Liji Xie, Zhixun Xie

Abstract  Marteilia spp. is listed as a notifiable parasite by the Office International des Epizooties (OIE), and cause physiological disorders and eventually death of the shellfish. Little is known about the prevalence of Marteilia spp. in shellfish of China. Therefore we investigated the prevalence of Marteilia spp. in 13 species of shellfish collected in the coastal areas of China between 2006 to 2012. A total of 11,581 individual shellfish comprising 13 different species was collected from seven bay areas in China. The shellfish was tested for the prevalence of Marteilia spp. following a PCR protocol recommended by OIE. Marteilia spp. was found in the shellfish samples (Crassostrea rivularis, Crassostrea gigas and Crassostrea angulate), Meretrix meretrix, Chlamys nobilis, Ruditapes philippinarum, Perna viridis, Tegillarca granosa, and Sinonovacula constricta. The detection rates of Marteilia spp. by PCR method ranged from 0% to 6.67%, with R. philippinarum (6.67%) showing the highest detection rate. Marteilia spp. sequence of the individual positive shellfish had a high sequence homology (97.4% to 99.6%) with the sequences of other Marteilia typ e “M”. Mixed positive of Marteilia spp. with other protozoan species (Haplosporidium nelsoni and Perkinsus spp.) was a common phenomenon (26.28%).
Keywords: Shellfish, Marteilia spp., PCR detection, Chinese coast.