Aims: Aquaculture has grown tremendously in Malaysia over the past decades. However, guaranteeing aquaculture sustainability is a big challenge in terms of maintaining continuous output with a safe environment. Furthermore, the cultured species should be free from antibiotic resistance bacterial and antibiotic residue. This study aimed to monitor the existence and prevalence of antibiotic resistant bacteria associated with aquaculture farms in Sarawak. Methodology and results: Samples of water, sediment and fish were collected from five aquaculture farms within Sarawak. The samples were plated on trypticase soy agar and incubated at 28 °C for 24 h. A total of 204 bacterial isolates were isolated and analysed by (GTG)5-fingerprinting to determine genetic similarity among the bacterial isolates, so that representatives could be selected from similar clonal isolates. Based on the (GTG)5 profiles, 50 representative isolates were chosen for species identification using 16S rRNA sequencing. The identified bacteria were tested against 25 antibiotics using standard disk diffusion method. The 16S rRNA analysis revealed that the isolates constitute of 14 genera of bacteria including Bacillus (38%), Exiguobacterium (16%), Enterobacter (14%), Aeromonas (6%), Acinetobacter (4%), Citrobacter (4%), Staphylococcus (4%), Achromobacter (2%), Chitinophaga (2%), Fictibacillus (2%), Plesiomonas (2%), Pseudomonas (2%), Pseudoxanthomonas (2%) and Stenotrophomonas (2%). The antibiotic resistance analysis revealed that the highest percentage of resistance was recorded against streptomycin (75.0%), followed by ampicillin (66.0%), ceftriaxone (50.0%), rifampin (43.3%), aztreonam (36.8%) and ceftazidime (31.6%). Resistance to more than two antibiotics was observed in 40.0% of isolates with an overall multiple antibiotic resistant (MAR) index ranging from 0 to 0.79. Conclusion, significant and impact of study The variability of antibiotic resistance patterns exhibited by different bacterial species suggests a dependence on selective pressures exhibited in different geographical locations. Our results show that the occurrence of MAR bacteria in an aquaculture environment with unknown history of antibiotics usage in the aquaculture system is possible, indicating a need to continuously monitor the presence of antibiotic resistant bacteria in the aquaculture system.
Drug Resistance, Microbial ; Aquaculture ; Malaysia

Ecdysis is a common phenomenon that happens throughout the life phase of the giant freshwater prawn Macrobrachium rosenbergii. It is vital to better understand the correlation between cannibalism and biochemical compound that exists during the moulting process. The objective of the present study was to determine the amino acid profile released by M. rosenbergii during the ecdysis process that promotes cannibalism. To accomplish this, changes in amino acid levels (total amino acid (TAA) and free amino acid (FAA)) of tissue muscle, exoskeleton, and sample water of culture medium from the moulting (E-stage) and non-moulting (C-stage) prawns were analysed using high-performance liquid chromatography (HPLC). Comparison study revealed that among the TAA compounds, proline and sarcosine of tissues from moulting prawn were found at the highest levels. The level of FAA from water that contains moulting prawns (E-stage) was dominated by tryptophan and proline. Significant values obtained in the present study suggested that these amino acid compounds act as a chemical cue to promote cannibalism in M. rosenbergii during ecdysis. The knowledge of compositions and compounds that were released during the moulting process should be helpful for better understanding of the mechanism and chemical cues that play roles on triggering cannibalism, and also for future dietary manipulation to improve feeding efficiencies and feeding management, which indirectly impacts productivity and profitability.
Amino Acids/chemistry* ; Animals ; Aquaculture ; Cannibalism ; Chromatography, High Pressure Liquid ; Feeding Behavior ; Fresh Water ; Malaysia ; Molting ; Palaemonidae/physiology* ; Proline/chemistry* ; Tryptophan/chemistry*

Background and Objective: Microorganisms, including bacteria, serve as major players in various processes affecting both the quality of aquatic sediment as well as the fate of pollutants released into such matrix. This study, evaluated the similarity in bacterial community structure between sediments collected from aquaculture and non aquaculture sites of a tropical lake. Describing and comparing the bacterial community present in each site may provide clues on the impact of aquaculture practices on aquatic ecosystems.
Methodology: Microbial DNA was extracted using PowerSoil® DNA Isolation Kit for all sediment samples. DNA isolates were used as template in the analysis of the hypervariable region of 16S rDNA through nested polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE). Excised representative 16S rDNA DGGE bands were sequenced and identified through BLAST analysis.
Results: Based on the generated mean Dice similarity coefficient of 57.77%, the bacterial community structure between aquaculture and non-aquaculture sediments was highly similar but certain taxa were found unique for each site. Bacteria belonging to Proteobacteria and Firmicutes dominated the aquaculture sediments while Proteobacteria, Firmicutes, and Chloroflexi dominated the non-aquaculture sediments. Certain physicochemical parameters operating in the two sites may have influenced the shift in representative microbes. Shewanella baltica and Trichococcus sp. were found only in aquaculture sediment owing to their ability to tolerate quantities of ammonia and high organic matter from their environment.
Conclusions: This study described the applicability of 16S rDNA PCR-DGGE as a culture-independent technique for describing and comparing the similarity between bacterial communities in sediment. Based on the generated similarity index, the bacterial community between aquaculture and non-aquaculture sediments of Taal Lake was highly similar but interestingly, harbored unique bacterial populations as seen in the DGGE profiles. The shift in dominant taxa and unique representatives per site may have been influenced by certain differences between each site's physico-chemical parameters.

Many members of the Saprolegniales (Oomycete) cause mycoses and disorders of fishes, of which Achlya and Saprolegnia are most ubiquitous genera worldwide. During a survey of the diversity of freshwater oomycetes in Korea, we collected seven isolates of Achlya, for which morphological and molecular phylogenetic analyses enabled them to identify as Achlya americana and Achlya bisexualis. In Korea, only a species of Achlya, A. prolifera, has been previously found to cause seedling rot on rice (Oryza sativa), but none of the two species have been reported yet. Importantly, A. bisexualis was isolated from a live fish, namely rice fish (Oryzias sinensis), as well as freshwater, and this is the first report of Achlya-causing mycoses on freshwater fishes in Korea. The presence of A. americana and A. bisexualis on live fish in Korea should be closely monitored, as considering the well-known broad infectivity of these species it has the potential to cause an important emerging disease on aquaculture industry.
Achlya ; Aquaculture ; Fishes ; Fresh Water ; Korea ; Mycoses ; Oomycetes ; Saprolegnia ; Seedlings

As one of the most common pathogens in aquatic animals, Aeromonas hydrophila exhibits a wide range of pathogenicity. Due to factors like unreasonable use of antibiotics and horizontal gene transfer mediated by plasmids, many resistant strains of Aeromonas hydrophila were isolated from ready-to-eat seafood products in retail markets, supermarkets and restaurants. These strains carry many resistance genes. Therefore, it is essential to explore the key control points, and seek for prevention and control strategies so as to effectively alleviate antibiotic resistance. We review here the prevalence of drug resistance of Aeromonas hydrophila in China, and its main infection and resistance mechanisms, and the main means and strategies for reducing and preventing drug resistance. We also address further research directions and focus on drug resistance in Aeromonas hydrophila of the aquatic product.
Aeromonas hydrophila ; drug effects ; Animals ; Anti-Bacterial Agents ; pharmacology ; China ; epidemiology ; Drug Resistance, Bacterial ; Fish Diseases ; epidemiology ; microbiology ; Fisheries ; Fishes ; Gram-Negative Bacterial Infections ; epidemiology ; microbiology ; Research

By activity-guided fractionation, gliotoxin was isolated as an antibacterial metabolite of the fungus Penicillium decumbens which was derived from the jellyfish Nemopilema nomurai. Gliotoxin was further evaluated for antibacterial activity against several piscine and human MDR (multidrug resistance) pathogens. Gliotoxin showed significant antibacterial activity against Gram-positive piscine pathogens such as Streptococcus iniae FP5228, Streptococcus iniae FP3187, Streptococcus parauberis FP3287, Streptococcus parauberis SPOF3K, S. parauberis KSP28, and Lactococcus garvieae FP5245. Gliotoxin showed strong activity especially against S. parauberis SPOF3K and S. iniae FP5228, which are resistant to oxytetracycline. It is noteworthy that gliotoxin effectively suppressed streptococci which are the major pathogens for piscine infection and mortality in aquaculture industry. Gliotoxin also showed strong antibacterial activity against multidrug-resistant human pathogens (MDR) including Enterococcus faecium 5270 and MRSA (methicillin-resistant Staphylococcus aureus) 3089.
Aquaculture ; Enterococcus faecium ; Fungi ; Gliotoxin ; Humans ; Lactococcus ; Methicillin-Resistant Staphylococcus aureus ; Mortality ; Oxytetracycline ; Penicillium ; Staphylococcus ; Streptococcus

Mycobacterium marinum infection in humans occurs mainly as a granulomatous infection after exposure of traumatized skin to contaminated water. It is usually confined to the skin and soft tissue. Disseminated disease involving other organs rarely occurs in immunocompetent patients. Here, we report a case of disseminated M. marinum infection involving not only the cutaneous tissue, but also the lung of a male patient with uncontrolled diabetes and a previous history of steroid injection who was employed by a deep-water fishery.
Diabetes Mellitus* ; Fisheries ; Humans ; Lung* ; Male ; Mycobacterium marinum* ; Mycobacterium* ; Skin ; Steroids ; Water

Mycobacterium marinum infection in humans occurs mainly as a granulomatous infection after exposure of traumatized skin to contaminated water. It is usually confined to the skin and soft tissue. Disseminated disease involving other organs rarely occurs in immunocompetent patients. Here, we report a case of disseminated M. marinum infection involving not only the cutaneous tissue, but also the lung of a male patient with uncontrolled diabetes and a previous history of steroid injection who was employed by a deep-water fishery.
Diabetes Mellitus* ; Fisheries ; Humans ; Lung* ; Male ; Mycobacterium marinum* ; Mycobacterium* ; Skin ; Steroids ; Water

OBJECTIVES: The purpose of this study was to compare the diabetic management indicators between agriculture, forestry, and fishery workers (AFF) and other occupational adults (non-AFF) in community-dwelling diabetes. METHODS: The study population consisted of 22,127 diabetic population ≥19 years who participated in the 2015 Community Health Survey. Chi-square test and logistic regression analysis was used to compare the diabetic management indicators between AFF and non-AFF. Socioeconomic characteristics such as age, gender, education level, monthly household income, National Basic Livelihood Security status, and marital status was sequentially adjusted. RESULTS: Among total diabetic population, 3,712 people (16.8%) was AFF and 18,415 people (83.2%) was non-AFF. The fully-adjusted odds ratio [OR] (95% confidence interval [CI]) of current non-medical treatment (0.72, 0.66–0.79), measurement of hemoglobin A1c (0.61, 0.55–0.67), screening for diabetic retinopathy (0.76, 0.70–0.83), screening for diabetic nephropathy (0.75, 0.70–0.81), non-alcoholic or moderate drinking (0.70, 0.64–0.78), nutrition label reading (0.83, 0.71–0.98), low salt preference (0.85, 0.78–0.93), dental examination (0.60, 0.54–0.66), scaling experience (0.84, 0.77–0.93), regular toothbrushing (0.66, 0.58–0.76), and diabetes management education (0.84, 0.77–0.92) was significantly lower in AFF compared to non-AFF. In contrast, the fully-adjusted OR (95% CI) of AFF's low stress level (1.39, 1.26–1.52) and adequate sleep duration (1.22, 1.13–1.32) was significantly higher than non-AFF, which are better indicators of diabetic management in AFF. CONCLUSIONS: Overall, the level of diabetes management of AFF was not as good as that of non-AFF. In order to improve the level of diabetes management of AFF, a delicate diabetes intervention strategy considering the occupational characteristics of AFF will be needed.
Adult ; Agriculture* ; Diabetes Mellitus ; Diabetic Nephropathies ; Diabetic Retinopathy ; Disease Management ; Drinking ; Education ; Family Characteristics ; Farmers ; Fisheries* ; Forestry* ; Health Surveys ; Humans ; Logistic Models ; Marital Status ; Mass Screening ; Odds Ratio ; Toothbrushing

OBJECTIVES: Confirmation of Kudoa septempunctata (K. septempunctata) as the pathogenic agent causing acute food poisoning remains under debate owing to inconsistencies in the reproducibility of experimental evidence. Higher intake of olive flounder infected with K. septempunctata would result in increased diagnosis of food poisoning by K. septempunctata, if the latter was one of the causal agents of acute food poisoning. The aim was to evaluate the relationship between the shipping amount of olive flounder aquacultured from Jejudo and the incidence of K. septempunctata food poisoning in 2015, Korea. METHODS: Data of shipping amounts between March 2014 and February 2016 and of monthly reported events of Kudoa food poisoning were taken from Jejudo Fish-Culture Fisheries Cooperatives and Korea Centers for Disease Control and Prevention, respectively. Non-parametric correlation analyses were conducted. RESULTS: Shipping amounts indicated the seasonal changes according to variation of consumption. Spearman's rho and Kendall's tau-a between the monthly shipping amounts and the reported events in 2015 were 0.39 (p=0.21) and 0.27 (p=0.20), respectively. CONCLUSIONS: An independent relationship was noted between the shipping amount and the reported events, which contrasted with the claim that the virulence of K. septempunctata caused acute food poisoning.
Bias (Epidemiology) ; Centers for Disease Control and Prevention (U.S.) ; Diagnosis ; Fisheries ; Flounder* ; Food Parasitology ; Foodborne Diseases* ; Incidence ; Intestinal Diseases, Parasitic ; Jeju-do* ; Korea* ; Myxozoa ; Olea* ; Seasons ; Ships* ; Virulence