Apparently Greek and Roman authors referred to weasels living in houses, which some people have taken to mean that they were either kept as pets or at least kept deliberately to keep down rats and mice: but they may just have been considered as pests themselves. https://foundinantiquity.com/2013/10/28/the-weasel-in-antiquity-pet-or-pest/
I couldn't help but think of Da Vinci...
That doesn't matter. The word "mustela" is feminine gender, and it's used to refer to any weasel of either sex; "mustela mea" is not necessarily a female weasel. Some animals do have a separate masculine and feminine word, but for the most part animals names have a single name with a particular gender, and that word is used regardless of the animal's actual sex.