Brussel Sprout plant leaves

Anyone know if the leaves off the brussel sprout plant (not the sprouts or little cabbages themselves, but the actual plant leaves) are safe to feed to rabbits? I have collard greens and brussel sprouts planted near each other and can't at this point tell one from the other. Poor planning on my part, I know.

To the best of my knowledge the leaves are safe to feed, however take care because it's a plant that can cause gas so go easy on it I tended to avoid cruciferous vegetables as a general rule just to avoid possible issues.

First of all, our previous bunny and our now two baby flemmish babies eat an almost an entirely diet of green leafy vegetables. Munching pellets if they want. You can read Google articles about what to feed rabbits. It gets to be involved...for instance Kale is OK except in large amounts it puts too much calcium crystals in their bladder..etc. I think also for brussel sprouts....broccali..etc, I don't think it's good for them in large quantities..certainly no problem with a little bit here and there to vary their diet. ....Remember in their far long ago wild state, they were grass eaters and opportunistic leaf munchers.
Our rabbits have all the oat hay they want to eat, and their next vegetable is carrot tops (obtained from farmer's market), romaine lettuce, fennel leaves, cilantro , parsely, and of course, oat hay and course oat kernels. And pellets whenever they want.

Well, I gave them a leaf from the plant in question this morning and all seems to be well this evening. I am pretty sure it is a collard green plant, but if it was in fact a brussel sprout plant it did not bother them. Thanks to you both for your replies. I at least felt better giving it to them.