What are you "free feeding" them? Are they in a coop & run? A tractor on grass that's moved daily? In a "wheelie coop" (or another type?) that they are let into pasture w/ poultry netting? Free range on pasture? In your backyard? What outside sources of feed do they have? Do you have a garden?
How to add weight between now & September?
Could be as simple as putting them out where they can graze - get different vitamin/minerals they may have missed when 1st hatched & nutritionally deprived. Grasses, weeds, flowers/herbs & bugs.
Can you get extra scraps/produce from a local restaurant, deli, coffee shop, grocery store or food pantry (even donated foods can "go bad" for consumption & is thrown out)?
Get seeds - alfalfa, boss, oats, barley, wheat, green peas (cheapest - bagged peas & lentils from grocery store). Start w/ 1-2 cups in a bucket - straight or mixed. Add enough hot water to cover them & let soak over night. Drain that water (offer to chickens, use in compost or water garden). Soak again in hot water. Maybe a 3rd day. Once sprouted, feed them to your birds. If you find it takes 3 days to sprout - use 3 buckets. After that 1st feeding, you'll find that you can feed sprouted seed every day. This is not replacing regular feed, it is a supplement ESPECIALLY if they are confined to a coop & run. You could also do fodder but even the least expensive set up can be pricey. I had issues w/ mold. Found just 2-3 day sprouting worked better for me.
Sometimes fermenting the feed you are using is good. I don't know much about that. Lots of info here on BYC.
How many cockerels vs how many pullets? Have you actually weighed them? The Orps may weigh less than the Aussies but look bigger. They have looser/softer feathers. It's really surprising!
The weight you gave, since they were malnourished & sick, sounds about right, though.
Were the 3 breeds you got from them bred from their own stock or did they purchase & grow out hatchery stock? If bred, did you see the parent stock - if so how big are they?
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I've asked a lot of questions!!
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Usually a HUGE difference in both Australorps & Orpingtons (ive only had a handful of JG/Ameraucana crosses & they were demolished 2 days before a planned butcher date - dogs jumped our farm fence. Not familiar w/ purebreds - other than being told they can take up to 9-12 months to develop the meat to match their frame) from hatcheries vs a breeding program that the breeder is aiming for meat.
A breeder has to consistently upgrade their breeding stock in order to maintain weights for meat. Tracking their weight vs age is helpful. Sometimes changing feeds. A lot of dual purpose breeds do better on a grazing/pasture or free range system, but not nessarily all.
I know that my own birds were closer to 20 weeks old & some were no- where near 8# (would be around 3-4# processed - maybe). Some actually weighed out @ 10-12 #s, but they WERE NOT fleshed out. They had long, thick legs, big boned frames & not a lot of meat. Those were crosses of Ameraucana/Brahma. Beautiful birds, but not meat birds.
Even other Heritage bred, dual purpose breeder produced birds do not have the same type of fleshed out meat as Cornish cross, and now the multitudes of other meat bird hybrids... The other hybrids often take quite a bit longer then cornish cross to be 5# birds, too.
. Ok I'll try that. Thanks!
. I want expecting monster birds but i had to do something!
