Pulmonary function values and growth in Belgian white and blue double-muscled cattle

Seventy-five double-muscled cattle of the Belgian white and blue breed, two days to 50 months old and weighing 45 to 680 kg, were investigated. Transpulmonary pressure changes, measured with an oesophageal balloon, variations of air flow and volume at the mouth were obtained during spontaneous breathing to calculate pulmonary function data. Oxygen and carbon dioxide tensions in arterial blood were also recorded. Growth related changes of the pulmonary function values were similar to those observed in other bovine breeds. Total pulmonary resistance, specific total pulmonary resistance, viscous work, power of breathing, specific viscous work, respiratory frequency and peak-to-peak change in transpulmonary pressure were greater in Belgian white and blue cattle than in Friesian cattle. In the former, tidal volume, specific tidal volume, lowest transpulmonary pressure during expiration, transpulmonary pressure at the functional residual capacity level, dynamic lung compliance and oxygen tension in arterial blood were smaller. Airflow, minute volume and carbon dioxide tension in arterial blood were similar in the Belgian white and blue and Friesian cattle. These results were related to the great sensitivity of double-muscled cattle of the Belgian white and blue breed to laryngitis and bronchopneumonia.