Studies analyzing the composition of gut microbiota are quite common at present, mainly due to the rapid development of DNA sequencing technologies within the last decade. This is valid also for chickens and their gut microbiota. However, chickens represent a specific model for host-microbiota interactions since contact between parents and offspring has been completely interrupted in domesticated chickens. Nearly all studies describe microbiota of chicks from hatcheries and these chickens are considered as references and controls. In reality, such chickens represent an extreme experimental group since control chicks should be, by nature, hatched in nests in contact with the parent hen. Not properly realising this fact and utilising only 16S rRNA sequencing results means that many conclusions are of questionable biological relevance. The specifics of chicken-related gut microbiota are therefore stressed in this review together with current knowledge of the biological role of selected microbiota members. These microbiota members are then evaluated for their intended use as a form of next-generation probiotics.

Department of Immunology Veterinary Research Institute 621 00 Brno Czech Republic

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Contact with adult hens affects the composition of skin and respiratory tract microbiota in newly hatched chicks

Succession, Replacement, and Modification of Chicken Litter Microbiota

High resolution parallel sequencing reveals multistrain Campylobacter in broiler chicken flocks testing 'negative' by conventional culture methods: implications for control of Campylobacter infection

Host Species Adaptation of Obligate Gut Anaerobes Is Dependent on Their Environmental Survival

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Different Bacteroides Species Colonise Human and Chicken Intestinal Tract

Environmental Impact on Differential Composition of Gut Microbiota in Indoor Chickens in Commercial Production and Outdoor, Backyard Chickens