AVMA Collections: Spay/Neuter

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Single-topic compilations of the information shaping our profession

June 2010

 
In this collection:
Summary:  Text | Audio 

Age at neutering

Impacts on health

Anesthesia

Pain management

Surgical risks

Alternative methods

Additional resources

 

Age at neutering



 
 
Determining the optimal age for gonadectomy of dogs and cats Highlights:
•   Shelter animals: Neuter before adoption
•   Pet animals should be considered individually
•   Health conditions are variously impacted
Consider benefits, detriments for each animal
Margaret V. Root Kustritz
J Am Vet Med Assoc 2007;231:1665-1675. December 1, 2007.
 
Long-term risks and benefits of early-age gonadectomy in dogs Highlights:
•   Incontinence higher in females spayed early
•   Obesity decreased in both sexes neutered early
•   Early-age gonadectomy safe in male dogs
Best to spay female dogs after 3-4 months of age
C. Victor Spain, Janet M. Scarlett, Katherine A. Houpt
J Am Vet Med Assoc 2004;224:380-387. February 1, 2004.
 
Long-term risks and benefits of early-age gonadectomy in cats Highlights:
•   Studied 1,660 cats adopted from shelters
•   Early-age gonadectomy beneficial in male cats
•   Asthma, gingivitis decreased in both sexes
Gonadectomy safe in cats under 6 months of age
C. Victor Spain, Janet M. Scarlett, Katherine A. Houpt
J Am Vet Med Assoc 2004;224:372-379. February 1, 2004.
 
Long-term outcome of gonadectomy performed at an early age or traditional age in dogs Highlights:
•   Health status of dogs monitored for 4 years
•   No increase in behavioral, body system issues
•   More infectious disease in early-age group
Early-age group generally no different
Lisa M. Howe, Margaret R. Slater, Harry W. Boothe, H. Phil Hobson, Jennifer L. Holcom, Angela C. Spann
J Am Vet Med Assoc 2001;218:217-221. January 15, 2001.
 
Long-term outcome of gonadectomy performed at an early age or traditional age in cats Highlights:
•   Health status of cats monitored for 3 years
•   No increase in physical or behavioral problems
•   No increase in infectious disease in either group
Early-age neutering did not increase problems
Lisa M. Howe, Margaret R. Slater, Harry W. Boothe, H. Phil Hobson, Theresa W. Fossum, Angela C. Spann, W. Scott Wilkie
J Am Vet Med Assoc 2000;217:1661-1665. December 1, 2000.
 
Correlation between age at neutering and age at onset of hyperadrenocorticism in ferrets Highlights:
•   Hyperadrenocorticism common in pet ferrets
•   Early-age neutering related to earlier onset
•   Loss of negative gonadal feedback may be factor
Treatment with GnRH agonist may be helpful
Nico J. Shoemaker, Marielle Schuurmans, Hanneke Moorman, J. (Sjeng) T. Lumeij
J Am Vet Med Assoc 2000;216:195?197. January 15, 2000.
 
 

Impacts on health

 
 
Effect of gonadectomy on subsequent development of age-related cognitive impairment in dogs Highlights:
•   Client-owned dogs 11 to 14 years old studied
•   More impairment in neutered vs. intact males
•   No sexually intact female dogs were studied
Testosterone may slow impairment progression
Benjamin L. Hart
J Am Vet Med Assoc 2001;219:51-56. July 1, 2001.
 
Effects of neutering on hormonal concentrations and energy requirements in male and female cats Highlights:
•   Caloric requirements of female cats decreased
•   Neutering led to hyperleptinemia in male cats
•   Fatty acid uptake became resistant to insulin
Responses to neutering differed between sexes
Margarethe Hoenig, Duncan C. Ferguson
Am J Vet Res 2002;63:634-639. May 2002.
 
Effects of dietary fat and energy on body weight and composition after gonadectomy in cats Highlights:
•   Low-, high-fat diets fed to neutered, intact cats
•   Neutered cats gained more body fat, weight
•   Percentage gain in body weight greater in females
Feed a restricted, low-fat diet to prevent obesity
Patrick G. Nguyen, Henri J. Dumon, Brigitte S. Siliart, Lucile J. Martin, Renaud Sergheraert, Vincent C. Biourge
Am J Vet Res 2004;65:1708-1713. December 2004.
 
 

Anesthesia

 
 
Use of the anesthetic combination of tiletamine, zolazepam, ketamine, and xylazine for neutering feral cats Highlights:
•   Drug combination given IM to 7,502 feral cats
•   79.5% required only a single dose
•   0.35% overall mortality rate found
Ease of use, low mortality rate are key benefits
Lindsay S. Williams, Julie K. Levy, Sheilah A. Robertson, Alexis M. Cistola, Lisa A. Centonze
J Am Vet Med Assoc 2002;220:1491-1495. May 15, 2002.
 
Epidural anesthesia with bupivacaine, bupivacaine and fentanyl, or bupivacaine and sufentanil during intravenous administration of propofol for ovariohysterectomy in dogs Highlights:
•   30 female dogs of various breeds studied
•   Higher dosing made epidural feasible for OHE
•   Analgesia highest in sufentanil group
With higher dosing, all 3 techniques sufficient
Tatiana F. Almeida, Denise T. Fantoni, Sandra Mastrocinque, Angelica C. Tatarunas, Viviane H. Imagawa
J Am Vet Med Assoc 2007;230:45-51. January 1, 2007.
 
Cardiorespiratory responses and plasma cortisol concentrations in dogs treated with medetomidine before undergoing ovariohysterectomy Highlights:
•   Use of medetomidine reduced anesthetic needed
•   Analgesia lasted for 60 minutes after extubation
•   Pain-related distress may occur 5 hours after OHE
Give supplemental analgesic at time of extubation
Jeff C. H. Ko, Ronald E. Mandsager, Douglas N. Lange, Steven M. Fox
J Am Vet Med Assoc 2000;217:509-514. August 15, 2000.
 
Results of 24-hour ambulatory electrocardiography in dogs undergoing ovariohysterectomy following premedication with medetomidine or acepromazine Highlights:
•   Lower minimum heart rate with medetomidine
•   Despite low heart rate, response to stimuli normal
•   Similar prevalences of cardiac disturbances found
Heart rate effects seen up to 6 hours after surgery
Dr. Misse A-M. Väisänen, Outi M. Vainio, Marja R. Raekallio, Heikki Hietanen, Heikki V. Huikuri
J Am Vet Med Assoc 2005;226:738-745. March 1, 2005.
 
 

Pain management

 
 
Behavioral alterations and severity of pain in cats recovering at home following elective ovariohysterectomy or castration Highlights:
•   Owners observed cats postoperatively for 3 days
•   Pain, changes in behavior were reported
•   Social behavior changes seen 3 days after surgery
Findings emphasize owner concerns about pain
Misse A-M. Väisänen, Suvi K. Tuomikoski, Outi M. Vainio
J Am Vet Med Assoc 2007;231:236-242. July 15, 2007.
 
Effects of preoperative administration of ketoprofen on anesthetic requirements and signs of postoperative pain in dogs undergoing elective ovariohysterectomy Highlights:
•   Postoperative activity levels higher with ketoprofen
•   Numerical pain scores same as in control group
•   Ketoprofen did not reduce anesthetic needed
Behavior score may be better indicator of pain
Kip A. Lemke, Caroline L. Runyon, Barbara S. Horney
J Am Vet Med Assoc 2002;221:1268-1275. November 1, 2002.
 
Effects of preoperative administration of ketoprofen on whole blood platelet aggregation, buccal mucosal bleeding time, and hematologic indices in dogs undergoing elective ovariohysterectomy Highlights:
•   Platelet aggregation decreased with ketoprofen
•   Mucosal bleeding time same as for control group
•   No increase in hemorrhage during or after surgery
Mucosal bleeding normal despite platelet effects
Kip A. Lemke, Caroline L. Runyon, Barbara S. Horney
J Am Vet Med Assoc 2002;220:1818-1822. June 15, 2002.
 
Postoperative hypoxemia and hypercarbia in healthy dogs undergoing routine ovariohysterectomy or castration and receiving butorphanol or hydromorphone for analgesia Highlights:
•   Increases in PaCO2 seen with hydromorphone
•   Either drug may cause decreases in PaO2
•   Mean values remained within reference limits

Postanesthetic O2 generally not needed
Vicki L. Campbell, Kenneth J. Drobatz, Sandra Z. Perkowski
J Am Vet Med Assoc 2003;222:330?336. February 1, 2003.
 
Comparison of oral and subcutaneous administration of buprenorphine and meloxicam for preemptive analgesia in cats undergoing ovariohysterectomy Highlights:
•   No difference in visual pain scores among groups
•   More pain on palpation with buprenorphine PO
•   No significant differences in sedation scores
Preoperative use of meloxicam is recommended
Adam D. Gassel, Karen M. Tobias, Christine M. Egger, Barton W. Rohrbach
J Am Vet Med Assoc 2005;227:1937-1944). December 15, 2005.
 
 

Surgical risks

 
 
Ovarian remnant syndrome in dogs and cats: 21 cases (2000-2007) Highlights:
•   19 dogs, 2 cats identifed from 2000-2007 records
•   Clinical signs associated with proestrus, estrus
•   All residual tissues found near ovarian pedicles
Surgical removal of ovarian tissue resolved signs
Rebecca L. Ball, Stephen J. Birchard, Lauren R. May, Walter R. Threlfall, Gregory S. Young
J Am Vet Med Assoc 2010;236:548-553. March 1, 2010.
 
Major abdominal evisceration injuries in dogs and cats: 12 cases (1998-2008) Highlights:
•   8 dogs, 4 cats with abdominal evisceration studied
•   Trauma, postsurgical dehiscence were causes
•   Postsurgical cases followed ovariohysterectomy
Prompt intervention can lead to favorable outcome
Sara B. Gower, Chick W. Weisse, Dorothy C. Brown
J Am Vet Med Assoc 2009;234:1566-1572. June 15, 2009.
 
 

Alternative methods

 
 
Duration, complications, stress, and pain of open ovariohysterectomy versus a simple method of laparoscopic-assisted ovariohysterectomy in dogs Highlights:
•   Each method performed on 10 dogs
•   Laparoscopic-assisted group less painful
•   Glucose, cortisol higher in open-method group
Laparoscopic-assisted method less stressful
Chad M. Devitt, Ray E. Cox, Jim J. Hailey
J Am Vet Med Assoc 2005;227:921-927. September 15, 2005.
 
Use of laparoscopic-assisted cryptorchidectomy in dogs and cats Highlights:
•   10 dogs, 3 cats included in study
•   Laparoscopy avoids disadvantages of laparotomy
•   Exteriorizing of the testicle simplifies ligation
Technique minimally invasive, offers good visibility
Nathan A. Miller, Stephen J. Van Lue, Clarence A. Rawlings
J Am Vet Med Assoc 2004;227:921-927. March 15, 2004.
 
Comparison of intratesticular injection of zinc gluconate versus surgical castration to sterilize male dogs Highlights:
•   161 privately owned dogs neutered
•   103 dogs treated with zinc gluconate
•   Necrotizing injection-site reactions seen in 4 dogs
Need strategies to avoid adverse reactions
Julie K. Levy, P. Cynda Crawford, Leslie D. Appel, Emma L. Clifford
Am J Vet Res 2008;69:140-143. January 2008.
 
 

Additional resources

 
 
The Association of Shelter Veterinarians veterinary medical care guidelines for spay-neuter programs
Andrea L. Looney, Mark W. Bohling, Philip A. Bushby, Lisa M. Howe, Brenda Griffin, Julie K. Levy, Susan M. Eddlestone, James R. Weedon, Leslie D. Appel, Y. Karla Rigdon-Brestle, Nancy J. Ferguson, David J. Sweeney, Kathy A. Tyson, Adriana H. Voors, Sara C. White, Christine L. Wilford, Kelly A. Farrell, Ellen P. Jefferson, Michael R. Moyer, Sandra P. Newbury, Melissa A. Saxton, Janet M. Scarlett
JAVMA, Vol 233, No. 1, July 1, 2008.
View article   (PDF, 354 KB)
 
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