Clean Bulls will pay Big Returns on Export Heifer sales
The outlook is for continued strong demand for our surplus Beef cross breeding stock through 2022.
The Chinese buyers require for the heifers to be mated at normal good mating weights (approx. 260+kg).
If export heifers have run with bulls without taking precautions, it significantly increases the risk that the IBR (Infectious Bovine Rhinotracheitis, or Bovine Catarrh) virus can be spread through the heifers. Heifers tested for IBR prior to mating have a 3-10% chance of being IBR positive, a few lines can still be majority or all positive as this virus can spread quickly in heifers under stress. After running with the bull, the rejection rate due to IBR can increase towards 40%, with 10-15% of lines being totally rejected. Hence to protect the export value of your heifers you need to be certain to use clean vaccinated bulls.
IBR virus is not of great economic importance in NZ as the heifers seem to rapidly recover from the mild flu like symptoms. Like human flu, it may knock them back for 2-3 weeks. A few cows that are persistently infected become spreaders of the virus. These cows often are "snorers" with snotty noses and may rub sticks up the nose to scratch the itch or inflammation in their nasal cavity. There is anecdotal evidence of more of these in Jersey herds, but I am not aware of any scientific survey on breed susceptibility.
In the export preparation process the heifers are tested to be free of the virus then are vaccinated against it so that they are protected for when they arrive in China.
So, what is the difference in value if a heifer is IBR positive or negative? Over the last 36 months there has been a substantial premium for heifers that are qualified for export. This includes other factors such as meeting the 6-month residency requirement on the same farm/s under one NAIT number. In beef cattle the export premium has been in the order of 10-30% increase in value over local market. Hence it is well worthwhile for farmers to confirm if their heifer mobs are currently clean of IBR and then to take some precautions with their bulls.
The recommended protocol for bulls is to test them prepurchase or at home. If they are IBR positive do not run those bulls with heifers that you may want to sell for export. If they are IBR negative, then follow through with the double vaccination protocol as soon as possible to reduce the chance that they will transmit the virus between heifers. "As an innovative exporter Genetic Development (NZ) Ltd is running a program to provide vaccinated bulls to our regular vendors", reported David Hayman, a partner in the growing export business.
"If a farmer wants to further protect this opportunity with heifer sales, then it may also pay to do some IBR screening on the heifer mob premating. A 10-15% sample may be sufficient to indicate if IBR is already present or not. If not present and vaccinated bulls are used, then there is a high probability that most or all the heifers can pass export testing protocols at any stage after mating".
To get further advice on testing and vaccinating bulls to maximize the health status and marketing opportunities for your heifers, contact your veterinarian or call our team.