A systematic mapping review of cattle welfare research during road transportation (2015-2025)

This systematic mapping review aimed to characterize research trends, aggregate existing evidence, and highlight knowledge gaps in studies evaluating the impact of road transportation-related factors on cattle welfare outcomes. Four databases (Agricola, CAB Abstracts, Medline, Web of Science) were searched, and 125 peer-reviewed studies were included in the final analysis after a rigorous screening process. Data were extracted and synthesized using systematic review software and visualized using evidence gap maps. The review revealed studies were conducted across all regions of the globe, although Africa and Oceania had minimal representation (n = 8, 6.4% and n = 6, 4.8%, respectively). Transport duration or distance was the most studied transportation factor across the literature, included in 46.4% (n = 58) of the studies. Other factors commonly associated with transport stress, such as the external environment during transportation and the trailer stocking density, were minimally represented in the data (n = 15, 12.0% and n = 16, 12.8%, respectively). Studies included a wide range of cattle types, including a variety of stages of production (calf vs adult), sex classes (steer vs bull vs cow), and breed types (dairy vs beef). Research included multiple types of outcomes with physiological parameters measured in over half of the studies (n = 70, 56.0%). The characterization of transportation research across regions highlights the global differences in cattle production systems, infrastructure, and regulatory frameworks. This systematic map provides a valuable resource for researchers and stakeholders, identifying key areas for future research, and contributing to efforts to identify best management practices for transportation to improve cattle welfare.