Ovariohysterectomy

Uses

• For the treatment and prevention of uterine pathology, eg adenocarcinoma Uterine adenocarcinoma, aneurysm, pyometra Pyometra, hydrometra , torsion, etc, and behavioral problems (aggression Aggression: female, sexual behavior, territorial marking Scent marking and spraying).
• Less commonly, for the treatment of unwanted pregnancy, pseudopregnancy Pseudopregnancy and ovarian neoplasia.
• Prophylactic ovariohysterectomy is usually performed between the ages of 5 months and 2 years (ideally between 5-8 months).

Print off the Owner factsheets Neutering - why and when and Caring for your rabbit before and after surgery to give to your clients.

Advantages

• Permanent prevention of breeding.
• Prevention of uterine conditions.
• Facilitates bonding.

Disadvantages

• Technically more difficult in obese or even moderately fat rabbits as the uterine and ovarian vessels are hidden within the fatty mesometrium and within the mesovarium, respectively. Rabbit does are better spayed before one year of age in order to avoid large amounts of fat in the mesometrium.
• The uterus becomes engorged in the pregnant or pseudopregnant female, making the associated blood vessels more friable for handling or suturing.
• The ovarian pedicle is friable and easily torn.
• Electro- or radio-cautery greatly assists the surgeon in achieving hemostasis of these vessels.
• Metal vascular clips reduce the risk of laceration and can considerably reduce the surgical time required for this procedure.
• If the uterus is removed caudal to the cervix, the reproductive tract must be sealed securely to prevent urine leakage into the abdomen.
• Ideally the ureters should be identified to avoid their accidental ligation; this is not usually necessary if most part of the vagina is left in place.
• Ovariohysterectomy may not alter behavior.
• Although uterine pathology is common in adult entire females, there is no scientific study assessing lifespan in neutered vs. entire female rabbits. Some breeds, eg New Zealand white New Zealand White, may be more predisposed than others to uterine pathology.

Technical problems

• Some young rabbits may be difficult to sex, particularly by inexperienced veterinarians or owners.
• Rabbits are prone to develop adhesions, which can produce chronic post-surgical pain.
• Full bladder and cecum can complicate visualization and surgery. A full bladder can be easily emptied using a sterile needle attached to a syringe. If the cecum is so full that precludes access to the ovary, then it should be carefully exteriorized and protected using wet swabs.

Alternative techniques

• Ovariectomy alone to control breeding or alter hormone-driven behavior.
• Ovariectomy in immature rabbits may be a quicker procedure than ovariohysterectomy whilst being effective in preventing uterine neoplasia.

Time required

Preparation

• 30 min to 1 h.

Decision taking

Risk assessment

• Pre-anesthetic assessment of the surgical patient.
• Greater risk in obese animals due to increased risk of hemorrhage from vessels within fat of ovarian ligament and uterine ligaments.
• The optimum age for spaying is 5-8 months.