Bechoros 20

We have a discussion in this Perek about Sfekot, cases where we're not sure what happened.

The first Mishnah here discusses a case where you purchase an animal from a Goy, and that Goy is not trustworthy, and then the animal gives birth.

You're not sure if this child is the firstborn and is Chaiv in Bechor, or it's not the firstborn.

So the question is, do you treat it as definite Bechor, definitely not Bechor, a Safek, et cetera? So there's Machloket, Rabbi Yishmael and Rabbi Akiva in the Mishnah.

Rabbi Yishmael came and said, "It's very simple.

We can give you a Shiur in zoology.

Goats do not give birth more than once in their first year.

Sheep do not give birth more than once in their first two years, and cows and donkeys do not give birth more than once in their first three years.

And therefore, if you can trust the goat and the age, or you can tell the age just by looking at it, then if a goat gives birth in the first year, you know it's a Bechor, and you're not worried that it's the second kid.

Same for sheep, same for donkey, and cow." Now we s-- And then Rabbi, Rabbi Akiva says, "Not so simple.

You can also have miscarriages in that same year, and the miscarriage, while it's not a healthy child walking afterwards, it's still enough to exempt subsequent births from Bechor.

And therefore, this rule of Rabbi Yishmael might be true, but it doesn't prove that it's not a Bechor." Great.