The emergence and evolution of Neolithic cattle farming in southeastern Europe: New zooarchaeological and stable isotope data from Džuljunica-Smărdeš, in northeastern Bulgaria (ca. 6200–5500 cal. BCE)

•Cattle and caprines were important in the Neolithic of northeastern Bulgaria, while suids were avoided.•Early in the 6th millennium BCE, post-lactation culling intensified and cattle became smaller.•δ18O and δ13C values of cattle tooth enamel show no evidence for an extended birthing season.•δ13C and δ15N values of bone collagen show that cattle grazed on C3 and C4 plants and were foddered.