Summer pasture-associated obstructive pulmonary disease in horses: 21 cases (1983-1991).

This research article investigates cases of obstructive pulmonary illness in horses, mainly caused by summer pastures. The study focuses on the symptoms, clinical records, and treatment responses of 21 horses over an 8-year period.

Subject and Purpose of the Research

• The study revolves around the medical records of 21 horses diagnosed with summer pasture-associated obstructive pulmonary disease, dating from the years 1983 to 1991.
• The main purpose of the study was to observe trends in the disease’s history, signalment (the description of the subject), clinical signs, radiographic signs, clinicopathologic data, and therapeutic response over the course of these years.

Patient Details

• The age range of the horses was around 13.7 years ± 3.6. Mostly, these horses were used for leisure and stayed in pastures when not in use.
• The focus on these horses’ lifestyle gives perspective on how environmental factors such as summer pastures might affect their health conditions and contribute to the occurrence of obstructive pulmonary disease.

Clinical Signs and Diagnosis

• The clinical symptoms of the disease included intermittent nasal discharge, cough, tachypnea (rapid breathing), laborious exhaling, and audible crackles and wheezes in the lungs during auscultation (listening to sounds within the horse’s body).
• Radiographic views of the horses often showed an interstitial pattern in the lung fields, indicating some form of lung disease.
• Horses with long-standing disease exhibited pulmonary overinflation—an abnormal expansion of the lung—or other significant lung changes.

Laboratory Findings and Analysis

• Usually, the horses’ hemogram—or complete blood count—was normal, suggesting that the condition primarily affected their respiratory system with no apparent impact on the circulatory system.
• The study found that the horses’ transtracheal wash (TTW) fluid—used to diagnose lung diseases—was dominated by nondegenerate neutrophils, indicating an inflammatory response in the horses’ respiratory tract.