Variability of Heart Rate in Primitive Horses and Their Relatives as an Indicator of Stress Level, Behavioural Conduct Towards Humans and Adaptation to Living in Wild

The aim of the study was to evaluate the possibility of using heart rate (HR) as a metric parameter that can be used for the characterisation of behaviour of primitive horses and their relatives, related to reactions to the stress resulting from the contact with humans and adaptation to living in various conditions, including natural environment. This characterisation served the authors to expand the knowledge of such behaviour of primitive horses, and to assess the impact of the environmental and genetic factors. Studies were conducted in three populations of horses: two herds of Polish Konik and one herd of Biłgoraj horses. The studies were performed between 1993 and 2010. They concerned the behaviour of horses during grooming - breeding procedures (hooves clearing, body measurements) performed cyclically and the daily observations when HR was monitored continuously. HR results for the respective age categories, during particular grooming - breeding procedures and reserve observations indicate that Polish Konik horses, closely related to the primitive Tarpan breed, are genetically better adapted to living in conditions similar to the natural (reserve) than the Biłgoraj horses. They show less stress symptoms, which are evidenced by HR values noted during inhabiting the natural environment.