If a firstborn animal (which is sanctified) fell into a pit on yom tov, Rabbi Yehuda says that an expert should go down and inspect it. If the animal is found to have a blemish (which disqualifies it), one may bring it up and slaughter it (since it may now be eaten), otherwise one may not. Rabbi Shimon says that if an animal’s blemish was not identified before tom tov, it is not considered prepared for yom tov use.
If an animal dies on yom tov, it may not be moved from its spot. Rabbi Tarfon was once asked about this and about challah that was rendered ritually unclean on yom tov. He went to the study hall and inquired. He was told that these things may not be moved.