משנה: הַבְּהֵמָה וְהַכֵּלִים כְּרַגְלֵי הַבְּעָלִים. הַמּוֹסֵר בְּהֶמְתּוֹ לִבְנוֹ אוֹ לָרוֹעֶה הֲרֵי הִיא כְרַגְלָיו: כֵּלִים הַמְיוּחָדִין לְאֶחַד מִן הָאַחִים שֶׁבַּבַּיִת הֲרֵי הֵן כְּרַגְלָיו. וְשֶׁאֵין מְיוּחָדִין הֲרֵי אֵלּוּ כַּמָּקוֹם שֶׁהוֹלְכִין׃ MISHNAH: Animals and vessels are like the feet of their owner96On a holiday a person may not leave his Sabbath domain. As on a Sabbath, on a holiday he may make an eruv teḥumim to move his Sabbath domain. Since on a holiday one may carry in the public domain, the eruv extends to all movable property of the person who makes it. That a thing is “like the feet of a person” means that it may be carried to any place accessible to that person but no other place.
Note that the grammatical plural בְּעָלִים means a single owner.. If he hands over his animal to his son or to a shepherd they are like his own feet. Vessels particular to one of the brothers in a common household are like his feet, but those not particular are like they place where they walk97If some of the members of the household made eruvin, the common vessels can be transported only in a domain accessible to all of them..
הלכה: מַתְנִיתָה בְּשֶׁמְּסָרָהּ לוֹ בְיוֹם טוֹב. אֲבָל אִם מְסָרָהּ לוֹ מֵעֶרֶב יוֹם טוֹב. כְּרַגְלֵי הָרוֹעֶה. בְּשֶׁיֵּשׁ שָׁם רוֹעֶה אֶחָד. אֲבָל אִם אֵין שָׁם רוֹעֶה אֶחָד. כְּרַגְלֵי הַבַּקָּר. וְתַנֵּי כֵן. הַמּוֹסֵר בְּהֶמְתּוֹ לַבַּקָּר אַף עַל פִּי שֵׁלֹּא הוֹדִיעַ לַבַּקָּר הֲרֵי זוֹ כְרַגְלֵי הַבַּקָּר. HALAKHAH: The Mishnah if he handed it over on the holiday; but if he handed it over to him on holiday eve it is like the shepherd’s feet. If there is there one shepherd, but if there is not one shepherd there, like the feet of the cow hand. And it was stated thus: “If he hands his animal to the cow hand even though he did not inform the cow hand it is like the cow hand’s feet.100An animal is like the feet of its owner only if the shepherd was not informed before the start of the holiday. This applies if there is a choice of shepherds (that there is at least one other shepherd available to compete for his business) and the owner did not make up his mind before the holiday. But if there is only one cow hand, the owner already knows that if he does not want to slaughter the animal that it will be given to that cow hand, it is as if delivered before the holiday and may be moved only to places accessible to the cow hand. Babli 37b.”