Mystery leaf- Is it toxic to chickens?

[Armaget]

Hey everybody here in the gardening thread- does anyone know what this lovely leaf is, and if it's bad for chickens to eat? I found it in a small circular shape in the ground where many others were growing, in the form of one single leaf as the whole plant. I believe it is a type of spring plant, though as this is my first spring in my new house I'm not familiar with what grows there.
View attachment 2105798Here is my cat posing with the leaf in question

 

[Perris]

the photo link doesn't work; try again?
That apart, you can generally trust chickens' instincts to avoid what's toxic to them - it is not failsafe, but free ranging chickens are forever trying what they find, and they usually survive a taster.