I,ve got 30 or so very healthy birds, all doing great even in the cold. I do not like to treat, but to prevent, naturally.. One of my leghorn hens has been acting 'blah' lately. Shes been inside for a few days now. She eats and poops, but thats about it, just seems like she feels like crap. I give her ACV, DE, garlic, olive oil, oats, honey, ect. All the natural good stuff. She has no symptoms of any illness. What gives?? Should I keep doing what I'm doing or do you think it would be better to cull???