Lung auscultation recordings from normal sheep and from sheep with well-defined respiratory tract pathology

Increased audibility of normal lung sounds is commonly caused by hyperventilation after exercise and during hot weather. Tachypnoea is common in toxaemic and septicaemic conditions, but there may be no adventitious sounds. Moderate to pronounced coarse crackles are readily identified in advanced cases of ovine pulmonary adenocarcinoma, but auscultation findings do not correspond well to the distribution of lesion(s) revealed at necropsy. Auscultation does not detect pleural abscesses (up to 10cm diameter). Marked attenuation of normal lung sounds results from marked fibrinous pleurisy and extensive unilateral pyothorax. Pleural frictions rubs are not heard in cases of marked fibrinous pleurisy associated with pleural abscesses. Rumen contraction sounds are often superimposed upon lung sounds. Auscultation of the ovine chest alone does not allow the clinician to determine the presence of all superficial lung pathology nor accurately define its distribution. Ultrasonography provides more accurate information regarding the nature and extent of superficial lung pathology in sheep.