We have 50 baby chicks picked up from the mail on Friday. 20 are leghorns. They all did good for the first day and then last night we lost 7 leghorns. No idea why. They have an appropriate size pen with red bulb heat lamps on each end and food/water in the middle. They all appeared to be drinking water with electrolytes in it. The other breeds (orpington, Americana and RI reds are fine). Any suggestions on what we need to change to save the leghorns. They are my son's chicks and he is worried he will lose all the leghorns.