This review aims to summarize data on avian microbiota, its development, composition, effect, and factors that affect its diversity in the chicken gastrointestinal tract (GIT) to be available for students, practical poultry specialist, and researchers in the poultry industry. The GIT of chickens like other animals and human are harboring a diverse population or community of microorganisms, including bacteria (microbiota), fungi (mycobiota), protozoa, and viruses are in symbiotic to enhance vital activities and the health of birds. . On the other hand, a bird's cecum microbiota has a high complex composition and fewer characteristic features than crop and all intestinal parts.
Microbiota starts to develop after hatching and gradually increased with age until the population reaches its balance. It can be affected by litter type, ration, as well as feed additives. The composition of poultry GIT microbiome was mainly investigated using microbiological culturing, while, molecular-based techniques provided more rapid and accurate characterization of the culture-able and un-culture-able members. The identification of intestinal microbiota helps in improving chickens' health and productivity programs.
Therefore, GIT microbiota and mycobiota should be carefully investigated for meat, litter, aerosol, and processing plant contamination to ensure both food and personnel safety.