Reseachers are applying and testing the effects of alternative plant and insect based proteins to feed fish. These have different effects on the fish gut microbiome, and ultimately their health.
Gut microbiome populations exist in almost everything we consume, from fish and red meat to honey. Social bees collect microbes like Bifidobacterium from feeding on fermenting honey, according to an April 14 2020 study by University of Washington candidate Lila Westreich (2). She wrote about this in The Conversation. Westreich found that social bees collect microbes like Bifidobacterium from feeding on fermenting honey, according to the article (2). Research published in Plos One found 13 lactic acid bacteria that inoculate and preserve pollen in the hives. These include Lactobacillus kunkeei, and Alpha 2.2 (Acetobacteraceae), found in stored pollen and honey (3).
1 https://phys.org/news/2020-05-healthy-gut-microbiomes-farmed-fish.html ;
2 https://theconversation.com/amp/bees-seeking-bacteria-how-bees-find-their-microbiome-129534 ; and