My 18 month old girl is doing well on just ad lib hay (no turnout at present, will change soon though) and I have been giving her suregrow past 10 months, anyone found suregrow to be 'heating'?
I have been using it on my 20 month old gelding and I have found it good and haven't found it to be heating. He has readi grass, sugar beet and sure grow. Plus as lib hay. He seems to be doing fine on that.
I suppose like many things it depends how much you feed. It is very high in protein but you feed such a small amount the protein content becomes irrelevant