i have a 5 week old hen and 6, 3 week old isa browns. some suggest flock raiser but is that for meat birds or is it also for hens? what age should i feed it cause it says that at 10 weeks i should end chick starter/grower and move to something different. im a little over half a bag used so should i move to something else after i finish this bag. flock raiser is said for being from chicks to laying and once i get to laying i give them layer feed with oyster shell?