Esophageal dysfunction in four alpaca crias and a llama cria with vascular ring anomalies

• Published in: Journal of the American Veterinary Medical Association Vol. 237; no. 3; pp. 311 - 316
• Main Authors: McKenzie, Erica C, Seguin, Bernard, Cebra, Christopher K, Margiocco, Marco L, Anderson, David E, Lohr, Christiane V
• Format: Journal Article
• Language: English
• Published: United States 01.08.2010
• Subjects: alpacas; Animals; aorta; Camelids, New World; case studies; complications; congenital abnormalities; diagnostic techniques; digestive physiology; disease severity; Esophageal Diseases - etiology; Esophageal Diseases - surgery; Esophageal Diseases - veterinary; esophagus; etiology; Female; Heart Defects, Congenital - complications; Heart Defects, Congenital - surgery; Heart Defects, Congenital - veterinary; image analysis; llamas; Male; megaesophagus; mortality; pathophysiology; resection; vascular ring anomaly; young animals
• ISSN: 0003-1488; 1943-569X
• DOI: 10.2460/javma.237.3.311

3 alpaca crias and cadavers of an alpaca cria and a llama cria were evaluated for evidence of esophageal dysfunction. All 5 crias were between 3 and 5 months of age when clinical signs developed, and all had a thin body condition when examined. Clinical signs included coughing, regurgitation, and grossly visible esophageal peristaltic waves. A barium esophagram was used to diagnose esophageal obstruction, megaesophagus, and a vascular ring anomaly (VRA). Fluoroscopy was used to evaluate deglutition, esophageal peristalsis, and the extent of esophageal dilation in 1 alpaca cria. A persistent right aortic arch was identified in 1 alpaca cria, and a left aortic arch with right ductus arteriosus or ligamentum arteriosum and an aberrant right subclavian artery were identified in the 4 remaining crias. Surgical correction of the VRA was attempted in the 3 live alpaca crias. It was complicated by the conformation and location of each VRA and inaccurate anatomic diagnosis of the VRAs before surgery. Treatment was universally unsuccessful because of intraoperative complications and the persistence of clinical signs after surgery. Megaesophagus is typically an idiopathic condition in camelids. However, these findings suggested that camelids with esophageal dysfunction during the neonatal period may have a VRA. The prognosis is grave for camelids with VRA, and accurate anatomic diagnosis of the VRA via the use of advanced imaging techniques (eg, angiography, computed tomography, or magnetic resonance imaging) may improve the success of surgical intervention.