Allostatic Load Scoring for Understanding Stressors and Predicting Success in Guide Dogs: A Pilot Study | HABRI

Allostatic Load Scoring for Understanding Stressors and Predicting Success in Guide Dogs: A Pilot Study

Principal Investigator

Barbara A. Wolfe, DVM, PhD, DACZM (Colorado State University)


Chronic stress is associated with increased morbidity and mortality in all vertebrates. Our ability to quantify chronic stress is central to our understanding of how stress affects health and physical functioning, and to our development and assessment of strategies to intervene and ameliorate these effects. Allostatic load (AL)is the ‘wear and tear’ on the body due to chronic or frequent stressors, or inability to adapt to stressors. The development of a test to measure AL in humans (the allostatic load index, ALI) has led the way for us to identify the causes and health impacts of chronic stress.

This research has the potential to result in a quantitative test of accumulated stress in dogs. If successful, this tool may be able to:

  • a) predict resilience and success in potential working dogs;
  • b) identify stress levels potentially leading to mental and physical health declines, allowing for amelioration; and
  • c) augment current diagnostics for evaluating health and well-being in our canine companions.


  • Objective 1: To validate the ALI for the domestic dog as a measure of chronic stress based on biomarkers proven successful in humans and NHP by measuring its association with first-year-of -life events and lifestyle factors in Labrador retrievers raised and trained for guide service.
  • Objective 2: To evaluate the value of the ALI for predicting success in guide dogs through its association with temperament and behavior scores, suitability for training, and training success.



  • Hypothesis 1: The null hypothesis is that there is no association between ALI and events/lifestyle factors considered to be chronic psychosocial stressors in dogs.
  • Hypothesis 02: The null hypothesis is that, in this population of Labrador retrievers, there is no association between ALI and temperament, behavior or training success.


Our study will utilize 40 Labrador retrievers bred and raised to be trained as guide dogs (treatment), and 5 Labrador retrievers raised as pets only (controls). We will categorize and quantify lifestyle factors, behavior scores, and early life events documented for each dog in its first year of life, and compare them to AL scores at 12-14 months of age, when assessment of suitability for training occurs in the treatment group. AL will also be compared to success measures during training and after training, for those dogs that are rejected or graduate, respectively.

Expected Results

We expect that AL will be positively associated with early life stressors and negatively associated resilience and success in training in this group of Labrador retrievers. We expect no difference in AL between pet dogs and dogs bred and raised to be guide dogs in the first year of life.