Résumé:
"Our study is divided in two parts. The first part is a literature review in which we based on four
mains axis, neural control of organism and behavior, neuroanatomy of brain, social behavior in horses and
cattle and finally physiology of stress. The second part is a practical study . Our experimental work consist
on the dissection of two horse’s and two cattle’s brains, aims to search the presence of macro-anatomic
structural differences, the second part is a measures of plasma Cortisol levels. Blood was sampled via
jugular venipuncture from five horses of Arab barb breeds and three groups of different cattle’s strains, five
animals per group to measure reactions and sensitivity to stress in these two species. We exposed them to
tests in order to create an acute stress. We have found some structural particularities in the brain, mainly in
the vasculature, weight, volume and some structures well developed. In the other we found some
differences in the eye, represented by the big volume of ocular glob and a large lens in horses. The
response of the HPA-axis to the used tests was negative. Cortisol levels at rest were elevated in horses and
they were the highest ones in cattle’s group who had a negative handling experiences."
