First report of Perkinsus beihaiensis in Crassostrea madrasensis from the Indian subcontinent

Sanil, N K and Suja, G and Lijo, J and Vijayan, K K (2012) First report of Perkinsus beihaiensis in Crassostrea madrasensis from the Indian subcontinent. Diseases of Aquatic Organisms (DAO), 98 . pp. 209-220.

[img]
Preview
PDF
1527Kb

Abstract

Protozoan parasites of the genus Perkinsusare considered important pathogensresponsible for mass mortalities in many wild and farmed bivalve populations. The present studywas initiated to screen populations of the Indian edible oyster Crassostrea madrasensis, a promis-ing candidate for aquaculture along the Indian coasts, for the presence of Perkinsusspp. Thestudy reports the presence of P. beihaiensisfor the first time in C. madrasensispopulations fromthe Indian subcontinent and south Asia. Samples collected from the east and west coasts of Indiawere subjected to Ray’s fluid thioglycollate medium (RFTM) culture and histology which indicatedthe presence of Perkinsusspp. PCR screening of the tissues using specific primers amplified theproduct specific to the genus Perkinsus. The taxonomic affinities of the parasites were determinedby sequencing both internal transcribed spacer (ITS) and actin genes followed by basic localalignment search tool (BLAST) analysis. Analysis based on the ITS sequences showed 98 to 100%identity to Perkinsusspp. (P. beihaiensisand Brazilian Perkinsussp.). The pairwise genetic dis-tance values and phylogenetic analysis confirmed that 2 of the present samples belonged to the P.beihaiensisclade while the other 4 showed close affinities with the Brazilian Perkinsussp. clade.The genetic divergence data, close affinity with the Brazilian Perkinsussp., and co-existence withP. beihaiensisin the same host species in the same habitat show that the remaining 4 samplesexhibit some degree of variation from P. beihaiensis.As expected, the sequencing of actin genesdid not show any divergence among the samples studied. They probably could be intraspecificvariants of P. beihaiensishaving a separate lineage in the process of evolution.

Item Type:Article
Uncontrolled Keywords:Edible oyster; Crassostrea madrasensis; Protozoan parasite; Perkinsus beihaiensis; Brazilian Perkinsus sp.; Indian subcontinent
Subjects:Molluscan Fisheries > Edible oyster
Fish Biotechnology
Divisions:CMFRI-Cochin > Marine Biotechnology
ID Code:9043
Deposited By:Arun Surendran
Deposited On:25 Sep 2012 13:33
Last Modified:18 Jul 2013 09:24

Repository Staff Only: item control page