Updated: Jul 23
A honeybee may seem too small to have one billion cells in its gut. But honeybees, like humans, have a uniquely specialized gut microbiome that has developed over millions of years of coevolution. It contains bacteria and fungi that take substances bees ingest and use them for good – to break down food into energy, release nutrients, dissolve toxins, and fight off infection. Likewise, there are viruses and parasites that take substances bees ingest for themselves, for example, Nosema parasites that leech iron from the bees.
A balanced gut microbiome helps optimize digestion and nutrition, and increases a bee’s ability to combat chalkbrood, fight off mites, support pesticide detoxification, and increase hive immunity. An unbalanced gut microbiome can lead to low weight, an intolerance for viruses, and vulnerability to pesticides.
The team at Strong Microbials sees the power of the bee gut microbiome firsthand. Throughout the year we care for bees in our rooftop apiary in Milwaukee, Wisconsin. And we collaborate with commercial, sideliner, and hobbyist beekeepers across the country to better understand bee health. Following are the ways the microbiome is the key to honeybee colony health and critical to bee survival.
1. One Billion Cells. According to a study released in 20152, the honeybee adult worker harbors a large bacterial community in the gut, with roughly 1 billion bacterial cells in mature workers. A study released in 20203 used metagenomic sequencing to find that there are also billions of viruses that attack the bacteria, and that 76% represent viruses that have never been seen before.
2. Extraction of Dietary Nutrients – Gut microbiomes of bees, like those of humans, digest food to separate and synthesize the vitamins and nutrients essential for life. Lactic acid bacteria (LAB) are abundant and important members of the honeybee gut microbiome. These bacteria provide multiple health benefits to honeybees: improved digestion, boost immunity and detoxifications systems.
3. Fending Off Pathogens - LAB stimulate the honeybee immune system which correlates to elevated levels of host defense antimicrobial peptides. Anti-microbial substances excreted by beneficial bacteria known as microbial metabolites, suppress disease pathogens such as Chalkbrood (caused by the fungus Ascophaera apis); European Foulbrood (EFB) pathogen (Melissococcus plutonius); American Foulbrood (AFB) (caused by spore forming Paenibacillus larvae ssp.); the microsporidian parasite Nosema ceranae and the widespread adult honeybee parasite Nosema apis.