Before slaughtering, the shoḥet recites: Barukh ata Adonai Eloheinu melekh ha-olam, asher kideshanu be-mitzvotav ve-tzivanu al ha-sheḥita (“Blessed are You, Lord our God, King of the universe, Who has sanctified us with His commandments and commanded us concerning sheḥita”). If he forgot to recite the berakha before slaughtering, it can no longer be said, but the sheḥita remains valid (SA YD 19:1).
When one intends to slaughter several animals, one berakha covers them all. From the berakha until the final slaughtering, he should not speak about unrelated matters; he may speak about matters connected to the sheḥita itself.
Even though an animal may later be found to be a tereifa, leaving its meat forbidden, the berakha is recited before slaughtering each animal because most animals are kosher. If, however, a question about the animal’s kosher status arose while it was still alive – for example, if it was sick or injured – the shoḥet should not recite the berakha before slaughtering it, since the sheḥita may not permit its meat. After the sheḥita, the animal should be examined promptly; if it is found to be kosher, the shoḥet recites the berakha immediately (Rema YD 19:1; Kaf Ha-ḥayim 8, 11). Better still, the animal whose status is uncertain should be slaughtered together with an ordinary animal or bird: the shoḥet recites the berakha before slaughtering the ordinary animal or bird, and that berakha covers the animal whose status is uncertain as well (Taz and Shakh).
