Các nghiên cứu trước đây cho thấy ozon nanobubble và oxy nanobubble có khả năng nâng cao hiệu quả ấp trứng cá chép (Cyprinus carpio) trong điều kiện phòng thí nghiệm, đồng thời mở ra tiềm năng ứng dụng ở quy mô sản xuất. Trong nghiên cứu này, trứng cá chép được ấp với mật độ 40.000 trứng/L trong bể 100 lít. Hai nghiệm thức được thực hiện. Ở nghiệm thức nanobubble, trứng cá 24 giờ sau thụ tinh được tiếp xúc với nước chứa ozon nanobubble nồng độ 0,51 ± 0,03 mg/L trong 2 giờ, sau đó bổ sung oxy nanobubble để duy trì hàm lượng oxy hòa tan từ 9–10 mg/L. Nhóm đối chứng không được xử lý bằng ozon nanobubble hoặc oxy nanobubble. Chất lượng nước và tỷ lệ nhiễm nấm trên trứng được theo dõi đến 72 giờ sau thụ tinh. Kết quả cho thấy ở nghiệm thức nanobubble, chất lượng nước được cải thiện (COD, NO₂⁻ thấp hơn) và giảm tỷ lệ trứng bị nhiễm nấm. Tỷ lệ nở ở nhóm xử lý nanobubble đạt 91,41 ± 0,62%, cao hơn đáng kể so với 76,47 ± 1,46% ở nhóm đối chứng. Kết quả nghiên cứu cho thấy công nghệ ozon nanobubble và oxy nanobubble có tiềm năng ứng dụng rộng rãi trong ương ấp trứng của các loài cá khác.

Lactococcus garvieae is an emerging pathogen in aquaculture, with increasing reports of outbreaks in tilapia farming across Asia. In this study, we investigated two disease outbreaks in tilapia (Oreochromis spp.) cage farms in Northern Vietnam in 2024. Affected fish exhibited clinical signs including exophthalmia, scale hemorrhages, and internal lesions such as hepatobiliary swelling and ascites, empty gut and intestinal hemorrhage. Bacterial isolates obtained from diseased fish were initially misidentified as Streptococcus agalactiae based on biochemical profiling, but were subsequently confirmed as L. garvieae using MALDI-TOF Mass Spectrometry and 16S rRNA sequencing. Whole-genome sequencing of eight isolates revealed remarkable genomic homogeneity, with all strains assigned to multilocus sequence type ST95 and showing <= 9 SNPs across the core genome. Comparative phylogenomic analysis placed the Vietnamese isolates within a clonal subclade together with ST95 genomes from fish and human sources in East Asia, indicating recent expansion and possible regional transmission. Antimicrobial resistance gene screening detected only the mdt(A) and lsaD, consistent with high resistance to erythromycin, tetracycline, and doxycycline observed phenotypically. No plasmid-associated resistance genes were identified. Our findings highlight the emergence of a clonal L. garvieae ST95 lineage in Vietnamese aquaculture, characterized by high phenotypic antimicrobial resistance, and high genomic clonality. All L. garvieae strains from tilapia carried the full complement of 53 known virulence genes, including capsule biosynthesis genes, hemolysins (hly1-3), and LPxTG-anchored adhesins, underscoring their high pathogenic potential and explaining the severity of the clinical manifestations. These results underscore the importance of routine genomic surveillance, and strengthened biosecurity to mitigate the risk of further spread of L. garvieae in farmed fish populations. Although L. garviae is susceptible to only some antimicrobials traditionally used in aquaculture, the development of vaccines is needed.

Nanobubble technology has recently been applied in various aquaculture systems. However, its application in seed production remains understudied. This study evaluates the effects of ozone nanobubbles (O3NB) during the embryonic stage and oxygen nanobubbles (O2NB) during the fry stage in rainbow trout (Oncorhynchus mykiss). Fertilized eggs at stage pigmented eyes were treated daily with O3NB at concentrations of 0.22 +/- 0.02 - 0.23 +/- 0.02 mg/L for 1 h (T1), 2 h (T2), and 3 h (T3), along with a non-treated control group. Each group was replicated three times. Hydrochemical parameters, including temperature, pH, Dissolved Oxygen (DO), Oxidation-Reduction Potential (ORP), ozone (O-3), N-NH4, H2S, N-NO2, Chemical Oxygen Demand (COD), and P-PO43-, as well as pathogenic agents (fungi), embryo morphology, and histopathology were monitored daily. The results showed that water quality in groups T1, T2, and T3 differed significantly from the control group, with higher ORP values and lower levels of COD, N-NH4, and total heterotrophic bacterial count (p < 0.05). The infection rate of Saprolegnia spp. in T1, T2, and T3 (0.89 +/- 0.8 %, 0.33 +/- 0.7 %, and 0.78 +/- 0.4 %, respectively) was significantly lower compared to the control group (5.44 +/- 1.9 %) (p < 0.05). The larval deformity rate in T1 (0.87 +/- 0.11 %) was lower than in T3 (1.63 +/- 0.25 %) (p < 0.05). Our study recommends that treatment with ozone nanobubbles (0.23 - 0.23 mg/L for 1 h) during embryogenesis, combined with maintaining dissolved oxygen at 10 mg/L using oxygen nanobubbles post-hatching, effectively reduces pathogen infections and enhances survival in rainbow trout.

Heterobothrium phamvanluci n. sp., a polyopisthocotylean monogenean infesting the gills of the half-smooth golden pufferfish Lagocephalus spadiceus, was collected off the coasts of Hai Phong and Nam Dinh provinces in the Gulf of Tonkin, Vietnam. The prevalence of infestation was 29.73 % (11/37), with an intensity range of 1-2 worms per fish. Heterobothrium phamvanluci n. sp. closely resembles H. indicum, H. victorwepeneri, and H. tonkinense, by having a male copulatory organ with 8-9 hooks. However, H. phamvanluci n. sp. can be distinguished from H. tonkinense by having fewer testes (24-40 vs. 50-100) and their position (posterior to the ovary vs. in level with it), a smaller haptor relative to body length, and a forth pair of clamps that is the smallest (vs. similar size across all pairs). Compared to H. indicum, it has a larger body length (4977 mu m vs. 3105 mu m) and a larger ratio of haptor length to body length (30 % vs. 10 %). Heterobothrium phamvanluci n. sp. differs from H. victorwepeneri by having a body length approximately three times larger (4977 mu m vs. 1094 mu m) and fewer testes (24-40, mean 28 vs. 40-50, mean 47). The 28S rDNA sequences showed that H. phamvanluci n. sp. is closely related to H. victorwepeneri, H. okamotoi, and H. tetrodonis, clustering as sibling species within the genus Heterobothrium, except H. indicum. We also propose an identification key for all known species within the genus Heterobothrium.

Nanobubble technology has demonstrated significant potential in enhancing the effectiveness of oxygen and ozone for water treatment and pathogen control. This study identifies the potential application of oxygen and ozone nanobubbles in improving the hatching efficiency of common carp eggs. Preliminary results indicated that an O3NB concentration of 0.5 mg/L was effective in treating Saprolegnia spp. However, concentrations of 0.1-0.3 mg/L caused severe gill damage and significant mortality in fish larvae. Therefore, in this study, O3NB was applied to fish embryos at 24 h post-hatch at concentrations of 0.46 +/- 0.04 to 0.55 +/- 0.06 mg/L for 1 h (T1), 2 h (T2), and 3 h (T3). Following this, from 48 h post-hatch, oxygen nanobubbles (O2NB) were used to maintain optimal oxygen levels (9.98 +/- 0.10 to 12.12 +/- 1.04 mg/L) for common carp hatching. Embryo development and the presence of pathogens were assessed at 6, 24, 48, and 72 h. The results showed that the administration of O3NB had no negative effect on the development of carp embryos. No Saprolegnia spp., Dermocystidium spp., and Fragilaria spp. were observed on embryos treated with O3NB. In the control group, infection rates were 12.67 %, 3.33 %, and 73 %, respectively. At 72 h, the T1, T2, and T3 treatments had decreased rates of gill fungus infection (13.67 +/- 5.51 %, 7.67 +/- 0.58 %, and 5.33 +/- 1.15 %, respectively) compared to the control (84.67 %, P < 0.05). The larvae survival rates after 72 h in the three treatments using O2NB and O3NB were higher compared to the control, with the T2 group achieving the highest effectiveness at 94.07 +/- 0.90 %. Our findings indicate that the application of O2NB and O3NB at appropriate developmental stages improves hatching efficiency in common carp.

Postbiotics are used in animal husbandry as dietary supplements that function as immunostimulants by activating blood cell signaling pathways, thereby inducing a heightened immune response and contributing to host protection. In this study, we evaluated the effects of a Saccharomyces cerevisiae fermentation-derived postbiotic (SCFP) on the survival rate, histopathological features, and immune responses of whiteleg shrimp (Litopenaeus vannamei) following challenge with Vibrio parahaemolyticus strain CED12.020. The experiment was conducted using three different treatment groups: (S3) shrimp fed a diet supplemented with 0.45 % SCFP for 45 days, followed by bacterial challenge; (PC) shrimp fed a non-supplemented diet for 45 days, followed by bacterial challenge; and (NC) shrimp fed a non-supplemented diet without bacterial challenge. The results demonstrated that immune parameters, including hemocyte count (THC), granulocyte count (GC), hyalinocyte count (HC), phenoloxidase activity (PO), respiratory burst activity (RES), and superoxide dismutase activity (SOD), were significantly higher in the S3 group compared to the PC and NC groups at all time points (0 h, 12 h, 24 h, 48 h, 96 h, 7 days, and 14 days) following challenge with V. parahaemolyticus (p < 0.05). The immune response of shrimp declined after 12 h, reaching the lowest point at 48 h post-infection, after which it gradually recovered and increased. The survival rate of shrimp in the S3 group after 15 days of bacterial challenge was significantly higher (82.15 %) compared to the PC group (45.94 %) (p < 0.05). These findings provide strong evidence that dietary supplementation with 0.45 % SCFP enhances the immune response and disease resistance of whiteleg shrimp against the pathogenic bacterium V. parahaemolyticus.

This study looked at how adding a postbiotic and a phytogenic supplement to the diet affects the growth and immune system of whiteleg shrimp (Litopenaeus vannamei). A 45-day feeding trial was conducted using three treatments: a control group, a postbiotic-supplemented group (Ps; 0.45% SCFP, DVAqua®), and a phytogenic-supplemented group (Ph; 0.02% plant essential oil, Biomin® P.E.P. MGE 150). All shrimp were fed a commercial diet (De Heus, codes 9802 and 9803). After 45 days of dietary supplementation, there were no statistically significant differences in growth performance indicators, including final weight (Wf), weight gain (Wg), specific growth rate (SGR), and average daily gain (ADG) among the treatment groups and the control. However, shrimp that received postbiotic and phytogenic supplements showed better results in several immune system measures, such as total hemocyte count (THC), granulocyte count (GC), hyalocyte count (HC), phenoloxidase activity (PO), respiratory burst activity (RES), and superoxide dismutase activity (SOD), compared to the control. Notably, the postbiotic group exhibited higher granulocyte density and phenoloxidase activity than the phytogenic group. These results indicate that although short-term (45 days) dietary supplementation of postbiotics and phytogenics did not improve growth performance, both additives contributed to enhancing the immune response of shrimp, with the postbiotic group (Ps; 0.45% SCFP) showing a more pronounced immunostimulatory effect. This highlights their potential as a functional feed additive that can improve the immune preparedness of whiteleg shrimp.

Nghiên cứu điều tra độc lực vi khuẩn Vibrio parahaemolyticus gây bệnh trên tôm thẻ chân trắng làm cơ sở khoa học quan trọng cho các nghiên cứu tiếp theo về đáp ứng miễn dịch và sức đề kháng của tôm đối với vi khuẩn V. parahaemolyticus. Kết quả khảo sát độc lực của 9 chủng vi khuẩn V. parahaemolyticus được phân lập trên mẫu tôm thẻ chân trắng bị bệnh đã xác định được 4 chủng (CAB16002, CAB19003, CAB25001, CED12020) mang 2 gen độc tố pirAvp và pirBvp. Cả 4 chủng đều sinh enzyme ngoại độc tố hemolysin, phospholipase và lipase. Trong đó, hoạt động của các enzyme ngoại độc tố mạnh nhất được tìm thấy ở chủng vi khuẩn V. parahaemolyticusCED12020. Chủng vi khuẩn V. parahaemolyticusCED12020 gây bệnh và gây chết tôm thẻ chân trắng ở mật độ tế bào từ 104 cfu/ml đến 107 cfu/ml với tỷ lệ gây chết tôm từ 14,17-100%. Giá trị LD50 của vi khuẩn V. parahaemolyticus CED12020 trên tôm thẻ chân trắng (5-6 g/con) được xác định là 3,0×105 cfu/ml.

Edwardsiella ictaluri is an emerging bacterial pathogen that affects farmed tilapia ( Oreochromis spp.). This study reports the arrival, establishment, and widespread findings of E. ictaluri in farmed tilapia in Vietnam. Among 26 disease outbreaks from 9 provinces in Northern Vietnam during 2019–2021, 19 outbreaks originated from imported seeds, while outbreaks in seven farms were from domestic sources. Clinically sick fish showed the appearance of numerous white spots in visceral organs, and accumulative mortality reached 30%–65%. Twenty-six representative bacterial isolates recovered from 26 disease outbreaks were identified as E. ictaluri based on a combination of phenotypic tests, genus- and species-specific polymerase chain reaction assays, 16S rRNA and gyrB sequencing, and phylogenetic analysis. All isolates harbored the same virulence gene profiles esrC, evpC, ureA-C, eseI, escD, and virD4. Antimicrobial susceptibility tests revealed that 80.8%–100% of isolates were multidrug resistant, with resistance to 4–8 antimicrobials in the groups of penicillin, macrolides, sulfonamides, amphenicols, and glycopeptides. The experimental challenge successfully induced disease that mimicked natural infection. The median lethal doses (LD ) of the tested isolates (n = 4) were 42–61 colony forming units/fish, indicating their extremely high virulence. This emerging pathogen is established and has spread to various geographical locations, causing serious impacts on farmed tilapia in northern Vietnam. It is likely that this pathogen will continue to spread through contaminated stocks (both imported and domestic sources) and persist. Thus, increased awareness, combined with biosecurity measures and emergent vaccination programs is essential to mitigate the negative impact of this emerging disease on the tilapia farming industry.

Channel catfish (Ictalurus punctatus), an introduced species in Vietnam, is widely cultured in the Northern provinces. The off-white grub disease in Channel catfish, caused by metacercariae of Dollfustrema bagarii (Digenea: Bucephalidae) lodged in internal organs, often results in heavy economic losses. Up to the present, there have been no specific guidelines for preventing and treating this disease. Here, we explore the potential treatment of infected channel catfish through the injection of Ivermectin. We evaluated the tolerance of channel catfish to the drug and determined the optimal dosage for treating off-white grubs disease. Healthy fish weighing 180–200 g received dosages of up to 3.250 mg/kg of body weight. The median lethal dose (LD50) throughout a 24-hour period was 0.808 mg/kg body weight, with a confidence interval ranging from 0.583 to 1.118 mg/kg body weight. The infected fish used for treatment testing ranged in weight from 400 to 500 g. The value for the 24-hour median effective dose (ED50) was 0.253 mg, and the appropriate therapeutic injection ranged from 0.300 to 0.700 mg per kg of body weight. Flowing the histopathological alterations, after the metacercariae were shriveled and died, the immune cells cleaned and eliminated them from fish.

Ecosystem and aquaculture in estuary areas are sensitive to climate change and severe climatic events. In this study, three environmental monitoring events were carried out on a 1800-ha clam culture area in Giao Thuy district, Nam Dinh province, Vietnam. The first monitoring was carried out in fair weather. The second and 3rd monitorings were conducted two days after the Ma On and Noru storms, respectively. The variation of water and sediment physicochemical variables, zoobenthos and plankton composition and density, and clam pathogen were investigated at five locations. In addition, long-term variations of temperature, rainfall, and sunshine duration in the area were investigated. The results illustrated the increased temperature, rainfall, and sunshine duration tendency. The clam-cultured species and activities had substantially changed. Ma On and Noru negatively impacted water quality by decreasing the water quality index by 39% and 30%, respectively. Storms decreased water salinity, alkalinity, and sediment's phosphorus, iron, lead. However, they increased water's nitrite, phosphorus, total suspended solid, phytoplankton, zooplankton density, and sediment's total nitrogen, cadimium. The total Vibrio spp. density in clam highly fluctuated between the two storm events. The effect of storm varied according to site location. Shallow and domestic wastewater adjacent sites suffered high risks of extreme temperature, salinity variation, and organic pollution.

The research was conducted from May to December 2022 in Lao Cai province. A total of 192 fish samples were collected from the traditional cultured fish group and coldwater cultured fish group. Freshoscopy method has been applied for fungal indicators, isolated culture for bacteria and PCR technique for virus indicators. The results showed that fungal agents were detected with a high infection rate in both groups of traditionally cultured fish (83.3%) and cold-water cultured fish (66.7%); Among them, more than 90% are fungus carrying Branchiomyces sp.; The remaining is Dermocystidium sp. and Aphanomyces sp, the recorded period is from May to December. Meanwhile, bacterial causes were found to be lower, infection rate of bacterial species Edwardsiella sp.; Streptococcus sp. and Aeromonas sp. recorded between 20 and 35%, especially in September and October, the infection rate is lower than other months. To limit the damage, water needs to be treated before flowing into the pond/farming tank, periodically supplement vitamin C or multivitamins to increase the fish's resistance, well control environmental factors, especially temperature, amount of ammonia and amount of organic matter in the pond.

Decapod iridescent virus 1 (DIV1) đã lưu hành tại 4 quốc gia trên thế giới bao gồm Trung Quốc, Thái Lan, vùng biển Ấn Độ Dương và Đài Loan. DIV1 được xác định nhiễm trên 15 loài, trong đó phổ biến nhất là tôm (10 loài) tiếp đến là cua (2 loài), giun nhiều tơ (2 loài) và ít nhất là luân trùng (1 loài). Các đối tượng thủy sản nhiễm DIV1 chưa thấy có báo cáo mô tả dấu hiệu bệnh lý ngoại trừ tôm chân trắng (P. vannamei) và tôm càng xanh (Macrobrachium rosenbergii). Hai loài tôm có biểu hiện chung khi nhiễm DIV1 như gan tụy teo, nhạt màu, ruột rỗng, dạ dày không có thức ăn, ngoài ra 1 số đặc điểm riêng như xuất hiện vùng trắng hình tam giác ở dưới cuống chùy (tôm càng xanh) và vỏ mềm mình hơi đỏ (tôm chân trắng). Bệnh đã được phát hiện bằng nhiều phương pháp khác nhau từ mô tả bệnh lý, mô bệnh học, sinh học phân tử, TEM hay lai tại chỗ.

Nghiên cứu được thực hiện từ tháng 9 đến tháng 12 năm 2022. Mục đích của nghiên cứu nhằm chỉ ra ảnh hưởng của ký sinh trùng lên tỷ lệ sống của cá và biện pháp trị bệnh hiệu quả. Phương pháp soi tươi đã được áp dụng để phát hiện ký sinh trùng và cá nhiễm ký sinh trùng được tắm bằng nước ngọt có bổ sung Formalin (150 ppm) trong 7-9 phút/lần, kết hợp bổ sung 20 mL Fishcare (dịch chiết từ quế và tỏi) trong 1 tạ thức ăn cho cá ăn liên tục trong 7 ngày Kết quả nghiên cứu đã chỉ ra: Amyloodinium sp. và Cryptocaryon sp. ký sinh ở cá chim vây vàng với cường độ nhiễm lần lượt tương ứng 13,1 và 21,6 trùng/thị trường. Biểu hiện bất thường được ghi nhận ở cá nhiễm ký sinh trùng bao gồm giảm ăn, bơi sát thành lồng, mang nhợt, màu sắc thân không đồng đều. Biện pháp tắm cá, thay lồng, bổ sung thảo dược tách chiết từ quế và tỏi có hiệu quả trị bệnh với tỷ lệ sống đạt > 90%. Đây cũng là báo cáo đầy đủ chi tiết đầu tiên về ảnh hưởng của Amyloodinium sp. và Cryptocaryon sp. lên tỷ lệ sống của cá chim vây vàng và kỹ thuật trị bệnh của 2 loài ký sinh trùng này.

This study aims to identify suitable density of suspended trays and care regime, which was conducted from February to November 2022 at Tay Van Boi, Lan Ha Bay, Cat Ba, Cat Hai - Hai Phong to improve growth, survival rates and helping to shorten the time for snout otter clam grow-out culture. The experiment was carried out with 3 treatments: Densities of 4, 8 and 12 trays/4 m2 combined with 3 care regimes during grow-out culture. The results showed that densities of 4 and 8 trays/4 m2 were higher growth than the remaining treatment, specifically length was from 32.9 - 36.8 mm and survival rate was over 84%, with a significant difference, compared to a density of 12 trays/4 m2 with 3 different care regimes. The results show that to increase productivity and reduce production costs and care time, a density of 8 trays/4 m2 with 3 care regimes/a culturing period should be chosen. The study has also propounded disease prevention and treatment measures for the Snout otter clam to help control the disease well and proposed solutions on farming techniques that contribute to high and sustainable economic efficiency.

The study aims to isolate, identify, and determine the pathological characteristics of Flavobacteria columnarecausing disease in tilapia cultured in Northern Vietnam. A total of 138 samples of tilapia suspected of being infected with F. columnare were collected from 34 disease outbreaks at 21 tilapia farms in Hoa Binh, Ha Nam, and Hai Duong provinces. The results showed that infected tilapia exhibited typical symptoms such as fibrous, silver gills, appearance of silvery white spots on the skin, fibrous fins. The outbreaks can occurr in tilapia farms anytime, but focusing and much damage in the winter-spring crop with accumulative mortality rates from 5-35%. A total of 87 isolates were retrieved from the fish samples; 34 representative isolates (1 isolate per outbreak) were successfully identified by phenotypic, biochemical tests, and PCR assays. Using TYES medium, the F. columnare isolates grew in yellow and rhizoid colonies after 36-48 h of culture. The bacteria were gram-negative, long filamentous, absorbed Congo red dye, produced flexirubin pigment, gliding motility, and were positive to catalase and oxidase tests. F. columnare grew well at a temperature of 25-28°C, pH 7-8 and NaCl concentration below 5‰. The present results provide critical information in developing strategies for the prevention and control of F. columnare infection in tilapia.

Widespread distribution of a highly pathogenic Edwardsiella ictaluri strain in farmed tilapia in northern Vietnam has recently been reported. The subsequent investigation noticed a disease outbreak occurred at five nearby tilapia farms with floating cages, in which the clinical signs of both edwardsiellosis and columnaris diseases were observed on the same infected fish and caused 65% to 85% fish mortality. Naturally diseased fish (n = 109) were sampled from the five infected farms for bacterial identification and conducting challenge tests. The two bacteria Edwardsiella ictaluri and Flavobacterium oreochromis were identified by a combination of biochemical tests, PCR and 16SrRNA sequencing methods. Experimental challenge tests on Nile tilapia resulted in the median lethal dose (LD50 ) of E. ictaluri and F. oreochromis at 70 CFU/fish by intraperitoneal (i.p.) injection and 3.6 × 106  CFU/mL by immersion, respectively. The experimentally co-infected challenged fish exposed to LD50 doses resulted in 83% ± 6% mortality, with the infected fish exhibiting clinical signs of both edwardsiellosis and columnaris diseases, mimicking the naturally diseased fish. This finding suggests that the co-infection of E. ictaluri and F. oreochromis may interact in a synergistic manner, to enhance the overall severity of the infection and elevates the need for efficient methods to control both pathogens.

This is the first study to examine the effect of three different cultivation methods (bottom-tray culture, suspended-tray culture, and beach/bottom culture) on the growth and survival rates of the snout otter clam, Lutraria philippinarum, after 12 months of grow-out cultivation from seed to commercial size. Analyses included weight, survival, shell size, and total fat. Although the results showed limited differences in growth among cultivation methods, survival rates were significantly different among three different culture methods. The bottom-tray cultivation method had the highest survival rate (76.5%), compared with suspended-tray cultivation (31.6%) and beach/bottom cultivation (52.5%). This demonstrates that the most suitable method for commercial snout otter clam farming is cultivation trays placed on the bottom of the substrate. Improving commercial farming of the species will support the development and expansion of aquaculture in Vietnam and elsewhere, while reducing the harvest pressure on wild populations.

Nghiên cứu được thực hiện từ tháng 9 đến tháng 12 năm 2022. Mục đích của nghiên cứu nhằm chỉ ra ảnh hưởng của ký sinh trùng lên tỷ lệ sống của cá và biện pháp trị bệnh hiệu quả. Phương pháp soi tươi đã được áp dụng để phát hiện ký sinh trùng và cá nhiễm ký sinh trùng được tắm bằng nước ngọt có bổ sung Formalin (150ppm) trong 7-9 phút/lần, kết hợp bổ sung 20mL Fishcare (dịch chiết từ quế và tỏi) trong 1 tạ thức ăn cho cá ăn liên tục trong 7 ngày Kết quả nghiên cứu đã chỉ ra: Amyloodinium sp. và Cryptocaryon sp. ký sinh ở cá chim vây vàng với cường độ nhiễm lần lượt tương ứng 13,1 và 21,6 trùng/vi trường. Biểu hiện bất thường được ghi nhận ở cá nhiễm ký sinh trùng bao gồm giảm ăn, bơi sát thành lồng, mang nhợt, màu sắc thân không đồng đều. Biện pháp tắm cá, thay lồng, bổ sung thảo dược tách chiết từ quế và tỏi có hiệu quả trị bệnh với tỷ lệ sống đạt > 90%. Đây cũng là báo cáo đầy đủ chi tiết đầu tiên về ảnh hưởng của Amyloodinium sp. và Cryptocaryon sp. lên tỷ lệ sống của cá chim vây vàng và kỹ thuật trị bệnh của 2 loài ký sinh trùng này.