Have you ever been perusing the egg selection at the grocery store and noticed labels professing that the eggs contained in the carton were laid by chickens that ate an "all vegetarian" diet? Granted, most of us here probably do not pay attention to the eggs in the grocery store as we are hopefully collecting enough of our own to sustain our families, but if you were to look, you might be surprised at what you will see.
Chickens, by nature, are not vegetarian, so it is hard to fathom why it is advantageous to feed them an all vegetarian diet. If you watch a chicken going about the business of being a chicken, you will see that animal constantly dig and scratch, looking for something to eat. Those desirable food items come in the form of worms, bugs, grubs, larvae, etc. Sometimes a chicken will even snack on a frog if the opportunity presents itself. If you've ever fed your chickens meal worms, you know how voraciously those are devoured. None of these delicious snacks fall into the category of vegetarian, so it seems like an obvious conclusion that if a chicken is fed only vegetarian items, there is some serious deprivation going on in that animal's diet. There are simply things every animal needs in its diet, and in the case of a chicken, protein is one of those things, especially during molting.
Since chickens are omnivores and need meat in their diets, the next logical step is to determine the types of meat that are acceptable. Obviously, naturally occurring meats such as bugs are good for your chickens. What is not good for chickens, or the people who later consume those chickens or their eggs, are some of the things fed in commercial settings. This can include plastic pellets (intended for roughage), same-species meat, rendered road kill, horses, and cats and dogs that have been euthanized. Cats and dogs that are euthanized are often done so through the use of sodium phenobarbital (which is obviously toxic since it is used to kill animals) or a carbon monoxide gas chamber. Also used in animal feed are rendered feathers, hair, skin, hooves, blood, and intestines, which are disguised by being label as "animal protein products." Would you want to eat an animal, or eggs from an animal, that was fed such a diet? Despite the obvious issues with a vegetarian diet, it almost seems like a better choice than this.
While our chickens were not intended to eat a vegetarian diet, it goes without saying that they were also not intended to eat dogs, cats, or the hooves and intestines of other animals. Store bought eggs and meat seem more and more like something to avoid, which is unfortunate because so many people depend on those items to feed their families. It is definitely time that we call such practices into question and demand that change at long last be made for the better. Until that change is able to take place, however, do your best to let your chickens free range and eat bugs to their hearts content for their comrades who cannot.