When I said "it's out there", I meant the disease is out there - not that the vet's wife had been discussing it in public. It's a disease that has been recognized for over 100 years, and has been widely disseminated. I'll bet it's not the first time it's been diagnosed in your county, herf.
regolith,
In a commercial beef herd, it may be more difficult to notice the economic effect - but it's there.
It's been studied more intensively in dairy cattle than beef; back in the early 1990s, a California study showed that MAP-infected heifers - still clinically normal - produced $250 less saleable milkin their first lactation than their non-infected contemporaries. 2nd lactation yielded $350 less saleable milk - and most didn't make it to a third lactation, as they broke with clinical disease or were culled for other reasons. Life span of a dairy cow infected with the Johne's organism is typically much shorter than for an infected beef cow - they're exposed to much more stress - and manure - on a daily basis, than are most beef cows.
If you were a purebred/seedstock producer, the diagnosis of Johne's Disease in your herd could potentially be an economic disaster.
Certainly, a reputable breeder would take the appropriate steps to try to 'clean up the mess' - and be upfront about herd status with potential buyers. But, even with testing/culling, it can take upwards of 10+ years to 'clear' a herd, if they've gotten to the point that they're experiencing animals with clinical disease.
Dr. Chris Rossiter's work with the NY Johne's program back in the '90s showed that in infected beef herds, calves born to a Johne's-positive dam were 10X more likely to become infected than calves in the same herd, born to non-infected dams.
