As mention above, Layer Pellets/Crumbles/feed has "extra" calcium in it which may/can cause liver/kidney problems in chicks and Roosters.
The extra calcium and DECREASED protein... can also stunt growth and delay development including onset of lay. Feathers are made from 90% protein and it's amino acids. Young birds will go through several mini molts on their way to adulthood. Switch to layer now and watch your Silkies suffer from wry neck or worse... pretty much guaranteed. The foundation to any healthy flock after genetics is nutrition.
I never ever switch to layer... and dual purpose breeds like JG will do best with not less than 18% protein... Such as Purina flock raiser.
Chicks getting to the side dish of oyster shell is NO big deal... they may sample it but it won't be in every bite of feed they take and can't avoid the excess calcium as it would if it were "layer".
Please note that ALL feeds are basically the same regardless of what the company calls it. A bunch of confusing marketing terms, BUT appropriate age range is always listed on the bag. The MAIN difference is always protein and calcium levels, which are the most important factors. After that they have slight differences in amino acids and vitamin/mineral profiles... but all are formulated to meet a minimum guideline according to law... for the species and age range listed on the bags.
If you do decide to switch to "layer" feed, usually not before 16 weeks old for early maturing birds. Expect later than that for JG and Silkies. I start putting oyster shell out when I see the first egg. Which is actually always for my current flock that includes broody's, layers, roosters, chicks, juveniles, and so on.
Hope this helps.
Lucky #13... must see pics!
