Radiographic appearance of the thorax of clinically normal alpaca crias.
OBJECTIVE
To quantitatively and qualitatively assess the radiographic appearance of the thorax of clinically normal alpaca crias.


METHODS
21 clinically normal alpaca crias.


METHODS
Left-right lateral (LR), right-left lateral (RL), dorsoventral (DV), and ventrodorsal (VD) projections of the thorax were acquired. To account for differences in cria size, measurements of thoracic structures were compared with other anatomic landmarks.


RESULTS
Mean ± SD vertebral heart scale was 9.36 ± 0.65 for LR projections, 9.36 ± 0.59 for RL projections, 8.21 ± 0.51 for DV projections, and 8.65 ± 0.57 for VD projections. Dimensions of the heart were compared with the length of the T3 through T5 vertebral bodies, third to fifth rib distance, and thoracic height and width, which provided additional methods of cardiac evaluation. For RL projections, mean ratio of the right cranial pulmonary artery diameter to the third rib width was 0.41 ± 0.10 and mean ratio of the right cranial pulmonary vein to the third rib width was 0.44 ± 0.10. Caudal lobar pulmonary vessels and the caudal vena cava were difficult to quantitatively assess on DV or VD projections. On lateral projections, the trachea was increased in diameter at the origin of the right cranial lobar bronchus. No qualitative differences were found between LR and RL radiographs. The lungs were generally better inflated on VD projections, with more separation of the heart and diaphragm.


CONCLUSIONS
Establishment of radiographic values for alpaca crias should prove useful in assessment of thoracic disease in this species.
Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48864, USA. nelso329@cvm.msu.edu
Nathan C
NC
Nelson
John S
JS
Mattoon
David E
DE
Anderson
D000367:Age Factors; D059925:Anatomic Landmarks / Q000000981:diagnostic imaging; D000818:Animals; D002161:Camelids, New World / Q000033:anatomy & histology*; D003964:Diaphragm / Q000000981:diagnostic imaging; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging*; D008168:Lung / Q000000981:diagnostic imaging; D008297:Male; D013902:Radiography, Thoracic / Q000662:veterinary*; D012015:Reference Standards; D012016:Reference Values; D012137:Respiratory System / Q000000981:diagnostic imaging*; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging; D013909:Thorax / Q000098:blood supply*; D014132:Trachea / Q000000981:diagnostic imaging; D014684:Venae Cavae / Q000000981:diagnostic imaging