Atresia ani in the dog: a retrospective study

Area of Science:

• Veterinary Medicine
• Canine Surgery
• Developmental Biology

Background:

• Congenital anomalies of the rectum and anus are rare in dogs.
• Atresia ani is the most frequently reported anomaly, with four distinct types identified.
• Certain breeds, like miniature/toy poodles and Boston terriers, and female dogs show an increased incidence.

Purpose of the Study:

• To review the classification and characteristics of congenital rectal and anal anomalies in dogs.
• To highlight the common types, breed predispositions, and sex predilections.
• To discuss the primary treatment and potential postoperative complications.

Main Methods:

• Literature review of congenital rectal and anal anomalies in veterinary databases.
• Classification of atresia ani into four types based on anatomical description.
• Analysis of reported breed and sex incidences.
• Summary of surgical treatment and common complications.

Main Results:

• Four types of atresia ani are described: Type I (stenosis), Type II (imperforate anus), Type III (blind pouch), and Type IV (discontinuity).
• Increased incidence noted in female dogs and specific breeds (miniature/toy poodles, Boston terriers).
• Surgical repair is the recommended treatment, but complications such as fecal incontinence and colonic atony can occur.

Conclusions:

• Congenital atresia ani in dogs presents with varied anatomical classifications.
• Breed and sex influence the occurrence of these anomalies.
• While surgery is effective, careful management is needed to mitigate potential postoperative complications like incontinence.