Description of Goussia kuehae n. sp. (Apicomplexa: Eimeriidae) infecting the Asian seabass, Lates calcarifer (Bloch) (Perciformes: Latidae), cultured in Malaysian fish farms

Abstract

Culturing fishes in marine cages is a rapidly developing area of marine aquaculture.The Asian seabass Lates calcarifer (Bloch) is a fast growing good quality fish that is readily cultured in intensive systems in the South Asian region and in Malaysia in particular. Although several papers have been published to date on viral, bacterial, parasitic and fungal organisms causing diseases in the Asian seabass, the occurrence of a coccidian infection in this species has only recently been recorded. We collected sporulated and unsporulated oöcysts of a new species of Goussia Labbé, 1986, from the mucus covering the epithelium of the intestine of L. calcarifer.This paper provides a description of Goussia kuehae n. sp. Sporulated oöcysts of this species are ellipsoidal, 3740 μm in length and 2830 μm in width. The ellipsoidal sporocysts are relatively small, 15.2-17 × 5.78 μm, and located loosely in the oöcyst. There are residual bodies both in the oöcysts and the sporocysts. Goussia kuehae n. sp. differs from all known species of Goussia in the large size of the oöcysts and in having two types of oöcyst residuum.

Infectious diseases reported in warm‐water marine fish cage culture in East and Southeast Asia—A systematic review

“…According to the single report of apicomplexan parasite from Malaysia, the infection was not associated with any serious clinical or pathological signs (Székely et al, 2013), which is consistent with observations from infected cage-reared European seabass in the Adriatic region (Gjurčević et al, 2017). However, in Spain, these parasites were observed to cause ascites, necrosis of the gastric epithelial cells and white faecal casts in European seabass and gilthead seabream (Alvarez-Pellitero & Sitjà-Bobadilla, 2002).…”

Intestinal coccidiosis of anadromous and landlocked alewives, Alosa pseudoharengus, caused by Goussia ameliae n. sp. and G. alosii n. sp. (Apicomplexa: Eimeriidae)

“…The oocyst wall was smooth compared to the irregular oocyst wall of G. ameliae and dimensions of oocysts in G. alosii were much larger than that reported for G. ameliae . In fact, the oocysts of G. alosii were larger than most other reports in Goussia species, with the exception of G. kuehae , which was reported to have very large oocysts measuring about 37.9 × 29.3 µm ( Szekely et al., 2013 ). The oocyst size of G. alosii was intermediate between that of G. ameliae and the large oocysts of G. kuehae .…”

“…Though little is known about the impacts of coccidiosis in fish hosts, it is often assumed that infections cause little disease under natural conditions, unless the host–parasite–environmental balance is disturbed ( Davies and Ball, 1993 ). There have been reports of suspected mortality caused by coccidians in cultured marine fish; Goussia kuehae was believed to cause mortality in Asian seabass, Lates calcarifer , due to low daily water exchange rates ( Gibson-Kueh et al, 2011 , Szekely et al, 2013 ). Additionally, coccidian infections have been suggested to reduce body condition of wild fish.…”

Seasonal intestinal coccidiosis in wild bluegill Lepomis macrochirus is associated with a spring bacterial epizootic

“…Notes: This species may be distinguished from other epicellular coccidia based on the larger size of the oocysts produced and host range. Oocysts are the largest described from epicellular coccidia except for G. kuehae (Székely, Borkhanuddin, Shaharom, Embong, & Molnár, ), which have oocysts that are even larger (37.9 by 29.3 µm). The environment and host differ significantly, with G. kuehae infecting Asian seabass from brackish waters of Malaysia and G. washuti n. sp.…”

“…Etymology: The species name is dedicated to Edmund Washuta, a fish health biologist who dedicated his career to understanding the health and characterizing parasites in fish populations in the state of New Jersey, USA.Notes: This species may be distinguished from other epicellular coccidia based on the larger size of the oocysts produced and host range. Oocysts are the largest described from epicellular coccidia except for G. kuehae(Székely, Borkhanuddin, Shaharom, Embong, & Molnár, 2013), which have oocysts that are even larger (37.9 by 29.3 µm). The environment and host differ significantly, with G. kuehae infecting Asian seabass from brackish waters of Malaysia and G.F I G U R E 7 Coelozoic myxozoan parasites detected in bluegills.…”