Abstract: The equine respiratory tract is so highly specialized for exercise that even the slightest deviation from normal can limit a horse’s career. The equine respiratory tract has several functions including intake of air for oxygenation of blood, thermoregulation by evaporative cooling, compensatory mechanism and play important role in defense mechanism. Respiratory tract affections of equines include both upper respiratory tract disorders like sinusitis, epistaxis, nasal polyps, strangles, guttural pouch empyema, rhinitis and lower respiratory tract disorders like bacterial and viral pneumonia (broncheo-alveolar and interstitial), pleuritis, neoplasia of lungs etc. Pneumonia the most commonly reported condition in working horses. The present study was conducted in equines suspected for respiratory tract affections reporting to Department of Veterinary Clinical Complex, College of Veterinary Sciences, Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar or from an organized farm over a period of 5 months. Pulmonary affections in animals were diagnosed mainly with the help of diagnostic imaging techniques like radiography and ultrasonography. Clinico-pathological studies of pulmonary affections of equines in relation to haemato-biochemical parameters was evaluated and interpreted. Neutrophilic leucocytosis was observed in all the categories of pulmonary affections in the present study There were significant increase in ALP (216.5±19.027), BUN (17.91±1.554), globulin (4.0813±0.153) and triglycerides (45.012±5.414) value as compare to control groups. The mean value of creatinine (1.0875±0.183) and LDH (774.75±33.933) were decreases which may or may not be significant. Hypalbuminaemia was present in all clinically affected pulmonary diseases. The mean value of glucose (62.7±4.484) was significantly decreased mainly in case of fibrinous pleuritis at level of significance (P<0.05) as compare to control group.
