Hi there..
Starter, grower, flock raiser, layer... all confusing terms... the real basic difference in ANY of them is going to be protein and calcium levels... organic or not is a personal choice that has zero baring on growth rate.
Some differences are simply genetic even with the same parents.
They may be using a different lighting system... some people keep lights on all night... I use natural cycles with true darkness. Ultimately, regardless of when different birds have their growth spurts or how fast they are growing they will still reach their maximum genetic potential once all is said and done. The only time extreme growth is is a plus is if you are processing for the table at a young age.
I personally NEVER go below 20% protein at any stage.
Some feeds will be medicated or not... if your birds experienced any bout with coccidiosis this could stunt their growth... if your birds are less confined they may be more active and SEEM more gangly than theirs...
Providing grit... has been proven to help the gizzard develop better which would maybe give better digestive uptake.
If organic is important to you then go for it.
One final word... It stinks that there is no industry standard for protein percentages in lets say starter... some starters are 22% while others like what the mana pro is only 18%... I would NOT feed my hatchlings 18%... While calories can only come from protein, fat, and carbs including fiber... and protein and carbs have the same amount of calories... Feathers are made from 90% protein and it's amino acids... and it takes protein to build muscle... I choose higher protein feed... and that is my suggestion for you... choose something with more protein..
That one says 19.5% protein...
https://www.tractorsupply.com/tsc/product/natures-best-organic-chick-starter-grower?cm_vc=-10005
How much has yours been?
Hope this helps.
