Spawning in animals and breeding isn't working

[Darksong]

So as the title suggests, I spawned in animals. I did this way back when the trader update made us go into a new world cuz of a little change, so I did but I was very fond of my build so I decided to copy it with creative and plop it into my new world so I can continue playing with it and get all the new updates.

Now the issue is, my animals didn't carry over, only the eggs survived the transfer, this might be an error on my end but oh well. So with creative mode I spawned back the amount I had, set their generation to what it was and now they don't breed. They eat and it says they're ready to breed but they never do it, I've had a good amount of gameplay afterwards and the only ones reproducing are the new chicks that hatched from the eggs with a fresh rooster I brought in.

Is there an issue with spawned animals not breeding because they technically aren't wild animals with a pack? something in the code that's missing, or have I just done something wrong?

[Darksong]

Well, who would've guessed that going away for about an in-game week on an expedition and coming back will fix them. Case closed, they're pregnant.

[Evilel]

glad that you wondering off for an in-game week worked. normally I just roam far enough away that the game de-renders them and come back and it fixes the no impregnating issues

[Darksong]

Ah, so that's really all I needed to do, go far enough they de-render?
I was mostly making improvements in my base, harvesting, making wine and beer and taking care of smithing, so I was homebound for a long while.