R. Ami invalidated the sale where the buyer had sought fertilized eggs and the seller supplied unfertilized eggs (which cannot reproduce).

Question: That seems obvious!?

Answer: We might have obligated the seller only to compensate the buyer for the lower value of the unfertilized eggs under the claim that the buyer could have been understood as requesting (richer) eggs for eating, not eggs for reproducing.

Rav's statement (that an egg is completed upon exit) is alluding to the teaching of R. Yochanan that once an egg partially emerges it is permitted, even if it withdrew into the chicken and was only laid on Yom Tov.

Alternately, Rav's statement is disputing R. Yochanan.

(Tana Kama): These eggs may be eaten with milk.

(R. Yakov): If sinews connect the eggs, they are viewed as meat and may not be eaten with milk.

Question: Who taught the statement that one who eats from the clusters of eggs (Shalal) in the chicken is Tahor (not considered to have swallowed meat)?

Answer (R. Yosef): It could not be R. Yakov, since that would be inconsistent with his ruling that eggs connected with sinews are considered meat.

Question (Abaye): Perhaps Chazal only were stringent regarding the Isur of Basar b'Chalav but not regarding Tum'ah!?

Question: Why should they not have decreed regarding Tum'ah?

Answer: Such a Gezeirah would unduly increase the quantity of Tum'ah d'Rabanan in the world (causing an unnecessary loss to Taharos).

Alternate Answer: Perhaps the eggs to which R. Yakov referred are the Eshkol (which the Beraisa forbids) and the Shalal are nearly completed eggs.

Following this approach we construct the above steps as follows:

Question: Who taught that one who eats Eshkol of eggs is Tamei?

Answer (R. Yosef): It is R. Yakov who taught...

Question (Abaye): Perhaps Eshkol does not refer to the eggs, but to the Eshkol itself!

Question: What would be the news that the Eshkol itself creates Tum'ah!?

Answer: We might not have ruled them Tamei, like other generally non-eaten parts of the animal.

(Beraisa): Day and/or night, offspring are born at the time of day when the parents cohabit (as enumerated).

Question: What Halachic difference does it make that roosters cohabit and are born by day?

Answer: We may use this information to permit an egg which is found before Alos on Yom Tov (it must have been laid before Shekiah on Erev Yom Tov).

Question: How could R. Mari have ruled this way given that the person checked the nest before Yom Tov!?

Answer: We may assume that he didn't check thoroughly.

Answer: The egg had emerged and withdrawn, and could then have been re-laid at night (relying on R. Yochanan that once the majority has emerged the egg is considered laid).

Question: But R. Yosi b. Shaul citing Rav ruled that once he checked, an egg found in the pre-dawn of Yom Tov is prohibited!?

Answer: Rav was speaking about an unfertilized egg, where no cohabitation was involved (which could be laid at night).

Question: Then how could R. Mari be certain and permit the egg, why not suspect that it was unfertilized!?

Answer: The case was where a male was present.

Question: But that does not prove that the egg was produced from their union!?

Answer: A tradition teaches that chickens will not lay unfertilized eggs if a male is present.

Question: At what distance is he considered present?

Answer (R. Gamda citing Rav): So long as his voice can be heard by day.

R. Mari permitted an egg based on the presence of a male 60 houses away.

An intervening river nullifies the effect of a rooster.

A bridge nullifies the effect of a river.

A very thin bridge does not count.

Question: Then Rav should prohibit the egg (which could have been laid day or night) even if one had not checked before Yom Tov!?

Answer: Had he not checked we would (rely on the majority and) permit the egg as having been laid by day.

Question: Then we should assume that it had emerged and withdrawn and permit it even when he did check (like R. Yochanan)!?

Answer: R. Yochanan's case (the majority of an egg emerging and the withdrawing) is unlikely.

Tuma Shechika (pulverized garlic) must be treated as a liquid.

If left uncovered, it is dangerous.

Question: What is their rationale?

Answer: The fact that each is mentioned separately.

Question: How will Beis Hillel understand the separate references?

Answer: From each I would not have inferred the other.

Se'or is stronger than Chametz and we might have been lenient by Chametz had only Se'or appeared.

Chametz is edible and I might have been lenient regarding the non-edible Se'or.

Question: What will Beis Shamai do with R. Zeira's insight that Se'or and Chametz are the same?

Answer: All agree that they are the same regarding the amount eaten, but not regarding the amount requiring destruction (Beis Hillel does and Beis Shamai does not learn Bi'ur from Achilah).

This Machlokes regarding seeing Chametz is supported by R. Yosi b. Chanina and confirmed by the Beraisa.

Question: The Reishah and the Seifah provide contradictory implications regarding Beis Shamai.

HaShochet infers that slaughtering is only b'Di'eved on Yom Tov, but l'Chatchilah, without earth, one should not slaughter on Yom Tov.

By saying that one should not slaughter, Beis Hillel leads us to believe that Beis Shamai permits one to slaughter even l'Chatchilah!?

Answer: Beis Hillel mean to argue and teach that b'Di'eved one should not fulfill the Mitzvah of Kisuy, but that all agree that one should not slaughter l'Chatchilah.

Question: But the Seifah implies that only there Beis Hillel spoke about b'Di'eved, not earlier!?

Answer (Rabah): The Mishnah is indeed l'Chatchilah (not as implied by ha'Shochet), teaching one who is ruling the Halachah to tell the person asking:

(Beis Shamai): to slaughter, dig and cover;

(Beis Hillel): not to slaughter without ready earth.

Answer (R. Yosef): The would-be Shochet is told (according to Beis Shamai) to dig before the Shechitah.

Question (Abaye): Are R. Yosef and Rabah arguing over the teaching of R. Zeira citing Rav?

(R. Zeira citing Rav): One must place earth below and above the blood (proof text as analyzed).

R. Yosef would seem to subscribe to this requirement and earth must be dug prior to the Shechitah.

Rabah would seem to not subscribe to this requirement and he may dig after the Shechitah.

Answer (R. Yosef): All agree to R. Zeira's Din, and the Machlokes between us is whether one may slaughter without the earth under the blood already in place.

(Rabah): We are afraid to let a person dig the lower earth, lest he then decide not to slaughter.

(R. Yosef): We do not apply such a Gezeirah, lest one without lower earth (prepared) refrain from Simchas Yom Tov.