What’s new in research on companion animal neutering?
25 February 2025
To mark World Spay Day – a day dedicated to promoting the spaying and neutering of pets – we’re looking at a selection of new research in neutering companion animals.
Comparison of postoperative pain and stress using a multimodal approach in cats: open vs. laparoscopic-assisted ovariohysterectomy. Jeong et al. Frontiers in Veterinary Science.
Postoperative pain, surgical complications, and recovery were compared between two-port laparoscopic-assisted ovariohysterectomy (LAOHE) and open ovariohysterectomy (OHE) in 30 healthy cats in this study. Cats that underwent LAOHE had significantly lower pain scores at 1, 4, and 8 hours postoperatively, and significantly lower cortisol levels compared to those that underwent OHE, without an increase in surgical time or complications. These findings show that while both LAOHE and OHE are safe and effective for elective ovariohysterectomy in cats, LAOHE significantly reduces postoperative pain and stress compared with traditional OHE, and may be a preferable technique.
Use of a quadratus lumborum block in queens undergoing ovariectomy: a randomised controlled trial. Paolini et al. Journal of Feline Medicine and Surgery.
This is the first study to compare the perioperative analgesic effect of a quadratus lumborum (QL) block in 37 healthy queens undergoing ovariectomy, with a control group. All cats were premedicated with dexmedetomidine 0.005 mg/kg, alfaxalone 1 mg/kg and methadone 0.1 mg/kg intramuscularly. Cats were randomised to receive a bilateral ultrasound-guided QL block with 0.4 ml/kg of ropivacaine 0.4% (3.2 mg/kg) under general anaesthesia, whilst no treatment was administered to cats in the control group. Use of a QL block resulted in lower intraoperative rescue fentanyl requirement, with no adverse effects or complications observed.
Later-age neutering causes lower risk of early‐onset urinary incontinence than early neutering–a VetCompass target trial emulation study. Pegram et al. PLOS ONE.
This study compared the causal effects between neutering at early age or later age on subsequent diagnosis with early-onset urinary incontinence (UI) in a cohort of 30,953 bitches in the VetCompass database. The odds of developing early-onset UI were 20% lower in bitches neutered later (≥7 to ≤ 8 months) compared with an earlier age (3 to <7 months). Whilst neutering decisions are influenced by various factors as well as UI risk, these findings suggest that preference should be given to delaying neutering until after 7 months of age, unless other major reasons justify earlier.
Cardiorespiratory, analgesic and gastrointestinal effects of fentanyl and lidocaine in rabbits (Oryctolagus cuniculus) undergoing ovariohysterectomy. Fuchs et al. Journal of Exotic Pet Medicine.
The effect of three different analgesic protocols – lidocaine, fentanyl, and fentanyl+lidocaine – on cardiorespiratory variables, postoperative pain control, and fecal production was assessed in 19 New Zealand White rabbits undergoing elective ovariohysterectomy (OVH). Fentanyl and fentanyl+lidocaine caused a reduction in body weight for seven days postoperatively, a reduction in water and food intake and fecal output, mostly for two days postoperatively, and reduced heart and respiratory rate. Rabbits given lidocaine alone needed higher concentrations of isoflurane to maintain anaesthetic depth and two animals required analgesic rescue, suggesting that lidocaine infusion should only be included within a multimodal analgesia protocol. There was no difference in pain scores between groups. These findings suggest that continuous infusion of fentanyl and lidocaine may contribute to adequate analgesia in rabbits undergoing OVH.
The association between gonadectomy and timing of gonadectomy, and the risk of canine cranial cruciate ligament disease: A systematic review and meta-analysis. Low et al. Veterinary Surgery.
This systematic review of 24 relevant studies on gonadectomy and cranial cruciate ligament disease (CrCLD) found that gonadectomy is associated with increased odds of developing CrCLD in both sexes, particularly in dogs gonadectomized at 1 year of age or less. This may be useful for clinical decision-making on gonadectomy and the timing of gonadectomy.
BSAVA resources on neutering