Bechoros Daf 57 בכורות דַף 57

The next Mishnah states: הכל נכנסין לדיר להתעשר – all animals must enter the pen to be tithed, with the following exceptions: כלאים – a crossbreed (e.g., of a male goat and female sheep), a tereifah, יוצא דופן - one born by Caesarean section, מחוסר זמן – one lacking the time necessary before it is fit for a korban (i.e., it is fewer than eight days old), and היתום – an “orphan,” one whose mother died or was shechted before giving birth to it. Rebbe Yehoshua says that even if the mother was shechted and its hide is still intact, it is not considered an orphan, as the Gemara will explain. A Baraisa presents the derashos which disqualify the Mishnah’s listed cases from being used as korbanos. A gezeirah shavah between korbanos and מעשר בהמה ("תחת השבט" and "תחת אמו") teaches that these are also excluded from מעשר בהמה. Additionally, just as tereifah is excluded from מעשר בהמה (because an animal with a severed hind leg cannot “pass under the staff”), a tereifah is likewise disqualified from being used as a korban.

The Mishnah’s expression that “all” animals enter the pen for maaser means to include the cases in the following Baraisa: הרובע והנרבע – an animal who had relations with a person, or one with whom a person had relations, והמוקצה והנעבד – or one designated for idolatry or was itself worshipped, והאתנן והמחיר – or one given as payment for a זונה or as a dog’s exchange, or a טומטום or an אנדרוגינוס, all of them enter the pen for מעשר בהמה. [Rebbe Shimon exempts a טומטום and אנדרוגינוס.] Although our Tanna derives from the gezeirah shavah (תחת תחת) that animals disqualified as korbanos are exempt from מעשר בהמה, and the above cases are also disqualified as korbanos, the Torah specifically subjected these to maaser in the passuk: "כי משחתם בהם מום בם לא ירצו לכם" – for their corruption is in them, a blemish in them. Rebbe Yishmael’s yeshiva taught: כל מקום שנאמר בו השחתה אינו אלא דבר ערוה ועבודה זרה – wherever the word "השחתה" is said in [the Torah], it [refers] to nothing but immorality or idolatry. Since the passuk compares מומין with "השחתה", we derive that wherever a מום does not disqualify an animal (i.e., מעשר בהמה, which is sanctified even as a בעל מום), cases of "השחתה" are also not excluded from it.

The next Mishnah states: שלש גרנות למעשר בהמה – there are three designated dates for מעשר בהמה, as explained below. Rebbe Akiva says these times are בפרס הפסח – when it is halfway to Pesach (i.e., fifteen days prior), fifteen days before Shavuos, and fifteen days before Succos. Ben Azzai says the dates are the twenty-ninth of Adar, the first of Sivan, and the twenty-ninth of Av. Rebbe Elazar and Rebbe Shimon say they are the first of Nissan, the first of Sivan, and the twenty-ninth of Elul. [It is not the first of Tishrei, since it is Rosh Hashanah, and מעשר בהמה cannot be designated on Yom Tov.] Animals born in one year may not be tithed with animals born in another year. Tannaim debate when the new year begins for מעשר בהמה. Rebbe Meir says it is the first of Elul. Ben Azzai says: האלולים מתעשרים בפני עצמן – those [born in] Elul are tithed by themselves. He is uncertain if the year begins in Elul, like Rebbe Meir holds, or in Tishrei, like the third view in the Mishnah. Animals born before the "גורן" may be combined with those born after it; the law of גרנות is only that once the גורן arrives, one may not sell or shecht his animals until maaser is removed.