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Research Library

Results of integrated TNR/RTF programs on shelter intake and killing


“Integrated Return-To-Field and Targeted Trap-Neuter-Vaccinate-Return Programs Result in Reductions of Feline Intake and Euthanasia at Six Municipal Animal Shelters,” published in Frontiers of Veterinary Science, 2019. Complete article available (open access) online here.


Return-to-field (RTF) is a relatively new twist on trap-neuter-return (TNR). Cats brought to shelters (either by residents or animal control officers) are sterilized and vaccinated, then returned to their original location.

This study presents the results of six three-year, shelter-based programs integrating RTF with targeted TNR efforts. In total, nearly 73,000 cats were treated though these programs, resulting in dramatic reductions in feline intake and shelter killing, and equally dramatic increases in live-release rate (i.e., live outcomes divided by intake).

Key points

This study [1] builds on the work of a previous study [2] documenting reductions in feline intake and shelter killing upon the implementation of an integrated RTF and targeted TNR program. Across the six programs, researchers documented median reductions of 32% in feline intake and 83% in shelter killing, with a median increase of 53% in live-release rate.

Researchers documented median reductions of 32% in feline intake and 83% in shelter killing.

More than 8 in 10 cats (83%) treated through these programs were returned to their original location (after having been sterilized and vaccinated), while another 15% were adopted (either directly through the shelter or via local rescue groups). Roughly 0.6% were returned to their owners, 0.5% were euthanized due to serious health concerns, 0.3% were relocated, and 0.2% died during or following surgery.

Although such studies cannot directly assess possible population reductions in a shelter’s service area, reductions in the intake of young kittens offer an interesting proxy metric; the six shelters contributing to this study documented median reductions of 40% in kitten intake (i.e., cats under 6 months of age) and 41% in the intake of newborn kittens (i.e., under 8 weeks of age). This suggests that the programs were having population-level impacts in their respective communities.

Results of this study suggest that cats entering RTF and TNR programs are generally healthy; only 0.5% were euthanized due to serious health concerns, and the number of cats brought to the shelter dead (e.g., hit by car) typically decreased following the implementation of integrated RTF/TNR programs.




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