Mishnayos Bechoros Perek 2 Mishnah 7

If one’s two ewes had not previously given birth and they gave birth to two males, both of them are given to the priest, as each is its mother’s firstborn. If one gave birth to a male and the other to a female, the male is given to the priest, as it is its mother’s firstborn. If they gave birth to two males and a female, one of the males is kept by him and one is given to the priest. Rabbi Tarfon says: The priest chooses the better of the two. Rabbi Akiva says: They assess the value of the lambs between them, and the priest takes the leaner of the two. And the second lamb must graze until it becomes blemished, at which point the owner may slaughter and eat it. And when the owner slaughters the animal, he is obligated to have gifts of the priesthood, i.e., the foreleg, the jaw, and the maw, taken from it. Rabbi Yosei deems him exempt from giving the gifts. If one of the two born together died, Rabbi Tarfon says: The priest and the owner divide the value of the remaining lamb. Rabbi Akiva says: Since there is uncertainty to whom it belongs, it remains in the possession of the owner, as the burden of proof rests upon the claimant. If they gave birth to two females and a male or to two males and two females, the priest has nothing here, as perhaps both ewes gave birth to females first.

שְׁתֵּי רְחֵלוֹת שֶׁלֹּא בִכְּרוּ, וְיָלְדוּ שְׁנֵי זְכָרִים, נוֹתֵן שְׁנֵיהֶם לַכֹּהֵן. זָכָר וּנְקֵבָה, הַזָּכָר לַכֹּהֵן. שְׁנֵי זְכָרִים וּנְקֵבָה, אֶחָד לוֹ וְאֶחָד לַכֹּהֵן. רַבִּי טַרְפוֹן אוֹמֵר, הַכֹּהֵן בּוֹרֵר לוֹ אֶת הַיָּפֶה. רַבִּי עֲקִיבָא אוֹמֵר, מְשַׁמְּנִים בֵּינֵיהֶן, וְהַשֵּׁנִי יִרְעֶה עַד שֶׁיִּסְתָּאֵב. וְחַיָּב בַּמַּתָּנוֹת. רַבִּי יוֹסֵי פּוֹטֵר. מֵת אֶחָד מֵהֶן, רַבִּי טַרְפוֹן אוֹמֵר, יַחֲלוֹקוּ. רַבִּי עֲקִיבָא אוֹמֵר, הַמּוֹצִיא מֵחֲבֵרוֹ עָלָיו הָרְאָיָה. שְׁתֵּי נְקֵבוֹת וְזָכָר, אוֹ שְׁנֵי זְכָרִים וּשְׁתֵּי נְקֵבוֹת, אֵין כָּאן לַכֹּהֵן כְּלוּם: