The ewe tells you how much milk it produces per day--"Milk quantity."
I think the exact number is around somewhere. I believe the lamb drinks half of what the mother produces at base quality levels. As milk quantity goes up, there will be more to collect after the ewe feeds the lamb(s).
If you remove the lamb from the ewe, they will starve, and if it doesn't kill them, then it'll seriously hurt your attempts at quality.
Cheese production is just like everything else--time. Time to increase quality, time to increase quantity.
Relative RoB article:
http://ringofbrodgar.com/wiki/Animal_Qualities (Note: the page still mentions ESV values... these can be ignored and are no longer in game.)
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