Bekhorot 41A

גמ׳ תנא: קפץ העליון ולא קפץ התחתון, וכנגדו בגמל ניכר.

Talmud: With regard to the case in the Mishnah of the tail of a calf that does not reach the leg joint, it is taught in a baraita: This leg joint is the upper joint, between the thighbone and the tibia, and not the lower joint, between the middle and lower bones. And with regard to this upper joint, the corresponding bone in the leg of a camel is conspicuous, but in a calf it is not noticeable from the outside.

מתני׳ על אלו מומין שוחטין את הבכור, ופסולי המוקדשין נפדין עליהן.

Mishnah: For these blemishes enumerated in the previous mishnayot, one slaughters the firstborn outside the Temple and disqualified consecrated animals may be redeemed on their account.

גמ׳ הא תו למה לי? הא תנא ליה רישא: על אלו מומין שוחטין את הבכור! סיפא איצטריכא: פסולי המוקדשין נפדין עליהן. הא נמי פשיטא ⁠— מישחט שחטינן, מיפרק מיבעיא?

Talmud: The Talmud asks: Why do I need this additional statement that for these blemishes one slaughters the firstborn outside the Temple? It was already taught in the first clause, at the beginning of the chapter: For these blemishes, one may slaughter the firstborn animal outside the Temple. The Talmud answers that the latter clause of the Mishnah was necessary: Disqualified consecrated animals may be redeemed due to these blemishes. The Talmud asks: But this too is obvious; if one may slaughter a firstborn due to these blemishes, is it necessary to state that one may redeem them?

אלא, איידי דתנא שלשה הוסיף, ואמרו לו: לא שמענו את אלו, וקתני ואתי דיחידאה, וקא סתים לה בכולהו: על אלו מומין שוחטין את הבכור ופסולי המוקדשין נפדין עליהן.

Rather, since a previous Mishnah taught that Ila added 3 additional blemishes, and the rabbis said to him: We did not hear about those, and then the tanna of the Mishnah proceeded to teach halakhot in the name of individual opinions, those of R' Ḥananya ben Gamliel and R' Ḥanina ben Antigonus, one might have thought that the halakha is not in accordance with their rulings. Therefore, he states an unattributed ruling in this Mishnah with regard to all their statements: For all these blemishes enumerated in the previous mishnayot, one slaughters the firstborn, and disqualified consecrated animals may be redeemed due to them. This indicates that the halakha is in accordance with all of these individual opinions.