dinosaur limb bone fragment from Lithuania

[D.N.FossilmanLithuania]

Good evening everyone!

 

Few days ago I found this bone fraction on the southern shore of Dusia lake, Lazdijai district, South Lithuania.

The maximum thickness is 6 mm, the thick layers and bone canals are also well visible. There were three times when I noticed very similar bone pieces in fluvial sandstone boulders of Siauliai district (Northern Lithuania) too. By me some limb bone cross sections of theropod dinosaurs look similar but I need professional ID of this bone taxonomy- I am sure it belongs to tetrapod, probably reptile or less likely mammal. 

Any opinion will be appreciated!

 

Best Regards

Domas     

[jpc]

is it really bright blue?  I can see some texture there, but hard to say if it is bone texture.  If so, it is just a rounded piece of bone and likely not identifiable.

[Fossildude19]

Size? Length, width?

I see the thickness is 6mm. 
Not sure you can say anything about this other than maybe bone.   

[Anomotodon]

Definitely not a theropod bone cross-section, they were hollow. Also I doubt it is a bone anyway - leaning towards a tooth of some fish with tubular dentine, like a hybodont (compare with well-known Asteracanthus). What age are these deposits?