Just like today, people did different things. Part of that depended on why you had chickens. Part of that depended on where you were, rural or urban, and your climate.
You had commercial operations where people provided eggs or meat to the market, but that was generally fairly small-scale and local. The big limiting factor was lack of refrigeration, especially lack of refrigerated trucks. Some people bought practically everything these chickens ate or raised a good part of it. I remember seeing an advertisement on here dated from the 1930’s or 40’s, I think it was Imp that posted it, where someone was selling a strain of Delaware chicks that could reach 4 pounds at 10 weeks, but that would require a high-protein diet. They could not do that free ranging and foraging for all their food.
I can’t speak too much on chickens kept in an urban area because I don’t have that experience, I grew up in the country many decades ago. I saw some small flocks in small town yards and envision them foraging for some of their food, being fed table scraps, and probably getting some supplemental feed. But I did not live that.
I grew up on a small farm in Appalachia that was a few miles from not much. I’m sure we raised our chickens the same way people had been doing it for thousands of years on small farms. Our chickens totally free ranged. During warm weather months our chickens and beef cows found their own food. We did not feed them a thing. The kitchen scraps went in the slop bucket and were fed to the pigs. The milk cow and the plow horses did get some corn we raised ourselves throughout the year in addition to what they foraged.
During the winter when the grass was not growing, the cows and horses were fed hay we grew ourselves. The chickens got some shelled corn we raised ourselves but not a lot unless there was snow on the ground. They still could find a lot of forage even in winter. The chickens did scratch around in the cow and horse manure. They got a lot of good partially digested nutrients from that. They also could pick through the areas where we fed hay to get some grass seed (grain).
We probably had around 25 to 30 hens and one or two roosters. They fed a family of seven plenty of eggs most of the year. We always kept some pullets so we even got some eggs in the winter, but yes the productivity dropped. During the summer we’d take excess eggs to the grocery store and trade those for flour or coffee, things we didn’t raise ourselves.
The hens hatched the eggs and raised the chicks. We ate practically all the roosters and the hens as they got older to make room for the pullets. We didn’t just limit the butchering to the roosters. That would be a waste.
We did not have a breed of chickens, they were a pure barnyard mix. It's what I think of as a heritage chicken, not a heritage breed but a heritage chicken. They are different. Every 5 or 6 years Dad would get a dozen chick at the coop, I remember New Hampshire and Dominique, whatever was available, and save one of the roosters and a few pullets to bring in new blood and keep the genetic diversity up. Those chicks were raised in a cardboard box on the back porch with a 60 watt incandescent bulb. They were fed nothing but cornmeal, ground from the corn we raised. Around 3 weeks of age, Dad would release them at the hen house. They were on their own after that. This was during late spring-early summer so it was warm, but they handled their own integration and found their own food and water. They made it on their own.
This is just one model. I’m sure there were many others. We bought practically nothing for our chickens, food or equipment, just those dozen chicks every few years. What little we fed them, and it was very little because of our climate, we raised ourselves. How efficient can you get, eggs and meat for practically no cost?
