Infection and Propagation of Cryptocaryon irritans on Golden Pompano (Trachinotus spp.) in Vietnam

Date Received: Jul 18, 2025

Date Accepted: Oct 01, 2025

Date Published: Dec 31, 2025

DOI: https://doi.org/10.31817/vjas.2025.8.4.04

Views

46

Download

19

Issue: Vol. 8 No. 4 (2025): Vietnam Journal of Agricultural Sciences

Section:

ANIMAL SCIENCE – VETERINARY MEDICINE – AQUACULTURE

How to Cite:

Anh, K., Manh, V., Thiet, N., Nguyen, N., Quan, D., Hung, N. M., … Van, K. V. (2025). Infection and Propagation of Cryptocaryon irritans on Golden Pompano (Trachinotus spp.) in Vietnam. Vietnam Journal of Agricultural Sciences, 8(4). https://doi.org/10.31817/vjas.2025.8.4.04

Infection and Propagation of Cryptocaryon irritans on Golden Pompano (Trachinotus spp.) in Vietnam

Kim Kim Minh Anh 1 , Vu Duc Manh 1 , Nguyen Cong Thiet 1 , Nguyen Phuc Bao Nguyen 1 , Do Ngoc Anh Quan 2 , Nguyen Manh Hung 2 , Truong Dinh Hoai 1   , Kim Van Van (*) 1

  • Corresponding author: [email protected]
  • 1 Faculty of Fisheries, Vietnam National University of Agriculture, Hanoi 12400, Vietnam
  • 2 Institute of Biology, Vietnam Academy of Science and Technology, Hanoi 11355, Vietnam

    • Keywords

    Cryptocaryon irritans, mariculture system, parasite infection, Trachinotus spp

    Abstract


    Cryptocaryon irritans is an ectoparasitic protozoan responsible for white spot disease, posing a significant threat to mariculture systems in Vietnam. This study aimed to isolate and propagate C. irritans, and to establish an experimental infection model in Trachinotus spp. (5-7cm in length) under laboratory conditions. Between February and June 2025, a total of 106 fish samples were sourced from aquaculture operations in Quang Ninh and Khanh Hoa, revealing an average C. irritans infection rate of 59.43%, with the highest prevalence observed during March and April. Infected fish exhibited clinical signs including skin darkening, mucus loss, white spots on the skin and gills, fin erosion, ulcerations, and tissue damage. The parasite was successfully cultured at the trophont stage and was propagated to the tomont and theront stages at 28-30°C, achieving a conversion efficiency of 61.7% after 48 hours and yielding an average of 150-300 theronts per tomont. These theronts were introduced to Trachinotus spp. at a density of 5,000 theronts per 250L tank (50 fish) at a temperature of 28°C. The infection progressed rapidly, with trophonts observed within 2-3 days and cumulative mortality reaching 100% by day seven. The established infection model offers a robust platform for further research in epidemiology, immunology, and therapeutic interventions against C. irritans.

    References

    Colorni A. (1985). Aspects of the biology of Cryptocaryon irritans, and hyposalinity as gilt-head sea bream Sparus aurata. Diseases of Aquatic Organisms. 1: 19-22.

    Colorni A. & Burgess P. (1997). Cryptocaryon irritans Brown 1951, the cause of ‘white spot disease’in marine fish: an update. Aquarium Sciences and Conservation. 1: 217-238.

    Dan X., Li A., Lin X., Teng N. & Zhu X. (2006). A standardized method to propagate Cryptocaryon irritans on a susceptible host pompano Trachinotus ovatus. Aquaculture. 258(1-4): 127-133.

    Diggles B. & Lester R. (1996). Infections of Cryptocaryon irritans on wild fish from southeast Queensland, Australia. Diseases of aquatic organisms. 25(3): 159-167.

    Gibson-Kueh S. (2012). Diseases of Asian Sea Bass (or Barramundi), Lates calcarifer Bloch, Murdoch University, 22 pages.

    Hanh T. T. M., Yen P. T., Thanh P. T., Nguyen N. T., Truong D. X. & Van P. T. (2018). Status of parasitic infection on Pompano (Trachinotus spp.) cage culture in Hai Phong. Vietnam Journal of Science, Technology and Engineering. 60(9).

    Li Y., Jiang B., Mo Z., Li A. & Dan X. (2022). Cryptocaryon irritans (Brown, 1951) is a serious threat to aquaculture of marine fish. Reviews in Aquaculture. 14(1): 218-236.

    Pattipeiluhu S. M., Rijoly S. M., Sahetapy J. M., Pattinasarany M. M., Palinussa E. M., Pattipeilohy C. E. & Pelu M. A. (2024). Parasites Infestation on Cultured Barramundi (Lates calcarifer) and the Impact of Fish Health. IOP Conference Series: Earth and Environmental Science. IOP Publishing. 012010.

    Sun J. L., Jiang T., Gu Y., Song F. B., Wen X. & Luo J. (2022). Differential immune and metabolic responses underlie differences in the resistance of Siganus oramin and Trachinotus blochii to Cryptocaryon irritans infection. Fish & Shellfish Immunology. 120: 166-179.

    Van K. V. (2018). Study on white spot disease in marine ornamental fish. Journal of Veterinary Sciences and Technology. 25: 76-84.

    Van K. V. & Nhinh D. T. (2018). The prevalence of Cryptocaryon irritans in wild marine ornamental fish from Vietnam. IOP Conference Series: Earth and Environmental Science. IOP Publishing. 012094.

    Watanabe Y., How K. H., Zenke K., Itoh N. & Yoshinaga T. (2018). Dormancy induced by a hypoxic environment in tomonts of Cryptocaryon irritans, a parasitic ciliate of marine teleosts. Aquaculture. 485: 131-139.

    Watanabe Y., How K. H., Zenke K., Itoh N. & Yoshinaga T. (2020). Stable and quantitative small-scale laboratory propagation of Cryptocaryon irritans. MethodsX. 7: 101000.

    Yambot A. V. & Song Y.-L. (2004). Short term in vitro culture of Cryptocaryon irritans, a protozoan parasite of marine fishes. Fish Pathology. 39(4): 175-181.

    Yin F., Bao P., Liu X., Yu Y., Wang L. & Wang L. (2019). Antiparasitic effect of copper alloy surface on Cryptocaryon irritans in aquaculture of Larimichthys crocea. Applied and environmental microbiology. 85(3): e01982-18.

    Yin F., Gong Q., Li Y., Dan X., Sun P., Gao Q., Shi Z., Peng S. & Li A. (2014). Effects of Cryptocaryon irritans infection on the survival, feeding, respiratory rate and ionic regulation of the marbled rockfish Sebastiscus marmoratus. Parasitology. 141(2): 279-286.

    Zeng S., Duan Y., Li X., Hu Y., Mo Z., Dan X. & Li Y. (2023). Effects of Cryptocaryon irritans infection on the histopathology, oxidative stress, immune response, and intestinal microbiota in the orange-spotted grouper Epinephelus coioides. Fish and Shellfish Immunology. 133: 108562.

    Zheng L., Qiu J., Chen J., Zheng W.-q. & Pan Y. (2020). Histopathological changes and piscidin 5-like location in infected Larimichthys crocea with parasite Cryptocaryon irritans. Fish & Shellfish Immunology. 99: 52-58.

    Zhong Z., Wu X., Bai M., Huang X., Zheng Q. & Ai C. (2023). Treatments of orange‐spotted grouper (Epinephelus coioides) against Cryptocaryon irritans with• OH, ClO2 or HCHO: Survival, physiological and histological response. Journal of Fish Diseases. 46(3): 215-227.

    Zhou L., Wu J., Kang T., Wang L., Yuan Y., Jiang L., Yu Y., Xie X. & Yin F. (2023). Sustainable development of factory aquaculture through automation of ultraviolet parasiticide for the prevention and control of cryptocaryoniasis. Pest Management Science. 79(4): 1372-1380.

    Zhou L., Zhou R., Xie X. & Yin F. (2024). Characteristics and risk assessment of cryptocaryoniasis in large yellow croaker (Larimichthys crocea) at different densities in industrialized aquaculture. Aquaculture. 582: 740501.