Abstract:Abstract: This study was designed to explore the potential benefits of alginate oligosaccharides as a feed additive in large-scale broiler farming. Despite the fact that alginate oligosaccharides have been confirmed to possess immunomodulatory functions, there is currently a dearth of research on their direct application in the drinking water of broilers on a large-scale farm. To bridge this gap, starting from April 2023, alginate oligosaccharides powder was added to the drinking water system in a broiler farm in this experiment, and the weight gain and mortality and culling of broilers were recorded. The results indicated that there was a 0.22 kg difference in the average market weight of broilers between the alginate oligosaccharides group and the control group, and the difference in mortality and culling was highly significant (P < 0.001). Additionally, the economic benefits of alginate oligosaccharides as a feed additive were further substantiated through cost accounting. These findings not only furnish a scientific basis for the application of alginate oligosaccharides in broiler farming but also offer a new reference for farmers in the selection of feed additives.