Electronic Journal of Polish Agricultural Universities is the very first Polish scientific journal published exclusively on the Internet, founded on January 1, 1998 by the following agricultural universities and higher schools of agriculture: University of Technology and Agriculture of Bydgoszcz, Agricultural University of Cracow, Agricultural University of Lublin, Agricultural University of Poznan, Higher School of Agriculture and Teacher Training Siedlce, Agricultural University of Szczecin, and Agricultural University of Wroclaw. ELECTRONIC JOURNAL OF POLISH AGRICULTURAL UNIVERSITIES 2003 Volume 6 Issue 2 Series VETERINARY MEDICINE Copyright © Wydawnictwo Akademii Rolniczej we Wroclawiu, ISSN 1505-0297 POSPIESZNY N., KLEĆKOWSKA J., JANECZEK M. 2003. MORPHOLOGY AND DEVELOPMENT OF DEPRESSIVE NERVE (nervus depressor) OF PIG AT PRENATAL STAGE Electronic Journal of Polish Agricultural Universities, Veterinary Medicine, Volume 6, Issue 2. Available Online http://www.ejpau.media.pl MORPHOLOGY AND DEVELOPMENT OF DEPRESSIVE NERVE (nervus depressor) OF PIG AT PRENATAL STAGE Norbert Pospieszny, Joanna Klećkowska, Maciej Janeczek Department of Veterinary Anatomy and Histology, Agricultural University of Wroclaw, Poland ABSTRACT INTRODUCTION MATERIAL AND METHODS RESULTS DISCUSSION CONCLUSIONS REFERENCES ABSTRACT The research was conducted on 117 pig fetuses from 12 uteri. The pigs came from 5-7th, 10-11th and 12-13th week of pregnancy. Morphological analysis of the depressive nerve and biomechanics of the nerve were described. The initial form of depressive nerve, characteristic for the first weeks of prenatal stage is usually a built from single elements. The origin of fetus from the same horns of uteri and their sex have no important influence on the morphology and the development of the nerve in their prenatal stage. Key words: pig, prenatal period, depressive nerve INTRODUCTION The research on the development of autonomous nervous system has an important, cognitive value for morphology, physiology, pathology and clinical research. It results both, from the role the autonomic nervous system plays in the maintenance of the correct function of all system organs and in pathogenesis of separate disease entity. Its importance is also connected with the morphological complex structure of the system, including the vagus nerve.