In American folklore, a chicken is synonymous with cowardice. This is not necessarily a fair assessment, but it is very common. Therefore, calling somebody a chicken equals questioning this person's bravery. It would have been really cool if feeding on black soldier fly larvae made chickens as brave as lions (except for chicken farmers because handling such brave chickens can be a challenge). However, a recent study of chickens fed on live black soldier fly larvae did not find any change in their fear behaviors. Their gut microbiota did change, though, but it is less exciting.

Huang, C., Hernandez, C.E., Wall, H., Tahamtani, F.M., Ivarsson, E. and Sun, L., 2024. Live black soldier fly (Hermetia illucens) larvae in feed for laying hens: Effects on hen gut microbiota and behavior. Poultry Science, 103429. https://doi.org/10.1016/j.psj.2024.103429

This study examined the effects of including live black soldier fly (BSF, Hermetia illucens) larvae in the diet of laying hens on gut microbiota, and the association between microbiota and fearfulness. A total of 40 Bovans White laying hens were individually housed and fed one of four dietary treatments that provided 0, 10, 20%, or ad libitum daily dietary portions of live BSF larvae for 12 weeks. Cecum microbiota was collected at the end of the experiment and sequenced. Behavioral fear responses to novel objects and open field tests on the same hens were compared against results from gut microbiota analyses. The results showed that the bacteria genera Enterococcus, Parabacteroides, and Ruminococcus torques group were positively associated with increased dietary portion of live larvae, while Lactobacillus, Faecalibacterium, Bifidobacterium, Subdoligranulum, and Butyricicoccus were negatively associated with larvae in the diet. Inclusion of larvae did not affect fear behavior, but the relative abundance of Lachnospiraceae CHKCI001 and Erysipelatoclostridium was associated with fear-related behaviors. Further studies are needed to determine whether the change in gut microbiota affects fearfulness in the long‐term.