I see goats grazing in fields with hemlock. They'll give the hemlock a sniff and then avoid it while greedily eating everything else around it.
except grapes. They would arch up, intersect with his mouth, and... hit a tongue and roll off onto the floor.
turns out grapes (and raisins) are toxic to dogs. How they figure that out during the millisecond encounter with the tongue is mind-boggling.
oh, another one: one time when young I gave my dog a corncob to chew on, my theory being it would be like gnawing on a bone. and it he just ate it. it disappeared. we monitored him, he was fine, but scared me to death.
I grew up on a vineyard. Each harvest time the grapes would hang down heavily and almost touch the ground. Our pet dogs would park themselves beneath and greedily consume a whole bunch.
They would also scoff any dried grapes they found on the ground.
The worst effect seemed that they all would get noticeably pudgy during the season.