Raising the Knife and Guarding the Blood of the Bull

Rav Yehudah said in the name of Shmuel: the slaughterer must raise the knife upward, as it is said, "And he shall take of the blood of the bull" — and not of the blood of the bull together with something else. And with what does he wipe the blood of the knife? Abaye said, on the rim of the basin, as it is written, "basins of gold" (Ezra 1:10). Rav Chisda said in the name of Rav Yirmiyah bar Abba: the slaughterer must let the veins drip into the vessel. Rabbi Zeira said: one who notches the ear of the bull and afterward receives its blood — it is invalid, as it is said, "And he shall take of the blood of the bull" — a bull that was already whole. We have found this for the most holy offerings; how do we know it for the offerings of lesser sanctity? Rava said, it is taught, "an unblemished lamb" (written at remez 195).