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UDC 636.7:612.8:591.1:612.018

Received: April 27, 2026

Revised: May 1, 2026

Published: May 29, 2026

This is an Open Access article under the CC BY-NC-ND 4.0 license

 

The problem of stress resistance in dogs is highly relevant in modern veterinary medicine, as stressors significantly affect the physiological state, behavior, and adaptive capacity of animals under various housing and use conditions. The autonomic nervous system plays a key role in shaping the stress response by determining the intensity and duration of neuroendocrine reactions. The aim of this study was to determine the tonus-dependent hormonal response of dogs to an acute acoustic stressor and to evaluate the possibilities for its correction using nano-compounds of trace elements. The study was conducted on 30 German Shepherd dogs with different types of vegetative tone. Acute stress was induced using the open field test with thunder sound playback, and organism reactivity was assessed by measuring plasma cortisol levels before and after stress exposure. The results showed that dogs with sympathicotonia exhibited the highest baseline cortisol levels and the greatest amplitude of the hormonal response with delayed recovery, indicating increased reactivity and reduced adaptive reserves. Dogs with a normotonic type of autonomic regulation demonstrated a more balanced and controlled cortisol dynamics, whereas vagotonic dogs showed a less intense acute response accompanied by high individual variability. The use of nano-compounds of trace elements was associated with a tendency toward a reduced amplitude of the cortisol response to stress, particularly in dogs with sympathicotonic autonomic profiles, suggesting their potential as a promising means of modulating stress reactivity. The obtained results confirm the decisive role of vegetative tone type in shaping the neuroendocrine stress response in dogs and may be applied to predict individual stress resistance and to develop approaches for its correction in veterinary practice.

 

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