In the future when the Temple is rebuilt in Jerusalem will the Temple officials begin practicing the rituals and ceremonies as described in the Torah, most specifically including animal sacrifice?
The 613 commandments of the Torah are unchanging. The laws of the Temple service, including animal sacrifice, will therefore continue once the Temple is rebuilt. While the Medrash (VaYikra Rabah 27) teaches that in the future all sacrifices except for the Korban Todah will be discontinued, the Maharal (Tiferet Yisrael) teaches that statements of the rabbis referring to various mitzvot no longer being obligatory refer to the time of the resurrection of the dead and not to the world as we know it. For an explanation as to why the sacrifices should, from a moral perspective continue until that time, see Rav Kook Iggrot HaR'Iyah 140.