This is on PC. If it extends to other platforms, I don’t know.
The new variants for Cows, Chickens, and Pigs are not appearing on my Bedrock Realm.
All of the other biome changes are appearing but the farm animals are still showing as the originals.
When I created creative copy of the Realm, they still will not appear and even their spawn eggs (along with several others) do not show the updated designs.
In a brand new Creative World, everything is appearing as it should in 1.21.70.
This has been happening with my horses as well, even ones that have already been tamed and ones that haven’t taken damage. Currently, I have a group of 14 & 15 heart horses that I’m working on breeding and the heart counts have all dropped to anywhere from 13 down to 7 hearts.
[media][media](FYI: this is on Bedrock Realms on PC and is still happening as of the latest update)