Toseftá sobre Deuteronômio 12:15

All [animals that are] disqualified from being brought as sacrifices are sold in the marketplace and slaughtered in the marketplace, and sold by liter, except for first-borns and animal tithes, since their profit goes to their owners [rather than to the Temple]. Rabban Shimon ben Gamaliel says, a person may appease himself by liter (i.e., by weighing the animal himself), to know how much it weighs. Rabbi Yehuda says, a person may seek out his fellow in Jerusalem and say to him, "Did you eat today?" [If his fellow] says to him, "manna," then he knows that he ate from tithes, for just as manna has no monetary value, so too tithe has no value.^*in Jerusalem, one always spoke in hints (see Lamentations Rabbah 1:2) [If] he says to him, "summer fruit," he knows that he ate from a first-born, for just as summer fruits are sold cheaply, so too a first-born is sold cheaply. Beit Shammai says, only priests may share a [blemished] first-born amongst themselves, and Beit Hillel says, even with an Israelite. Rabbi Akiva permits [it to be shared] even with an idolater, as it is said (Deut. 12:15), "like the deer and like the gazelle." The meat of a first-born: Beit Shammai say, it may not be fed to a menstruant, and Beit Hillel say, it may be fed to a menstruant. A first-born that has a blood attack (see Bekh. 5:2), one may not let its blood even in a place that causes a blemish, but one may let its blood in a place that does not cause a blemish, the words of Rebbi. Rabbi Yehuda says, it may even be slaughtered on the basis of that blemish. Rabbi Shimon, even if it will die, one may not let its blood. [If] a first-born was coming after him, and he blemished it (i.e., in self-defense), if he intended [to cause a blemish], it is forbidden [to be eaten], and if not, it is permitted. As to all blemishes that are fit to have been inflicted by a person, Israelite shepherds are trusted, [but] shepherds who are priests are not trusted. [The Sages subsequently] went back and ruled as follows: One is trusted about [the first-born] of his fellow, but is not trusted as to his own. Rabbi Yehoshua ben Kefusai says, one may only slaughter a first-born on the testimony of two [witnesses]. Rabban Shimon ben Gamaliel says, even [on the testimony of] his son, and even his daughter. Rebbi says^*compare Bekh. 35b:5 ("Rabbi Yosei says"), even if there are ten people within his household [who testify about the blemish], they are not believed, for one who is suspected about a matter may not judge nor testify [about that matter]. They do not evaluate unblemished first-borns for an Israelite, but they evaluate blemished first-borns for them. [An expert] should not evaluate a first-born for an Israelite, but if a priest said to him, "Send me along with you," or in the case of who inherits from the priestly father of his mother, they may evaluate. A kosher (i.e., fit to perform Temple service) priest who was shepherding an Israelite's flock should not say to him, "Give me these first-borns"; rather, he may say to him, "Those four impure [animals] from your flock -- give them to me." All first-borns may be permitted by a person except his own first-borns, and he may be questioned about the impurity and about the purity of that which belongs to him.