What's wrong with gray swallows rare

The gray swallows are rare explaining that they have eaten unhygienic foods or have a cold.If you eat unhygienic foods, you need to clean up the things in the tank in time, and clean it regularly to keep the cage clean and tidy.It is best to check the feed to see if there is a deterioration.If you have a cold, you need to pay attention to keep warm to avoid cold wind blowing, and you should dry dry when you take a bath.