2019, December:

I give Sapphire pigz. Sapphire discovers that pigz eat bug barns. This should be impossible, as bug barns are explicitly marked as "inedible" objects in the game's code. (Source) (Source)

2019, December 23rd-26th:

The best four days of my life. It is discovered that pigz are, in fact, not dogz. Despite using dogz animations and body structures, they are treated by Oberon (a part of the game that handles object interactions) as a distinct species from dogz and catz. They have unique AI routines within the game's State Machine, and special code that overwrites typical behavioral code for petz. This includes being a special exception to "inedible" objects'... well, inedibility. They also have a unique toy interaction that causes them to process the "spray bottle" object's spritzes of water as a reward instead of a punishment - a totally unique behavior literally no other animals in the game possess.

The potential for modding new behaviors into Petz had been uncovered.

2022, June 9th:

Prism isolates and fixes the code responsible for pigz and bunniez being unable to breed, while researching the pig and bunny's potential for adding new animations to breeds.

For the first time, we have breedable pigz that are actually made directly from the original pig.dog breedfile.