The embryonic development of the pig excretory system.

Porcine Research

Karalova E.¹ 

关键词: embryogenesis;    urinary system;    pronephros;    mesonephros;    metanephros;    kidney;   

DOI  :  

学科分类：生物科学（综合）

来源: Bioflux SRL

【 摘 要 】

It was shown, that on the 15th days after the conception (impregnation) in the pig embryosthe prenephros have been revealed, consisted of several channel-like structures. They existed till the 3-rd week of embryogenesis, and then reduced, and by the 25th day of the pig embryonic developmentthe primary kidneys came apparent, getting the maximal growth in the 25-35-days pig embryos. On the45-th days of embryogenesis a big amount of the highly convoluted urinary tubules and also multipleMalpighean bodies have been revealed in them. Then mesonephros underwent involution, and on the65-days embryos’ slides the Malpighean glomeruli of the primary kidney are seen at the phases ofdegeneration and atrophy. Consequently, mesonephros functions during the first half of the pigintrauterine development, and then is followed by transformation into metanephros, which thereaftermaintains as the final mature kidney. In the 75-days pig fetus the renal capsule is already seen, andunderneath of which the cortical and medullar layers are clearly distinguished. The latter is formed bythe collecting tubules, whereas the cortical layer is represented by the Malpighean bodies and theconvoluted tubules. In mean, the Malpighean bodies’ amount makes up 6-7/mm2 of the section squarearea. Their structure is very similar to the structure of the Malpighean bodies of adult animal. The timedynamics of interchanges of prоnephros, the primary and final kidneys and their relative sizes have beendetected. It was revealed, that the maximal relative square area was for the final kidney in the 45-65-days embryos. Then, because of the pig fetus accelerated growth, forestalling the kidney growth, therelative square areas of kidneys becomes decreased. In result of the kidneys’ weightings during the fetalperiod of development a significant absolute increase of the kidneys weight was revealed, although therelative weight and the growth intensity decrease during the fetal period of development, what probably,is conditioned by the kidneys earlier intensive growth as long ago as in the embryonic period ofdevelopment.

【 授权许可】

CC BY