The sooner you prune your plants after being deer browsed the better. That is because the chemical in the saliva immediately starts to work its' way into the plant. If you can't prune them within a few hours or a day of being browsed then it is too late to stop the chemical from working its' way into the plant. You don't need to prune much off of the plant, just the tip where the deer bit into the plant, not even a half inch. They can smell where the bulbs are and dig them up with their feet and noses.
Bulbs are an excellent source of food.
They are basically a refrigerator packed full of nutrients for the plant. That is why many bulb plants can bloom so early. They don't need to take a couple of weeks in the spring collecting food and water before they bloom. They already have their food stored in their bulb, so they are ready to bloom as soon as they wake-up from their winter dormancy. Daffodil bulbs contain a chemical that is poisonous.