Age of sexual maturity and factors associated with neutering dogs in the UK and the Republic of Ireland

Background Surgical neutering of dogs is common, however the average age that dogs reach sexual maturity, are neutered, and dog owners’ attitudes to neutering in the UK and the Republic of Ireland have not been explored in a longitudinal study. Methods Owner‐reported data on the timing of the first oestrus, timing of neutering and the reasons given for neutering dogs by 12 and 15 months of age were summarised. Factors associated with neutering at 15 months and factors associated with intention to neuter were quantified using multivariable logistic regression. Results At 15 months of age, 90.0% (n = 207/230) of unneutered females had had their first oestrus. By 7, 9, 12 and 15 months of age, 22.1% (n = 131/593), 32.2% (197/593), 45.4% (n = 269/593) and 59.9% (n = 352/593) of dogs were neutered, respectively. Breed purity, dog's source, owners’ intentions to neuter and the number of dogs in the household were associated with neuter status at age 15 months. Dog's sex, Kennel Club registration, dog's source, dogs intended to be working dogs and previous dog ownership were associated with intentions to neuter. Preventing puppies was the most common reason for neutering. Conclusion Understanding factors that shape owners’ intentions to neuter can inform owner‐vet discussions regarding whether to neuter a dog and the optimal age for doing so.