Sudden Death Syndrome of Feeder Cattle

A Proposal for a New Approach

Abstract

Sudden death syndrome (SDS) of feeder cattle is the occurrence of unexpected deaths of feeder cattle in their home feeding pen.¹ Cattle fitting this classification show an unclear cause of death, even after postmortem examination. Occurrence is sporadic and it is currently impossible to predict when or which cattle will be affected. The cattle are not observed moribund antemortem; they are rarely observed in the process of dying and they never leave evidence of antemortem discomfort or struggle.^2,3

Cases of SDS are defined by the following criteria: animals are found dead with no recent sign of illness noted; necropsy findings indicate the animals did not die from any of the commonly recognized causes of death in feedyard cattle; deaths seem to occur in cattle which have been in the feedyard more than 45 days; post-mortem decomposition appears to proceed at an accelerated rate and it is more pronounced in the small intestine, liver and kidney than in surrounding tissues; abnormalities seen on post-mortem examination of the carcasses are generally referable to antemortem metabolic abnormalities, and these abnormalities are subtle and often in the process of being obliterated by the accelerated decomposition.^3,4 Incidence seems to vary between yards and with season or weather.³