The torah, originally addressed to a more agriculturally-oriented community, has laws about livestock. First-born (male) animals of kosher species are to be given to the temple. First-born male donkeys, though not kosher, are specifically to be redeemed from the kohanim (priests). This reminds us of the killing of the first-born in Egypt.
(There is an analogue of this for first-born sons, called pidyon ha-ben, which observant families do.)
The obligation of pidyon petter chamor, redeeming the first-born donkey, still applies today, but is rarely done. A local rabbi wanted to perform this mitzvah, so he arranged to purchase some donkeys that were pregnant for the first time. (It only applies if a Jew owns the mother and thus the offspring at birth.) He did this through Kollel, who allowed people to buy shares in the donkeys and thus be able to participate. The last of the three donkeys produced an eligible foal.
I attended the ceremony today. (When am I likely to ever see this again?) The young donkey -- named Jacob -- was of course present, as was the sheep that would be used to redeem him. The basic idea is this: the donkey belongs to the kohanim by virtue of being a first-born male, but the owner of the donkey can pay a kohein to be allowed to keep his donkey. The torah-specified price of the donkey is a lamb or kid. The kohein can then do whatever he wants with the animal he receives.
(I have a video explaining the proceedings in more detail and another of the actual ceremony, but they're large enough to cut into my hosting quota, so I've taken them down.)
Some pictures: Read more…