1,014. An Animal Born on Yom Tov

Shvisas Yom Tov 1:24

The two days of yom tov observed in outside of Israel are considered two separate periods of holiness and not like a single day. Therefore, something that was muktzeh on the first day, or that came into existence on the first day, is permitted on the second day if designated for use. For example, an egg that was laid on the first day of yom tov may be eaten on the second day; animals that were trapped on the first day may be eaten on the second day; produce that had been attached to the ground on the first day but became separated may be eaten on the second day. Similarly, one may paint his eyes medicinally on the second day of yom tov even if his discomfort is not incapacitating. All this applies to the second day of yom tov observed outside of Israel; the two days of Rosh Hashana are considered a single period of holiness, like one day, in all matters except for burying the deceased (as discussed in halacha 1:23, above). An egg laid on the first day of Rosh Hashanah remains prohibited on the second day; the same is true in all similar situations. Whenever Shabbos follows yom tov, or vice versa, an egg laid on one is prohibited on the other; this is true in all similar circumstances. Even if an egg is laid on a second day of yom tov that is followed by Shabbos, it may not be eaten on Shabbos.

Shvisas Yom Tov 2:1

A chick that hatches on yom tov may not be handled on yom tov because it is muktzeh. If a calf is born on yom tov, then if its mother was designated for eating, the calf is also permitted. The calf is considered designated because it was in the mother, which was designated. If the mother had been slaughtered before the calf was born, the calf would have been permitted on yom tov even though it was not yet born.