Radiographic imaging of the thorax in newborn calves with anorectal anomalies

Abstract

The present study aimed to understand the radiographic anatomy of the thorax in newborn calves and to investigate the effect of anorectal anomalies on respiratory and cardiovascular structures. The study included thirty newborn calves. All were male except four. Their ages ranged from 1 to 5 days. Upon arrival at the Veterinary Teaching Hospital (VTH), the animals underwent clinical and radiographic examinations. The calves were divided into two groups: the anorectal group (n=19) and the non-anorectal group (n=11). The radiographic examination focused on both the abdomen and thorax in the first group, while the second group was assessed primarily for other conditions, such as mandibular or limb fractures, alongside thoracic evaluation. Two lateral radiographic views of the thorax were obtained for each animal. Key measurements were taken, which included the cranial pulmonary blood vessels, vertebral heart score (VHS), diameter of the caudal vena cava (CVC), diameter of the aorta, tracheal diameter, thoracic inlet, thoracic length, and thoracic axis. The size of the heart was evaluated according to the Fernández method. The results indicated that there were no significant changes in clinical examination findings between the two groups, except for an increased respiratory rate in the anorectal group. Radiographic findings showed no significant differences between the right and left lateral views within each group. However, clear differences were observed between the anorectal and non-anorectal groups in terms of cardiac long axis (CLA), cardiac short axis (CSA), VHS, thoracic length, and thoracic axis (P < 0.05). There was no significant change in heart size according to the Fernández method between the two groups. In conclusion, radiography is a valuable tool for understanding the thoracic anatomy of newborn calves. Anorectal anomalies lead to significant changes in some thoracic structures due to abdominal distension and pressure on the diaphragm. Additionally, different methods for assessing cardiac size are unreliable and should not be solely relied upon for definitive conclusions about heart size.