Today the fish specially types of protein such as salmon specify an important share of
economic and animal protein sources in lots of countries. Rainbow salmon is rapidly
developing all over Iran too. The reviews stated that mineral deposits commonly within the
tubules, ducts and ureters urinary excretion of the month, both in farmed and wild fish
happen and they call this nephrocalcinosis (calcium deposits in the kidneys). According to the
economic importance of such fish the investigation on outbreak of nephrocalcinosis among
rainbow salmons is the most major subject of present study. Study was designed to
investigate on outbreak of nephrocalcinosis among rainbow salmons in Qadir field of
Noorabad Mamasani of Fars Province on 2010 samples were taken from the field and 75samples were chosen randomly. After spinal cord injury, biometry and then necropsy was
performed to obtain a sample of kidney tissue. All samples preserved in 4% formalin and
then transferred to the pathology laboratory of Veterinary Medicine and acting opioid
preparation of pathology slides and staining Hematocalcilin - eosin. The sections were
examined pathologically. Among the samples, there were no nephrocalcinosis symptoms but
a degree of complicated pathology of renal tubular dilation and hyaline casts, acute tubular
necrosis and renal pathology was observed to increase melanin in some sections. According
to this fact that amount of deaths were low, regarding transition coefficient of nutrition in
fishes' food had depletion, the corps of fish were of low quality. Therefore further research is
recommended
