The masechet so far, chapter by chapter

Masechet Bekhorot details the laws governing firstborn animals, including the redemption of non-kosher donkeys and the sacrificial sanctity of kosher livestock. Through page 25, the tractate moves from donkey redemption and livestock birth doubts to physical evidence of prior births and prohibitions against shearing sacred wool.

Chapter 1 – הלוקח עובר חמורו: Redemption of the Firstborn Donkey

This chapter discusses the commandment to redeem a firstborn male donkey with a lamb. It outlines exemptions created by gentile partnership or priestly lineage. It also resolves uncertainties regarding birth sequence and sets the requirement to break the donkey's neck if it is not redeemed.

Gentile ownership or partnership in a donkey exempts its offspring from firstborn sanctity.
A firstborn donkey is redeemed with a lamb or kid given to a priest, a kohen.
When male and female twins create doubt regarding which emerged first, the owner keeps the lamb.
If an owner refuses to redeem a firstborn donkey, he must break its neck, performing arifa, and bury it.

Chapter 2 – הלוקח עובר פרתו: Firstborn Status of Kosher Livestock

This chapter covers male firstborn kosher cattle, sheep, and goats, which possess inherent bodily sanctity. Priests and Levites are obligated in these laws, though gentile partnership still exempts the animal. The text addresses physical oddities, caesarean births, and resolving monetary doubts between the owner and the priest.

Priests and Levites are fully obligated in the mitzva of firstborn kosher livestock.
Offspring born through a caesarean section are not considered firstborns because they did not open the womb.
When male twin births create uncertainty, the priest receives the leaner animal unless he can prove otherwise.
An animal that resembles a different species is exempt unless it displays some physical characteristics of the mother.

Chapter 3 – הלוקח בהמה: Prior Birth Indicators and Shearing Restrictions

This chapter establishes how to determine if a purchased animal previously gave birth, using physical evidence such as uterine fluid or nursing. It also details the Torah prohibition against shearing or benefiting from a firstborn animal's wool. The Sages debate procedures for clearing neck hair before slaughter and the status of shed wool.

A murky uterine discharge or expelled afterbirth confirms a prior pregnancy, exempting future offspring from firstborn status.
A nursing animal is presumed to have given birth because animals nurse only their own biological offspring.
One may pluck neck hair to inspect a blemish or make room for the slaughtering knife.
Sages debate whether wool that naturally shed from a blemished firstborn remains forbidden for use after slaughter.

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