Surgical amputation of polymelia in a broiler chicken (Gallus gallus domesticus) with caudal duplication syndrome

Abstract

Abstract Background : Caudal duplication syndrome is a rare developmental anomaly thought to be a result of incomplete twinning. Case Description : A 6-week-old female broiler chicken (Gallus gallus domesticus) presented to a private specialty exotic animal hospital, for evaluation of accessory hindlimbs due to one of the limbs becoming soiled with feces causing localized dermatitis. The bird had been rescued from culling at an undisclosed private poultry farm. Diagnostic evaluation included whole body radiographs and computed tomography. Radiographic and CT images confirmed an accessory malformed pelvis and fused femur, left lateral deviation of the coccygeal spine and pygostyle. CT images further revealed a paired proctodeum exiting through a single fused vent also deviated to the left. Surgical removal of the accessory limbs was successful and the chicken was healthy on follow up examination 12 months following initial presentation. Conclusion and Case Relevance : This case documents polymelus anomalies and caudal duplication syndrome in an avian patient and shows a long-term positive surgical outcome for a chicken treated for these conditions.