Comparative radiographic morphometry of thorax in upto one month old healthy buffalo and cow calves

Abstract

The study was aimed to record the radiographic morphometry of thorax in buffalo and cow calves of up to one month of age and to compare them between the two species.
The study included 17 buffalo and 13 cow calves (5 local breeds and 8 crossbred exotica). All the calves were subjected to lateral chest radiography in a recumbent position, without sedation or anesthesia. For evaluation purposes, the parameters were divided into the thoracic wall (thoracic inlet diameter, thorax dimensions, number and size of each sternebra, thoracic depth), airway (tracheal lumen diameter, carina diameter, tracheal inclination angle, tracheal lumen, and thoracic inlet diameter ratio, thoracic inlet, and thoracic depth ratio), major vessels (aorta and caudal vena cava at various level and their ratios), cardiac (length, width, vertebral length, rib 4 diameter, heart size in relation to the number of sternebrae, rib and intercostal space, vertebral left atrial score, sternal contact of heart, cardiac inclination angle and their various ratio) and the diaphragm (cupula height and placement in relation to rib, sternum, caudal vena cava height at diaphragm, diaphragm crus placement in relation to vertebrae) region.
In 94% of buffalo calves the number of sternebrae was 7 while, one calf had 8 sternebrae with the 7th smaller in length. However, 69.23% of cow calves (9 out of 13) had 7 sternebrae, and 4 calves had only 6 sternebrae (all exotic crossbred) with S6 missing. Out of 9 calves with 7 sternebrae, the S6 was very small in 66.67% (6/9) of the calves and the S6 was a block vertebra with no/little joint space with adjoining S5 or S7 in 4 calves (30.76%). The thoracic depth, sternal length, diagonal thorax measurements, body weight, and length of the S1, S2, S3, and S6 sternebra of buffalo calves were significantly more than that of cow calves. However, the thoracic inlet to thoracic depth ratio of buffalo calves was significantly less than the cow calves.
The maximum tracheal diameter, the tracheal inclination angle, and the ratio of trachea to thoracic inlet diameter of buffalo calves were significantly more in comparison to cow calves. The cardiac inclination angle and the thoracic depth of the buffalo calves were significantly more than the cow calves; however, the heart length to thoracic depth ratio was more in cow calves.
The vertebral left atrial score recorded by two described methods in dogs was found to be significantly different for bovine calves. The cupula height from the sternum was found to be significantly more in buffalo calves compared to cow calves. In conclusion, a normal radiographic morphometry database of the thorax of buffalo and cow calves of up to one month of age was generated. Statistical anatomical differences in the thorax of cow and buffalo calves exist.