Bovine Leukemia from Mom to Calf?

[Elkman]

We purchased some animals and one of them was losing body condition. So, we had the vet pull blood on her. The results came back positive for Bovine Leukemia and Bluetongue. This cow had a heifer calf in February. Since we're trying to build up our herd, we would like to keep her heifer, if possible. Our questions are:
• Is there a chance that the calf could be negative for Bovine Leukemia even though her mother tested positive?
• Also, how long after weaning do we need to wait to get accurate blood test results on the calf?
We're taking the mother and a steer calf to the sale barn, and we're torn between also taking the heifer calf to the sale barn or holding her for testing in the hope that she might be negative. She's a beautiful calf. Your assistance is greatly appreciated.

 

[Son of Butch]

• Is there a chance that the calf could be negative for Bovine Leukemia even though her mother tested positive?
Yes. Good news.
According to Merck Vet Manual more often than not the calf will be negative even though the mother is positive.
So at least the odds are in your favor. Upsets happen and long shots do come in, so for peace of mind test the calf.
• Also, how long after weaning do we need to wait to get accurate blood test results on the calf?
The manual doesn't address this question. My guess is 30 days, if at all, but that is just me guessing.

 

[Lucky_P]

Better than even chance that the calf is not infected... but don't count on it.
We don't routinely recommend testing calves less than 6-8 months of age... may have 'false' positive antibody test due to maternal antibodies.

Starting out, now that you know BLV is out there... would be a good time to develop best-management practices to lessen the likelihood of it spreading through your herd, if other animals are also infected, or you purchase in infected animals. No reusing needles between animals, no in-and-out of bottles of vaccine or medicine with a needle that's been in another animal, fresh new OB sleeve for each animal whenever palpating .

 

[Elkman]

Thank you very much for your information. Based on what you told us, we've decided to wait for 60 days and get a blood test done on the heifer calf. This was good news for us and we're hoping that everything will work out. Again, thank you!