Black soldier fly larva as a feed ingredient
Evaluation of dried black soldier fly larva as a feed ingredient for poultry production
Research identified changes in production and processing that improved the quality and suitability of dried black soldier fly larva for poultry diets, and indicated that the dietary inclusion of black soldier fly larva in broiler diets spared the utilization of corn and soybean meal without compromising growth and feed efficiency.
Black soldier flies have a worldwide distribution that includes the United States, but they are most abundant in the equatorial tropics. Female black soldier flies deposit their eggs near decaying organic matter such as animal manure, vegetative waste, carrion, and municipal waste. Once the eggs hatch the larva voraciously consume the organic material for about 18 days, and thus effectively convert this waste material into larval protein and fat deposits which sustain them through the pupa stage (14 day duration) and the adult fly stage (9 day duration). Nutrient dense larva can be harvested, dried and included in diets to support animal production. Given the rapid increase in the human population over the next 50 years, global food demand will increase by 100% which is greater than the projected increase in human food production. This will lead to shortages in cereal grains and soybeans, and greater levels of human malnutrition. Thus, finding alternative feed ingredients to reduce the dependence of animal agriculture systems on cereal grains and soybean meal while increasing food animal production is imperative. In addition, in many parts of the world such as Africa the development of poultry production is limited by the lack of nutrient dense locally produced feed ingredients and the dependence on costly imported feed ingredients. Black soldier fly larva has been used very successfully in aquaculture. However, its use in poultry production has been limited due to a lack of research and governmental approval of it as a feed ingredient for poultry. In September of this year, the U.S. Food and Drug Administration recommended the expansion of the dried black soldier fly ingredient listing to include feeding it to poultry. The goal of the present research was to 1) establish the nitrogen corrected true metabolizable energy value and digestible amino acid values of dried black soldier fly larva as these values are essential for formulating diets that meet the nutrient requirements of poultry, 2) identify potential production and processing practices to improve the suitability of this ingredient for poultry diets, and 3) prove that black soldier fly larva could be incorporated in broiler diets to replace part of the dietary corn and soybean meal without compromising animal growth and feed efficiency.
Cecectomized and intact adult Single Comb White Leghorn roosters were used in bioassays to determine the amino acid digestibility and nitrogen corrected true metabolizable energy content, respectively of black soldier fly larva from 6 different producers. Black soldier fly larva from 2 different sources was incorporated into broiler starter diets at 0 (control), 6 or 12% and fed from 0 to 21 days of age.
The current research indicates that the crude protein and fat content of black soldier fly larva is variable based in part on the organic substrate that the larva consumes, but primarily based on the age of the larva when they are harvested. During the larval stage crude protein content decreases by about 40% and crude fat increases by around 500%. In commercial production, black soldier fly larva are typically harvested near the end of the larval stage and this high fat product yields a true metabolizable energy value that is so high (1.42 times higher than corn) that it severely limits the incorporation of this ingredient in poultry diets. However, if the larva are harvested about 4 days earlier, the true metabolizable energy content is more similar to corn and black soldier fly larva can easily be incorporated into poultry diets. Initially, the digestibility coefficients of the amino acids of black soldier fly larva were 10 to 15% lower in 2 of the 6 samples tested. However, based on these results, these 2 producers were advised to lower the temperature utilized to dry the larva, and this eliminated the reduced digestibility coefficients of their dried black soldier fly larva. The amino acid digestibility coefficients of black soldier fly larva are equivalent or better than corn and soybean meal. Broilers fed starter diets containing 6 or 12% black soldier fly larva had body weight gains that were equivalent to those fed a control diet containing no black soldier fly larva. Overall, the results indicate that as commercial production practices are altered to increase the suitability of black soldier fly larva as an ingredient for poultry diets, it will have tremendous potential to decrease the reliance on cereal grains and soybean meal in poultry production. In addition, because black soldier fly larva can convert organic waste into high quality nutrient stores, this allows production of black soldier fly larva to be worldwide, and for dried black soldier fly larva to be paired with less nutrient dense locally produced feed ingredients to support the expansion of poultry production in areas of the world where cost effective feed availability inhibits poultry production.