maple seeds as feed?

My kids have been feeding maple seeds to the rabbit for the past week or so, which has got me wondering about their value as feed.  Has anyone tried feeding them to livestock?  Any info about their nutritional value or possible toxicity?  I'm not particularly worried, since I know maple leaves and twigs are okay, and he's doing just fine, I'm just wondering.
If they're nutritious and safe to feed in significant quantities I'll dry some to save for winter. 

They are nutritious and safe to eat!  For human consumption pick while still young and green.  Use in salads or cooked.  The older seeds are still safe and nutritious but become more bitter with age.  Still safe for animals if they find them palatable.  I've eaten sugar and silver maple seeds as above and boiled as a porridge.  As with all seeds/nuts (think wheat gluten and peanuts) there is always a possibility of allergies.  Eat one and wait a day before going whole hog.  I've never known anyone to react but it is possible.

Hooray!  I'll be drying some for winter.  Thanks.