Bekhorot

It is one of the tractates forming Seder Kodashim (Hebrew סדר קודשים, "Order of Holy Things").

The examination of the blemishes of the first-born animal had to be done gratis (4:5,6), but an exception is made in favor of a professional veterinary surgeon, such as Ila (or Ayla; in Tosefta Bekhorot 4:11, Amlah).

Transfer of property is generally reversed in the Jubilee year; but what the first-born obtains by his birthright remains his forever.

In addition to names of blemishes, the Tosefta expands on different scenarios in which a Kohen may find himself when determining the status of a first-born, for example when a creature gives birth to an animal resembling another species.

In addition to the common theme of purity, the Babylonian Talmud expands on the exemption of the first-born Levite, or Kohen.