What is an acceptable food conversion ratio for broiler chickens?

Image by Compassion in World Farming
Broiler chickens on straw and straw bales inside with feeders and open pop holes in background. Free-range system.

Question by Mel: What is an acceptable food conversion ratio for broiler chickens?
i can’t find broiler chickens on their own, and due to the selective breeding involved in producing the broiler chickens, it may differ between broiler and layer chickens. Thanks heaps for your help.

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