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"Poisonous" does not mean deadly. Some manifestations of toxicity are subtle. The dose, as always, determines if a plant is safe source of nutrients or a toxic hazard.

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BRIEF: How to treat Steely Wool Syndrome in sheep?

I've been assigned a research paper on "Steely Wool Syndrome" AKA Cu deficiency. I understand the pathology of the condition and why it occurs, yet am a little unclear on how to treat once symptoms surface. It is known that supplemental feeding of Cu in a deficient diet is very risky since sheep are so susceptible to Cu toxicity. I am also aware that once symptoms arise, it is a good indication of not only rumen & blood Cu depletion, but also deactivation of irreplaceable Cu enzymes. My research requires dealing with an imaginary sheep herd suffering from Steely Wool Syndrome" - which has prompted me to ask some reliable sources what actions must be taken in such a situation??


Wow, I just lectured on this in my Nutritional Toxicology class! Plus, I actually observed this in my own flock at home a few years ago. I guess I was lucky. A mild form of steely wool was the only symptom I observed, with no other complications. Silver color and coarser texture was about it. What happened in my case was that I was so careful to avoid added copper in my sheep diet that, together with naturally occurring low Cu forages, I caused a mild deficiency. Had these sheep been challenged with a number of selected toxicants or stresses, I might have seen more symptoms, but they were otherwise fine. All I did was shear them, then allow them access to red trace mineralized salt with copper in it (the kind we don't usually feed sheep anymore), and the fleece grew in quite black and fine after that. I still limit the copper intake and make very sparing use of salt with Cu in it, but make sure there is enough. Higher Mo in the soil, or high protein (and therefore high sulfur) diets can increase the requirement for Cu, as you no doubt know.