Horses will founder in early spring on clover. As Mr van said we have to be very careful what we feed to horses. Paus, I never noticed if they were eating the flower tops of clover when this happens. I am thinking it is when clover first springs and do not know if the flower tops of clover are even out yet. Pregnant mares when ingesting fescue may aboard their babies. We always made sure our horse pastures were fescue free for this reason. Also if corn gets wet for a certain amount of time, changes are made in the corn. I do not know if it chemical or bacterial, but they will get what is called blind staggers, (a swelling of the brain) which wet corn does not seem to bother cows as far as I know as folks use to put corn in what is called, underground silos. Goats, from what I have been told can eat just about anything, I would not be afraid to feed pollen to goats, but would not for $ reasons I said before.