Saengchan Senapin

• PhD
• Principal Investigator at National Center for Genetic Engineering and Biotechnology

Infectious spleen and kidney necrosis virus (ISKNV) has a broad host range and poses a significant threat to aquaculture species. Herein, we report two disease outbreaks in snakeskin gourami (Trichopodus pectoralis) in Thailand, marked by skin haemor- rhage, scale loss, internal organ discoloration and degeneration and a mortality exceeding 60%. Ad...

The gut microbiome is crucial in regulating nutrient metabolism, immune responses, and defense mechanisms against diseases. This study aimed to comprehensively compare bacterial community profiles within the foregut, midgut, and hindgut regions of red tilapia fish with and without streptococcosis. Red tilapia (Oreochromis nilo-ticus × Oreochromis m...

This study aims to genomically elucidate six isolates of rapidly growing non-tuberculous mycobacteria (RGM) derived from Siamese fighting fish (Betta splendens). These isolates had previously undergone phenotypic and biochemical characterization, antibiotic susceptibility testing, and in vivo virulence assessment. Initial DNA barcoding using the 16...

Background Streptococcus suis (S. suis) is an important swine and human pathogen. A recent study reported the first isolate of S. suis capable of infecting fish, designated as S. suis strain 3112. The bacterium was isolated from snakeskin gourami (Trichopodus pectoralis), an economically important fish species native to Southeast Asia, and it was p...

White spot syndrome virus (WSSV) presents a considerable peril to the aquaculture sector, leading to notable financial consequences on a global scale. Previous studies have identified hub proteins, including WSSV051 and WSSV517, as essential binding elements in the protein interaction network of WSSV. This work further investigates the functional s...

Infectious spleen and kidney necrosis virus (ISKNV) has broad host range and pose significant threat to aquaculture species. Herein, we report two disease outbreaks in snakeskin gourami (Trichopodus pectoralis) in Thailand, marked by skin hemorrhage, scale loss, internal organ necrosis, and a mortality rate exceeding 60%. Additionally, three spot g...

Scale drop disease virus (SDDV), a double-stranded DNA virus in the family Iridoviridae, has been reported widely in southeast Asian countries as a causative agent of scale drop syndrome (SDS) in Asian seabass. SDS has resulted in high mortality and significant economic losses to the aquaculture industry. This study demonstrated the use of metageno...

Piscine francisellosis, caused by the bacterium Francisella orientalis, poses a significant threat to various warm water fish. The coexistence of mosquito larvae, bacteria, and fish in aquatic ecosystems suggests the potential for interconnected pathogen/disease transmission. While mosquito larvae have been recognized as carriers of Francisella spp...

Background Scale drop disease virus (SDDV) threatens Asian seabass (Lates calcarifer) aquaculture production by causing scale drop disease (SDD) in Asian seabass. Research on the development of SDDV vaccines is missing an in-depth examination of long-term immunity and the immune reactions it provokes. This study investigated the long-term immune pr...

Scale drop disease virus (SDDV), a double-stranded DNA virus in the family Iridoviridae, has been reported widely in southeast Asian countries as a causative agent of scale drop syndrome (SDS) in Asian seabass. SDS have resulted in high mortality and significant economic losses to the aquaculture industry. This study demonstrated the use of metagen...

Asian seabass, Lates calcarifer , is an important aquatic species in mariculture. Intensive farming of this species has faced episodes of bacterial diseases, including those due to vibriosis, scale drop, and muscle necrosis disease, big belly disease, photobacteriosis, columnaris, streptococcosis, aeromoniasis, and tenacibaculosis. Vaccination is o...

• This first comprehensive genomic analysis of RGM isolates from B. splendens has led to the re-identification of certain isolates and the discovery of a new subspecies, M. mucogenicum subsp. phocaicum sp. nov. • The in silico analysis is consistent with and confirms previously reported in vitro studies on virulence and antibiotic susceptibility pr...

Background Vibrio parahaemolyticus is the leading cause of bacterial seafood-borne gastroenteritis in humans worldwide. To ensure seafood safety and to minimize the occurrence of seafood-borne diseases, early detection of total V. parahaemolyticus (pathogenic and non-pathogenic strains) and pathogenic V. parahaemolyticus ( tdh ⁺ and/or trh1 ⁺ and/o...

To investigate early immune responses and explore the optimal vaccination periods, Nile tilapia at 1, 7, 14, 21, 28, 35, and 42 days after yolk sac collapse (DAYC) were immersed in formalin-killed Streptococcus agalactiae vaccine (FKV-SA). A specific IgM was first detected via ELISA in the 21 DAYC larvae (0.108 g) at 336 h after vaccination (hav),...

Betta splendens, a valuable ornamental fish species, is particularly susceptible to mycobacteriosis which poses a challenge to the sustainability of its culture and trade. Since there are no effective treatments for the disease, betta fish farms must take rigorous preventive measures. This study investigated the efficacy of ozone nanobub-bles (NB-O...

Tilapia lake virus (TiLV) is a highly contagious viral pathogen that affects tilapia, a globally significant and affordable source of fish protein. To prevent the introduction and spread of TiLV and its impact, there is an urgent need for increased surveillance, improved biosecurity measures, and continuous development of effective diagnostic and r...

Mycobacteriosis, a chronic progressive disease in fish caused by Mycobacterium spp., is typically characterized by granulomatous lesions that illustrate its harmful pathogenesis. This study was initiated to understand the progression of mycobacteriosis in Siamese fighting fish (Betta splendens) through various transmission modes. Experimental infec...

To investigate the early immune responses and explore the optimal vaccination periods, Nile tilapia at 1, 7, 14, 21, 28, 35, and 42 days after yolk sac collapse (DAYC), were immersed in formalin-killed Streptococcus agalactiae vaccine (FKV-SA). The results found that specific IgM by ELISA in 21 DAYC (0.108 g) was first detected at 336 h after vacci...

Streptococcus iniae is a bacterial pathogen that causes streptococcosis, leading to significant losses in fish aquaculture globally. This study reported a newly developed probe‐based quantitative polymerase chain reaction (qPCR) method for the detection of S. iniae . The primers and probes were designed to target the lactate oxidase gene. The optim...

Siamese fighting fish (Betta splendens) play an important role in the global aquarium trade, but their susceptibility to mycobacteriosis could challenge the long-term sustainability of the industry. Thus, this study aimed to characterize rapidly growing non-tuberculous mycobacteria (RGM) isolated from the fish and to investigate their pathogenicity...

The treatment of Nile tilapia with ozone nanobubbles (ONb) prior to vaccination with an immersible heat-killed Streptococcus agalactiae ( Sa ) vaccine has been reported to modulate and enhance both innate and specific immunity. The efficacy of this novel vaccination strategy is explored further in field trials. This strategy involved a short-term t...

Background Tilapia aquaculture faces significant threats posed by four prominent pathogens: tilapia lake virus (TiLV), infectious spleen and kidney necrosis virus (ISKNV), Francisella orientalis , and Streptococcus agalactiae . Currently, employed molecular diagnostic methods for these pathogens rely on multiple singleplex PCR reactions, which are...

Early disease prevention by vaccination requires understanding when fry fish develop specific immunity to a given pathogen. In this research, we explored the immune responses of Asian seabass (Lates calcarifer) at the stages of 35- and 42- days post-hatching (dph) to an immersive heat-killed Streptococcus iniae (Si) vaccine to determine whether fis...

Nervous necrosis virus (NNV) has spread throughout the world, affecting more than 120 freshwater and marine fish species. While vaccination effectively prevents disease outbreaks, the difficulty of producing sufficient viruses using cell lines continues to be a significant disadvantage for producing inactivated vaccines. This study, therefore, expl...

Tilapia lake virus (TiLV) is a highly contagious viral disease that affects tilapia, a globally significant and affordable source of fish protein. To combat the introduction and spread of TiLV and its impact, there is an urgent need for increased surveillance, improved biosecurity measures, and continuous development of effective diagnostic and seq...

Here, we report on two cases of disease with scattered, pronounced sub-epithelial swellings in the body of cultured snakeskin gourami (Trichopodus pectoralis) fingerlings from two independent farm sites. Locally, the condition is known colloquially as “lumpy skin disease”. The abnormal raised distortions of the skin were due to encysted metacercari...

Tilapia is an affordable protein source farmed in over 140 countries with the majority of production in low-and middle-income countries. Intensification of tilapia farming has exacerbated losses caused by emerging and re-emerging infectious diseases. Disease diagnostics play a crucial role in biosecurity and health management to mitigate disease lo...

Abstract: Juvenile Asian seabass (Lates calcarifer) (body weight 10 ± 0.7 g) were intraperitoneally injected with 10 12 CFU fish −1 of formalin-killed Streptococcus iniae. The protective efficacy of the vaccine on survival and infection rate was assessed upon challenge at 4, 8, 12, 20, and 28 weeks post-vaccination. The results revealed that the ch...

A purported parvovirus producing circular, eosinophilic inclusions in the nuclei of tubule epithelial cells of the hepatopancreas (HP) of the giant freshwater prawn Macrobrachium rosenbergii (Mr) was first reported from Malaysia in 1990. In 2009, similar inclusions in Mr from Thailand were confirmed to contain single-stranded DNA (ssDNA). In 2021,...

Nervous necrosis virus (NNV) has spread throughout the world, affecting more than 120 freshwater and marine fish species. While vaccination effectively prevents disease outbreaks, the difficulty of producing sufficient viruses using cell lines continues to be a significant disadvantage for producing inactivated vaccines. This study, therefore, expl...

Tilapia lake virus (TiLV) or Tilapia tilapinevirus is a highly contagious pathogen that causes severe symptoms and massive mortalities in tilapia, affecting numerous tilapia-farming communities across the continents. Though TiLV has grown into a serious threat that could undermine the aquaculture-based economy and global food security, effective th...

Infectious spleen and kidney necrosis virus (ISKNV) is one of the detrimental viruses causing economic losses in several fish species including Asian seabass (Lates calcarifer). In this study, monoclonal antibodies specific to major capsid protein (MCP) of ISKNV were generated. The MCP encoding gene of ISKNV genotype II was cloned into pGEX-6P-1 an...

A purported parvovirus producing circular, eosinophilic inclusions in the nuclei of tubule epithelial cells of the hepatopancreas (HP) of the giant freshwater prawn Macrobrachium rosenbergii (Mr) was first reported from Malaysia in 1994. In 2009, similar inclusions in Mr from Thailand were confirmed to contain single-stranded DNA (ssDNA). In 2021,...

Nervous necrosis virus (NNV) is a deadly virus that affects >120 fish species worldwide, but there is little information about it in Thailand. In August 2019, a population of pearl gentian grouper fry imported to Thailand experienced mass mortality. The diseased fish exhibited darkening, floating on the water surface, ‘sleepy behaviour’, and errati...

Tilapia parvovirus (TiPV) is an emerging virus reportedly associated with disease and mortality in farmed tilapia. Although previous descriptions of histopathological changes are available, the lesions reported in these are not pathognomonic. Here, we report Cowdry type A inclusion bodies (CAIB) in the pancreas as a diagnostic histopathological fea...

The objective of this study was to determine the causative agent of an outbreak with clinical signs similar to those of piscine streptococcosis in farmed snakeskin gourami ( Trichopodus pectoralis ). Initial microscopic examination revealed the predominance of a Gram-positive, cocci bacteria in the brain and kidney of the diseased fish. This bacter...

Background Tilapia tilapinevirus , also known as tilapia lake virus (TiLV), is a significant virus that is responsible for the die-off of farmed tilapia across the globe. The detection and quantification of the virus using environmental RNA (eRNA) from pond water samples represents a potentially non-invasive and routine strategy for monitoring path...

The objective of this study was to determine the causative agent of an outbreak with clinical signs similar to those of piscine streptococcosis in farmed snakeskin gourami ( Trichopodus pectoralis ). Initial microscopic examination revealed the predominance of a Gram-positive, cocci bacteria in the brain and kidney of the diseased fish. This bacter...

Tilapia parvovirus (TiPV) is an emerging virus reportedly associated with disease and mortality in farmed tilapia. Although previous descriptions of histopathological changes are available, the lesions reported in these are not pathognomonic. Here, we report Cowdry type A inclusion bodies (CAIB) in the pancreas as a diagnostic histopathological fea...

Nanobubble technology has shown appealing technical benefits and potential applications in aquaculture. We recently found that treatment with ozone nanobubbles (NB–O3) activated expression of several immune-related genes leading to effective response to subsequent exposure to fish pathogens. In this study, we investigated whether pre-treatment of N...

Edwardsiella ictaluri is a Gram‐negative bacterium that has been reported to be disease causing in several economic fish including Nile tilapia. Here, immunoproteomic identification found that outer membrane protein A (OmpA) could react with serum from fish naturally infected with E. ictaluri. The expression and production of recombinant OmpA prote...

Nervous necrosis virus (NNV) is a deadly virus that affects more than 120 fish species worldwide, but there is little information about it in Thailand. In August 2019, a population of pearl gentian grouper fry imported to Thailand experienced mass mortality. The diseased fish exhibited darkening, floating on the water surface, ‘sleepy behaviour’, a...

Tilapia lake virus (TiLV), a major pathogen of farmed tilapia, is known to be vertically transmitted. Here, we hypothesize that Nile tilapia (Oreochromis niloticus) broodstock immunized with a TiLV inactivated vaccine can mount a protective antibody response and passively transfer maternal antibodies to their fertilized eggs and larvae. To test thi...

Injection of ozone nanobubbles into water reduces bacterial load, improves dissolved oxygen, and modulates the fish innate immune system. Little is known about the effect that nanobubble treatment has on the concentration of viruses in water. This study, investigated the disinfection impact of oxygen and ozone nanobubbles (NB-O2 and NB-O3) on an Ae...

Tilapia lake virus (TiLV), a major pathogen of farmed tilapia, is known to be vertically transmitted. Here, we hypothesize that Nile tilapia (Oreochromis niloticus) broodstock immunized with a TiLV inactivated vaccine can mount a protective antibody response and passively transfer maternal antibodies to their fertilized eggs and larvae. To test thi...

Nanobubble technology has shown appealing technical benefits and potential applications in aquaculture. We recently found that treatment with ozone nanobubbles (NB-O 3 ) activated expression of several immune-related genes leading to effective response to subsequent exposure to fish pathogens. In this study, we investigated whether pre-treatment of...

Myxosporean parasites Kudoa spp. have been reported in several marine fish species worldwide. However, little is known about the contamination of these parasites in raw fish in Southeast Asia where consumption demand of uncooked fish is increasing. In 2019, occurrence of several cases of raw yellowfin tuna (Thunnus albacares) obtained from retail s...

Tilapia Lake Virus Disease (TiLVD) is caused by Tilapia Lake Virus (TiLV), and it has a cumulative mortality rate of up to 90% in Nile tilapia (Oreochromis niloticus). TiLV is a negative enveloped single-stranded RNA virus with 10 genomic segments. Segment 5 (S5) and segment 6 (S6) were predicted to include a signaling peptide, suggesting that the...

Scale drop disease virus (SDDV) is a major pathogen of Asian sea bass that has emerged in many countries across the Asia Pacific since 1992 and carries the potential to cause drastic economic losses to the aquaculture sector. The lack of an approved vaccine for SDDV necessitates timely prevention as the first line of defence against the disease, bu...

Tilapia tilapinevirus (also known as tilapia lake virus, TiLV) is considered to be a new threat to the global tilapia industry. The objective of this study was to develop simple cell culture-based heat-killed (HKV) and formalin-killed (FKV) vaccines for the prevention of disease caused by TiLV. The fish were immunized with 100 µl of either HKV or F...

Edwardsiella ictaluri infects several fish species and protection of the all the susceptible fish hosts from the pathogen using a monovalent vaccine is impossible because the species is composed of host‐based genotypes that are genetic, serological and antigenic heterogenous. Here, immunoinformatic approach was employed to design a cross‐immunogeni...

Bacteriophage (phage) is considered as one of the alternatives to antibiotics and an environmentally friendly approach to tackle antimicrobial resistance (AMR) in aquaculture. Here, we reported isolation, morphology and genomic characterizations of a newly isolated lytic phage, designated pAh6.2TG. Host range and stability of pAh6.2TG in different...

Sixteen countries, including Bangladesh, have reported the presence of tilapia lake virus (TiLV), an emerging tilapia pathogen. Fish polyculture is a common farming practice in Bangladesh. Some unusual mortalities reported in species co‐cultivated with TiLV‐infected tilapia led us to investigate whether any of the co‐cultivated species would also t...

Tilapia tilapinevirus (also known as tilapia lake virus, TiLV) is an important virus responsible for die-off of farmed tilapia globally. Detection and quantification of the virus from environmental DNA/RNA (eDNA/eRNA) using pond water represents a potential, noninvasive routine approach for pathogen monitoring and early disease forecasting in aquac...

Marine farming of barramundi (Lates calcarifer) in Southeast Asia is currently severely affected by viral diseases. To better understand the biological implications and gene expression response of barramundi in commercial farming conditions during a disease outbreak, the presence of pathogens, comparative RNAseq, and histopathology targeting multip...

Bacteriophage is considered an alternative to antibiotics and environmentally friendly approach to tackle antimicrobial resistance (AMR) in aquaculture. Here, we reported isolation, morphology and genomic characterizations of a newly isolated lytic bacteriophage, designated pAh6.2TG. Host range and stability of pAh6.2TG in different environmental c...

Infectious diseases represent one of the major challenges to sustainable aquaculture production. Rapid, accurate diagnosis and genotyping of emerging pathogens during early-suspected disease cases is critical to facilitate timely response to deploy adequate control measures and prevent or reduce spread. Currently, most laboratories use PCR to ampli...

Tilapia tilapinevirus (also known as tilapia lake virus, TiLV) is considered to be a new threat to the global tilapia industry. The objective of this study was to develop simple cell culture-based heat-killed (HKV) and formalin-killed (FKV) vaccines for the prevention of disease caused by TiLV. The fish were immunized with 100 μL of either HKV or F...

White spot syndrome virus (WSSV) is the most virulent pathogen causing high mortality and economic loss in shrimp aquaculture and various crustaceans. Therefore, the understanding of molecular mechanisms of WSSV infection is important to develop effective therapeutics to control the spread of this viral disease. In a previous study, we found that V...

A rapid increase in multi‐drug‐resistant (MDR) bacteria in aquaculture highlights the risk of production losses due to diseases and potential public health concerns. Previously, we reported that ozone nanobubbles (NB‐O3) were effective at reducing concentrations of pathogenic bacteria in water and modulating fish immunity against pathogens; however...

Tilapia is one of the major aquaculture species with a global economic significance. Despite a high scale of production worldwide, mortality in many tilapia cultures has recently become a problem concerned with not only intensive farming but also the prevalence of infectious pathogens. Tilapia lake virus (TiLV) has emerged as a serious single‐stran...

Scale drop disease virus (SDDV) is one of the most important pathogens that causes scale drop disease (SDD) in Asian sea bass (Lates calcarifer). The outbreaks of this disease are one of the factors causing substantial losses in Asian sea bass aquaculture. In this study, the uracil-DNA glycosylase (UDG)-supplemented cross-priming amplification (UCP...

A new species of small freshwater prawn in the Macrobrachium pilimanus species group was found in the upper southern peninsula of Thailand. The prawns in this group exhibit velvet setae on the telopodites of the second pereiopods. The new species, named M. prachuapense sp. nov., is endemic to Thailand. It has several characteristics that make it st...

Edwardsiella ictaluri has been considered an important threat for catfish aquaculture industry for more than 4 decades and an emerging pathogen of farmed tilapia but only 9 sequenced genomes were publicly available. We hereby report two new complete genomes of E. ictaluri originated from diseased hybrid red tilapia (Oreochromis sp.) and striped cat...

Accuracy is crucial for polymerase chain reaction (PCR) diagnostic laboratories. We noticed inconsistent PCR results or false negatives that sometimes occurred when changing commercial brand of Taq DNA polymerase enzyme. Here, we tested 6 primer sets specific for 3 important aquaculture viruses (scale drop disease virus (SDDV), tilapia lake virus (...

Infectious diseases represent one of the major challenges to sustainable aquaculture production. Rapid and accurate diagnosis of emerging pathogens during early-suspected disease cases is critical to facilitate timely response to deploy adequate control measures and prevent or reduce spread. Currently, most laboratories use PCR to amplify partial p...

Tilapia tilapinevirus or tilapia lake virus (TiLV) is an emerging virus that inflicts significant mortality on farmed tilapia globally. Previous studies reported detection of the virus in multiple organs of the infected fish; however, little is known about the in‐depth localization of the virus in the central nervous system. Herein, we determined t...

Multidrug-resistant (MDR) bacteria has rapidly increased in aquaculture, which highlights the risk of production losses due to diseases and potential public health concerns. Previously, we reported that ozone nanobubbles (NB-O 3 ) were effective at reducing concentrations of pathogenic bacteria in water and modulating fish immunity against pathogen...

Ozone nanobubble (NB-O3) is a promising technology for improving dissolved oxygen and reducing bacterial concentration in aquaculture systems. Here, we investigated the effects of NB-O3 on the innate immunity of fish by monitoring the expression levels of nonspecific immune-related genes (IL-1β, IL-2β, TNF-α), heat-shock protein genes (HSP70, HSP90...

Tilapia tilapinevirus or tilapia lake virus (TiLV) is an emerging virus that inflicts significant mortality on farmed tilapia globally. Previous studies reported detection of the virus in multiple organs of the infected fish; however, little is known about the in-depth localization of the virus in the central nervous system. Herein, we determined t...

A unique strain of Vibrio harveyi is the causative agent of scale drop and muscle necrosis disease (SDMND) in Asian sea bass (Lates calcarifer). This study investigated the protein profiles of SDMND-causing Vibrio harveyi isolates compared to the reference V. harveyi ATCC 14126 strain. A distinct protein band of 33 kDa, namely HP33, found from only...

High concentrations of certain pathogenic bacteria in water usually results in outbreaks of bacterial diseases in farmed fish. Here, we explore the potential application of an emerging nanobubble technology in freshwater aquaculture, specifically aimed to reduce the concentrations of pathogenic fish bacteria in freshwater, and assess whether nanobu...

Asian seabass, Lates calcarifer farming in Southeast Asia, encounters serious disease challenges caused by Streptococcus agalactiae and Streptococcus iniae. However, a vaccine for disease prevention is not yet available. In this study, we investigated the mucosal and systemic antibody (IgM) response kinetics of the Asian seabass following primary i...

A small wild prawn of the genus Macrobrachium, found in Chiang Rai Province, Northern Thailand has some morphological features resembling four other closely related species, M. lanchesteri, M. peguense, M. kunjuramani, and M. chainatense. However, it is distinguishable from the above species in terms of distinctive golden colored antennules; number...

Non‐destructive sampling methods offer practical advantages to detection and monitoring of viral pathogens in economically important farmed fish and broodstock. Here, we investigated whether blood, mucus and fin can be used as non‐lethal sample sources for detection of scale drop disease virus (SDDV) in farmed Asian sea bass, Lates calcarifer. Dete...

Retrospective diagnosis of a bacterial collection (n = 31) originated from five farms reportedly affected by early mortality syndrome (EMS) in Southeast Asia in 2016 revealed that 9/31 isolates from two farms tested positive for V. parahaemolyticus causing acute hepatopancreatic necrosis disease (VPAHPND). Molecular analysis of the 22 remaining iso...

The gene of RNA viruses, encoding RNA-directed RNA polymerase (RdRp) is relatively conserved due to its crucial function in viral genome replication and transcription making it a useful target for genetic diversity study and PCR detection. In this study, we investigated the genetic diversity of 21 tilapia lake virus (TiLV) genome segment 1 sequence...