Gregarines are protozoa that occur within the digestive tract and tissues of various invertebrate animals such as shrimp.
In this survey 15 marine broodstocks of Penaeus indicus from Jask area and 119 cultured shrimps from cultured farms were supplied and carried to laboratory.
According to life cycle of gregarine, (Johnson, 1989) it is assumed that presence of protozoan gregarine among broodstock shrimps can be due to consumption of natural food and existance of intermediate hosts and as a result to be completion of life cycle of these protozoan in natural conditions. On the other hand absence of these parasites among cultured shrimp can be due to consumption of prepared (inert) food and lack of completion of alternate hosts and intermediate hosts and consequently lack of completion of life cycle of these parasites in the cultured condition.