down with TB, please check that the recorded sire is correct. If there is no sire recorded on the animal, go back through your records to ensure that the correct sire is recorded. Having a better understanding of the TB resistance in your herd is key to reducing/preventing cases on TB affecting your herd going forward.
If you require information on how to record sires or how to view the TB breeding values for animals in your herd, please call the HerdPlus office on 023-8820452 or email [email protected]