en Genetics Genetics پژوهشي Orginal research papers <p>Certain parasites can cause severe diseases in shrimp. Among these, protozoa are very important. The objective of our study was to describe the signs, prevalence, and intensity of hemocytosis, a new disease in shrimp, Fenneropenaeus indicus. The experimental design included three groups, one treatment as infected shrimp or group B and 2 controls with non-infected but exposure to White Spot Syndrom Virus (WSSV) shrimp as group A and non-infected non- exposure to WSSV shrimp as group C in triplicate. The results revealed that Hemocytosis associated with a decrease in hyalinocytes and large-granulocytes (less than 8%) and a considerable increase in semi-granulocytes in group A and B in contrast to group C that Hyalinocyte increased. This infection made the shrimp susceptible to WSSV disease. It is believed that Hemocytosis causes a condition which can result in a rapid mortality among susceptible species, P. indicus when exposure to WSSV is occurred.</p> Shrimp, penaeus indicus, Hemocytosis, Intrahemocyte, Mortality 605 619 http://jifro.ir/browse.php?a_code=A-10-4-3&slc_lang=en&sid=1 S. Kakoolaki bsh443@gmail.com 100319475328460037412 100319475328460037412 Yes I. Sharifpour 100319475328460037413 100319475328460037413 No M. Sharifrohani 100319475328460037414 100319475328460037414 No H. A. Ebrahimzadeh Mousavi 100319475328460037415 100319475328460037415 No M. Afsharnasab 100319475328460037416 100319475328460037416 No N. Dashtiannasab 100319475328460037417 100319475328460037417 No A. Nezamabadi 100319475328460037418 100319475328460037418 No H. 100319475328460037419 100319475328460037419 No