1) "KODSHIM KALIM" USED AS AN "ESNAN"
QUESTION: The Gemara concludes that an Esnan Zonah and a Mechir Kelev that were placed upon the Mizbe'ach must be removed because they are unfit to be a Korban, even if the owner sanctified them.
The Gemara in Zevachim (114a) explains that it is not possible to make an animal that is already Kodesh into an Esnan or Mechir Kelev. The only case in which it is possible for an Esnan or a Mechir Kelev to be sanctified is when the animal was paid to the harlot or exchanged for a dog while still in the womb of its mother, and only according to the opinion that "Vlados Kodshim b'Havayasan Hen Kedoshim" -- the offspring of a sanctified animal becomes sanctified only at birth (and not in the womb). In such a case, the animal became an Esnan or Mechir Kelev before it became Kadosh.
RASHI here (DH Hachi) adds that only the fetus of Kodshim Kalim can become an Esnan or Mechir Kelev and become sanctified.
What does Rashi mean? What is the difference between the fetus of an animal of Kodshim Kalim and the fetus of an animal of Kodshei Kodashim? Since the fetus does not become Kadosh until birth, it certainly may be traded or exchanged before birth, even if it is a fetus of Kodshei Kodashim!
ANSWER: The SIDREI TAHAROS and RAV SIMCHAH MI'DESVI explain Rashi's words in a simple way. There are only four types of Kodshei Kodashim: Olah, Asham, Chatas, and Shalmei Tzibur. The Olah, Asham, and Shalmei Tzibur must be male animals. Therefore, they obviously cannot give birth to any offspring and cannot have Vlados Kodshim. A Chatas may be offered from a female animal, but the offspring born to a Chatas is always unfit to be offered as a Korban, even when it is not made into an Esnan or Mechir Kelev, because of the Halachah l'Moshe mi'Sinai that offspring of a Chatas must be put to death. Since it is disqualified from being offered as a Korban, it must be removed from the Mizbe'ach if it was placed there, even if it is not an Esnan or Mechir. There is no need for the verse to teach that an Esnan or Mechir Kelev must be removed from the Mizbe'ach when it is the offspring of Kodshei Kodashim.
This is why Rashi writes that the Gemara must be referring to the offspring of Kodshim Kalim, such as Shelamim, which can be a female animal, and its offspring is valid to be offered on the Mizbe'ach!
(The MITZPEH EISAN, however, raises a question on this explanation. There is one case of Kodshei Kodashim which involves a female animal whose offspring is also valid to be offered as a Korban: a female animal that was made into a Temurah for a Korban Olah.)

41b----------------------------------------41b

2) ANYTHING THAT TOUCHES THE "MEKOR" IS TAMEI
QUESTION: The Beraisa (41a) discusses a case of a woman who underwent a difficult birth, bled from the womb for three days, and then gave birth through Caesarian section. According to the Tana Kama, her birth is considered to have taken place during her Yemei Zivah (the eleven days between the days of Nidah), and therefore she is a Zavah. RASHI (DH v'Yatza) explains that when the Torah says that the blood that flows as a result of the difficulty of childbirth is Tahor (see 36b) when the woman gives birth during her Yemei Zivah, this applies only to a normal birth. The bleeding from a Caesarian section is Tamei. Rebbi Shimon maintains that she is not considered a Zavah as a result of the birth. He considers a Caesarian section to be a normal birth, and thus the blood of "Koshi" is Tahor.
The end of the Beraisa states that blood that comes from there is Tamei according to the Rabanan, and Tahor according to Rebbi Shimon. Rav Yosef explains that the dispute involves a case in which both the baby and the blood came out through the Caesarian section. (Rashi explains that this differs from the dispute in the first part of the Beraisa, because this dispute does not involve the blood of Koshi, to which the Reisha refers in its discussion of blood that comes out of the womb before birth.) Rebbi Shimon and the Rabanan disagree about whether the womb, the source of the blood, is a place of Tum'ah ("Mekor Mekomo Tamei") or not. The Rabanan maintain that the Mekor is a place of Tum'ah. Rashi (DH Rabanan) explains that although the woman is not Tamei for seven days since the blood came out of the side of the womb, the blood itself is Tamei because it touched the Mekor and the place of the Mekor is Tamei. Rebbi Shimon maintains that "Mekor Mekomo Tahor" -- the place of the Mekor is Tahor. Therefore, blood that comes out of the side is Tahor, even though it touched the womb.
According to the Rabanan, why is the blood Tamei? Even though it touched the Mekor, that contact should be considered "Maga Beis ha'Setarim." The blood touched the Tum'ah in a "hidden place." The Halachah is that Maga Beis ha'Setarim does not cause what touched the Tum'ah to become Tamei. The blood, therefore, should be Tahor!
ANSWERS:
(a) TOSFOS (16a, DH b'Mekor) answers that it is possible that the rule of "Mekor Mekomo Tamei" is a Halachah l'Moshe mi'Sinai, and therefore the blood is Tamei even though it touched the Tum'ah in a hidden place. Tosfos proves that this must be a special Halachah l'Moshe mi'Sinai, because although the woman emitted Tamei blood she nevertheless remains Tahor, which also does not conform with the standard principles.
(b) The CHIDUSHEI HA'RAMBAN similarly states that the Mekor indeed does not make things that touch it become Tamei, because it is Maga Beis ha'Setarim. Moreover, blood is neither food nor drink, and thus it does not become Tamei through contact with Tum'ah. Rather, the rule of "Mekor Mekomo Tamei" is a Gezeiras ha'Kasuv: the Torah states that everything in the womb is Tamei, and, when it emerges, anyone who touches it becomes Tamei until nightfall (but not for seven days, which is the period of Tum'ah for a woman who bleeds).
(The Ramban's explanation is not consistent with the words of Rashi, because, as mentioned above, Rashi writes that the blood is Tamei because it touched the Mekor. Rashi earlier (22a, DH Isha) also writes that the blood is Tamei because it touched the Mekor. (See also RASHASH to TOSFOS 16a, DH b'Mekor, and the ARUCH LA'NER who understands that Rashi agrees with Tosfos.) However, it appears that the Halachah l'Moshe mi'Sinai was that the blood becomes Tamei only because it touched the Mekor; even though Maga Beis ha'Setarim is normally not Tamei, in this case the Halachah l'Moshe mi'Sinai teaches that Maga Beis ha'Setarim is Tamei.) (D. BLOOM)

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