International Journal of Aquatic Biology
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Species confirmation of freshwater prawns in Ternate Island, Indonesia, through DNA barcoding: Not Macrobrachium rosenbergii
No full textFreshwater prawns of the genus Macrobrachium are widely distributed across tropical and subtropical regions. On Ternate Island, the local community refers to native freshwater prawns as “udang galah”, a name typically associated with Macrobrachium rosenbergii. This study aimed to accurately identify freshwater prawn species on Ternate Island using DNA barcoding. Prawn samples were collected from two different locations on Ternate Island: Togafo River, which has a steep gradient and flows directly into the sea without being affected by tidal salinity, and the river in Fitu Village, which consists of isolated pools with no connection to marine waters. Tissue samples were taken and preserved in 96% alcohol for molecular analysis. DNA barcoding results confirmed that the identified species is Macrobrachium lar, with genetic similarity ranging from 99.50% to 99.83% to reference data in GenBank. The presence of M. lar in isolated freshwater habitats raises questions about its dispersal patterns and life cycle, as this species is amphidromous and typically requires brackish water for larval development. These findings suggest the possibility of local adaptation or alternative dispersal mechanisms that warrant further investigation. Additionally, this study highlights the effectiveness of DNA barcoding for species identification, particularly for Macrobrachium species with high morphological variation or classified as cryptic
Effect of Hyssopus officinalis extract dietary supplementation on serological parameters, growth indices, and survival of common carp (Cyprinus carpio) against Aeromonas hydrophila
No full textThe hyssop (Hyssopus officinalis) is known as a medicinal plant with antimicrobial and antioxidant properties. Despite a long history of medicinal use of H. officinalis, very few studies have been reported on the effect of H. officinalis on fish. Thus, the present study tried to investigate the effects of H. officinalis extract as a food supplement on serological parameters, growth indices, and survival of common carp (Cyprinus carpio) against Aeromonas hydrophila. For this purpose, the fish were divided into four treatments and fed with concentrations of 0, 250, 500, and 750 mg/kg H. officinalis extract in the diet for 60 days. The results revealed that the growth indices, including weight gain, length gain, specific growth rate (SGR), and food conversion ratio (FCR) in the treatments supplemented with H. officinalis extract, have no significant difference compared to the control treatment. Serological analysis showed that total protein increased in the treatments supplemented with H. officinalis extract, which was signi?cantly different in 500 and 750 mg/kg H. officinalis extract compared to the other treatments. Immunoglobulin signi?cantly increased in 750 mg/kg H. officinalis extract compared to the other treatments. There was no significant difference in the amounts of albumin, glucose, cortisol, cholesterol, triglyceride, creatinine, urea, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), lipase, and amylase of all treatments (P>0.05). Total antioxidant capacity (TAC) significantly increased in the treatment containing H. officinalis extract. Serum malondialdehyde (MDA) decreased in the treatments supplemented with H. officinalis extract. The lowest MDA was observed in 750 mg/kg H. officinalis extract, which was significantly different from other treatments. Relative survival percentage (RSP) against A. hydrophila increased in the treatments fed with H. officinalis extract. The highest RSP was observed in 750 mg/kg H. officinalis extract treatment. It can be concluded that dietary H. officinalis extract had a proper effect on immune system stimulation, antioxidant capacity, and resistance against A. hydrophila in the studied fish
Antibacterial activity of green-synthesized gold nanoparticles produced by Spirulina platensis algae
Full text linkGold nanoparticles (AuNPs) synthesized using green methods are of paramount importance due to their potential in combating antimicrobial resistance and enhancing antioxidant therapies. Incorporating Spirulina platensis into nanoparticle synthesis offers a sustainable and eco-friendly alternative that addresses key challenges in modern nanomedicine. This research aimed to evaluate the efficacy of S. platensis as a bio-reductant for AuNP synthesis and to assess the resulting nanoparticles' biological activities. The purpose was to establish a reproducible, green synthesis protocol for high-quality AuNPs with improved biomedical potential. Spirulina platensis samples were procured in powdered form from a reputable supplier, ensuring consistency and purity for the subsequent extraction and synthesis processes. UV-Visible spectroscopy, XRD, and FE-SEM were used for characterization, while GC-MS analysis indicated bioactive reducing agents in the extract. AuNP production was confirmed by a significant surface plasmon resonance peak at 405?nm in the UV-Visible examination. XRD patterns showed a face-centered cubic structure with a prominent peak at 38° (2?). The FE-SEM scans showed that the AuNPs were mostly spherical, with an average diameter of 20-30 nm. Antibacterial assays showed inhibition zones of up to 20 mm against Acinetobacter baumannii and 18 mm against Enterococcus faecalis, with activity being dose-dependent, while antioxidant assays recorded a maximum scavenging inhibition of 73.8% at a concentration of 1?mg/ml. GC-MS analysis identified key bioactive compounds, including fatty acids, which make up approximately 30% of the extract, facilitating effective nanoparticle synthesis. Overall, the study confirms that S. platensis is an effective bio-reductant for the green synthesis of gold nanoparticles, which exhibit significant potential for various biomedical applications
Pathogenic Vibrios associated with loose shell syndrome in mangrove crabs (Scylla spp.)
Full text linkAn emerging disease known as loose shell syndrome, with unknown etiology, impacts mangrove crab aquaculture in the Philippines. This study investigated the presence and characterized pathogenic Vibrio spp., which might be implicated in loose shell syndrome in mangrove crabs, Scylla spp. Five bacterial isolates associated with loose shell syndrome in mangrove crabs were obtained and purified. Polymerase chain reaction (PCR) amplification using Vibrio-specific primers identified one isolate carrying the hemolysin (vhh) virulence gene of Vibrio harveyi, which was later confirmed by sequencing of the 16S rRNA. The other non-Vibrio isolates were Proteus, Shewanella, and Stutzerimonas. This study provides valuable insights into the possible etiology of loose shell syndrome in mangrove crabs, contributing to a better understanding of whether the condition stems from bacterial, environmental, or a combination of both factors
Production, remediation, health management, and economic returns of pond-based multi-trophic aquaculture giant tiger shrimp (Penaeus monodon) in varying feeding rates
Full text linkAn analysis and understanding of the proof of concept of Integrated Multi-Trophic Aquaculture (IMTA) technology, with varying feeding rates, in the context of disease and environmental management for better production of pond-based semi-intensive Penaeus monodon aquaculture, is evaluated in this study. The grow-out culture experiment was conducted for four months (120 days), utilizing eighteen units of 250 m2 ponds to hold the experimental trials. Six treatment combinations in triplicate were employed, comprising P. monodon as the main cultured species, with Chanos chanos and Oreochromis niloticus as the co-cultured species. The nutrient extractive species consisted of macroalgae Ulva fasciata and Gracilaria verrucosa, and mussel Perna viridis, at 2.5 and 5% feeding rates. The growth and survival of shrimp and finfish showed no significant difference among all treatments. Water quality levels among the treatments remained within optimal ranges. Shrimp reared within the shrimp-tilapia system and subjected to a 5% feeding rate manifested infection with White Spot Syndrome Virus (WSSV). Net revenue between the two feeding rates was consistently better (129.72-167.69 USD) at 2.5% feeding rates across all treatments. Overall, the shrimp-tilapia and IMTA systems demonstrated superior management and production performances compared to the shrimp polyculture system in terms of shrimp and fish production, plankton diversity, nutrient levels, and disease management. A 2.5% feeding rate is deemed appropriate for a shrimp-milkfish-Gracilaria-green mussel IMTA system
Growth performance and nutrient utilization of glass catfish (Kryptopterus lais) larvae in response to varying dietary protein levels
Full text linkThis study evaluated the effects of varying dietary protein levels (35, 40, 45, and 50%) on growth, feed utilization, and body composition in Glass catfish, Kryptopterus lais, larvae over 30 days. Larvae with an initial average weight of 0.15±0.01 g were distributed into 12 aquaria at a density of 50 individuals per tank. Fish were fed four times daily to apparent satiation. The results indicated that weight gain (WG) increased with dietary protein levels up to 40%, beyond which WG declined. Similarly, the feed conversion ratio was lowest in fish fed the 40% protein diet. The protein efficiency ratio was significantly higher in K. lais larvae fed the 40% protein diet compared to those fed diets containing 45 and 50% protein. Body composition analysis revealed that larvae fed the 40% protein diet exhibited the highest protein content, while those fed the 35% protein diet had a significantly elevated lipid content. Broken-line regression analysis, based on the specific growth rate, estimated the optimal dietary protein requirement for maximal growth performance to be 42.89%. These findings provide a quantitative basis for formulating diets that effectively meet the protein requirements of K. lais larvae
Study of mTOR/PTEN gene expression in gastric cancer cell line treated with ethanolic extract of Tetraselmis suecia microalgae
Full text linkThe second leading cause of death worldwide is cancer, and the fourth most prevalent cancer is stomach cancer. Natural seafood products include a variety of biologically active compounds with medicinal properties that may be useful in cancer therapy. This study aimed to assess the growth-inhibitory impact of the ethanolic extract of Tetraselmis suecica algae on the expression of mTOR/PTEN genes using the MTT assay in the cell line. The optimal IC50 dosage of this extract was 1000 and 750 ?g/mL at 48 and 72 hours, respectively. Tetraselmis suecica extract dramatically lowered the survival rate of gastric cancer cells, increased the apoptotic PTEN gene expression, and decreased the mTOR gene expression in the cell line. The extract of T. suecica, as shown in the current study, is potentially useful in the treatment of stomach cancer
Carrying capacity of 4 ppt saline water on the production performance and water quality profile of Nile tilapia (Oreochromis niloticus) at different densities
Full text linkIncreased density in fish farming can reduce the space for fish movement. The increase in density should be followed by considering the carrying capacity, which includes using an iso-osmotic environment, in this case, 4 ppt salinity. The purpose of this study is to analyze the use of 4 ppt salinity at different densities on production performance, water quality, physiological responses, and cost analysis in Nile tilapia. The experimental method was performed using Nile tilapia measuring 4.53±0.04 cm and an average weight of 1.45±0.03 g in each different density treatment, namely the control treatment of 1000 fish m-3, A 1250 fish m-3, B 1500 fish m-3, and C 1750 fish m-3, given a salinity 4 ppt with research parameters, including production performance parameters, water quality, and stress response. The results showed that the use of 4 ppt salinity in Nile tilapia can support the success of treatment C with a density of 1750 fish m-3, with water quality that is still in the optimal range for Nile tilapia and a survival rate of 95.6% with an average length of 6.6 cm, so that treatment C has the highest profit of IDR 51,500.00
Ecological study of microscopic protozoa in Abbasiya Canal, Iraq
No full textMicroscopic protozoa are water-based organisms. They pose significant concerns for human health, as serious diseases have been linked globally. This study aimed to identify and document the microscopic protozoa taxa of the Abbaseya watercourse and record some abiotic factors of their habitats and the watercourse's pollution level. Three sites along the Abbaseya watercourse were selected for collecting microscopic protozoa using a net with 55 ?m mesh openings. The abiotic factors assessed included total dissolved solids (TDS), electrical conductivity (EC), water flow, turbidity, pH, chloride ion concentration, and magnesium ion concentration. In total, 23 protozoan species of the classes Ciliata and Sarcodina were recorded. The diversity indices used were Jaccard’s similarity index and the Shannon-Weiner index. The highest Jaccard’s similarity index value, 0.79, was observed between April and May. The protozoan taxa identified in the Abbaseya watercourse are classified primarily into two classes: Ciliata and Sarcodina, with Ciliata having significantly higher taxa. A thorough assessment of protozoan species is vital for evaluating water quality, as it offers valuable insights into the ecological health of aquatic environments
Preliminary investigation on the tail regeneration of the juvenile marine polychaete, Perinereis wilsoni
No full textIn Perinereis wilsoni, gonad formation is thought to depend on germ cells supplied by the tail-end segment (pygidium). In this study, we investigated the regenerative capacity of germ cells in the pygidium following posterior amputation, using vasa as a putative germ cell marker. At 3 days post-amputation (dpa), pw-vasa-positive cells were scattered around the amputated area of the posterior segment, with some located near germ cell clusters in the distal parapodial region of the adjacent unamputated segment. By 4 dpa, pw-vasa expression was observed in the segment addition zone. At 7 dpa, pw-vasa was detected in germ cell clusters within the regenerating pygidium, and by 10 dpa, expression was evident in both the pygidium and the distal parapodia of the regenerated segment. These findings suggest that the re-emergence of germ cells in the pygidium may be supported by germ cell supply from the parapodia of the neighboring unamputated segment