[12a - 29 lines; 12b - 26 lines]
We recommend using the textual changes suggested by the Bach, the Tzon Kodashim and the marginal notes of the Vilna Shas. This section is devoted to any other important corrections that Acharonim have pointed out in the Gemara, Rashi and Tosfos.
 Gemara 12a [line 23]:
"Amar Lei, Modina Lach" אמר ליה מודינא לך
This is the Girsa of Tosfos. Rashi's Girsa, however, is:
"Aval Modina Lach" אבל מודינא לך
 Rashi 12a DH Rebbi Shimon Omer Torim ד"ה רבי שמעון אומר תורים:
The words "keshe'Yavo she'Yagdilu" כשיבוא שיגדילו
should be "keshe'Yevi'em Achar she'Yagdilu" כשיביאם אחר שיגדילו (Ya'avetz)
 Gemara 12b [line 12]:
"Ha ka'Tani Lo Nehenin" הא קתני לא נהנין
The word "Ha" הא is unnecessary
1)[line 1][בשלמא] מזבח החיצון[BI'SHELAMA] MIZBE'ACH HA'CHITZON- Tosfos (11b DH bi'Shelama) explains that the Gemara must be trying to prove that the ashes of the Mizbe'ach ha'Penimi and the Menorah are both placed in the same pile as the Terumas ha'Deshen. Apparently, the Gemara inferred this fact from the Mishnah and is looking for a source for this practice. It is not entirely clear how the Gemara inferred this from the Mishnah (see Insights to 11b).
2)[line 2]והסיר את מוראתו ...V'HESIR ES MUR'ASO...- the entire verse is, "v'Hesir Es Mur'aso b'Notzasah; v'Hishlich Osah Etzel ha'Mizbe'ach Kedmah, El Mekom ha'Dashen." - "He shall remove [the bird's] crop along with its adjacent feathers (alt., intestines; or food in the crop) and shall cast it to the east of the Mizbe'ach, into the place of the ashes." (Vayikra 1:16)
3)[line 13]מחוסר זמןMECHUSAR ZMAN
(a)It is forbidden to offer an animal as a sacrifice before it is eight days old, as the verse states, "Shor O Chesev O Ez Ki Yivaled, v'Hayah Shiv'as Yamim Tachas Imo, umi'Yom ha'Shemini va'Hal'ah Yeratzeh l'Korban Isheh la'Sh-m" - "A bull or a sheep or a goat that is born, it shall be under [the care of] its mother for seven days, and on the eighth day and onward it will be acceptable as a fire-offering to HaSh-m" (Vayikra 22:27). An animal that is less than eight days old is called "Mechusar Zeman," since time must pass before it can be offered as a Korban. (See Background to Chulin 38:15)
(b)Our Gemara asks why the Rabanan do not rule like Rebbi Shimon (that the young Torin are sanctified and one transgresses the prohibition of Me'ilah if one benefits from them), since the Torin are comparable to an animal that is Mechusar Zeman, where all opinions agree that the animal can become sanctified before it is fit to be sacrificed.
4)[line 15]אין מום פוסל בעופותEIN MUM POSEL B'OFOS (EIN TAMUS V'ZACHRUS B'OFOS)
(a)In order for an animal to be brought as a Korban Olah, it must meet the requirements of the Torah (Vayikra 22:18-19) with regard to being unblemished (Tamus) and male (Zachrus). Similarly, a Korban Chatas must be unblemished and female.
(b)When a bird is offered for these Korbanos, though, it does not require those specifications. A bird-offering may be male or female, and it is only invalidated by a missing limb and not by a blemish. (This limitation is learned from the verse "Hakrivehu Na l'Fechasecha ha'Yirtzecha O ha'Yisa Fanecha..." - "[And if you offer a blind animal as a sacrifice, is this not evil? And if you offer a lame or a sick animal, is this not evil?] Try to offer it to your governor, will he be pleased with you, or will he find favor in you?..." (Malachi 1:8) — RASHI to Chulin to Chulin 23a DH bi'Vehemah.)
5)[line 24]וקשיא לי מי איכא מידי דמעיקרא לית בה מעילהV'KASHYA LI, MI IKA MIDI D'ME'IKARA LEIS BAH ME'ILAH ...- and it is difficult to me: is there anything that, at first, has no Me'ilah, and then, at the end, does have Me'ilah? (See Insights for a summary of the various interpretations of this question.)
6)[line 8]פרשPERESH- and the dung
7a)[line 17]קדשי מזבחKODSHEI MIZBE'ACH- with objects dedicated to be offered on the Mizbe'ach as sacrifices
b)[line 17]קדשי בדק הביתKODSHEI BEDEK HA'BAYIS- with objects dedicated to the property of the Mikdash (see next entry)
8)[line 20]קדושת דמיםKEDUSHAS DAMIM / KEDUSHAS HA'GUF
(a)An object with Kedushas ha'Guf is an object with intrinsic Kedushah, such as the utensils used in the Beis ha'Mikdash (RAMBAM Hilchos Me'ilah 6:5) or a live Korban that is used in the Beis ha'Mikdash "as is." An animal that has Kedushas ha'Guf cannot be redeemed without a Mum (blemish).
(b)An object with Kedushas Damim is an object the value of which is consecrated to Hekdesh; e.g. an animal that a person consecrated to be sold in order to buy with its value another animal as a Korban (even before the first one develops a Mum).
(c)An object with Kedushas Bedek ha'Bayis is an object the value of which is consecrated to Hekdesh so that it should be used for filling the day-to-day needs of the Beis ha'Mikdash, and not to be used for Korbanos.