Gonapodasmius epinepheli observed in cage cultured orange spotted grouper (Epinephelus coioides) in Southern Thailand: geographical distribution of parasite and host response

Abstract

Gonapodasmius epinepheli Abdul-Salam, Sreelatha & Farah, 1990, a didymozoid trematode, was found in orange spotted grouper (Epinephelus coioides, Hamilton, 1822) cultured in cages in Southern Thailand, both on the east coast (Gulf of Thailand) and the west coast (Indian Ocean). The parasite encysted on the primary lamellae of the gills. Histological sections revealed that larvae were primarily embedded underneath the gill epithelium and eggs of the parasite were distributed in some organs such as gill epithelium, heart and macrophage centers in the head kidney. Pathological changes and host response were shown mainly on gill lamellae, e.g. reduction and destruction of secondary lamellae. Prevalence of parasite and its life cycle are discussed in this report.

Keywords

• <em>Gonapodasmius epinepheli</em>
• digenetic trematode
• grouper
• <em>Epinephelus coioides</em>