If there are folks out there who graze cattle and sheep together, I'd love to hear how you provide mineral block access to the cattle without the sheep getting copper poisoning.
White salt,, and Icelandic Kelp. What I did,, though with Horses and sheep,, but same problem. Is each had their own pastures to go in at night. The sheep were not allowed into the horses area. The sheep area was set up in such a way, only the sheep could get in. They would just get their type of salt/minerals during the night. But if that will not work, the white salt,, and Icelandic kelp is a option.
Try to work out a position for the mineral block higher than the sheep can reach. Your cattle may only need sheep safe mineral anyhow if your forage has enough copper in it.
Sheep minerals out for everybody and bolus the copper, or work out some other way to get copper to the cows. That's what I do with my goats and sheep.
