• Four opinions about the identity of a כוי

In a Baraisa, various opinions are cited as to the identity of a כוי. The Tanna Kamma says is it איל הבר – the species known as the wild ram. Some say it is הבא מן התייש ומן הצבייה – the offspring which comes from a goat and a deer. Rebbe Yose says: כוי בריה בפני עצמה היא – a koy is an independent creature, ולא הכריעו בה חכמים אם מין חיה אם מין בהמה – and the Sages did not resolve whether it is a species of חיה or a species of בהמה. Rabban Shimon ben Gamliel says it is a species of בהמה, and the house of דושאי used to raise עדרים עדרים – many herds of them.

• Rebbe Oshaya: shechitah of kodashim is always considered שחיטה שאינה ראויה

The Mishnah presented numerous cases of animals and their offspring of קדשים or חולין which were shechted inside or outside the Mikdash. Rebbe Oshaya says the Mishnah disagrees with Rebbe Shimon, who holds שחיטה שאינה ראויה לא שמה שחיטה – a shechitah which is not fit (i.e., does not permit the animal for consumption) is not legally called “shechitah.” As such, he would hold that wherever the first shechitah was invalid (e.g., kodashim outside the Mikdash), it would be permitted to shecht its offspring that day, since the parent was not considered “shechted.” The Mishnah taught that if an animal and its offspring are both kodashim, and he shechted both inside the Mikdash, the first is valid, and the second incurs malkus (for אותו ואת בנו), and is invalid (since it could not yet be sacrificed). But according to Rebbe Shimon, shechting kodashim is always a "שחיטה שאינה ראויה היא", because דכמה דלא זריק דם לא מישתרי בשר – as long as they did not throw the blood, the meat is not permitted in consumption. Thus, the second shechitah would not incur malkus, and would be valid. Although kodashim always requires shechitah (and if one tears open an animal and throws its blood on the מזבח, it is invalid), it is still considered שחיטה שאינה ראויה.

• Machlokes if one gets malkus for shechting "מחוסר זמן" in a case of אותו ואת בנו

The Gemara asks why our Mishnah did not mention that one who shechts an animal and its offspring of kodashim in the Mikdash also should receive malkus for sacrificing מחוסר זמן – a premature korban, since the korban could not be offered until the next day!? This is based on a Baraisa, which darshens to include כל הפסולין שבשור ושבשה  – all disqualified [korbanos] among cattle, and among sheep or goats, שהוא בלא ירצה – that [one who offers them] is subject to the prohibition of “it shall not be acceptable” (as a korban). The Gemara first answers that although he actually does incur malkus for מחוסר זמן, our Mishnah is not listing לאוי נוכראי – peripheral transgressions. Alternatively, Rebbe Zeira answers that one does not receive malkus for shechting a מחוסר זמן, because הכתוב נתקו לעשה – the passuk remedied it with a positive commandment: the passuk says מיום השמיני והלאה ירצה – from the eighth day (after an animal’s birth) it is acceptable (as a korban); this עשה to offer the korban in the proper time comes after the לאו prohibiting offering it early.