What is this white thing that came from my guineas vag

[808guineas]

I have a herd of all girls
And today I was cutting nails when I saw this white thing sticking out of one of my girls private parts and we pulled it out and uhhhh idk what it is

 

[Soecara]

It is a mucus plug. They shed them when they go into heat, however you almost never will see them.