Factors affecting hair cortisol concentration in privately owned intact cats

Understanding the factors affecting long-term stress in domestic cats is essential for welfare assessment, and hair cortisol concentration has been proposed as a promising biomarker for this purpose. This study investigated hair cortisol concentrations in intact, privately owned cats (Felis silvestris catus), with emphasis on physical and behavioral factors, as well as housing conditions. Hair samples were collected from 103 cats (40 males, 63 females) during routine preparation of the surgical field under general anesthesia prior to neutering. In females, samples were collected from the abdominal region along the linea alba, whereas in males, hair was taken from the area surrounding the scrotum. Information about the cats was collected from their owners, who completed a brief questionnaire covering the cats' basic characteristics and lifestyle. Cortisol extraction from hair and subsequent quantification were performed using a commercially available ELISA kit. The overall mean hair cortisol concentration detected in the 103 cats was 9.99 pg./mg. Age, breed, coat type, coat color, and season of hair collection had no significant effect on cats' hair cortisol levels (p > 0.05). However, sex was found to significantly influence hair cortisol concentration, with male cats exhibiting higher cortisol levels. Environmental and behavioral factors in cats were not found to significantly affect hair cortisol concentrations. These findings suggest that long-term cortisol levels in intact, privately owned cats may be influenced more by inherent individual traits than by environmental or behavioral factors, indicating a need for further research in this area.