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Background Gastrointestinal (GI) motility is a complex physiological process that is critical for normal GI function. Disruption of GI motility frequently occurs in GI diseases or as side effects of therapeutics. Whole gut transit measurements, like carmine red leading‐edge transit, in mice form the cornerstone of in vivo preclinical GI motility studies. Method We have developed an easily achievable, labor‐saving method to measure whole gut transit time in mice. This approach uses inexpensive, commercially available materials to monitor pellet production over time via high definition cameras capturing time‐lapse video for offline analysis. Key Result We describe the assembly of our automated gut transit setup and validate this approach by comparing the results with loperamide to delay transit and conventional transit measurements. We demonstrate that compared to the control group, the loperamide group had slowed transit, evidenced by a decrease in total pellet production and prolonged whole gut transit time. The control group had an extended transit time compared with the results reported in the literature. Whole gut transit rates accelerated to times comparable to the literature by disrupting cages every 10‐15 min to imitate the conventional approach, suggesting that disruption affects the assay and supports the use of an automated approach. Conclusion & Inferences A novel automated, inexpensive, and easily assembled whole gut transit setup is labor‐saving and allows minimal disruption to animal behavior compared with the conventional approach.

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The gastrointestinal tract is in a state of constant motion. These movements are tightly regulated by the presence of food and help digestion by mechanically breaking down and propelling gut content. Mechanical sensing in the gut is thought to be essential for regulating motility; however, the identity of the neuronal populations, the molecules involved, and the functional consequences of this sensation are unknown. Here, we show that humans lacking PIEZO2 exhibit impaired bowel sensation and motility. Piezo2 in mouse dorsal root but not nodose ganglia is required to sense gut content, and this activity slows down food transit rates in the stomach, small intestine, and colon. Indeed, Piezo2 is directly required to detect colon distension in vivo. Our study unveils the mechanosensory mechanisms that regulate the transit of luminal contents throughout the gut, which is a critical process to ensure proper digestion, nutrient absorption, and waste removal.