Saint Francis Service Dogs (SFSD) of Roanoke, VA (USA) trains dogs as service animals for people with autism, multiple sclerosis, brain injury, and many other conditions. Organizations like SFSD must carefully consider when to neuter their dogs to give them the best chance at successfully completing lengthy and expensive training. The objective of this retrospective cohort study was to determine if there are differences in training success rates or incidence of health or behavior problems between dogs neutered earlier in life compared to those neutered later in life.
A group of 245 dogs, primarily Labrador retrievers and Golden retrievers, were analyzed; seventy-eight females and 167 males were included. Data on the dogs, including birth date, sex, neuter date, year of dismissal or successful completion of training, and reason for dismissal (where applicable), was collected from records at the SFSD facility. Ranked age at neuter was compared between dogs who successfully completed training and dogs who were dismissed from training; then, age-at-neuter groups were generated and tested to look for nonlinear patterns.
Results: Dogs who were dismissed for orthopedic problems had a lower median age at neuter than dogs who successfully completed training (Mann-Whitney U, p = 0.03); this was also true when analyzing only the female dogs (Wilcoxon, p = 0.01). Dogs who were neutered between 7 months and 11 months of age were dismissed due to behavioral problems at a significantly lower rate than dogs who were neutered at an older or younger age (Fisher’s exact test, p = 0.04). Among females, dogs neutered prior to 7 months of age were significantly less likely to successfully complete training compared to dogs neutered between 7 months and 11 months of age and were also less likely to successfully complete training than dogs neutered at over 11 months of age (Fisher’s exact test, p = 0.02).
This study suggests that there is a relationship between dogs’ age at neuter and their ability to successfully complete service dog training, and that this may be especially true of female dogs.