Post by Shawn on Dec 31, 2016 17:23:26 GMT -5
Running with your personal theory a bit and comparing it to the official consensus - since stress does seem to be directly related to whether or not blv positive cows/calves actively develop tumors, poor immune response, etc - would it be completely ridiculous to wonder if what is actually identified by the test is something produced by the animals in response to stress itself. Therefore - just indicating that an animal is stressed instead of ill? That would seem a plausible idea to consider, especially since you have had calm, supposedly positive animals, deliver negative calves. It might also explain how a supposedly negative Dam could produce a calf that tests as positive. If so, how sad to ship animals that are merely stressed due to management issues. I would be interested to see how your personal theory plays out.
No, I can't go with you on that. Here's why. (All references by me are to blood tests) If you're talking about the ELISA test, it tests for antibodies, which means you've been exposed. If you've been exposed, but don't have it, you would not be positive on a PCR DNA test.
If you have the virus, the PCR DNA test will pick it up (in my understanding) regardless of whether the animal is stressed at the time or not. Because they HAVE the virus ALL the time, not just at times of stress.
Calves are infected in two ways: In utero or through nursing (most likely) during the colostrum intake time when their gut is open to good (and bad) stuff. NOTE: There is evidence that they can just as easily be inoculated by their + dam's colostrum, too. So it's not necessarily a losing situation to let a calf nurse from their BLV+ mother.
I am NOT in the medical field, but it's my understanding that human physicians do test for cancers via blood. Someone else, I'm sure, can chime in on that.