New research led by academics at the University of Bristol's School of Veterinary Sciences has shown that 85% of pet cats are not neutered by the recommended age of four months, possibly due to cat owners needing better information about when to neuter their cat.

In 2006, the recommended neutering age of pet cats reduced from six to four months of age. The study assessed the proportion of cats neutered at these ages. Data was obtained from owner-completed questionnaires at recruitment, when kittens were aged eight to 16-weeks, and six and a half to seven months of age. Demographic and lifestyle factors were also assessed for potential association with neuter status.

The researchers found that of the 751 cats in the study, 14.1% and 73.5% had been neutered at or before four and six months of age, respectively. Cats were significantly more likely to be neutered at four months if their owners had always intended to have their cat neutered by this age. They were also significantly more likely to be neutered at four months if they were microchipped or from households in deprived regions.

The likelihood of being neutered, compared with unneutered, at six months of age was significantly increased for cats that were insured, obtained from an animal welfare organisation, given their second vaccination, from a household with an annual income of over £10,000 and owned by people intending to have their cat neutered by this age.

Dr Jane Murray, Cats Protection Research Fellow in Feline Epidemiology, said: "Neutering is recommended as an effective way of reducing the number of unwanted cats in the UK. Our study found that age of neutering was associated with the age of intended neutering.  Cats can reach puberty at four to five months of age therefore, it is important that owners are aware of the recommended age of neutering at four months, to reduce the number of unplanned pregnancies that occur."

The study suggests that while neutering rates were high at six months of age, they were low at four months of age, and that further work is required to publicise the recommended neutering age of four months to cat owners.

Paper: The neuter status of cats at four and six months of age is strongly associated with the owners' intended age of neutering, C. P. Welsh, T. J. Gruffydd-Jones and J. K. Murray, Veterinary Record published online April 19, 2013.

PS: Whilst you're here, take a moment to see our latest job opportunities for vets.