My baby is 2.5 months old. From early morning she has been passing loose stool. She did it for 6 times till now. The first one was greenish yellow. And gradually the colour kept changing. Now it's yellow with whitish stains. Attaching the pic. We changed her formula from aptamil gold to similac total comfort this Monday. As she was not able to drink milk due to gases. She is exclusively on formula. My paed advised to do the stool culture. Just wanted to confirm if it's required. Or it might be due to the change in formula.