Diversity of symbiotic bacteria in the digestive and circulatory systems of lobster and crayfish: important connections for efficient aquaculture. A systematic review

Lobsters and crayfishes have social, economic and ecological significance in several regions around the world. These crustaceans have complex digestive systems and open circulatory systems colonized by symbiotic microorganisms that play essential roles in the health, nutrition and disease of crustaceans, attracting considerable interest. The importance of the microbiota for the successful cultivation of animals in captivity is known, however, there is a lack of information about the symbiotic microbiota in different species of lobsters. The aim of this study was to summarize global information on microbiota studies of anatomical sites of lobsters and crayfishes looking for patterns of bacteria that colonize their intestine, hepatopancreas and haemolymph. A systematic review was conducted using “Methodi Ordinatio”. Twenty-five significant articles, from 12 countries, were identified for analysis from the Scopus database. The crustacean genera found were Cherax, Pacifastacus and Procambarus (crayfish); Homarus, Nephrops and Panulirus (lobsters). The intestinal, hepatopancreas and haemolymph microbiota show a wide variety of bacteria influenced by infections affecting the individual, stress caused by changes in the environment, availability and quality of food, period of the year, stage of development and the animal’s sex, among other aspects. The common core bacterial microbiota among crustaceans consist of the genera Acinetobacter, Aeromonas, Candidatus Bacilloplasma, Candidatus Hepatoplasma, Citrobacter, Hafnia, Photobacterium, Pseudomonas, Shewanella and Vibrio. The results broadened our understanding of the microbiota in the intestinal and circulatory systems of crustaceans, the flaws for and needs for standardization of analysis techniques, and the use of a multi-specialized approach for the protection and management of lobsters as a fisheries resource.