What is the ruling on mixing the meat of sacrificial animals if 100 people share in 15 bovine sacrifices, and they are slaughtered and their meat divided in a way that makes it difficult to distinguish the meat of each cow from the others due to the crowding, knowing that the cows are of the same type and their weights are similar, and before mixing, permission is sought from those offering the sacrifice? And does this fall under the category of usury (riba) as mentioned in one of the books of Fiqh?

First: If the butcher slaughters someone's Udhiyah (definition) for a different group of people by mistake, it does not matter. That person's Udhiyah may suffice if it was performed at the correct time.

Second: Mixing the meats of the sacrificial animals leads to a problem, as some jurists consider it a sale of the Udhiyah meat, which is impermissible. However, the more authoritative opinion is that the mixing of Udhiyah meats is sufficient, and it is permissible to distribute them among the participants even if one person takes the meat of another's Udhiyah. This is because the division here is not considered a sale; rather, it is a "segregation" of each person's right from their companion's right, and this is permissible. The fundamental principle is that division is a distinguishing of a partner's right and not a sale. Therefore, it is permissible to divide mixed Udhiyah and sacrificial gift meats, even if selling them is forbidden.

Accordingly, the butcher should distinguish the sacrificial animals as much as possible, but if they become mixed, he should strive to distribute them. There is no harm in eating the distributed meat even if the Udhiyah meats were mixed, because this is not a sale.