1. Rebbi Yochanan gives a different reason for why an animal or bird-like fetus is considered a Halachic birth.
2. Rebbi Yanai gives a third reason for why animal and bird-like fetuses are considered a Halachic birth.
3. Rav Acha suggests that the Rabanan might agree that a few types of bird-like fetuses may have the status of a Halachic birth.
4. Rebbi Yirmeyah asked Rebbi Zeira an amusing question about animal-like fetuses in order to get him to laugh.
5. According to Rebbi Meir, it is unclear what the law would be in the case of a human-like fetus in an animal.
A BIT MORE
1. The circular pupil of the eye of an animal or a bird is similar to that of a person (as opposed to that of a fish and other creatures).
2. Their eyes are in the front of their face, as opposed to the eyes of fish and other creatures which are on the sides of their face. The Gemara explains that according to Rebbi Yanai's reasoning, Rebbi Meir maintains that only a bird-like fetus that looks like a bird whose eyes are in the front of its face (such as an owl) is considered a Halachic birth.
3. Rav Acha understands that when the Beraisa says that "with regard to birds it should be checked out," it is following the view of the Rabanan. The Rabanan understand that a bird-like fetus that looks like an owl or other type of bird that has cheek bones that are erect like those of humans (in contrast to birds that have cheek bones like those of an animal) is considered a Halachic birth.
4. He asked: If a man gave his friend money for Kidushin for the fetus in the womb of his friend's wife, and it ended up being an animal-like fetus, is the man allowed to marry the animal's sister?
5. Perhaps just as Rebbi Meir says that an animal-like fetus is considered human enough to be considered a Halachic birth since it is from a human mother, a human-like fetus in an animal should be considered permitted to be eaten since we follow the status of its mother.