Went on vacation and my neighbor and his wife chicken sat my girls. They did an excellant job except for one thing; they combined my Purina Start & Grow with my Purina Layena. I know that the calcium is bad for newer chicks because of the damage it can cause to their kidneys. The question I have is since my big girls are 32 weeks old and my chicks are 14 weeks old can the combination of these two feeds be dangerous to the chicks? My neighbors said they mixed both half bags really good and I can't tell because both feeds are the crumble type. So far my layers are still laying good eggs and their shells have not changed in thickness. My origonal plans were to use Purina Flock Raiser with oyster shell backup once my two half bags of different feeds were gone (until the chicks were 18 weeks old) and then go back to Purina Layena for all. Are the chicks in any danager, what must I do? I believe the combined feed will last until the chicks turn at least 18 weeks old. Any help would greatly be appreciated. Thanks in advance.