Polydora index and histopathological lesions in the mangrove oyster Crassostrea gasar from the Aby and Ebrié lagoon systems
Paper Details
Polydora index and histopathological lesions in the mangrove oyster Crassostrea gasar from the Aby and Ebrié lagoon systems
Abstract
The mangrove oyster Crassostrea gasar plays a vital ecological and socio-economic role in the Ébrié and Aby lagoons of Côte d’Ivoire. However, it is threatened by infestations of boring worms from the Polydora genus, which cause shell damage that can reduce both its commercial value and physiological health. This study aims to quantify the Polydora Index (PI) and the prevalence of tissue lesions in C. gasar at three sites, Azito and Grand-Bassam on Ébrié Lagoon and Assinie on Aby Lagoon, based on a sample of 1,080 oysters. Infestation levels were classified into five severity classes and histopathological lesions were assessed in the mantle, gills, and gonads. Results show that Assinie had the lowest PI (0.16) and only exhibited gill necrosis (21.1%). Grand-Bassam and Azito had higher PI (0.24 and 0.33, respectively) and a greater prevalence of lesions: necrosis (32.5% to 51.4%), abscesses (12.2% to 41.9%), and neoplasia (14.2% to 28.6%). A clear correlation was observed between shell infestation levels and lesion prevalence, especially in Azito, where up to 85% of infested oysters showed necrosis. The study highlights the need to monitor such infestations as indicators of environmental stress and potential threats to oyster farming.
Catherine M, Blateau D, Mazurie J, Le Bec C. 1990. Anomalies des coquilles d’huîtres creuses Crassostrea gigas observées sur le littoral français en mai-juin 1989 dues au ver Polydora et aux peintures antisalissures. Rapports IFREMER, 109p. https://archimer.ifremer.fr/doc/00104/21491/
Catherine M, Dumont F, Ménanteau C, Pézeron A. 1996. Abnormalities of the Crassostrea gigas oyster shells due to Polydora sp., observed in Pen-Bé and Mesquer harvesting areas (Loire-Atlantique) from 1988 to 1989. Rapport IFREMER, 42p.
Chambon C, Legeay A, Durrieu G, Gonzalez P, Ciret P, Massabuau J-C. 2007. Influence of the parasite worm Polydora sp. on the behaviour of the oyster Crassostrea gigas: A study of the respiratory impact and associated oxidative stress. Marine Biology 152(2), 329‑338. https://doi.org/10.1007/s00227-007-0693-1
Cole SM, Dorgan KM, Walton W, Dzwonkowski B, Coogan J. 2020. Seasonal and spatial patterns of mudblister worm Polydora websteri infestation of farmed oysters in the northern Gulf of Mexico Aquaculture Environment Interactions 12, 297‑314. https://doi.org/10.3354/aei00365
Costa LC, De O, Carvalho A, Holanda M, Santos J, Borges L, Guterres B, Nam Junior J, Fonseca V, Muller L, Romano L, Botelho S, Pias M, Ventura J, Poersch LH. 2023. Biological Responses of Oyster Crassostrea gasar Exposed to Different Concentrations of Biofloc. Fishes 8(12), 586. https://doi.org/10.3390/fishes8120586
Da Silva PM, Scardua MP, Vianna RT, Mendonça RC, Vieira CB, Dungan CF, Scott GP, Reece KS. 2014. Two Perkinsus spp. Infect Crassostrea gasar oysters from cultured and wild populations of the Rio São Francisco estuary, Sergipe, northeastern Brazil. Journal of Invertebrate Pathology 119, 62‑71. https://doi.org/10.1016/j.jip.2014.04.005
Fleury PG, Goyard E, Mazurié J, Claude S, Bouget JF, Langlade A, Le Coguic Y. 2001. The assessing of Pacific oyster (Crassostrea gigas) rearing performances by the IFREMER/REMORA network : Method and first results (1993–98) in Brittany (France). Hydrobiologia 465(1‑3), 195‑208. https://doi.org/10.1023/A:1014531128458
Haberkorn H, Lambert C, Le Goïc N, Guéguen M, Moal J, Palacios E, Lassus P. Soudant P. 2010. Effects of Alexandrium minutum exposure upon physiological and hematological variables of diploid and triploid oysters, Crassostrea gigas. Aquatic Toxicology 97(2), 96‑108. https://doi.org/10.1016/j.aquatox.2009.12.006
Hégaret H, Da Silva PM, Wikfors GH, Haberkorn H, Shumway SE, Soudant P. 2011. In vitro interactions between several species of harmful algae and haemocytes of bivalve molluscs. Cell Biology and Toxicology 27(4), 249‑266. https://doi.org/10.1007/s10565-011-9186-6
Hégaret H, da Silva PM, Wikfors GH, Lambert C, De Bettignies T, Shumway SE, Soudant P. 2007. Hemocyte responses of Manila clams, Ruditapes philippinarum, with varying parasite, Perkinsus olseni, severity to toxic-algal exposures. Aquatic Toxicology 84(4), 469‑479. https://doi.org/10.1016/j.aquatox.2007.07.007
Hégaret H, Wikfors GH. 2005. Effects of natural and field-simulated blooms of the dinoflagellate Prorocentrum minimum upon hemocytes of eastern oysters, Crassostrea virginica, from two different populations. Harmful Algae 4(2), 201‑209. https://doi.org/10.1016/j.hal.2003.12.005
Joshy A, Sharma SRK, Mini KG, Gangadharan S, Pranav P. 2022. Histopathological evaluation of bivalves from the southwest coast of India as an indicator of environmental quality. Aquatic Toxicology 243, 106076. https://doi.org/10.1016/j.aquatox.2022.106076
Martoja R, Martoja-Pierson M. 1967. Initiation aux techniques de l’histologie animale. https://www.sidalc.net/search/Record/oai:fvet.uba.ar:biblioteca:1082/Description
Queiroga FR, Marques-Santos LF, Hégaret H, Soudant P, Farias ND, Schlindwein AD, Mirella da Silva P. 2013. Immunological responses of the mangrove oysters Crassostrea gasar naturally infected by Perkinsus sp. In the Mamanguape Estuary, Paraíba state (Northeastern, Brazil). Fish and Shellfish Immunology 35(2), 319‑327. https://doi.org/10.1016/j.fsi.2013.04.034
Queiroga FR, Vianna RT, Vieira CB, Farias ND, Silva PMD. 2015. Parasites infecting the cultured oyster Crassostrea gasar (Adanson, 1757) in Northeast Brazil. Parasitology 142(6), 756‑766. https://doi.org/10.1017/S0031182014001863
Sato-Okoshi W, Okoshi K, Abe H, Dauvin J-C. 2023. Polydorid species (Annelida: Spionidae) associated with commercially important oyster shells and their shell infestation along the coast of Normandy, in the English Channel, France. Aquaculture International 31(1), 195‑230. https://doi.org/10.1007/s10499-022-00971-y
Yapi JN, Blé MC, Etchian AO, Kadjo V, Soro D, Yao K. 2016. Actors and effort of the artisanal harvesting of mangrove oyster Crassostrea gasar along the littoral lagoons Ebrié and Aby (Côte d’Ivoire). International Journal of Biosciences (IJB) 9(6), 45‑54. http://dx.doi.org/10.12692/ijb/9.6.45-54
Yapi JN, Ble MC, Etchian AO, Yao K. 2017. Population Dynamics of Mangrove Oyster, Crassostrea gasar of the Lagoons Ebrié and Aby (Côte d’Ivoire). International Journal of Sciences: Basic and Applied Research (IJSBAR) 36(8), 122-137.
Zhang W, Mao J, Yuan, C, Yang J, Han B, Wang X, Ding J, Chang Y. 2020. Histological Changes in the Mantle Tissue of the Yesso Scallop Patinopecten yessoensis Shell Infested by Polydora. The Journal of Shellfish Research 39(1), 87‑97. https://doi.org/10.2983/035.039.0109
Jean Noel Yapi, Wadje Jerome N’glouan, Vincent Kadjo, Assoi Olivier Etchian, Melecony Celestin Ble, Ibrahim Imorou Toko, Sylvanus Koui, Kouakou Yao, 2025. Polydora index and histopathological lesions in the mangrove oyster Crassostrea gasar from the Aby and Ebrié lagoon systems. Int. J. Biosci., 27(3), 169-176.
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