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Is it safe to drink milk from a Johnes cow?

Posted: Sun Jan 15, 2017 11:58 am
by NewCowMom
We recently purchased our first family milk cow, and ran the 3 big tests...TB, brucellosis, and Johnes. She came back positive for Johnes. (via blood test.) The positive Johnes test also caused a reaction in the TB test. My vet said that a positive Johnes test can sometimes cause a reaction in a TB test, but that we need to have the state vet out to do a different TB test just to be sure. I asked about the Johnes test, if it could be a false positive, or if she could have been vaccinated previously, which (to my understanding) would cause a "positive" test. He said it's not likely, and that I should just ship for cull. The cow is 8 or 9 years old, and has NO clinical signs of Johnes. She's fat, healthy, and giving 4 gallons a day milking, with normal cow patty poop. She is the most gentle, patient cow...perfect for what we were looking for. I hate to just ship her and be out the testing costs ($240+) and the cow, and then have to start over. Should I just have the state out (no charge to me) to retest for Johnes and TB? And if she does prove to have Johnes, is her milk safe to drink raw? The studies on Johnes/Crohns seem to be mixed, with half saying Johnes will directly cause Crohns, and the other half saying they do not. Advice please???

Re: Is it safe to drink milk from a Johnes cow?

Posted: Sun Jan 15, 2017 8:36 pm
by dun
I wouldnt

Re: Is it safe to drink milk from a Johnes cow?

Posted: Sun Jan 15, 2017 9:08 pm
by farmerjan
There is so much information and counter information on Johnes and working with dairymen and all with the milk testing I hear every story imaginable. Realize that even if a dairy has animals that test positive for johnes, that they still can ship their milk.( It's the whole thing of not letting a calf suck from the cow and getting infected from contact with manure splattered teats and such.) Granted milk from a commercial dairy goes to pasteurization....
I have read more studies than not that do not directly link johnes to crohns disease. And there has been a recent study on a case of anti-biotics curing a case of crohns; listed in the university of Minn vet site maybe?
I would definitely get the tests redone. Then I would still question it as seldom does an animal reached the age of 8 or 9 without succombing to the disease. Do you have a family doctor that is schooled in wholistic health? I would ask them their opinion. Most want to crucify an animal if they have a positive reaction to anything. Johnes is also called paratubercullosis, so the positive to TB is a given if she does have johnes. But they can have false positives from TB tests. Had a guernsey that tested pos 3 different times to TB, yet each follow up test showed a negative retest. Finally quit worrying about it, drank her milk for years and buried her at 15 when she couldn't get up from arthritis in her joints. 30 years later I am still drinking raw milk from my cows. But that is only one small case. I honestly don't know what to tell you....

Re: Is it safe to drink milk from a Johnes cow?

Posted: Sun Jan 15, 2017 10:07 pm
by Bigfoot
Shoot craps if you just want to gamble.

Re: Is it safe to drink milk from a Johnes cow?

Posted: Mon Jan 16, 2017 2:23 am
by Son of Butch
First off, I'm impressed you did the testing (many don't bother)
While the cow checked all of the other boxes for what you wanted in a family cow it did fail 1 of your big 3.
You and your family's health is obviously important to you. While you probably can drink the milk without trouble,
I believe the uncertainty of not knowing for sure will leave you 2nd guessing yourself and cause you to wonder and worry.
Life is too short to bring worry upon yourself.
Give yourself peace of mind, cut your losses and ship her.

Re: Is it safe to drink milk from a Johnes cow?

Posted: Mon Jan 16, 2017 9:32 am
by Lucky_P
Mycobacterium avium subsp. paratuberculosis (MAP), the organism that causes Johne's Disease in cattle, is shed in milk/colostrum of infected cattle - it's not just in fecal contamination of teats that's an issue. Additionally, numerous studies have demonstrated that MAP survives pasteurization.

While the Johne's Disease/Crohn's Disease association is strong, it is still just that - a correlation/association, not a proven causation.

However, I personally would be inclined NOT to drink milk from a known positive Johne's cow... If she were going to be my 'family' milk cow, I'd have made a negative test result a requirement before I'd have purchased her... a positive test result to any of the 'big 3' would have been a deal-breaker.

Re: Is it safe to drink milk from a Johnes cow?

Posted: Mon Jan 16, 2017 10:12 am
by farmerjan
Have to agree with Lucky_P; to buy a family milk cow I would have made it a requirement that she pass those tests. It's a big investment for a family cow, then to have to do the tests yourself. I would still get the tests redone. Just for peace of mind. If they come up positive, then you need to make a hard decision and I think that it would be in your families best interest to not drink the milk. The studies do show that even pasteurization does not kill the MAP virus.
I am not so sure about the problems in the whole dairy industry with so much johnes now....It could have been stopped before it got to be a problem but it didn't and now there is a real problem. Alot of dairies do not test for it, but there are more that do if they are into registered cattle and sales. (ignorance is bliss???) I do know that it is a big thing in goats now and that testing for it is something that most all the ones who milk their goats do. The virus doesn't always get shed in the milk, and sometimes does not show up for years, but normally the animal will go through some type of "trigger" that will cause the virus to go from dormant to active and usually once that happens, they often get the clinical signs and go downhill from there. But they are still carriers if they don't ever show the signs. Even if you drank the milk with no problems, if you breed her and get a heifer calf, then it could not have the colostrum or anything like that....and I am not sure if the tests have ever shown that it can be transfered via the placenta....

Re: Is it safe to drink milk from a Johnes cow?

Posted: Mon Jan 16, 2017 1:30 pm
by Lucky_P
It's a bacterium, not a virus.
And yes, we've long known that it can cross the placenta to infect unborn fetuses in infected cows. R.Sweeney and associates at U.Penn, back in the 1980s, followed infected, high-shedding animals to slaughter and collected fetal tissues. They were able to isolate MAP from about 25% of those fetuses.
So... we routinely expect that daughters(or sons) born to infected cows are about 10 times more likely to be infected than a calf born to a noninfected dam in the same herd - whether by in utero exposure, oral exposure through organisms spread in milk/colostrum, or the constant exposure to organisms spread in the infected dam's feces.

Lots of good information at the UofWI page here: johnes.org

Re: Is it safe to drink milk from a Johnes cow?

Posted: Mon Jan 16, 2017 8:27 pm
by Chris H
Lucky_P, I've gotten into goats the last couple years in addition to the beef cattle. It seems many of the people with goats positive for Johnes are pasteurizing their milk and bottle feeding their kids. Are they just reducing their risk but not eliminating the risk of passing it on to the goat kids?

Re: Is it safe to drink milk from a Johnes cow?

Posted: Mon Jan 16, 2017 9:40 pm
by Son of Butch
Lucky_P wrote:While the Johne's Disease/Crohn's Disease association is strong, it is still just that - a correlation/association, not a proven causation. However, I personally would be inclined NOT to drink milk from a known positive Johne's cow...

If she were going to be my 'family' cow I'd have made a negative test result a requirement before I'd have purchased her
a positive test result to any of the 'big 3' would have been a deal-breaker.

Too late to undo the deal now. But excellent advice for anyone considering a "family" cow or goat in the future.

Re: Is it safe to drink milk from a Johnes cow?

Posted: Mon Jan 16, 2017 9:42 pm
by farmerjan
Lucky_P wrote:It's a bacterium, not a virus.
And yes, we've long known that it can cross the placenta to infect unborn fetuses in infected cows. R.Sweeney and associates at U.Penn, back in the 1980s, followed infected, high-shedding animals to slaughter and collected fetal tissues. They were able to isolate MAP from about 25% of those fetuses.
So... we routinely expect that daughters(or sons) born to infected cows are about 10 times more likely to be infected than a calf born to a noninfected dam in the same herd - whether by in utero exposure, oral exposure through organisms spread in milk/colostrum, or the constant exposure to organisms spread in the infected dam's feces.

Lots of good information at the UofWI page here: johnes.org


Sorry, wrong terminology

Re: Is it safe to drink milk from a Johnes cow?

Posted: Mon Jan 16, 2017 10:00 pm
by Workinonit Farm
I, personally, would not consume the milk from a known 'Positive' Johnes cow.

Re: Is it safe to drink milk from a Johnes cow?

Posted: Tue Jan 17, 2017 6:33 pm
by Lucky_P
I certainly wouldn't choose to - or go out of my way to seek out milk from a Johne's-infected cow.
But, the likelihood is pretty good that those of us purchasing commercially-produced milk at the grocery do occasionally ingest some live, viable MAP organisms. Are they a health threat? It remains to be seen.

Re: Is it safe to drink milk from a Johnes cow?

Posted: Tue Jan 17, 2017 9:12 pm
by Workinonit Farm
Lucky_P wrote:
But, the likelihood is pretty good that those of us purchasing commercially-produced milk at the grocery do occasionally ingest some live, viable MAP organisms. Are they a health threat? It remains to be seen.


Another reason I miss having my Jersey nurse cows, they were also used as our milk cows.

Re: Is it safe to drink milk from a Johnes cow?

Posted: Wed Jan 18, 2017 11:26 am
by farmerjan
If it's a bacterium and not a virus, how come it isn't killed by anti-biotics??? Not being a wise guy... I've always heard it preached that antibiotics are no good for a flu virus and such, but are what they give you, if you have a bacterial infection.