Sudden death syndrome in domestic ruminants: a review

This review provides a comprehensive exploration of factors contributing to sudden death (SD) in ruminants, focusing on cattle, sheep, and goats. The definition of unexpected death varies based on the farming system. In intensive systems, constant surveillance enables rapid detection of diseases, while in extensive systems, irregular checks may result in finding animals dead after a prolonged illness. SD syndrome definitions vary; some involve clear clinical signs, while others consider acute death in apparently healthy animals. Various infectious causes of SD are discussed, including enterotoxemia, hemorrhagic bowel syndrome, caudal vena cava thrombosis, and respiratory diseases. The review also covers nutritional disorders like acidosis, hypomagnesemia, and vitamin deficiencies. Poisoning, both from inappropriate drug use and toxic plants, is examined, as well as accidents and trauma, parasitism, stress, and miscellaneous causes such as aortic aneurysm rupture, congenital defects, and snakebites. Differential diagnosis is emphasized, and the importance of post-mortem examinations in understanding the cause of unexpected deaths is highlighted. The paper offers a detailed overview of the complex factors contributing to SD in ruminants, emphasizing the need for thorough investigations and necropsy examinations to identify the specific cause in each case.