Chulin 5:3-4

Chulin 5:3

If a person slaughtered an animal and it was subsequently found to be a treifa, or if he slaughtered it in the name of an idol, or if he slaughtered a cow intended to be used as the parah adumah, an ox that was to be stoned, or a calf whose neck was to be broken as an eglah arufah, Rabbi Shimon exempts him for violating the prohibition against slaughtering an animal and its young on the same day (because this slaughter doesn’t count); the Sages declare one liable (because the animal was nevertheless slaughtered). If, while slaughtering, one rendered the animal neveila, or if he stabbed or tore it, he is not liable for violating the prohibition against slaughtering an animal and its young on the same day (because there was no slaughter in these cases). If two people bought a cow and its young (separately), the one who purchased first has the right to slaughter first; if the other person slaughtered first, then the first person must wait until the next day. If a person slaughtered a cow followed by two of its calves on the same day, he receives 80 lashes (for two violations of “it and its young”). If he slaughtered the two calves followed by the cow, he receives 40 lashes (since slaughtering the mother was a single act). If he slaughtered the mother, then its calf, and then the calf's calf, he receives 80 lashes (for two violations of “it and its young”). If he slaughtered the mother and its calf's calf, followed by its calf, he receives 40 lashes (because slaughtering the animal that was offspring to one and parent to the other was a single act). Sumchos said in the name of Rabbi Meir that this latter person receives 80 lashes (because he violated two prohibitions – one for its parent and one for its offspring). Four times a year, one who sells an animal must inform the buyer that he sold the animal’s parent or offspring to be slaughtered: the day before Shemini Atzeres, the day before the first day of Passover, the day before Shavuos and the day before Rosh Hashana; Rabbi Yosi HaGlili also included the day before Yom Kippur in the Galilee (because people there would eat a lot of meat). Rabbi Yehuda said that the seller must inform the buyer in a case where he sold both animals on the same day but if they were sold on different days then he need not inform him. Nevertheless Rabbi Yehudah agrees that if one sells the mother to a groom and the calf to the his bride, he must inform them because it’s obvious that they‘ll both slaughtering on the same day.

Chulin 5:4

At these four times, a butcher can be compelled to slaughter against his will. Even if an ox is worth a 1,000 dinar and the one buying it has only one dinar (which he paid for his portion but no one else bought any shares in this animal), the butcher is compelled to slaughter it. Therefore, if the animal died before being slaughtered, the buyer loses his investment. This is not the case on other days of the year; on other days, the butcher is not compelled to slaughter and, if the animal dies, the seller incurs the loss.