Does an Animal Nurse Another Mother’s Young?

Tannaim debate whether an animal nurses foreign offspring, determining the status of its future young and the prohibition against slaughtering a mother with its child.

The Case of the Nursing Animal

A Jew purchases a nursing female animal from a gentile, accompanied by the offspring nursing from her. Later, while under Jewish ownership, she gives birth to a male newborn.

The Torah mandates that the first male offspring to open a kosher mother's womb is sanctified as a בכור (firstborn animal). Does this newly born animal have the status of a firstborn, or does the prior nursing offspring prove that the mother had already given birth?

The Rabbis: Maternal Mercy Without Birth

In a ברייתא (external Tannaitic teaching), the Rabbis rule that the subsequent young is a ספק בכור (doubtful firstborn).

Their reasoning is that an animal may display maternal mercy (מרחמת) and nurse another mother's child even if it never gave birth,. Consequently, the nursing child might not be hers, leaving open the possibility that the newly born male is her true firstborn.

הַלּוֹקֵחַ בְּהֵמָה מְנִיקָה מִן הַגּוֹי, הַבָּא אַחֲרָיו בְּכוֹר מִסָּפֵק, מִפְּנֵי שֶׁמְּרַחֶמֶת אַף עַל פִּי שֶׁאֵינָהּ יוֹלֶדֶת.

In the case of one who purchases a nursing female animal from a gentile, the young born after it is a firstborn due to doubt, because she shows mercy even though she has not given birth. (Bekhorot 24a:4)

Rabban Shimon: The Presumption of Motherhood

Rabban Shimon ben Gamliel disagrees with the Rabbis, stating that the matter remains in its presumptive status.

He holds that an animal will never nurse any offspring unless she has previously experienced birth herself,. Even if the nursing young were adopted, the mother must have already given birth to another calf earlier. Whichever way you look at it, her womb has already opened, and the subsequent newborn is completely exempt from the law of the firstborn.

רַבָּן שִׁמְעוֹן בֶּן גַּמְלִיאֵל אוֹמֵר: דָּבָר בְּחֶזְקָתוֹ.

Rabban Shimon ben Gamliel says: The matter stands in its presumptive status. (Bekhorot 24a:4)

Slaughtering Mother and Child

The Gemara explores what turns on the exact interpretation of Rabban Shimon ben Gamliel's position. Does an animal that gave birth nurse only its biological offspring, or will it nurse a stranger's offspring as well?

This inquiry directly affects the biblical prohibition of אותו ואת בנו (slaughtering a parent animal and its child on the same day). If an animal nurses only its own offspring, one who slaughters both on the same day receives lashes. If it also nurses another animal's child, the relationship remains a ספק (uncertainty), and one does not receive lashes,.

The Halachic Resolution

Rav established a general principle that the halacha across the entire chapter follows the anonymous Mishnah. The Gemara initially objected that Rabban Shimon ben Gamliel's position is disputed by the Rabbis in an external baraita.

The Gemara answers that an objection found in an external baraita is not considered a dispute against the Mishnah,. Therefore, the halacha follows Rabban Shimon ben Gamliel: an animal that is nursing is presumed to have given birth, and her subsequent newborn is exempt from bekhorah,.

לְעוֹלָם אַדְּרַבָּן שִׁמְעוֹן בֶּן גַּמְלִיאֵל, וְהָא קָא מַשְׁמַע לַן: דְּבָרַיְיתָא לָא פְּלוּגְתָּא הִיא.

Actually, it refers to Rabban Shimon ben Gamliel, and this teaches us: A dispute in a baraita is not considered a dispute. (Bekhorot 23b:12)

An animal is presumed never to nurse unless she has previously given birth, exempting her subsequent offspring from firstborn sanctity.

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