It could fall under the old phrase "too much of a good thing can be bad." I wouldn't feed them (or anything else) as a sole source of forage material, but the wind is always blowing hundreds of pods into my
chicken & pig pens each winter, and they seem to eat them when the opportunity arises with no ill effects.
It's similar with Nandina berries. Supposedly they're toxic and, while they do stay on the bush longer than things like beautyberry, they ultimately get eaten by birds/rodents once other food sources get scarce. I assume this is how they've gotten a reputation for being "invasive" in the south.
I'd just provide access to them as a component of the feed, and trust the animals to know if it's safe, and in what quantity; as they'll avoid toxic stuff(usually) if they have other options. My pigs will refuse to eat poke salad plants/berries if they have other things to eat, or will just nibble on it and leave the rest as to not overdo it.