Pre-pubertal desexing of dogs and cats
Policy type: Policy
Date ratified: 4 May 2015
The New Zealand Veterinary Association (NZVA) supports pre-pubertal desexing of dogs and cats from eight weeks of age, provided each animal is individually assessed for suitability prior to surgery. Six months is the traditional age for this surgery, but desexing at an earlier age is also acceptable, especially for breeders, shelters and other humane organisations. The benefits of early desexing include improved population control, quicker surgical procedure, less trauma and stress for the animal and reduced recovery times.
The control of overpopulation in dogs and cats is a problem well recognised in New Zealand and overseas. There are still critical numbers of animals admitted to shelters worldwide, and many are euthanased. Despite various voucher schemes, contracts, deposits and forms of follow-up, compliance with desexing requirements for animals after adoption from a shelter is poor. Desexing prior to adoption is the best way to ensure these animals don’t reproduce. Prepubertal desexing also allows breeders to spay and neuter animals prior to rehoming. This ensures pet quality animals can be re-homed earlier, thus facilitating socialisation and training, while preventing animals with potential heritable defects from reproducing.
Puberty is defined as “the condition of being or the period of becoming first capable of reproducing sexually.” The age at which puberty is reached varies. In female dogs it is as early as six months, male dogs as early as 4-5 months; in female and male cats as early as four months. At six months of age, the traditional age for desexing, dogs and cats may or may not be prepubertal.
Pre-pubertal desexing – considerations
There is no association between age at desexing and frequency of occurrence of most behavioural and medical conditions. There may be some physical differences. Surgery is easier and quicker in younger animals as they have less fat and blood vessels are smaller. When dogs and cats are desexed prior to 14 weeks there are some anaesthetic and physiological considerations.
There is no difference in food intake or weight gain between dogs and cats desexed before puberty and those desexed after puberty. Metabolism has been demonstrated to be decreased in desexed cats regardless of age at desexing. In one study, earlier desexing of dogs was correlated with decreased obesity. Obesity is a multifactorial disease of which desexing may only play a part.
Desexing before puberty may confer many positive behavioural benefits, such as reduction in urine spraying, sexual behaviour, fighting and roaming.
Desexing female dogs prior to their first heat provides a dramatically reduced risk of mammary tumour development, and avoids the possibility of pyometra.
Some studies show that there is an increased risk of oestrogen-responsive urinary incontinence with decreasing age of desexing in female dogs. The risks and benefits of the early procedure should be considered and where population control is not the primary issue, it may be advisable to delay desexing of female dogs until they are at least 3–4 months of age. In one study, the incidence of cystitis has been shown to be increased in female dogs desexed prior to 5.5 months of age, but no episodes of the condition occurred more than twice.
Secondary sex characteristics
External genitalia may be smaller in male and female dogs and cats desexed before puberty. Female dogs may have the appearance of a juvenile “tucked-up” vulva. The timing of desexing has not been shown to affect urethral diameter in cats. In bitches, waiting until after first oestrus to spay has not been shown to decrease the incidence of perivulvar dermatitis.
These procedures may be performed safely in prepubertal animals, provided that appropriate attention is given to anaesthetic and surgical techniques. The Companion Animal Society of the NZVA has developed material to inform veterinarians of current anaesthetic/surgical techniques available for early desexing of dogs and cats. This information is available in the members’ zone of the NZVA website and from the NZVA office on request.
Spain C, Scarlett JM & Houpt KA. Long term risks and benefits of early age
gonadectomy in cats, Journal of the American Veterinary Medical Association 224:372-379, 2004
Spain C, Scarlett JM & Houpt KA. Long term risks and benefits of early age gonadectomy in dogs. Journal of the American Veterinary Medical Association 224:380-387, 2004
Walsh V & Worth A. Early age neutering. Proc NZVA Companion Animal Society Conference, 2008
Worth A. Early Desexing – Benign or Problematic? World Small Animal Veterinary Association World Congress Proceedings, 2013