Bekhorot 15: A Gazelle, a Hart, and the Limits of Permission

More on the consecration vs. blemish and their implications for practice, in terms of order: where is all this derived? From the different animals mentioned in the Torah, and how each of them teaches something new. Also, what about the exchange for blemished offerings? What about the offspring of blemished offerings? When can you redeem which? Are the offspring -- which can't be redeemed -- really subject to redemption? To sacrifice? Again, the timing (in this case, the time of conception in the context of the mother's consecration) matters.