This is an open bug that was archived. I am not sure if a new bug report is meant to be made.
Animal aging is turned off in options. Aging is turned off for all sims.
I have a save file I have p...
Ideas
I am using the mod from LittleMsSim it stop the aging but once I got back from U when I turn back on the aging my chickens and cow didn't age up I think the mod only disables the aging but doesn't interact with the game settings. Once I remove the mod my animals start aging again. For now I just use the mod until EA fix the issue only inconvenience is you have to put the mod in to stop the aging and take it off to to turn on the aging back