Introduction: Meat, fish and other livestock to various reasons that are consumed orally
is preferred. Given the importance of the health of fish to be used in human society
seems essential. Gill necrosis syndrome is one of the most important diseases in the
aquaculture industry. The purpose of this study was to investigate the prevalence of
histopathological gill necrosis in carp carrot opioid Lake is distracted. Methods: In this
study, 100 pieces of carp (carrots) Kazeroon distracted Lake fishing and ice
compartments Rubber powder was sent to the lab. Fish Pathology Laboratory, Faculty
of Veterinary Medicine, the measure biometric characteristics such as weight, length
and ... And clinical studies , necropsy was attempted and the observations recorded , the
fish gills were isolated and transferred to 10% formalin solution. The gill tissue sections
were stained with hematoxylin and eosin, they were studied. Results: In 31 % of cases,
one or microscopic signs were observed in 69 % of cases, no symptoms were reported
pathology. The most important microscopic signs, including the collapse of the
cytoplasm membrane 28, 23 hypertonic cytoplasm, nucleus Hypertrophy 25, 17 pick
nose, 11 is replaced by connective tissue.
