Efeito da acupuntura nas respostas de estresse em equinos: testes laboratorial e a campo

Abstract

Acupuncture is an ancient technique of Chinese traditional medicine used in the treatment and prevention of diseases, and aims to help the body return to its balance state, by inserting metal needles at specific points in the skin. Under stress conditions, the body acts through the activation and deactivation mechanisms to restore and maintain homeostasis. The repeated exposure or the prolonged and exaggerated reaction to stress are associated with the onset of various diseases. Thus, it is essential to use strategies that can prevent or minimize the deleterious effects of stress. The heart rate variability (HRV) and the increased serum cortisol respectively reflect the activity of the autonomic nervous system and the hypothalamic-pituitary-adrenal (HPA) systems that are activated acutely in stress situations. The present study aimed to standardize an experimental model of acute stress specific to startle horses and evaluate if acupuncture can alter the stress response through the use of stress models (test start and reprise dressage).The present study aimed to evaluate if acupuncture in Dressage horses can alter the stress responses through the use of a laboratory startle test model (sudden umbrella opening) and a test the field: the dressage. In experiment 1, horses previously divided into groups: G1: control, G2: Acupuncture in non-points; G3: Acupuncture points GV1, H7, GV20 and B52 were tested for startle (an abrupt umbrella opening) and analyzed the HRV (through the use of Polar heart rate monitors heart Equine ™), the serum cortisol and the behavior through the reactivity test. In experiment 2, performance in dressage, serum cortisol and HRV were evaluated in horses previously undergone acupuncture points GV1, H7, GV20 and B52. The startle test caused a significant increase of LF/HF that reflects the increased of balance sympathetic in relation to the parasympathetic and a significant behavioral response, without increase cortisol levels. The acupuncture reduced LF/HF ratio at the activation parasympathetic time and cortisol levels 30 minutes after the stress without changing the reactivity response. The treatment in no points had no effect on the studied parameters. The dressage promoted increased levels of cortisol after 30 minutes. Acupuncture significantly reduced the LF/HF ratio, however it had no effect on cortisol levels and the performance evaluated by the judges and riders. The data analysis shows that the models used were effective in the study of stress responses in horses and may be used in further studies to evaluate strategies anti-stress. Furthermore, we conclude that acupuncture can be considered in beneficial in reducing stress levels in athletic horses, mainly due to its potentiating action of the vagal system.