For the Passover what animal did they sacrifice?

Lambs were slaughtered at the original event in Egypt. By slaughtering the lambs, painting their blood on doorways, and then roasting and eating the meat, the Jews were physically displaying their rejection of the Egyptian false gods and their willingness to follow HaShem (The Creator).

Once established in Israel with the Temple, there were two animals that were sacrificed for Passover. Each family would slaughter a lamb as an offering of thanks to HaShem, the meat would then be roasted and eaten. A goat would also be slaughtered at the Temple as an offering of atonement for the Nation for any mistakes the Nation made as a whole community in the previous year.