March 28, 2018

Audience: Executive Leadership, Shelter/Rescue Staff & Volunteers, Veterinary Team

Organization: The Center for Animals and Public Policy, Cummings School of Veterinary Medicine, Tufts University and Best Friends Animal Society
Investigator(s): Gary Patronek, Abbi Crowe
Grant Amount: n/a
Project Type: Phase 1
Project Status: Research Complete

Project Summary

This research project from The Center for Animals and Public Policy, Cummings School of Veterinary Medicine at Tufts University, sought to better understand factors contributing to live release (e.g., rehoming). Results showed that temporary placement of dogs, who were either not immediately eligible or not strong candidates for adoption due to reasons such as age or health, increased the odds of live release after subsequent return to the shelter. Over a fifth (21%) of dogs originally brought to the shelter for owner-requested euthanasia were determined to be potentially savable and ultimately rehomed.


To better understanding of factors contributing to live release at a large, open-admission, municipal shelter


In this cross-sectional, exploratory, non-interventional study, data were analyzed for all dogs (n=21,409) admitted over a two-year period for the primary purpose of rehoming at a high-volume, open-intake municipal shelter performing animal control (the Pima Animal Care Center in Tucson, Arizona). Characteristics associated with live release and length of stay were identified by downloading all records from the shelter's database from January 1, 2015 through December 31, 2016, and analysis via statistical software. Variables in the original dataset included sex, estimated age, weight, sterilization status, estimated size, intake date, outcome date, intake type (i.e., owner surrender, stray, return from adoption, and return from foster care), outcome type (i.e., adoption, sent to foster care, transferred to rescue, died, and euthanized), and primary color. Foster care was defined as placement in an interim home in the community for purposes of medical or behavioral rehabilitation prior to being returned to the shelter for permanent adoption.


  • Live release was >88%.
  • A total of 1510 (7.1%) dogs interacted with the foster care system, 98.9% of whom had live release.
  • Foster care increased the odds of live release by about five-fold for all dogs and by >20-fold for adult dogs compared to first-time owner-surrendered dogs.
  • Dogs returned from foster care had a 70% reduction in health concerns, as judged by intake staff, compared with dogs sent to foster.
  • The rescue network utilized by this shelter (PACC) was estimated as having largely reduced in-shelter care needs (by 13,409 animal care-days over two years).
  • Dogs returned from adoption also had increased odds of live release.
  • Nearly a third (30%) of dogs originally brought in by owners for euthanasia (ORE) were determined to be potentially savable, and a fifth of the original group (21%) were ultimately placed.
  • Dogs with a physical appearances similar to stigmatized dog breeds had a live release rate of 80.5% compared with 91.7% for dogs not in that category. They were also less likely to be placed within a week of intake.
  • Less than 4% of dogs presented with behavioral concerns at intake.


These results from two years of data demonstrated it is possible to save the lives of the majority of dogs eligible for rehoming in a large, municipal, open-admission shelter. Furthermore, it is found that some dogs initially brought by their owners to PACC for euthanasia could in fact be rehomed. The foster program at PACC improves the odds of live release, especially for adult dogs. Dogs returned from adoption have a live-release advantage as well, which suggests that the temporary experience in a home is not detrimental and may have facilitated the likelihood of live release after return, akin to a foster situation. Although these results are encouraging, it is not possible to infer establish causal relationships from associations identified in a cross-sectional study, and the foster program is examined only as an intake type, not as a formal intervention studied prospectively. It remains to be determined whether similar results are achievable by a much broader group of animal shelters in the US.