chicks not growing after 5 months... rather growing but very slow cochins and polish

[mustafa]

hello everybody i have abt 20 cochins and 15 polish, this is the first time i bought chicks day old,for the first 2 months i have kept them in a very small brooder as i couldnt leave them in the garden because of the predators, then a big cage for another 2 months... and for a month the chicks are now free range in an acre of grass all day long, they are 5 months old now, the cochins are an inch bigger than my bantams a bit overweight but very very active/ eating all the time and the polish are also half of adults... is this normal??? will they grow to be full size and huge like cochins are or because i kept them in a tight place when they were young they will never grow now....
awaiting replies eagerly... a hobbyist from Pakistan
bantams are full adults 1 year plus...

 

[smores]

Looks normal size to me, let them grow. My Cochins were very small and could fit n the palm of my hand

 

[mustafa]

at how many months were your chicken adult size?

 

[smores]

The were 8 months old.

 

[BravewingTheHen]

Don't worry; Cochins are known to be very slow growers. I have a Gold Laced Cochin right now, she is about 4 months old and is about the same size as your Cochin in the picture. Just be patient and before you know it they will be gigantic puff-balls.