Changes in numeric characteristics of variable pulse diagrams resulting from acute stress in cow-heifers

The aim of the work is to study the increase of adaptive capabilities in cow-heifers under acute stress. We divided the test animals into 2 groups (control and experimental) according to the strain index readings and initial vegetative tonus - normotony. The experimental group was treated with the amber acid metabolite. The stress effect on the cardio vascular system of the test cows was analyzed with the use of R. М. Bayevskiy method. The sinus cardiac rhythm with later analysis of its structure was registered. A comparative analysis of numeric characteristics of variable pulse diagrams reflecting conditions of stressed cows treated with the amber acid metabolite and cows that were not given the substance was carried out. The use of the amber acid metabolite in the experimental group of cows reduced their pulse rate frequency and led to the decrease of functional backup. The control group cows revealed an increase in the number of cardio intervals, which speaks of the enhancement of non-respiratory component of sinus arrhythmia. A decrease of the index readings in the cows from control group is a manifestation of the non-respiratory component domination in the cardiac rhythm, which in tern is determined by the activity of subcortical centers. This index decrease in the experimental group of cows speaks about a potential tonus of the parasympathetic nervous system and domination of respiratory changes in the cardiac rhythm. Thus, the amber acid metabolite usage helps to preserve the optimal functioning level of the vegetative nervous system. The use of the substance is instrumental in the improvement of adaptive capabilities in cows under acute stress.