Perkinsus olseni in the short neck yellow clam, Paphia malabarica (Chemnitz, 1782) from the southwest coast of India

• Published in: Journal of invertebrate pathology Vol. 159; pp. 113 - 120
• Main Authors: Shamal, P., Zacharia, P.U., Binesh, C.P., Pranav, P., Suja, Gangadharan, Asokan, P.K., Pradeep, M.A., Rithesh, Ranjan, Vijayan, K.K., Sanil, N.K.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.11.2018
• Subjects: Histology; In-situ hybridization; Paphia malabarica; Perkinsus olseni; Phylogeny; Reservoir host; Sporulation; Paphia malabarica; Sporulation; Perkinsus olseni; Reservoir host; Histology; In-situ hybridization; Phylogeny
• ISSN: 0022-2011; 1096-0805
• DOI: 10.1016/j.jip.2018.10.001

[Display omitted] •Perkinsus olseni is reported from Paphia malabarica.•P. olseni isolates from various geographical locations reveal minimal genetic variation.•In spite of heavy infections, clams showed no observable symptoms.•The role of P. olseni in the decline/fluctuation of clam populations in the region remains a possibility. Parasites of the genus Perkinsus predominantly infect bivalves, and two species among them, P. olseni and P. marinus, are notifiable to OIE. P. olseni infections are known to cause extensive damage to wild as well as farmed bivalves globally with enormous implications to its fishery. Consequent to the initiation of a surveillance programme for aquatic animal diseases in India, Perkinsus infections were observed in many species of bivalves. The present paper describes P. olseni infections in the short neck yellow clam, Paphia malabarica from the southwest coast of India. Diagnosis of the parasite was carried out using Ray's Fluid Thioglycollate Medium culture, histology, in-situ hybridisation and molecular taxonomy. Pathology of infection and development of zoospores is also described. This forms the first report of a P. olseni infection in P. malabarica. High prevalence and intensity of infection of Perkinsus in clams raises concerns, as clam reserves in this geographical area sustain fisheries and the livelihoods of local fishing communities.