Gross pathological diagnosis of pygomelia in association with other anomalies in a 3-week old Chick-layer

Abstract

Malformations may be found in chickens with or without fatal consequences depending upon the nature of such anomalies and their ability to interfere with the normal physiology of affected birds. The present report aimed to document a case of polymelia in general, and pygomelia in particular, in association with other anomalies in a 3-week old Chick-layer. A post-mortem examination was carried out on the Chick-layer immediately following death from wild rat’s attack in a make-shift metal isolation pen while awaiting clinical examination. Although the Chick-layer looked slightly smaller than its peers on the average, it was in a fair body condition. The Chick-layer had a pasted vent. It also had a pair of legs attached to the pelvis beneath the left side of its coccygeal vertebrae, which displaced the cloaca laterally to its right. We did not observe visible gross morphological changes in visceral organs. However, the Chick-layer had a dilated and impacted rectum/cloaca with three ceca. Based on the available literature, this is the first report of pygomelia with these peculiar types of associated cecal and rectal anomalies in a Chick-layer. The continuous documentation of the various forms of this condition with their associated anomalies will enrich our knowledge base in the subject matter for a better understanding of the triggers, pathogenesis, management, and the prevention/control measures against these developmental anomalies in affected birds.