Effects of Dysbiosis and Dietary Manipulation on the Digestive Microbiota of a Detritivorous Arthropod

Abstract

The crucial role of microbes in the evolution, development, health, and ecological interactions of multicellular organisms is now widely recognized in the holobiont concept. However, the structure and stability of microbiota are highly dependent on abiotic and biotic factors, especially in the gut, which can be colonized by transient bacteria depending on the host’s diet. We studied these impacts by manipulating the digestive microbiota of the detritivore Armadillidium vulgare and analyzing the consequences on its structure and function. Hosts were exposed to initial starvation and then were fed diets that varied the different components of lignocellulose. A total of 72 digestive microbiota were analyzed according to the type of the diet (standard or enriched in cellulose, lignin, or hemicellulose) and the period following dysbiosis. The results showed that microbiota from the hepatopancreas were very stable and resilient, while the most diverse and labile over time were found in the hindgut. Dysbiosis and selective diets may have affected the host fitness by altering the structure of the microbiota and its predicted functions. Overall, these modifications can therefore have effects not only on the holobiont, but also on the “eco-holobiont” conceptualization of macroorganisms.

Impact of intraspecific variation in insect microbiomes on host phenotype and evolution

“…Microbiomes change when arthropods encounter new or restrictive environments. Population size bottlenecks, common in conservation efforts, and biocontrol programmes, can result in loss of microbiome diversity [ 125 ], and consequently in reduced host fitness [ 126 ]. Captive rearing alone can result in loss or gain of harmless and beneficial microbes that then cause reductions in host fitness on the return of host populations to the wild [ 96 , 127 ].…”