The objective of this study was to identify risk factors associated with the frequency of fatigued and injured pigs in a commercial slaughterhouse.A retrospective study was performed to evaluate 4,758 pig batches that were unloaded at a slaughterhouse during the years 2012, 2013 and 2014.The incidence of non-ambulatory pigs was 0.44%, 0.41%, and 0.5%, respectively.The characteristics of producer and the driver, type of truck, month, and the distance were risk factors for the incidence of non-ambulatory pigs.The high frequency of downer pigs from farms showed the absence of emergency slaughter protocols and lack of implementation of good transporting practices.