Vibrio is the most common bacterium associated with diseases in crustaceans. Outbreaks of vibriosis pose a serious threat to shrimp production. Therefore, antibiotics are commonly used as preventative and therapeutic measures. Unfortunately, improper use of antibiotics leads to antibiotic resistance. Nevertheless, information on the occurrence of Vibrio spp. and antibiotic use in shrimp, particularly in Malaysia, is minimal. This study aimed to provide information on the occurrence of Vibrio spp., its status of antibiotic resistance and the plasmid profiles of Vibrio spp. isolated from cultured shrimp in Peninsular Malaysia. Shrimp were sampled from seven farms that were located in different geographical regions of Peninsular Malaysia. According to the observations, 85% of the shrimp were healthy, whereas 15% were unhealthy. Subsequently, 225 presumptive Vibrio isolates were subjected to biochemical tests and molecular detection using the pyrH gene. The isolates were also tested for antibiotic susceptibility against 16 antibiotics and were subjected to plasmid profiling. Eventually, 13 different Vibrio spp. were successfully isolated and characterized using the pyrH gene. They were the following: V. parahaemolyticus (55%), V. communis (9%), V. campbellii (8%), V. owensii (7%), V. rotiferianus (5%), Vibrio spp. (4%), V. alginolyticus (3%), V. brasiliensis (2%), V. natriegens (2%), V. xuii (1%), V. harveyi (1%), V. hepatarius (0.4%) and P. damselae (3%). Antibiotic susceptibility profiles revealed that all isolates were resistant to penicillin G (100%), but susceptible to norfloxacin (96%). Furthermore, 16% of the isolates revealed MAR of less than 0.2, while 84% were greater than 0.2. A total of 125 isolates harbored plasmids with molecular weights between 1.0 and above 10 kb, detected among the resistant isolates. The resistant isolates were mediated by both chromosomal and plasmid factors. These findings support the use of surveillance data on the emerging patterns of antimicrobial-resistance and plasmid profiles of Vibrio spp. in shrimp farms. The findings from this study can be used to develop a better disease management strategy for shrimp farming.

We reported the first complete mitochondrial genome of the Scarlet Fighting Fish, Betta coccina (Vierke, 1979), a species of concern due to its vulnerable status. Genome skimming was performed on a specimen collected from Johor, Malaysia to recover its mitochondrial genome. The assembled complete mitogenome is 16,502 bp in size, comprising the standard set of 13 protein-coding genes, 22 tRNAs, and two rRNAs, typical of most vertebrates mitogenome. Phylogenetic analysis was conducted using the whole mitogenome of B. coccina and four publicly available mitogenomes of Betta spp. Our analysis revealed that the B. coccina currently occupied a basal position relative to other Betta spp. with maximal support value. Our results provide valuable insights for both evolutionary studies and genetic conservation efforts of B. coccina and its related species.

Pangasiids are an economically significant group of catfish, and many pangasiids are threatened in the wild from anthropogenic pressures, including increases in fishing pressure, habitat degradation, and improperly managed aquaculture practices. This study demonstrates the usage of DNA barcoding of the Cytochrome Oxidase subunit I (COI) gene as an identification tool in detecting potentially threatening invasive pangasiid species by establishing the diversity and phylogenetic relationship of Pangasiidae catfishes in Peninsular Malaysia. A neighbour-joining (NJ) dendrogram (Kimura-2-parameter model) generated five clades to represent distinct genera. Pangasius was further subdivided into two clades (Clade A: Pangasius bocourti-P. djambal and Clade B: P. nasutus-P. conchophilus). Given the marginal genetic divergence, indigenous and non-native species should be treated cautiously in allopatrically distributed species. The analysis used Automatic Barcode Gap Discovery (ABGD) and revealed barcode gaps between the intraspecific and interspecific distances. The sequences were partitioned into five groupings, corresponding with the species delineation based on the distribution of pairwise differences, which could not be differentiated using the NJ dendrogram. ABGD allows the recognition of one or two additional species using the recursive approach, but other taxonomic methods should be considered for a solid conclusion. DNA barcoding demonstrates the identification of closely related species, thus justifying its application towards the conservation of these fish.

Microalgae play an important function in aquatic environments by serving as the energy foundation of the food chain for all aquatic species. Microalgae produce a wide range of bioproducts, including polysaccharides, lipids, pigments, proteins, vitamins, bioactive chemicals, and antioxidants. In this study, a dataset of identification of three microalgae isolated from freshwater riverine areas at Glami Lemi River, Malaysia is presented. The identification data was acquired using molecular identification using the PCR method and morphological observation. The morphological observation of the microalgae isolates, GL01, GL02, and GL03, showed the closest features and characteristics with Chlorella sp., Ankinstrodesmus sp., and Tetradesmus (Scenedesmus) sp., respectively. The sequence similarity analysis of partial 18s rDNA gene using BLASTn identified the three microalgae species as Chlorella sorokiniana for isolate GL01, Ankistrodesmus fusiformis for isolate GL02, and Tetradesmus obliquus for isolate GL03. Both morphological observation and molecular identification were in agreement in the determination of the species. This is the first report on the three microalgae species isolated from this area.

Aims: This study aimed to assess the effects of using insect larvae meals, such as BSF and BW larvae, as alternative feeds to commercial pellets on the growth performance and survival of Oreochromis spp. at the nursery stage. Study Design: This study followed the randomized control treatment with three different diet. Place and Duration of Study: This study was carried out at the Fisheries Research Institute Glami Lemi (FRIGL) in Negeri Sembilan, Malaysia, within 35 days from July to August 2023. Methodology: A total of 360 red hybrid tilapia (Oreochromis spp.) fingerlings weighing 0.62 ± 0.06 g were randomly distributed into 12 rectangular aquarium tanks (250mm) at a stocking density of 30 fish per tank. They were fed with commercial pellets (CP), Black Soldier Fly (BSF) larvae, and Bloodworm (BW). The feed amount was calculated at 10% of the total body weight per tank, with feeding conducted three times daily. The experimental setup was performed in triplicate. For the analysis of growth performances and fish survival, sampling was conducted weekly. Results: BSF larvae meal had high lipid and protein content, measuring 35.35 ± 0.21% and 29.67 ± 0.98%, respectively. BW larvae meal also showed high lipid and protein content, with 28.23 ± 1.33% and 27.94 ± 0.52%, respectively. Fish fed with BSF and BW larvae exhibited significantly higher survival rates, 93.3 ± 3.3% and 86.7 ± 14.5%, respectively, compared to the control group. Meanwhile, the group fed with the commercial pellet showed the lowest survival rate, just 74.4 ± 12.6%. Fish fed with the BW larvae recorded the highest weight gain, 1.07 ± 0.16 g, followed by fish fed with BSF larvae, 0.66 ± 0.11 g, and then fish fed with commercial pellets, 0.41 ± 0.09 g. Conclusion: Both BSF and BW larvae exhibited significant growth response properties to tilapia fingerings compared to commercial pellets. The findings from this study are promising and should be further verified at the farm scale.