I dig a little in scientific publications about the "montanera" way of fattening pigs on acorns of Q. ilex rotundifolia and grass during months of november and december, here are some numbers :
Each pig eat 5-8kg of acorn and 2-2.5 kg of grass every day (fresh matter) (0.45 kg of grass DM)
>99.5% of bite was either for acorns or grass (50-50 or 60-40)
Daily volontary intake is (g/day) Crude protein : 230 Crude fibre 183 Crude fat 390
Yield / stocking rate :
* Yield of oak is 8-14 kg/year, so this means you need 0.3-1 oak (Q. ilex) / day / pig * Pasture yield 200–500 kg dry matter (DM) of the autumn grass production per hectare * One article says "A stocking rate of 0.76 pigs/ha was established so that the supply of acorns would not run out before the end of the fattening period"
At work there is building that has TONS of acorns around it every year. Since my husband is in charge of the maintenance of all of the grounds and buildings I know which areas have been treated with chemicals and which have not.
It would be great if I could find a use for all of those acorns.