Chickens are omnivorous birds that feed on a variety of items of both plant and animal origin. In the wild, insects constitute a significant part of their diet. In captivity, chickens are often limited to formulated feeds that rely on fish and soybean as sources of protein and fat. Including black soldier fly larvae restores a more natural order of things and diversifies their diet. Being omnivorous, however, chickens cannot simply switch to eating black soldier flies and little else. The goal of using black soldier fly larvae is to provide chickens with a well-balanced, nutritious food, not to force them to become insectivores.

There are two ways to feed black soldier fly larvae to chickens. One is to give them whole larvae, either alive or previously dried, as a treat in addition to their regular feed. In theory, canned larvae could be an option as well, but they are expensive and usually used for reptiles. Dried whole larvae can also be mixed with formulated feeds. Under such a scenario, black soldier flies do not provide a significant proportion of overall nutrients but enrich diets and make chickens happier. Chickens readily consume black soldier flies and show a positive response to their incorporation into their diets, both behaviorally and physiologically.

Another approach is to replace protein and oil derived from fish and/or soybean with protein and oil derived from black soldier fly larvae in formulated feeds. This replacement can be incomplete, with two or three ingredients mixed together. Existing scientific studies have shown that chickens perform at least as well, and often better, on the feeds containing black soldier fly ingredients compared to regular feeds. In addition to improved growth, such chickens may also have better gut health and improved immunity. However, these effects are not universal and depend on the amount of black soldier fly larvae in a feed, its ratio to other ingredients, and the diet of black soldier flies themselves. Excessive amounts of black soldier fly meal or oil may be detrimental both to chicken growth and health parameters, as well as to the quality of chicken meat. In particular, contents of saturated fat may go up at the expense of a much more beneficial polyunsaturated fat. Therefore, it is important to make sure that feed formulations are properly designed and tested before being fed to chickens on a regular basis.