To make a breed show up / not show up in the AC

Quote via Nick Sherlock by email:

To make a breed not show in the adoption center:
Interesting! Yes, this is possible, although I don't know what use you'd have for it. In LNZ Pro, open your breed, edit the RCData section and change the tag from 1 to 9. You could also make the pig show up in the adoption centre by doing the reverse.
The tag is a combination of special options for your breed, a pig has:
1 + 8 + 16 = 25
A normal breed has:
1
The '8' option is the one that hides the breed from the adoption centre, so setting the breed's tag to:
1+ 8 = 9
Hides it. I don't know what the 16 option does, could be worth experimenting
Yes, it's 25 because it also includes the 16 option, I don't know what it toggles. You could change it to either 1 or 17 for it to appear in the adoption centre.
Yes, to make the great dane not show up, use 9.
The 16 option could well be what makes the pig show up neutered, perhaps this will be useful for hexers making crazy breeds which shouldn't mate.

Quote via Roxy on the petz forum

To confirm, having checked, the 16 option is what makes them show up neutered, but you aren't able to breed them even when un-neutered.