A Prospective Study Investigating the Health Outcomes of Bitches Neutered Prepubertally or Post-Pubertally

There are scant studies of associations between the pubertal status at neutering and subsequent health outcomes of female dogs. This study examined health data for Labrador and Golden Retriever crossbreed bitches neutered by ovariohysterectomy either before (PrePN, n = 155) or after (PostPN, n = 151) puberty using a prospective study design. Data were extracted from an electronic database containing detailed health records for all bitches. Cruciate ligament disease occurred in significantly more PrePN (n = 11) than PostPN bitches (n = 1; Yates Chi-square = 6.784, D.F. = 1, p = 0.009), and PrePN bitches had lower probabilities of remaining free from osteoarthritis (χ² = 5.777, D.F. = 1, p = 0.016). Additionally, PrePN bitches were diagnosed with atopic dermatitis (PrePN: 3.9 ± 0.6 years, PostPN: 1.6 ± 0.3 years; Mann-Whitney U test = 90.5, p = 0.008) and perivulval dermatitis (PrePN: 4.7 ± 0.9 years, PostPN: 0.8 ± 0.1 years; Mann-Whitney U test = 40.0, p = 0.002) at significantly older ages and had lower probabilities of remaining free from otitis externa (χ² = 7.090, D.F. = 1, p = 0.008). No associations were identified between the pubertal status at neutering and the incidence of any urogenital disease, including urinary incontinence, which was diagnosed in a small number of bitches (one PrePN and six PostPN). The results suggest that prepubertal neutering may have a detrimental effect on some future musculoskeletal and immune diseases in bitches of these crossbreeds, providing important information to support neutering policies and to help maintain optimal dog welfare.