Читать книгу Bovine Reproduction - Группа авторов - Страница 333

Medical management is often unrewarding in the treatment of urolithiasis unless instituted early in the disease course. If the obstruction is recognized early, conservative therapy can be attempted with spasmolytic drugs and tranquilizers [2, 21, 22]. Phenothiazine tranquilizers are typically utilized which decrease urethral spasm and induce relaxation of the retractor penis muscles and straightening of the sigmoid flexure [2, 22]. In early cases, straightening of the sigmoid flexure and decreased urethral spasms may help urethral calculi to pass. However, if unsuccessful, retrograde urethral catheterization with hydropulsion can be attempted.

Retrograde catheterization is most easily performed in mature bulls versus castrated or prepubertal males due to the presence of persistent frenulum. Once exteriorization of the glans penis is accomplished, retrograde catheterization can be attempted with 8‐ to 10‐French polypropylene tubing. Infusion of lidocaine may assist with urethral spasm prior to attempting hydropulsion with saline. If significant resistance occurs, further attempts should be abandoned to prevent further urothelial trauma, and surgical intervention is necessary. Catheterization and hydropulsion are typically unsuccessful in cattle due to the presence of the urethral diverticulum and the chronicity in which most individuals present.