Study tracks chronic hormone patterns in SAR dog-handler teams

A newly published Animals study is taking a longer view of stress biology in search-and-rescue teams, looking beyond acute mission or exam responses and into chronic endocrine patterns in both dogs and handlers. Published June 22, 2026, “Beyond the Mission: Long-Term Endocrine Dynamics in Search and Rescue Dog-Handler Teams” analyzed hair cortisol and hair testosterone from 60 SAR dogs and their handlers, using hair as a retrospective marker of hormone activity over weeks to months rather than minutes to hours. (mdpi.com)

That’s an important shift in a field where much of the earlier literature has focused on acute stress. A 2020 study involving SAR examinations found that salivary cortisol increased significantly in both dogs and handlers immediately after testing, with especially strong hormone-linked responses in female dog-female handler dyads. Other working-dog research has also documented physiologic strain tied to operational conditions, from certification stress in handlers to temperature changes across deployment-style work cycles. (pmc.ncbi.nlm.nih.gov)

In the new paper, the authors collected dog hair from the interscapular region and human hair from the occipital area, then extracted cortisol and testosterone using methanol-based protocols and quantified them by ELISA. Mean dog hair cortisol was 10.974 pg/mg and mean dog hair testosterone was 3.008 pg/mg. Female dogs had significantly higher cortisol than males, and cortisol showed a tendency to increase with age. Testosterone in dogs did not differ by sex, breed, or castration status. Among handlers, mean hair cortisol was 10.874 pg/mg and mean hair testosterone was 2.925 pg/mg, with no significant sex differences, though handler cortisol varied significantly by the breed of dog they handled. The study also found a negative correlation between dog and handler hair cortisol levels. (mdpi.com)

That last finding stands out because earlier SAR research suggested acute hormonal synchrony under exam stress, while this study points to a more complicated picture over the long term. The difference may reflect biology as much as methodology: saliva captures short-term reactivity, while hair reflects cumulative endocrine output over a longer period. Previous canine hair cortisol work has shown that season, lifestyle, and human interaction can all shape long-term cortisol values, reinforcing that chronic endocrine measures are influenced by more than workload alone. (pmc.ncbi.nlm.nih.gov)

Outside this paper, the broader SAR literature also suggests that welfare and performance are multifactorial. A February 2026 Animals study on SAR success reported that performance was associated with environmental conditions, experience, management factors, and a canine profile marked by higher arousal and reactivity, while also noting potential handler self-report bias. Separately, a 15-year longitudinal study of SAR dogs identified musculoskeletal, integumentary, and gastrointestinal problems as common health issues over time. Taken together, the literature suggests endocrine monitoring may eventually become one piece of a larger health-and-performance framework, rather than a standalone answer. (mdpi.com)

Why it matters: For veterinarians advising working-dog programs, this study supports the idea that chronic stress surveillance can be measured non-invasively, but interpretation will require context. Hair cortisol may be useful for longitudinal monitoring in dogs with heavy training loads, recurrent deployments, behavior concerns, or unexplained performance changes. But the existing evidence also argues against overreading a single value. Sex, age, season, lifestyle, training intensity, and the dog-handler relationship may all affect results, and the new study does not establish that higher or lower hormone values directly predict poor welfare, burnout, or operational success. (mdpi.com)

For clinicians, the practical takeaway is less about adding routine hormone panels tomorrow and more about recognizing chronic stress as a measurable, biologically relevant dimension of working-dog care. In programs that already track body condition, orthopedic health, heat stress, and behavior, hair steroid testing could eventually help build a more complete picture of resilience and recovery, especially if future studies tie endocrine patterns to outcomes that matter in practice. (mdpi.com)

What to watch: The next phase for this research will be validation, specifically whether hair cortisol or testosterone can be linked to deployment exposure, certification outcomes, injury patterns, behavioral strain, or veterinary interventions in SAR teams, and whether standardized reference ranges for working dogs emerge from larger cohorts. (mdpi.com)