Introduction

Transport losses in market weight pigs (dead and nonambulatory pigs) represent animal welfare, legal, and economic concerns to the US swine industry. 1 First of all, improving the well-being of pigs during transport and reducing the incidence of dead and non-ambulatory pigs are animal welfare priorities for the US swine industry. 2 Secondly, non-ambulatory livestock are the subject of increased rules and regulations. For example, United States Department of Agriculture (USDA) inspectors and plant welfare auditors evaluate how non-ambulatory pigs are handled at the packing plant. Improper handling of non-ambulatory pigs at the plant can result in a USDA non-compliance report and/or a failed plant welfare audit.3•4 Thirdly, transport losses represent direct financial losses to pork producers and packers, and these losses have been estimated to cost the US swine industry approximately $50 to $100 million annually.5 The objectives of this paper are to: 1) define transport losses; 2) estimate the US incidence of transport losses; 3) describe the symptoms and metabolic characteristics of fatigued pigs; 4) discuss pre-disposing factors for transport losses; 5) illustrate the seasonal variation in transport losses; and 6) outline management strategies to reduce these losses.