Complex Body Wall Closure Defects in Seven Dog Fetuses: An Anatomic and CT Scan Study.

Area of Science:

• Veterinary Pathology
• Developmental Biology
• Comparative Embryology

Background:

• Body stalk anomaly (BSA) is a rare, often fatal congenital disorder characterized by severe malformations.
• Previous reports of BSA have primarily focused on pigs and cats, with limited documentation in canines.

Purpose of the Study:

• To document the first cases of body stalk anomaly (BSA) in dogs.
• To expand the known phenotypic spectrum of BSA in domestic animals.
• To contribute to understanding the pathogenesis and etiology of BSA.

Main Methods:

• Case documentation of seven canine fetuses diagnosed with BSA.
• Phenotypic characterization of observed malformations, including body wall, limbs, spine, and internal organs.
• Comparison with existing literature on BSA in other species.

Main Results:

• Consistent major anomalies observed: large abdominal wall defects, spinal abnormalities, and diverse limb malformations (agenesis, meromelia, phocomelia, amelia).
• Associated urogenital and orofacial cleft anomalies were noted.
• Findings align with BSA presentations in pigs and cats, suggesting shared developmental pathways.

Conclusions:

• The canine cases support a multifactorial etiology for BSA, involving early embryonic disruptions like abnormal folding, amniotic rupture, or vascular compromise.
• Abdominal wall defects and umbilical cord abnormalities suggest a shared developmental pathway.
• Veterinary cases are valuable for comparative embryology, aiding in the classification and diagnosis of complex congenital malformations across species.