And yeah it's magnesium that male sheep need to avoid.
You want a feed that has as a *maximum* 2:1 ratio of calcium to phosphorous, preferably less, with no added magnesium. And preferably Ammonium Chloride (that is the additive they they add to protect the boys). And preferably salt too (sodium chloride) which will encourage them to drink more.
I found that manufacturers descriptions were rubbish and that feeds are designed for either ewes or rams (mostly just ewes), so I did a bit of research on the feeds available (to me) so that I could pick the right one(s) for my system. I did a spreadsheet 'un everything
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