The personality of a dog is broadly affected by the composition of the gut

Our story began two years ago when our Biological Solutions teacher—and current mentor—Dan Shay introduced us to another student’s project on the intestinal microbiome. Amaya Martin’s project analyzed the intestinal microbiota of SwimHi and SwimLo rats in order to evaluate the Porsolt Swim Test, finding that their behavioral phenotypes aligned with serotonin producing bacteria. Immediately, Alexis was intrigued by this potential connection between the gut and the brain, and she hoped to continue Amaya’s research the following year. However, obtaining rat stools proved too difficult amidst the pandemic, and our project took a different route: analyzing how the gut microbiome affects personality within canines.

As we began our project two summers ago, we surveyed the existing literature in this field, seeking to understand how the gut-brain axis functions in relation to host health and/or canines as model organisms. We obtained samples from volunteers in our community who were willing to administer the C-BARQ personality questionnaire—and sacrifice their dog’s excrement for the sake of science. Moving forward we had to learn the necessary lab skills to complete our project independently which forced us to grow exponentially as young scientists. Techniques in our playbook grew to include sample quantification, precise aliquoting, and data comprehension as we practiced the workflow from DNA extractions to next-generation sequencing.

At times this proved difficult, working digitally as a partnership. Because of this, we also learned to communicate effectively and use what little time we had in the lab efficiently. With competition deadlines quickly approaching and a backorder on our DNA extraction kit, we had to rush to complete the analysis of our data. Originally, we attempted to use measures of diversity including Shannon’s Index and Pielou’s Evenness, but we ultimately resolved to using a linear regression model to compare personality scores to abundances of various bacterial genera.

This project was submitted at both the Eastern Washington Regional and Washington State Science and Engineering Fairs.

The Impact of the Intestinal Microbiome on Personality in Canines

Introduction

Questions, Hypothesis, and Expected Outcomes

Methods

Results

Personality Link

Barcode Taxonomy & Microbiome Diversity

Conclusions

Senior

North Central High School

Jacob Gannon

Senior

North Central High School

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Acknowledgements

Thank you so much to the following people and organizations who supported our research through their time and resources:​

Dan Shay (Lab Manager)​

Theresa Eggleston (Assistant Lab Manager)​

Principal Steve Fisk​

North Central High School & Spokane Public Schools  ​