Bovine Interstitial Pneumonia Study Guide

Overview and Clinical Importance

Acute Bovine Pulmonary Emphysema and Edema (ABPEE), also known as fog fever, atypical interstitial pneumonia (AIP), or bovine asthma, is a toxic interstitial pneumonia characterized by acute respiratory distress in cattle. This condition represents a significant cause of sudden death in adult pastured cattle and is an important topic for the NAVLE examination.

The disease occurs most commonly in late summer and fall when cattle are moved from dry, sparse pastures to lush, rapidly growing forage. The condition develops 5-10 days after pasture change and can affect up to 50% of exposed cattle, with mortality rates reaching 30% in severe outbreaks.

Etiology and Pathophysiology

Primary Cause: L-Tryptophan Metabolism

The primary etiology involves the amino acid L-tryptophan found in high concentrations in lush, rapidly growing pasture grasses. The pathogenesis follows a specific metabolic pathway: