1.
Moshie Cohen asks:
The Background to the Daf references bison a number of times. This is highly unlikely, as bison are native to the US and Europe and have never been in E"Y. The "wild bull" would seem to be more likely translated as as "buffalo", as the water buffalo is native to the Middle East.
2.
The Kollel replies:
Shalom u'Vrachah,
Thank you for your thoughtful comment! Yes, bison would not have been present in the Middle East. Buffalo sounds reasonable, but from what I can see it looks like the water buffalo may not have reached west of Mesopotamia until the Arab conquests in the 7th century CE, after Talmudic times. On the other hand, the aurochs is a wild ox native to the region in ancient times, and therefore may arguably be an even better fit.
Bi'Vrachah,
Yishai Rasowsky