So why would two have it and not the rest?
Not sure I can answer that one for you, so let me state the agreed upon facts and see where it goes from there.
Fact:
1. a copper deficiency causes the redness
2. in cattle copper is ingested as are most all ( trace )minerals
3. copper is absorbed into animal
4. sulfur blocks the absorption of copper
now with that in mind:
Cattle producers have, over recent years, become well aware that high levels of sulfur molybdenum and other minerals in a cow's diet can affect her ability to absorb copper.
http://www.cattletoday.com/archive/2004 ... T345.shtml
That also is a proven fact.
Now this is where we move from fact, to investigation to attempt to answer your questions.
Another proven fact:
Copper Requirements in Cattle Cattle diets should contain about 4-10 parts per million (ppm) of copper, with calves on the lower range and cows at 10 ppm. Less than this amount results in a primary copper deficiency. Primary copper deficiency occurs when the basal diet is low in copper.
This indicates if the animal has an intake to low or to high.
Secondary copper deficiency occurs when there is an interrelationship with other minerals, most commonly sulfur, molybdenum, and iron. Diet and water sources high in S or Mo can interfere with copper uptake.
"intake" in this writing means "absorption" or the lack there of.
Bruce Anderson, DVM., Ph.D., and professor at University of Idaho's Caine Veterinary Teaching Center, says a number of factors can come together to produce a variety of problems. Copper deficiency can be primary (when intake of copper is inadequate) or secondary (when dietary intake is sufficient but other factors prevent utilization of copper in the body).
Again, secondary is lack of absorption.
Now, even with these facts, the reason I can't answer your question is, I don't know this animals primary and secondary intake history, from conception to present.
But you may be able to come up with your some theory of your own, as you do have some of her history for the period of time you have owned her and you know environmental conditions and your management practices.
By environment conditions I mean are you in a low copper and/or a high sulfur area.
By management practices I mean do you do any supplemental feeding and/or do you fertilize.
All of the above, and more can be found by googling : cattle, copper deficiency.
From there if you don't find a suitable answer, we can discuss some the ( unproven, not fact ) theories that are out there and are now under scrutiny.
Liz
