I started breeding rats two weeks ago I have 5 so far 2 males and three females. They are in 29 gal long tanks till my rack is complete. I keep a fan going in the room for air circulation. The room temp stays between 75 and 85 degrees. They get their bedding changed every three days and fresh water every day. I have noticed that two of my rats a male in the breeding tank and a prego female in my birth tank have started to sneeze every now and then. They have never been in contact with one another I bought the female as a pregnant one. Their coats are nice and shiny and soft, no nasal discharge could this just be them sneezing from the substrate or could I have respiratory infections starting???