A novel approach for urethral catheterization in dromedary camels: a preclinical study.

Abstract

BACKGROUND: Urethral obstruction due to urolithiasis is an uncommon problem reported in dromedary camels. Urethral catheterization is recommended as an emergency preliminary alternative to palliative urethrostomy to preserve valuable animals for breeding purposes. This procedure is not possible in camels due to the narrow diameter of the tortuous urethra, presence of sigmoid flexure and urethral recess and unavailability of specific full-length catheter. OBJECTIVE: To assess the normograde catheterization of the camel urethra through cystotomy incision by using 6-Fr, 70 cm, PVC straight-tip ureteric catheter with a central opening. METHODS: Fifteen fresh penile specimens were utilized to obtain detailed surgical anatomy of the male urethra and to evaluate the normograde passage of a 6-Fr, 70 cm, PVC straight-tip ureteric catheter with a central opening, followed by X-ray imaging and casting of the urethra. The feasibility of the catheterization process was assessed. The urethral cast was employed to imprint the internal diameter of the urethra and identify potential sites for calculi lodgment. Samples from potential areas were examined to reveal any histopathological relevance. RESULTS: The normograde passage of the rigid ureteral catheter was feasible and encompassed the entire urethra, as confirmed by X-ray imaging. The urethral cast revealed a remarkably narrow diameter (2 mm) of the penile urethra. The preputial portion of the urethra emerges as a potential site for calculi lodgment, attributed to its small diameter and the thin layer of urethralis and bulbospongiosus muscle responsible for urine expulsion. CONCLUSION: The normograde catheterization of the camel urethra with rigid ureteral catheter is feasible and may be a valuable preliminary intervention for calculi removal before surgical urethrotomy or urethrostomy.