Three Things to Know
Researchers examined the factors influencing dog euthanasia across five U.S. states, finding that phenotype was a more reliable predictor of euthanasia than the length of stay at the shelter.
They found that older dogs, larger dogs, and brachycephalic dogs were at the highest risk of euthanasia. Coat length and color, however, were not significant factors.
By identifying these factors, researchers hope to empower shelter staff to make more informed and unbiased decisions about dog euthanasia.
The Full Picture
Public awareness of dog euthanasia in U.S. animal shelters has increased, leading to a significant decline in euthanasia rates. While the number of dogs euthanized annually has dropped from a high of 17 million in 1988 to less than one million today, shelters still euthanize dogs deemed unlikely to be rehomed.
Research has shown that several factors can influence a dog’s chances of being euthanized, including age, size, coat color, and perceived attractiveness. Dark-coated and less attractive dogs, for instance, often face higher euthanasia rates.
However, previous studies on these factors have been limited by factors such as sample size and geographic scope. To address these limitations, this study, titled “Factors Associated with Shelter Dog Euthanasia versus Live Release by Adoption or Transfer in the United States,” examines the factors influencing shelter dog euthanasia across a representative sample from five U.S. states.
Study Methods
This study analyzed data from 17 municipally funded animal shelters across five U.S. states: Mississippi, Pennsylvania, Michigan, Colorado, and Oklahoma. These shelters, also selected in a previous study on factors associated with adoption, were chosen based on their open-admission policies and electronic record-keeping systems. Data on 19,514 dogs with potential for adoption or transfer were collected. Dogs euthanized at the owner’s request, returned to their owner, deceased on arrival, or with a zero-day length of stay were excluded from the analysis.
Researchers collected the following information about each dog to examine the factors influencing adoption, transfer, and euthanasia outcomes:
- Phenotypic Traits: Estimated breed characteristics, including adult size, coat length, and skull shape (brachycephalic, dolichocephalic, mesocephalic), were inferred from public adoption website listings.
- Blockhead Classification: Dogs were categorized as blockheads if they belonged to breeds like pit bulls, Staffordshire terriers, boxers, or mastiffs, known for their square-shaped heads.
- Body Weight Categories: Dogs were grouped by expected adult weight into small, medium, large, and giant (giant category was merged into large due to low representation).
- Coat Length and Color: Coat length was classified as short or long (medium coat length was grouped with long). Coat colors were categorized into eight groups: black, brown, red, gray, white, tan, yellow, and blue.
- Age Groups: Dogs were categorized by age as puppies (≤6 months), adults (>6 months to <8 years), or seniors (≥8 years).
- Geographical Regions: Shelters were grouped by region as southern (Mississippi, Oklahoma), northern (Michigan, Pennsylvania), or western (Colorado).
By analyzing these factors, the study aimed to identify the specific characteristics that influence a dog’s likelihood of being adopted, transferred, or euthanized.
Study Results
This study found that 14% of shelter dogs with the potential for adoption or transfer were euthanized. The median and average length of stay (LOS) for euthanized dogs was 6 and 9 days, respectively. Several factors significantly influenced the likelihood of euthanasia:
- Age: Puppies were less likely to be euthanized than adults or seniors. Adults were also less likely to be euthanized than seniors.
- Skull Type: Brachycephalic dogs (with short, flat faces) were more likely to be euthanized than mesocephalic or dolichocephalic dogs (with normal or long, narrow faces).
- Size: Large dogs were consistently at greater risk of euthanasia compared to small dogs across all regions. In the southern U.S., medium-sized dogs also faced increased risks compared to small dogs.
- Region: The interaction between region and size revealed that large dogs were at greater risk of euthanasia compared to small dogs across all regions. In the southern U.S., medium-sized dogs also faced increased risks compared to small dogs.
Puppies were more likely to be adopted or transferred compared to adults and seniors, likely due to their higher appeal to adopters and lower likelihood of health or behavioral issues. Seniors, on the other hand, faced greater euthanasia risks, possibly due to health concerns, lower adoption rates, and longer length of stay.
Conclusion
The study concluded that skull type, size, regional location, and age group are all associated with the likelihood of shelter dog euthanasia. These findings likely reflect a combination of adopter preferences and shelter staff perceptions regarding the adoptability of certain dogs. By identifying these factors, the study provides valuable insights that can help shelter staff make informed, evidence-based decisions about the outcomes of dogs in their care.
Miscellaneous
Data From Study:
Shelter Dogs > More Humane Future > Minimizing Euthanasia
Year of Publication:
2021
External Link:
Cain CJ, Woodruff KA, Smith DR. Factors Associated with Shelter Dog Euthanasia versus Live Release by Adoption or Transfer in the United States. Animals. 2021; 11(4):927. https://doi.org/10.3390/ani11040927