Morphology of a dicephalic cat

Abstract

A detailed anatomical study of a dicephalic iniodymic monosomic cat in conjunction with the morphogenetical implications of the observed anomalies is presented. The animal exhibited two heads joined at the level of an anomalous medial exoccipital bone. Two brains and two foramina magna were present. The vertebral column was single but the cranial cervical vertebrae (C2 to C5) had doubled bodies. Cervical rachischisis with myeloschisis were associated defects. Two nasopharyngeal and oropharyngeal cavities converged caudally into a single laryngopharynx. The esophagus, larynx and trachea were single. Duplication of the tongue and hyoid apparatus was present. Palatoschisis affected both oral cavities. Hypoplasia of the anatomical structures in the medial aspects of both heads was observed. Microphthalmia was also observed in both medial eyes. Comparative aspects of the morphology, causative agents, and mechanisms and anomalous morphogenesis of anterior duplications are reviewed and discussed.

Persistent Truncus Arteriosus in a Diprosopic Newborn Calf

“…In view of the morphogenetical rearrangements taking place during development in duplication malformations (reviewed by CAMON et al, 1992) and the appearance of excess or defective anomalies, it may be possible that the precise temporospatial migration and distribution of ectomesenchymal cells derived from the neural crest (MIYAGAWA-TOMITA et al, 1991) results in insufficient cells arriving at the proper time and in sufficient quantities to contribute to the normal development of the derivatives from the pharyngeal arches, aortic arches, pharyngeal pouches and conotruncal septum of the embryonic heart.…”

Prenatal Diagnosis of Canine and Feline Twins Using Ultrasound: A Retrospective Study

“…However, monochorionic twins have been described macroscopically in dogs at birth [37][38][39]. Instead, different reports describe conjoined twins (monochorionic monoamniotic twins) in cats [40][41][42] and dogs [43][44][45][46][47]. Despite these case reports, this is the first study that attempted to evaluate the prevalence of twins in these species using ultrasonography.…”

Conjoined Sternophagus Twin Monster: A Cause of Dystocia in Murrah Graded Buffalo

“…Grossly the fetus possessed two normal heads, with separate nostrils, eyes and ears. According to Camon [10] dicephalic fetus could manifest any of the following Atlodymus (two complete and separate skulls and single neck), Iniodymus (two skulls with fusion at the occipital region) and derodymus (two complete and separate skulls with two separate necks). In accordance with this nomenclature, the present fetus was derodymus dicephalic, distomus, tetraopthalmus, tetraotus, tetrabrachius, tetrapus, and dicaudatus conjoined sternopagus twin monster male buffalo calf (Figure 1).…”