Thermosensitive and mucoadhesive Xanthan gum-based hydrogel for local release of anti-Candida peptide

ABSTRACT Whakaweku are bundles of bracken fern (Pteridium esculentum) traditionally placed in lakes and rivers by Māori to harvest kōura (freshwater crayfish, Paranephrops spp.) in Aotearoa, New Zealand. Previous studies show they are effective for monitoring populations of kōura and toitoi (small eleotrid fish, Gobiomorphus spp.). We wanted to determine whether whakaweku are also effective for monitoring benthic macroinvertebrate communities in streams. We placed whakaweku in a hard-bottomed and a soft-bottomed reach of a rural stream in the Waikato, and took standard ‘kick-net’ samples from the same locations. We retrieved whakaweku after two and four weeks submerged. Whakaweku gave comparable results to kick-net sampling for common macroinvertebrate metrics (MCI, SQMCI, total richness and EPT* richness). Macroinvertebrate community composition was significantly different between the two methods, but most taxa were common to both. Macroinvertebrate metrics did not change significantly between two-week and four-week colonisation periods. A wider study would show whether whakaweku can distinguish between sites over a gradient of human impact. We recommend whakaweku in Māori cultural and community stream monitoring as it is inexpensive, simple to use, captures many macroinvertebrate taxa used in biomonitoring, works in different stream types and can be used to monitor kōura, toitoi and macroinvertebrates simultaneously.

Exploring the mechanism of intestinal injury induced by Bisphenol S in freshwater crayfish (Procambarus clarkii): Molecular and biochemical approaches

The biology of extinct animals is usually reconstructed from external morphological characters and comparison with present-day analogues. Internal soft organs are very rarely preserved in fossils and require high-tech approaches for visualization. Here, we report the internal anatomy of a female and male of the ~ 162 Myr-old lobster Eryma ventrosum from the Jurassic La Voulte-sur-Rhône Konservat-Lagerstätte in France using X-ray synchrotron tomography. The Erymidae is an extinct, species-rich, widespread and ecologically important Mesozoic family of decapod crustaceans. Our investigation revealed the anatomy of the locomotory, respiratory, circulatory, excretory, digestive, nervous and sensory, and reproductive systems at a resolution resembling low-magnification histology. Particularly notable is the detailed preservation of the small brain and the fragile hepatopancreas, the main metabolic organ of decapods that decays rapidly post-mortem. The remarkable preservation shows that the internal anatomy of Eryma ventrosum is closer to that of Nephropidae (clawed lobsters) than Astacidae (freshwater crayfish), their closest living relatives based on skeletal morphology. The microanatomy of the gonads and hepatopancreas indicates that the two specimens investigated were a young, well-nourished female and male prior to sexual maturity. The analysis of the soft anatomy reveals remarkable conservatism over 160 Myr and offers new insights into feeding, reproduction, life history and lifestyle of an important component of the macrozoobenthos of Middle Jurassic seas.

Family Parvoviridae consists of small, non-enveloped viruses with linear, single-stranded DNA genomes of approximately 4-6 kilobases, subdivided into three subfamilies, Parvovirinae, Densovirinae, and Hamaparvovirinae, and unassigned genus Metalloincertoparvovirus. Parvoviruses of aquatic animals infect crustaceans, mollusks, and finfish. This review describes these parvoviruses, which are highly host-specific and associated with mass morbidity and mortality in both farmed and wild aquatic animals. They include Cherax quadricarinatus densovirus (CqDV) in freshwater crayfish in Queensland, Australia; sea star-associated densovirus (SSaDV) in sunflower sea star on the Northeastern Pacific Coast; Clinch densovirus 1 in freshwater mussels in the Clinch River, Virginia, and Tennessee, USA, in subfamily Densovirinae; hepatopancreatic parvovirus (HPV) and infectious hypodermal and hematopoietic necrosis virus (IHHNV) in farmed shrimp worldwide; Syngnathid ichthamaparvovirus 1 in gulf pipefish in the Gulf of Mexico and parts of South America; tilapia parvovirus (TiPV) in farmed tilapia in China, Thailand, and India, in the subfamily Hamaparvovirinae; and Penaeus monodon metallodensovirus (PmMDV) in Vietnamese P. monodon, in unassigned genus Metalloincertoparvovirus. Also included in the family Parvoviridae are novel parvoviruses detected in both diseased and healthy animals using metagenomic sequencing, such as zander parvovirus from zander in Hungary and salmon parvovirus from sockeye salmon smolts in British Columbia, Canada.

Simple SummaryProcambarus clarkii is an economic freshwater aquaculture species which is popular with consumers for its delicious flavor and high protein content. Salinization of freshwater ecosystems is an increasingly pressing global issue that poses a significant threat to aquaculture. Salinity is an important environmental factor directly affecting the metabolism, growth, reproduction, and physiological processes of aquatic animals. In this study, crayfish were subjected to acute low salt (6 ppt) and high salt (18 ppt) stress and investigated using transcriptome sequencing technology. The response of the crayfish to different salinity stresses, especially immunity, metabolism, ion transport, and osmoregulation, was analyzed to illustrate the resistance mechanism of crayfish facing salt stress. The results of this study are intended to deepen our understanding of the mechanisms by which freshwater organisms respond to salinity stress and provide useful references for the healthy culture of crayfish and the utilization of saline soils.Salinization of freshwater ecosystems is a pressing global issue. Changes in salinity can exert severe pressure on aquatic animals and jeopardize their survival. Procambarus clarkii is a valuable freshwater aquaculture species that exhibits some degree of salinity tolerance, making it an excellent research model for freshwater aquaculture species facing salinity stress. In the present study, crayfish were exposed to acute low salt (6 ppt) and high salt (18 ppt) conditions. The organisms were continuously monitored at 6, 24, and 72 h using RNA-Seq to investigate the mechanisms of salt stress resistance. Transcriptome analysis revealed that the crayfish responded to salinity stress with numerous differentially expressed genes, and most of different expression genes was observed in high salinity group for 24h. GO and KEGG enrichment analyses indicated that metabolic pathways were the primary response pathways in crayfish under salinity stress. This suggests that crayfish may use metabolic pathways to compensate for energy loss caused by osmotic stress. Furthermore, gene expression analysis revealed the differential expression of immune and antioxidant-related pathway genes under salinity stress, implying that salinity stress induces immune disorders in crayfish. More genes related to cell proliferation, differentiation, and apoptosis, such as the Foxo, Wnt, Hippo, and Notch signaling pathways, responded to high-salinity stress. This suggests that regulating the cellular replication cycle and accelerating apoptosis may be necessary for crayfish to cope with high-salinity stress. Additionally, we identified 36 solute carrier family (SLC) genes related to ion transport, depicting possible ion exchange mechanisms in crayfish under salinity stress. These findings aimed to establish a foundation for understanding crustacean responses to salinity stress and their osmoregulatory mechanisms.

Lysozymes are hydrolytic enzymes, and they are ubiquitous among all living organisms. They are mostly associated with antibacterial properties through their muramidase activity, while other properties such as iso-peptidase activity are also common. Invertebrate-type (i-type) lysozymes include the enzyme Destabilase, which is present in the salivary secretions of the medicinal leach Hirundo medicinalis. Destabilase has the ability to hydrolyse the ε-(γ-glutamyl)-lysine iso-peptide bonds formed by transglutaminase in fibrin of vertebrate blood, thereby destabilising blood clots.We have identified an i-type lysozyme from the hemocytes of the freshwater crayfish Pacifastacus leniusculus, which was found to be upregulated at the protein level in response to an injection of the β-1,3-glucan laminarin. Based on its sequence we predicted that this lysozyme would lack muramidase activity, and therefore we decided to determine its putative immune function. The P. leniusculus i-type lysozyme (Pl-ilys), is a protein with 159 amino acid residues, including a 29 residue signal peptide, with a predicted molecular weight of 16 kDa and a predicted pI of 5.6. It is expressed primarily in the hemocytes and to a lesser extent in the hematopoietic tissue. A recombinant mature Pl-ilys using an E. coli expression system was produced, and we could ascertain that this enzyme was deficient of muramidase activity. Moreover, no iso-peptidase activity could be detected against the substrate l-γ-glutamine-p-nitroanilide. Analysis of the conserved domains in Pl-ilys showed a putative destabilase domain, and thus we tested the clot dissolving activity of this enzyme. We could show that the purified P. leniusculus clotting protein which had been coagulated and clotted with transglutaminase was dissolved by the addition of Pl-ilys. Taken together our results indicate that Pl-ilys has a clot dissolving or destabilising activity in crustacean blood.

Conspicuous colours have fascinated biologists for centuries, leading to research on the evolution and functional significance of colour traits. In many cases, research suggests that conspicuous colours are adaptive and serve a function in sexual or aposematic signalling. In other cases, a lack of evidence for the adaptive value of conspicuous colours garners interest from biologists, such as when organisms that live underground and are rarely exposed to the surface are nevertheless colourful. Here, we use phylogenetic comparative methods to investigate colour evolution throughout freshwater crayfishes that vary in burrowing ability. Within the taxa we analysed, conspicuous colours have evolved independently over 50 times, and these colours are more common in semi-terrestrial crayfishes that construct extensive burrows. The intuitive but not evolutionarily justified assumption when presented with these results is to assume that these colours are adaptive. But contrary to this intuition, we discuss the hypothesis that colouration in crayfish is neutral. Supporting these ideas, the small population sizes and reduced gene flow within semi-terrestrial burrowing crayfishes may lead to the fixation of colour-phenotype mutations. Overall, our work brings into question the traditional view of animal colouration as a perfectly adapted phenotype.

Abstract Effective conservation of endangered species depends on knowledge of their distributions, but species detection can often be challenging. An example of this is provided by the Critically Endangered Margaret River burrowing crayfish (Engaewa pseudoreducta), which is highly cryptic. Due to the burrowing habit of this crayfish, detection of this species currently requires a great deal of effort, the results are often non‐conclusive, and, as it involves manual excavation of their burrows, the habitat of this and other species is destroyed in the detection process. In response to these challenges, this study developed and optimized a species‐specific probe‐based qPCR assay targeting the 16S gene region to detect the target species from environmental samples. Three test substrates—chimney pellets (soil expelled by a crayfish as it digs its burrow), burrow scrapes (soil lining the inside of a burrow), and burrow water (water that is filling the burrow space)—were tested from 11 crayfish burrows thought to have been constructed by the target species to see if eDNA could be detected. DNA from the target species was successfully amplified from both chimney pellets (6/11 samples) and burrow scrapes (3/11 samples); however, E. pseudoreducta was not detected in any water samples. As previously stated, sampling techniques to confirm the presence of this species have relied on burrow excavation (resulting in habitat destruction) and were often not definitive; therefore, replacing the traditional survey method with a noninvasive eDNA‐based technique could be of enormous benefit to the management and conservation of this (and similar) species.

Crayfish Cherax quadricarinatus is one of the fishery commodities that has business prospects not only as an ornamental fish commodity but also as a consumption commodity. Disease attacks caused by bacteria cannot be avoided, so one of the efforts made to increase the resistance of crayfish by giving kappa carrageenan is to increase the resistance of the crayfish. The purpose of this study was to determine the level of resistance of C. quadricarinatus to A. hydrophila bacterial infection by giving kappa carrageenan with different frequencies which is effective for increasing lobster survival after challenge tests with A. hydrophila bacteria. The study was conducted using a completely randomized design (RAL) with five treatments and three replications, namely control (without injection of kappa carrageenan), 1 time, 2 times, 4 times, and 6 times of injection kappa carrageenan. During maintenance, kappa carrageenan was given at a dose of 5 μg/g of oyster by dissolving 2.5 mg in 1 ml of Phosphate Buffer Saline (PBS) and then injected into lobster as much as 20μl/head. on day 30, challenged with A. hydrophila bacteria. The results showed that giving kappa-carrageenan 2, 4, and 6 times showed the same results (P>0.05) on the absolute growth of crayfish. The survival rate of crayfish given kappa-carrageenan showed that the frequency of giving 4 times showed the highest survival rate. Water quality during the study consisting of oxygen 6.25 mg/l, carbodioxide 3.68 mg/l, pH 6.8, ammonia 0.17 mg/l, and temperature 26.9 °C showed that it was still in the range that was feasible as a maintenance media

Purpose. Compiling a list of sources, which may be useful for learning about studies and issues related to river crayfish, their ecology and biology. Methodology. The holistic approach allowed getting acquainted with a broad range of literature on the study topic, while the selective approach allowed focusing on specific aspects or authors specializing in this field. Attention was focused on papers in scientific journals and collections, materials of temporary teams, as well as monographs devoted to the studies on the biology of river crayfish. Findings. A thematic list of the main works - materials of international scientific and practical conferences, articles from collections of scientific works, thematic scientific collections, journals as well as monographs and abstracts of dissertations on the biology of crustaceans and their cultivation in global crayfish aquaculture has been prepared. The cited works cover the time period from 2019 to 2024. The bibliography contains 166 publications, placed in alphabetical order and described in accordance with the requirements of the HAC, in accordance with DSTU 8302:2015 «Information and documentation. Bibliographic reference. General provisions and rules of drafting», taking into account the amendments (UKND code 01.140.40). Practical value. The list can be useful for law-making activities, maintenance of ecological security of Ukraine, for specialists, scientists, students interested in crustacean biology and crayfish farming. Key words: crayfish, management, cultivation, commercial harvest, feeding, biology of freshwater crayfish.

Lobster air tawar (C. quadricarinatus) salah satu komoditas yang hidup diperairan danau, rawa dan sungai. Saat ini lobster air tawar sangat diminati baik untuk konsumsi maupun estetik akuarium. Penelitian ini bertujuan untuk meningkatkan pertumbuhan dan kelangsungan hidup lobster air tawar dengan menggunakan metode perbedaan dosis glutamin pada pakan komersil. Rancangan penelitian yang dilakukan adalah Rancangan Acak Lengkap (RAL). yang terdiri dari 4 perlakuan 3 ulangan. Selama 35 hari masa pemeliharaan. Penelitian menunjukkan perbedaan antar setiap perlakuan secara nyata terhadap pertumbuhan bobot mutlak, panjang mutlak, persentase pertumbuhan berat, laju pertumbuhan harian, dan kelangsungan hidup lobster air tawar (C. quadricarinatus). Penggunaan glutamin pada pakan komersil ini menunjukkan bahwa hasil terbaik pada dosis glutamin untuk pertumbuhan lobster air tawar (C.quadricarinatus) terdapat pada perlakuan V2 dengan dosis 2% ml dan paling rendah pada perlakuan V0 kontrol. Penelitian ini merekomendasikan penggunaan glutamin dalam pakan komersil untuk meningkatkan pertumbuhan dan kelangsungan hidup lobster air tawar (C. quadricarinatus).

Water quality in land-based fish production can be controlled through either instantaneous water exchange or costly wastewater treatment followed by recirculation. Agricultural-aquaculture integration is an excellent alternative technique for reducing nutrient discharge levels, boosting profitability, and converting fish culture wastewater into valuable products. The current study employed a solar energy system to power two separate IMTA-aquaponics systems (Nutrient Film Technique, NFT, and Floating Raft Systems, FRS) for the cultivation of Nile tilapia, African catfish, thin-lipped grey mullet, freshwater crayfish, freshwater mussels, and a variety of vegetables. Tilapia and catfish were fed exclusively on diets under the IMTA system. All wastewater from tilapia and catfish ponds, both dissolved and solid, flows sequentially to ponds containing other cultivated species. The water then flows through the IMTA system's terminal point to the NFT and FRS systems before returning to the tilapia and catfish ponds, allowing complete control of the nutrient flow throughout this entire circular system. Two 147-day production cycles were concluded. The results from the second production cycle are reported. Total biomass gain for aquatic species in the IMTA system was 736.46 kg, compared to 145.49 kg in the tilapia and 271.01 kg in the catfish monoculture systems. The current IMTA system had a cumulative feed conversion ratio (FCR) of 0.90, while the FCRs for tilapia and catfish were 1.28 and 1.42, respectively. Nile tilapia and catfish consumed 571.90 kg of feed containing 25.70 kg of nitrogen (N) and 9.70 kg of phosphorus (P), reflecting, and gaining 11.41 and 3.93 kg of dietary N and P, representing 44.40 and 40.46% dietary N and P retention, respectively. In the IMTA system, the addition of mullet and prawn as detrivores aquatic animals improves dietary N and P utilization efficiency to 59.06 and 51.19%, respectively, while the addition of mussels as herbivore animals improves dietary N and P utilization efficiency to 65.61 and 54.67%, respectively. Finally, using FRS and NFT as hydroponic systems increased dietary N and P efficiency to 83.51% N and 96.82% P, respectively. This study shows that the IMTA-Aquaponic system, as a bio-integrated food production system, can convert the majority of fish-fed residues into valuable products suitable for desert, rural, and urban areas in impoverished and developing countries.

An old unknown: 40 years of crayfish plague monitoring in Switzerland, the water tower of Europe

Production of complementary food using locally available underutilized materials has become of necessity to overcome the economic effects on importation. This research examined the chemical composition, functional, microbial and sensory qualities of complementary food produced from Rizgah (Plectranthus esculentus), baobab fruit powder (Adansonia digitata), soybean (Glycine max) and crayfish(Cambarus Sp) flour blend. The raw materials used were purchased, processed into flour and mixed in varied proportions of Rizgah: baobab: soybean:cray fish flour(100:0:0:0; 85:10:5:0; 75:15:10:0;70:15:10:;60:20:15:5;55:20:15:10) to produce complementary foods and analyzed for chemical, microbial and sensory qualities. The ash, crude protein, crude fat and crude fibre increased from 9.34 to 16.77, 4.93 to 9.28, 9.48 to 11.50 and 1.57 to 3.53%, respectively, while the moisture and carbohydrates content decreased from 9.42 to 7.77 and 65.38 to 53.71%, respectively with reduction in the added Rizgah flour (100 to 55%). The bulk density decreased from 0.34 to 0.28g/cm3, while the swelling, oil absorption and water absorption capacity decreased from 85.25-66.10%, 25.50-17.50% and 57.50-45.50%, respectively. The vitamin C, vitamin B1 and vitamin B6 increased from 5.7 to 7.50(mg/100g), 0.64 to 3.00(mg/100g) and 0.58 to 1.75(mg/100g), respectively, with increase in the soybean, baobab powder and crayfish. The total coliform count, total heterotrophic bacterial count and total heterotrophic fungi count decreased from 2.8×10-2 to 1.5×10-2, 7.5×10-5 to 2.3×10-5 and 3.1×10-3 to 1.8×10-3, respectively, with decrease in the added Rizgah (100% to 55%). The mineral content of the sample increased from 0.29 to 0.90mg/100g for iron, 0.01 to 0.047mg/100g for sodium, 1.68 to 71.88mg/100g for calcium, 8.19 to 12.50mg/100g for magnesium and 0.96 to 2.75mg/100g for phosphorus with increase in the quantity of crayfish.The anti nutrient content of the sample varied from 5.90 to 5.81mg/100g for tannin, 5.46 to 13.60mg/100g for phytate, 7.81 to 10.91mg/100g for trypsin, 0.82 to 2.04mg/100g for oxalate. The relative increase observed for the anti nutrient content could be due to the added soybean flour. The average mean scores for aroma, colour, texture, taste, and overall acceptability of the complementary food samples varied from 3.50 to 3.60, 3.50 to 3.60, 3.50 to 3.40, 3.70 to 3.50 and 3.10 to 3.40 respectively, the relative increase in the average means score of sensory quality could be attributed to the added crayfish. This study has shown that relatively high quality and safe complementary food can be produced from Rizgah flour with addition of soybean, baobab and cray fish.

Aim: To evaluate the antibiogram profile of Vibrio cholerae [V. cholerae] strains isolated from Cross River State environment. Study Design: The cross-sectional study was a completely Randomized design because it is flexible and yields maximum degrees of freedom for any experimental errors. Place and Duration of Study: This was conducted in the Department of Microbiology University of Cross River State Calabar, Nigeria, between 2022 and 2024. Methodology: A total of 1,155 V. cholerae strains were isolated from water samples and sea foods from the North, Central and Southern geographical zones of CRS. This was done to have a complete picture of the spatial distribution of these MDR strains of the test bacterial strains. A total of 30 samples were assessed from three different locations in each geographical zone, for the presence of V. cholerae strains using conventional culture methods and isolates identified bio/serologically with commercial polyvalent and monovalent antisera. The Clinical and Laboratory Standards Institute (CLSI) protocols, were implored, for testing the susceptibility of the isolates to 10 commercially used antibiotics. Results: A total of 529±9.90 (45.8%) of the isolates showed resistance to Augmentin 30µg and 83±2.92 (7.17%) showed resistance to Gentamycin 10 µg. The overall percentage mean resistance by source, showed that the lowest resistance was from Cray fish (44.26±18.422%), and the highest was from Periwinkle (2.17±6.10%). It was also observed that the isolates from Ikom (CR Center) were the most resistant, with, 31.93±25.41%, followed by Calabar (CR South) with 24.54± 19.43% and Obanlikwu (CR North), the least with 9.07±18.80%. Statistically, significant differences were observed in the resistance pattern of the isolates from the different sources and locations, with significant values of .00 respectively (P=.05). Conclusion: There are great Chances that human infections, caused by these environmental V. cholerae strains can arise from contacts with these environmental sources. There is therefore, a need to carry out a surveillance on these MDR V. cholerae strains to help curb any eventual case of cholera outbreak of in the state.

The combination of the increasing demand of freshwater crayfish exports, the reduced population sizes due to overfishing, the crayfish plague epidemics and the habitat degradation, have led to unrecorded translocations of Pontastacus leptodactylus in Greek lakes. In the present study, the genetics of five narrow clawed crayfish (P. leptodactylus) populations were studied, namely three translocated populations inhabiting in Northern Greece, one native Greek population from Evros river and one potential progeny source population from Turkey. Nine microsatellite loci previously designed for the specific species were investigated, in order to assess the levels of genetic diversity and further to confirm the origin of these translocated populations some decades after the translocation events. Our results confirmed that the source population for the translocated Greek population is the Turkish lake Eğirdir. Further, despite the low values of the number of alleles, heterozygosity, and FST the populations were generally diverse, providing evidence for local adaptation. The low values of FIS for the translocated populations in combination with the high values of gene flow, possibly indicate the existence of re-introducing events. Apart from the translocated populations, high levels of genetic diversity and heterozygosity were observed in Evros population, suggesting it as a possible unit for future conservation purposes both as a donor population for reintroduction purposes as well as a unique gene pool protection source. To the best of our knowledge this is the first study dealing with the genetic composition of Greek P. leptodactylus populations from Nothern Greece, operating as a first step towards the development of proper management practices for restocking events and monitoring of translocated populations.

BackgroundBiodiversity in freshwater ecosystems is declining due to an increased anthropogenic footprint. Freshwater crayfish are keystone species in freshwater ecosystems and play a crucial role in shaping the structure and function of their habitats. The Idle Crayfish Austropotamobius bihariensis is a native European species with a narrow distribution range, endemic to the Apuseni Mountains (Romania). Although its area is small, the populations are anthropogenically fragmented. In this context, the assessment of its conservation status is timely.ResultsUsing a reduced representation sequencing approach, we identified 4875 genomic SNPs from individuals belonging to 13 populations across the species distribution range. Subsequent population genomic analyses highlighted low heterozygosity levels, low number of private alleles and small effective population size. Our structuring analyses revealed that the genomic similarity of the populations is conserved within the river basins.ConclusionGenomic SNPs represented excellent tools to gain insights into intraspecific genomic diversity and population structure of the Idle Crayfish. Our study highlighted that the analysed populations are at risk due to their limited genetic diversity, which makes them extremely vulnerable to environmental alterations. Thus, our results emphasize the need for conservation measures and can be used as a baseline to establish species management programs.

Freshwater lobster (Cherax quadricarinatus) is a type of lobster that has the potential for developed as a cultured organism. The problem that often occurs is the low number of freshwater lobster production due to the relatively long reproductive time. Vitamin E is a nutrient that plays a role in improving the spawning process in animals. This research aims to determine the effect of vitamin E to artificial feed at different doses on spawning. The test animals used were 16 female freshwater lobsters measuring 4 inches, aged 6 months, with an average weight of 30-55 grams. The research was conducted over 60 days using an experimental method with a completely randomized design (CRD) consisting of 4 treatments with 4 replications each. Treatment A was without vitamin E, Treatment B had 250 mg/kg of feed, Treatment C had 450 mg/kg of feed, and Treatment D had 650 mg/kg of feed The results showed that the levels of gonad maturity, fecundity, degree of fertilization, egg hatchability, and survival rate were not significantly different among treatments. However, Treatment C yielded the best results, with a gonad maturity level of 10.60%, fecundity of 281.53 eggs, a fertilization rate of 8.59%, a hatchability rate of 62.50%, and a survival rate of 100%. Data analysis was conducted using analysis of variance (ANOVA) at a 95% confidence level. The results indicate that the addition of vitamin E to feed at different doses does not significantly affect the spawning of freshwater lobsters.

Water quality parameters such as dissolved oxygen, pH, and mineral content are important factors for aquaculture. Predictive analytics can predict water conditions in aquaculture and significantly reduce the mortality probability of aquaculture products. This paper applied stream predictive analytics to the freshwater lobster farming dataset where its real-time data supplied by End Node Unit (ENU) which integrated with dissolved oxygen (DO), potential hydrogen (pH), electrical conductivity (EC), and total dissolved solids (TDS). The real-time data of ENU in Structured Query Language (SQL) is normally displayed for remote monitoring and the analytics will only be done after in different processing platform called batch analytics. Instead of batch, this paper demonstrates capability of stream analytics where the real-time data query from ENU streaming through Structured Query Language (SQL) right into R Studio and Autoregressive Integrated Moving Average (ARIMA) predictions executed on the query table simultaneously on the same processing platform. Previously, ARIMA, Neural Network Autoregressive (NNETAR), and Naïve Bayes, were run and evaluated in R Studio to identify the best algorithm for stream analytics. Prediction procedure in R studio start with importing real-time data stored in SQL database and stream into R Studio using command of “dbGetQuery(con,sql)”. These three models evaluated the performance of freshwater lobster water conditions, dissolved oxygen (DO), potential hydrogen (pH), electrical conductivity (EC), and total dissolved solids (TDS). The data was collected for six months, and 70% was used as training data and 30% as test data. Compared to NNETAR and Naïve Bayes, ARIMA fits the entire data set well for 7 days; the ARIMA model exhibited lower absolute errors for pH and electrical conductivity, with errors ranging from 0.04 to 1.7 across days, while the NNETAR model had generally lower errors for TDS, with errors ranging from 0.3 to 0.7; however, the Naïve Bayes model's performance varied, with the lowest error for DO on day (5) 0.15 but higher errors for other parameters and days, including the highest error for electrical conductivity on day (6) 6.2. In conclusion, the average absolute errors for DO, pH, EC, and TDS are 0.163, 0.064, 0.705, and 0.498, respectively. Our findings underscore the efficacy of ARIMA for comprehensive water quality via stream prediction while highlighting the nuanced strengths and weaknesses of each model in forecasting specific parameters. This study contributes to the aquaculture literature by providing a nuanced comparative analysis of predictive models tailored to freshwater lobster farming, emphasizing the imperative role of stream predictive modelling. It enables real-time monitoring of water quality parameters, ensuring prompt interventions to maintain optimal conditions, thereby minimizing risks, enhancing aquaculture productivity, and ultimately contributing to sustainable and efficient freshwater lobster farming practices.