Seasonal and Water Quality Significance of Gregarine Protozoan Parasites Occurrence in Wild Bivalve, Anadara cornea (Reeve, 1844) from Terengganu, Malaysia.
Mohd Ihwan Zakariah* (a,b), Hassan Mohd Daud (b), Mhd Ikhwanuddin (a,c), Nor Asma Husna Yusoff (a), Farizan Abdullah (a), Wahidah Wahab (a), Ahmad Shuhaimi Draman (a), Ahmad Najmi Ishak (a) and Marina Hassan (a,c)

(a) Higher Institution Centre of Excellence (HICoE), Institute of Tropical Aquaculture and Fisheries (AKUATROP), Universiti Malaysia Terengganu, 21300 Kuala Nerus, Terengganu, Malaysia.

(b) Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Darul Ehsan, Malaysia.

(c) STU-UMT Joint Shellfish Research Laboratory, Shantou University, Shantou 515063, China

*ihwanz[at]umt.edu.my, ikhwanuddin[at]umt.edu.my, marina[at]umt.edu.my.

Abstract

Malaysia is known as a country that experience two main seasonal patterns i.e., monsoon and non-monsoon season. Three different categories of seasons based on the quantity of rainfall were divided by previous studies started from January to December 2018 which are dry season, moderate season and rainy season. Wild bivalve, Anadara cornea populations at Setiu Lagoon in Terengganu, Malaysia was examined for gregarine parasites for a year. The objective of this study was to associate the incidence of gregarine in common wild bivalves, A. cornea (Reeve, 1844) concerning seasons and water quality parameters. From the study, the total number of phagocytes found was n = 33,239 with a total of 480 host samples. The total prevalence of the parasites was 97.5% with a 95% confidence interval value which was CI=96.1% to 98.9%. The prevalence of the parasites was significantly high during the rainy season as compared to another season (dry and moderate). The findings also proved that the intensity of the parasites decreased at every transition of season. In-depth, correlation between the prevalence of the parasites vice versa season and water quality might be contributed to the intensity of the parasite infestation needs to be clarified.

Keywords: protozoan parasites, gregarine, seasonal, water quality, Anadara cornea

Topic: Aquatic Biodiversity (International)