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"
Daily weight gain : 500g
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