So we went with a study that looks at the influence of experimenter sex on mouse behavior and their response to ketamine: https://www.nature.com/articles/s41593-022-01146-x
It seems mice show aversion towards males & exposure to male scents activates the corticotropin-releasing factor neurons in the entorhinal cortex. Plus, this pathway must be activated before ketamine administration, or ketamine won’t produce its antidepressant effects.
https://neurofrontiers.blog/why-men-stress-mice/