Hey there! I'm happy to help!
After the Civil War ended, the U.S. was reunited shortly afterwards, so it would make no sense to swear allegiance to the union if the Union was about to merge with the South to be the U.S. again.
The requirement to free slaves came from the Emancipation Proclamation and the 13th amendment, not when the Confederates surrendered.
Why would they want the Confederates to surrender their livestock? The livestock aren't doing anything wrong and that's just plain mean because people needed livestock to live back then, so this one does not make sense.
Giving up their weapons make sense. They needed to be disarmed for a bit so they wouldn't start more conflict but they were allowed to return home shortly after. Therefore, this answer makes the most sense.
Under the surrender terms, the Confederates were required to give up their weapons.
Have a wonderful day! :D