The Welfare Absence Means Pathology: An Example of Abomasal Ulcers and Fatal Peritonitis in Feedlot Calves

Abstract

worldwide (Earley et al ., Panciera and Abstract | A mortality outbreak in calves entered directly in a feedlot was reported. Mortality reached 24% in three days and morbidity was close to 60%. Animals arrived in feedlot three to four days before during the weekend and overwhelmed the expected entrance in 300%. Upon arrival the animals (among 7 to 8 months old, weighing 180-200kg) were received in a hallway employed to provisionally keep animals before assignment in a pen. The hallway was crowded to the point that the animals were restrained and many of them were unable to reach the sole drinker. No food was provided. The next Monday morning, animals were routinely processed (almost 60 h after) and assigned to a pen with drinkers and corn straw in feeders. However, that day many animals suddenly died (90), and many more (114), succumbed during the following two days (204/850=24%). The post mortem exams registered bronchopneumonia and abomasal ulcers, many of them (62 cases/204=30.4%) perforated causing peritonitis, in absence of severe bronchopneumonia. At first time, abomasal ulcers were considered a new syndrome with suspected clostridial disease or poisoning. A proposal pathogenesis established an initial intolerable stress causing ulcers and subsequently, the hunger forced aggressive consumption of straw corn stalks provoking ruminal bloat with distended (or displaced) abomasum, resulting in ischemic necrosis of the ulcer edges with perforation and fatal peritonitis.