We oredered 36 chicks and they arrived 3 days ago weak, from 3 days in the mail. They revived with warmth, food and water. I put TS Probiotic and Electrolytes in water, and behavior improved. Pasty butts on 10 yesterday, removed plugs. More pasty butts today. Will remove now. 2 have died, never really thrived. One more looks like it's on the way out. Is this to be expected? It's our 1st time with mailed chicks. We bought the 55 cents each ones, rather than the $2 each. How do I prevent them from dying?