Microscopic study of development of renal nephrons in sturgeon larvae and fingerlings

In order to study development of nephrons in larval and fingerling stages of sturgeon (Acipenser persicus), a total number of 60 samples of larvae and Fingerlings were randomly collected and immediately were fixed in Buin’s fluid. After routine histological procedures and sectioning at 5-6 micrometers, they were stained with hematoxylin and eosin and studiedunder light microscope. The results showed that in one day after hatching, the abdomen was filled with yolk sac which was disappeared in the next days and the growth of organs was developed. Renal corpuscles were observed during the first week. Renal corpuscles and urinary tubules were obvious after fourth day of hatching. During the next days, the kidneys progressed gradually to the caudal parts and also the tubules and renal corpuscles increased in number. Also in days twenty to twenty five, beside the growth and increasing of renal corpuscles, complete differentiation of urinary tubules occured. In days thirty five to forty complete growths of tubules and renal corpuscles were observed, moreover each tubule showed its own cytoplasm staining, and the presence of hematopoietic tissues and lymphatic tissues were completely obvious.