Laboratory animals serve as the cornerstone in life science research, acting as surrogate models for human physiology, pathology, and disease treatment. They play an irreplaceable role in basic research, drug development, and translational medicine. Gut microbiota, a complex microbial community comprising bacteria, fungi, viruses, and unicellular organisms, colonizes the host's intestinal tract and is closely associated with the maintenance of normal physiological metabolism and overall health. Studies have shown that dysbiosis of the gut microbiota can lead to various diseases, including obesity, diabetes, hypertension, inflammatory bowel disease, and Alzheimer's disease. Therefore, conducting characteristic analyses of the gut microbial composition of laboratory animals can not only enhance the reliability of experimental outcomes but also facilitate their translational application. Sex differences represent a critical variable in biological research, significantly influencing the physiological functions, metabolic traits, and gut microbial composition of laboratory animals. However, a pronounced sex bias has been widely observed in many biological studies, thereby limiting the generalizability of results. This study focused on ten commonly used laboratory animals in life sciences, including mice, rats, guinea pigs, hamsters, rabbits, dogs, cats, non-human primates, miniature pigs, and chickens. Their gut microbial composition was summarized and related sex-specific differences of certain species were analyzed. Furthermore, by comparing the gut microbiota of laboratory animals with that of humans, this study offers novel perspectives for comparative medical research. In summary, this study not only deepens researchers' understanding of gut microbiota characteristics and sex-dependent variations across laboratory animal species but also provides practical guidance for selecting appropriate laboratory animals, constructing sex-specific disease models, and interpreting experimental results in scientific studies.

Laboratory animals serve as the cornerstone in life science research, acting as surrogate models for human physiology, pathology, and disease treatment. They play an irreplaceable role in basic research, drug development, and translational medicine. Gut microbiota, a complex microbial community comprising bacteria, fungi, viruses, and unicellular organisms, colonizes the host's intestinal tract and is closely associated with the maintenance of normal physiological metabolism and overall health. Studies have shown that dysbiosis of the gut microbiota can lead to various diseases, including obesity, diabetes, hypertension, inflammatory bowel disease, and Alzheimer's disease. Therefore, conducting characteristic analyses of the gut microbial composition of laboratory animals can not only enhance the reliability of experimental outcomes but also facilitate their translational application. Sex differences represent a critical variable in biological research, significantly influencing the physiological functions, metabolic traits, and gut microbial composition of laboratory animals. However, a pronounced sex bias has been widely observed in many biological studies, thereby limiting the generalizability of results. This study focused on ten commonly used laboratory animals in life sciences, including mice, rats, guinea pigs, hamsters, rabbits, dogs, cats, non-human primates, miniature pigs, and chickens. Their gut microbial composition was summarized and related sex-specific differences of certain species were analyzed. Furthermore, by comparing the gut microbiota of laboratory animals with that of humans, this study offers novel perspectives for comparative medical research. In summary, this study not only deepens researchers' understanding of gut microbiota characteristics and sex-dependent variations across laboratory animal species but also provides practical guidance for selecting appropriate laboratory animals, constructing sex-specific disease models, and interpreting experimental results in scientific studies.