Globally, large populations of companion animals are relinquished each year. The purpose of this scoping review was to identify all published research investigating companion-animal relinquishment to map out and evaluate research gaps, needs, and opportunities. A comprehensive search strategy was implemented in 4 online databases, identified citations were screened, and relevant articles were procured and characterized. From 6,848 unique citations identified, 192 were confirmed relevant, including 115 primary-research articles and 77 reviews and commentaries. The majority of these articles originated from the United States (131; 68.2%); 74 (38.5%) of them have been published since 2006. Among the primary-research articles, 84 (73.0%) investigated reasons for companion-animal relinquishment. The most commonly studied reasons were aggressive companion-animal behaviors (49; 58.3%); moving, rental, or housing issues (45; 53.6%); and caretaker personal issues (42; 50.0%). Only 17 primary-research articles investigated interventions to prevent companion-animal relinquishment. The quantity of research into reasons for relinquishment highlights an opportunity for future knowledge-synthesis activities in this area, including systematic review and meta-analysis. In comparison, the limited research into interventions identifies a priority for new research.
Keywords: companion animals; companion-animal relinquishment; companion-animal surrender; scoping review.