2,303. Eggs of Unknown Origin
Maachalos Assuros 3:17
If a Jew sits near a non-Jew’s herd and the non-Jew gives him some milk from the herd, he may drink it even if the herd includes some non-kosher animals. This is so even if he didn’t see the owner milk the animal so long as he could have seen him had he stood up. This is because the non-Jewish owner wouldn’t dare to milk the non-kosher animal out of concern that the Jew might stand up and see him.
Maachalos Assuros 3:18
If both ends of an egg are round, or both are pointed, or if the yolk is on the outside and the white is on the inside, then the egg is definitely from a non-kosher species. If one end is pointed, the other is round, and the white is on the outside and the yolk inside, then it might be from a non-kosher species or it might be from a kosher species. Therefore, the Jew must ask the Jewish hunter who sells these eggs; if he says that they’re the eggs of a certain bird and this bird is kosher, he can be trusted. However, if he says they’re from a kosher bird but doesn’t define it by name, then he may not be trusted.