I sold a buckling to a woman a couple of years ago with whom I became friends. She also bought one of my doelings later. I had tested the buckling's dam for CAE, CL and Johnes when the buckling was about 5 months old and too young to test. Well recently she had an interested buyer for this buck but they wanted him tested. His tests came back positive for CAE AND CL. Her vet and websites where we've done research say that he could only have gotten it from his dam. However, the buyer for the buck also owns this buck's 1/2 sister (same dam which I own) and she has never tested positive either. My doe has been tested every year and is always negative. Could he (the buck) have gotten it from does he has bred that were positive? Or could the test simply be wrong? Some discussion would be appreciated tremendously!
You need to be a member of Nigerian Dwarf Dairy Goats to add comments!
Replies
Yay! Congratulations!
Julia,
That is great news!
-Michael
Well, turns out no one has CAE, not the buck with the false positive, or my doe or her doeling. Was such a crazy thing... but all's well that ends well. Everyone is clean and disease free. Also buck tested Negative for CL. So both results were mistakes. The first lab was very apologetic-- says samples must have been bad. I sent mine to a third lab. All clear and very relieved.
Thanks everyone for your input. Sending off samples in tomorrow's mail. I will order the PCR test for my doe but test the rest with Elisa. Fingers crossed everything is okay.
Here we go. According to this transmission via breeding is considered unlikely, but it can be transmitted by blood. http://www.merckmanuals.com/vet/generalized_conditiorthritis_and_en...
"The chief mode of spread of CAE is through ingestion of virus-infected goat colostrum or milk by kids. The feeding of pooled colostrum or milk to kids is a particularly risky practice, because a few infected does will spread the virus to a large number of kids. Horizontal transmission also contributes to disease spread within herds and may occur through direct contact, exposure to fomites at feed bunks and waterers, ingestion of contaminated milk in milking parlors, or serial use of needles or equipment contaminated with blood. Unlikely methods of transmission, as indicated by experimental studies, include in utero transmission to the fetus, infection of the kid during parturition, and infection through breeding or embryo transfer."
This is also an interesting and short read, which I had forgotten about until I came across it while looking for the above links. "Mygoat" (Dona) is very knowledgeable and is actually studying to become a caprine vet right now. Apparently certain strains of CAE can be transmitted by droplets from the lungs, as can OPP (a closely related disease of sheep which also infects goats). I believe the test at WADDL detects both CAE and OPP.
http://www.homesteadingtoday.com/livestock-forums/goats/533385-cae-...
A quote from the article Dona linked in that discussion:
"Seropositive sheep and goats must be considered infected and capable of transmitting the virus. Transmission occurs most commonly via the oral route, usually by ingestion of colostrum or milk that contains virus, or by inhalation of infected aerosol droplets. Intrauterine infection is thought to occur infrequently. All breeds of sheep and goats appear susceptible; however, some resistance to lentivirus infection may exist within breeds. Management practices can influence morbidity rates."
http://www.merckmanuals.com/vet/respiratory_system/respiratory_dise...
I'm sorry for the overabundance of links and quotes. I spend a lot of time researching these diseases. I really find it interesting and also useful since I (obviously!) want to keep them out of my herd. Knowledge is our first line of defense against goat diseases. :)
Here's the link to that conversation. I misspoke; her twins were dam-raised, and one was + and one -.
http://www.homesteadingtoday.com/livestock-forums/goats/535288-cae-...
Other possibilities, in addition to false results...he could very well have nursed another doe after being sold. It's not unheard of for older goats to still try to sneak a snack. If he was ever vaccinated for CL, that would cause false positive for that test. It is also possible in rare cases for CAE to be spread via blood -- I'll try to find what I was reading about that just the other day -- which could, in theory, allow exposure during mating. CL can also occur in the lungs or udder, allowing the spread without an obvious abscess.
I agree that you should retest, though! If both your herds are and have been clean, it seems unlikely he should convert. Unless perhaps he was exposed to another goat at some point not from your herds.
I will add that I also read something just the other day about a person with a CAE+ doe who had twins, both of which were raised on CAE prevention, but one converted later on and the other didn't. Again, I'll try to find that conversation for you!
Yes, the ELISA can have false positives. About 1% of the positives are false, according to the pathologist at WADDL. You can have a PCR done at Colorado State, and that is supposed to test for the actual DNA of the disease. The reason people don't do PCRs routinely is because they're $25 a test, rather than $5 a test for ELISA.
I haven't heard of a false positive on a CL test, but why not? You can call the pathologist at WADDL, and he (or she) can discuss your particular situation.
Thanks Michael. It just doesn't make sense unless it's wrong. But why a buck would have antibodies show up... I don't know. And CL too? None of her herd have shown any signs of CL whatsoever. I am trying to get someone to come over and help me draw blood again and send it off. I read about a "PCR" test that can pick it up if it's dormant. My vet is out of town -- he helped me last time. This doe is not due until June but I need her tested before then. She's 6 years old and been tested every year.
-
1
-
2
of 2 Next