A form of congestive heart failure is increasingly reported as a cause of death in feedlot cattle located at moderate altitude (β€ 1524 m.). Significant knowledge gaps exist in the epidemiology and management of this form of bovine congestive heart failure (BCHF) regarding frequency and timing of BCHF cases and ways in which beef cattle producers and veterinarians can mitigate this condition. These knowledge gaps present major barriers to understanding the mechanism of BCHF and mitigating the consequences of BCHF. The purpose of this thesis is to summarize current knowledge about BCHF, define gaps in knowledge for which more research is needed, formulate hypotheses regarding the knowledge gaps, and discuss two studies designed to test those hypotheses related to the emergence of BCHF. The first study presented is designed to estimate the frequency and timing of BCHF case development. The second study was completed to evaluate the effect of moving two bulls affected by pulmonary arterial hypertension from their ranch of origin to lower elevation as a possible management strategy for mitigation of pulmonary arterial hypertension. Results presented in this thesis provide evidence that the frequency of BCHF cases has increased over the course of six years in the feedlot studied and changing the environment of animals affected by pulmonary arterial hypertension by moving them to lower altitude can lead to a decrease in pulmonary arterial pressure. This thesis will interpret the results of both studies to highlight how these data can aid in understanding the underlying mechanism of BCHF.
Advisor: Brian L. Vander Le
