This is was happened:

i gained 180 O'Ghomoro Berries from 5 seeds i planted in my FC garden, wanted a Ink Blue chocobo, that's why so many berries, so I stabled it and started to feed him with 100 berries. Obviously after the first 3 berries it already started to say my chocobo was beginning to grow new feathers, and it kept repeating that for the last 97 berries. After 20 minutes i was done, left it in that stable and went to bed. Woke up 10 hours later and my chocobo was still there, happy, fat and yellow as a lemon. Started to worry about it and thought that maybe it needed more time because of all those berries... i left it there for 5 more hours, got back and it was still yellow... waited 4 more hours and that chicken was still yellow as a canary. So after 19 hours i took him out to see if maybe it would suddenly change out of the stable... and of course it didn't, its colour was still Desert Yellow.

I reported the bug in game and contacted the GM who told me to post the issue here.