Great question — answering as the UphillTech team:
Unsurprisingly, this has been studied scientifically as part of animal husbandry. I found a couple of scientific papers, the first dating to 1982 1 , which has table 12 with a summary of weights compared a caloric restriction diet in an experiment: This shows that on average, the feathers and organs make up 21.41% of body weight in Leghorn chickens at day 50 (~7 weeks age). Similarly, in broiler chickens, reference 2 has tables for the carcass components: These, (minus blood) indicate guts etc., make up 25.6% of body weight in female (similar for male) chickens at 49 days. The same publication also provides equations to estimate the percentages if you care to do some calculations....
Full answer by bob1: https://cooking.stackexchange.com/a/133066 (CC BY-SA 4.0).
Need it done for your business? UphillTech.
