What are these berries? Toxic or not?

[margali]

That does appear to be the most likely suspect, although in the photo, I don't see thorns on the stem.
Silver nightshade

I think you nailed it. The younger stem have super fine thorns. I will be doing best to grub out and avoid.

 

[ducks4you]

I have these. I am pretty sure that they are toxic to livestock. If I remember, they have some thorns?
Get rid of them. Fortunately, they are not deep rooted.