Morphology of cattle's mesonephros at the germinal period of embriogenesis

The mesonephros of 12 cattle’s embryos of 30-34 days age was investigated by histological, morphometrical and histochemical methods. After fixation in 4 % neutral formaldehyde solution, embryos were embedded in paraffin. The sections obtained on rotary microtome were stained with hematoxylin and eosin, chrome hematoxylin and eosin, Mallory’s method. Protein and acide phosphatase activity in structures of mesonephros were detected by histochemical methods. The results of measurement were processed statistically. The work was performed in the morphological laboratory of Institute of Veterinary Medicine and Biotechnology of Omsk State Agrarian University. It was found that mesonephros of 30 days age cattle’s embryos have a form typical for mammalian embryos. The most of mesonephrons of cranial and middle parts of organ have a features of intensive functional activity. The formation of new mesonephrons occurred in the caudal part of mesonephros. The dimensions and structure of mesonephric corpuscules, glomerules and tubules changes in cranio-caudal vector. This fenomen reflects phylohistogenesis of mesonephros. Numerous epiteliocytes of mesonephric tubules have a signes of apocrine secretion, that illustrate active participation in excretory function of mesonephros by secretion of mineral substances. The functional activity of mesonephros at germinal period grows with morphofunctional differentiation of mesonephrons, but involutive processes in it were not pronounced.