Determination of vertebral heart scale reference ranges in Gazelles subgutturosa

Species-specific reference data for radiographic evaluation of cardiac structures in gazelles (Gazella subgutturosa) are limited; therefore, this prospective anatomical reference range study aimed to initiate the determination of vertebral heart scale values in clinically healthy young gazelles and evaluate the possible effects of position, sex, and age on these measurements. Twenty healthy gazelles aged between 0 and 6 months (10 females and 10 males) were included in the study. Right lateral and ventrodorsal thoracic radiographs of all individuals were obtained during the full inspiration phase. The long and short axes of the heart were measured digitally, and the sum of these measurements vertebral heart scale was recorded in vertebral units using the fourth thoracic vertebra as the reference point. The mean vertebral heart scale values were determined to be 9.59 ± 0.59 vertebral units in the right lateral position and 9.61 ± 0.58 vertebral units in the ventrodorsal position, with no statistically significant difference between the positions (P=0.494). The long-axis measurement was significantly greater in the ventrodorsal position than in the right lateral position (P=0.001); however, this difference was not reflected in the total vertebral heart scale value. No significant differences were detected between the sexes in terms of the vertebral heart scale or cardiac axis measurements (P>0.05). Measurement repeatability was found to be high, and inter-observer agreement was assessed as excellent (Intraclass Correlation Coefficient = 0.91; 95% CI: 0.85–0.96; P