Man has mastered all kinds of situations, and has grown to a very high degree of dietary versatility. Animals are not so "fortunate". They must have very precise types of food, at precise times. Some more than others, of course. Domesticated animals, living with man for the last several millennia, have adapted to man's diet to a far greater extent than wild animals.
Chickens are one of man's closest domesticated friends. They, like dogs, have grown to eat many of the foods of their keepers. But chickens cannot be assumed to just "make it" on any kind of stuff. They will probably "make it" on man's junk food, but they won't be as healthy as they could be, nor will they be much good as egg layers, unless they are fed the basics of what they need. And mold or salt in table scraps and old grains can quickly kill a chicken.
WHAT CHICKENS NEED (It's simple!)
1. Grains (whole, living grains are way better than cracked, and a mixture is way better than pure corn)
2. Greens (grass! weeds! fresh veggie parings from kitchen!)
3. Protein (in summer, they get enough bugs -- but in colder weather they need protein supplementation, including perhaps the following: yellow-jackets from restaurant traps, soybeans -- see below, worms, milk, meat --- but sea fish is the very best)
And WATER, WATER, WATER.
Chickens won't always search far for food or water. Sometimes they won't even go around a see-through fence to get it. And they need lots of water, especially when laying. We put the water dish right by the door of their coop, where they can get it every time they go by. They can die of salt toxicity in a few hours if not given water at all times. They will shun dirty water, so make a point to keep it fresh using the BAMN method (By Any Means Necessary).
If they're Fenceless Free Range, that's about it. But if you keep them penned up most or all of the time, even in a largish yard, you will also need to make sure they get . . .
4. Hard grit (do not confuse this with oyster shell or calcium --- these dissolve in the chicken's digestive system, grit does not --- grit is used in place of "teeth"); quartz-based sand with angular edges (not rounded, as often is found in riverbeds) can be collected wherever you find it.
5. Calcium (crushed oyster shell, other shells, ground or hammered bone) (There's lots of calcium in greens, if they get to forage all day.)
6. Vitamins A (and D if the weather is cloudy for long stretches)
7. Salt (best given separately, free choice; kelp is the very supreme choice for this, if you can get it --- it supplies all the minerals in the world --- see below)
If you're confining your chickens at all, even in a largish yard, and feeding them only one pre-mixed type of feed, you need to blend in the correct proportion of grains and protein. See the protein section for mixing grains and protein. (Contact our Feed Experts if in question, but not until reading the Protein section.)
If your birds are Fenceless Free Range, you don't need to mix the protein into the feed. Rather, let them have a special protein dish in the morning or afternoon. An ideal one, that will keep them laying all Winter, is soybeans, mixed with a little bit of instant oats, a few nuts, and milk for variety. Or, some fresh fish you have left over. They really love canned ~~ unsalted! ~~ fish, but it's usually too expensive for the usual fare. Unless you have a good source. There are all sorts of ways to make your chickens happy as well as healthy. And happy chickens aim to please; they are not so prone to bad habits. For some real fun, see the "Traditional Recipes" section for how supplementary feeding was done in the Old Days.
Also, we're really interested in getting into worms for protein! Another great, unused protein resource is the plethora of yellow jackets that are caught in traps near restaurants around the world. The attractant in those traps(1) is not a poison, it is just an odor; (2) is not consumed by the yellow jackets, and (3) is highly volatile anyway, meaning that any trace that might be on them will disappear after removing the (dead) yellow jackets from the trap. Chickens will instinctively avoid the dead yellow jackets at first, but their curiosity and good sense will quickly win out, and they'll gobble them up whenever they see you bringing them. Many restaurants will happily give you their yellow jackets. Or, offer to put up a trap for them yourself, at a restaurant that you see has a problem with yellow jackets. (In which case, study the directions for placing the trap thoroughly, to avoid causing a highway of yellow jackets that patrons might cross!)
Scratch grain mix, from feed store, containing many kinds of grain ($5/50 lb)
Extra yellow corn (cracked) --- it gives them warmth in the winter, we're told
GRAINS MUST NEVER BE WET AND MOLDY -- CAN KILL!
Kitchen trimmings (thrown in the compost pile near their coop)
PROTEIN (MAINLY SOYBEANS)
Every morning (quantity for 12 chickens): 3/4ths cup of boiled soybeans ~~ (make a batch every week or so: SOAK 2 cups of dried soybeans in three or four times the volume of water overnight; bring to ROLLING BOIL in the same soaking water for 15 minutes; DRAIN; STORE in fridge) mixed with 1 cup of instant oats, some sunflower seeds, milk to moisten, warmed up.
Every other afternoon, same thing, with some fish flakes, bits of scrap fish, or some canned cheap fish.
Crushed, is kept in their coop, $5 for 50 lbs
Dried kelp fronds (the leafy parts, not the stalks, which are too hard to chop up and don't get eaten) are kept in their coop on a sturdy clip. They can free-choose it, letting them adjust their salt and mineral intake. There are nearly 100 minerals on Earth. Only sea water and sea life has them in the ratios that animals need. All blood of animals contains these minerals, in the same proportions as in sea water! Scientists have barely scratched the surface of understanding all the things that these minerals do in living bodies. For optimum health, it's best to get all of them.
Just gather a mess of kelp off any beach that is more than 50 miles from a city, sling it into a garbage bag and take it home. At home, set it out in the yard, and in a very short while, it will be dry and crisp. Take the flakey parts, and clip them about a foot off the ground where your chickens frequently go --- those document clips with a black "hinge" and two folding silver "arms" work best.
Collect angular granite grit from trips to areas that have it. Tiny chicks need tiny grit, so get a variety of sizes. A little lasts a long time. The girls will pick and choose a few choice pieces now and then. Fun to watch them study and try out the different grains of grit.
See the "Family Poultry" feed instructions section for a published account of standard feeding practices for small flocks of chickens.