[Avodah] buffalo

[Ari Zivotofsky via Avodah]

Eli Turkel via Avodah wrote:
> YD 28:4 discusses a buffalo. What animal are the mechaber and Rama 
> talking about (American Bison wasn't discovered yet)

they are likely referring to water buffalo, Bubalus bubalis, native to 
India.

They did not initiate the discussion - The Be'ar Hagola tracks the 
source of that halacha to the Agur (Rabbi Yaakov Landau, 15th century) 
who was quoting Rabbi Yishaya Ha'achron of 13th century Trani, Italy. In 
contemporary Italian the word buffalo is still used to refer to water 
buffalo, an animal that is raised domestically as cattle in parts of 
Italy. It is from the milk of water buffalo that mozzarella cheese was 
originally made near Naples, Italy, and in southern Italy it is still 
used to make "authentic" mozzarella cheese. This would lead one to 
suspect that Rabbi Yishaya Ha'achron, and hence also the Shulchan Aruch, 
were referring to water buffalo, and they had no doubt that it is a 
kosher behamah (domesticated animal)

see here for detals:
http://www.kashrut.com/articles/buffalo/