In 85 Holstein calves aged 2-28 days, indicators characterizing respiratory moisture loss (RML) and their association with airway inflammation were studied. Animals were evaluated by clinical scoring system WI. 66 calves had a WI clinical score of more than 3 points or less (healthy), 19-more than 3 points (sick). To study RML in animals, exhaled breath condensate was collected using a special device (patent RU 134772 U1) and its volume generated in 1 minute and from 100 L of exhaled air was measured. It was found that in healthy calves, RML is 0.030-0.124 mL per minute and 0.242-1.506 mL per 100 L of exhaled air, in sick calves they increase on average by 24.3% (P <0.01) and 50.4% (P <0.001), respectively. Thus, airway inflammation increases RML in animals. Current results show that RML intensity in calves increases markedly with increasing body temperature, WI clinical score and correlates with pulmonary ventilation.