Herniaria glabra with ducks?

[Venia Tulip]

Hey guys!

I was wondering if anyone knows if
Herniaria glabra (Rupturewort)
is dangerous for ducks (or chickens).

I want to us it in place of grass, but I'm nervous that it may not be something they should eat.
I would love to believe that if they shouldn't eat it, they wont.....but things dont always work out the way we want.

Thanks in advance!

Anna