Search Results (45)

Ambrosia beetle Platypus quercivorus is a vector of Japanese oak wilt. Only females possess 4−12 mycangial pits on the pronotum, which are essential for carrying symbiotic fungi and are thought to be a significant determinant of beetle fitness. However, the factors influencing the pit numbers remain poorly understood. To elucidate the effects of environmental conditions and parental traits on the pit number, we conducted a controlled breeding experiment. Collected P. quercivorus broods were categorized into three groups (large, middle and small) based on their average number of maternal mycangial pits. Excluding the middle groups, male−female pairs from the same group (large or small) were inoculated into Quercus crispula logs and incubated under four temperature regimes: 18, 22, 26, and 30 °C. We analyzed offspring pit number and body weight relative to temperature and parental traits. Both traits increased at lower temperatures likely because accelerated metabolism and developmental rates at higher temperatures, reduces the time and resources available for body growth and pit development. Notably, the traits exhibited distinct inheritance patterns: offspring pit number was significantly influenced by maternal pit number but not by the body weight of either parent. In contrast, offspring body weight was significantly correlated with maternal pit number, paternal body weight, and maternal body weight. Thus, we conclude that temperature plays a critical role in shaping these traits. Parental effects indicate that both mycangium pit number and body weight are heritable in P. quercivorus. However, their distinct inheritance patterns suggest a weak genetic association between the traits, implying that they may evolve largely independently. Full article

Understanding platypus health and disease is made challenging by the cryptic nature of this unique and iconic species. The retrospective medical record review methodology offers a valuable tool to better understand platypus health. A multi-institution review was performed, with 21 organisations and individuals contributing veterinary and pathology records spanning 34 years and 5 Australian states and territories. In total, records were reviewed from 278 wild platypuses and 40 zoo-housed platypuses, with a combined total of 383 presentations. Data from these were extracted and analysed, providing information on demography (age, sex), geographic location, season, reason for presentation, outcome of presentation, and clinical and pathological findings. For wild platypuses, key findings included that the juvenile age class was disproportionately represented in Queensland and New South Wales, and that the peak in juvenile presentations corresponded with weaning. For both wild and zoo-housed platypuses, novel reports of neoplasia were identified, and in wild platypuses, the first reports of neural angiostrongyliasis. For zoo-housed platypuses, an area identified for future research is the high prevalence of presentations for skin lesions. This study contributes to our understanding of platypus health and disease and should be used to guide further work to improve both conservation and welfare outcomes for one of the world’s most unique mammals. Full article

This study aimed to formulate probiotic beverages using underutilized tropical fruit pulp, such as those of sincuya (Annona purpurea Moc. & Sessé ex Dunal), urraco (Licania platypus (Hemsl.) Fritsch), matasano (Casimiroa edulis La Llave y Lex), and jaboticaba (Plinia cauliflora Mart. Kausel), with acceptable sensory characteristics. The evaluations of color, vitamins, minerals, °Brix, pH, and titratable acidity (TA) were performed on the fruit pulps. Subsequently, four beverages inoculated with a mixed culture (Streptococcus thermophilus and Lactobacillus delbrueckii subsp. Bulgaricus) were produced, and °Brix, pH, TA, sensory acceptability, and colony-forming units (CFUs) were measured after 9 h of fermentation. The sincuya pulp exhibited the highest beta-carotene (334.37 IU mg/100 g) and potassium (444.49 mg/100 g) content. The sincuya beverage was the best in terms of sensory characteristics such as color, aroma, flavor, and general acceptability, with scores of 78%, 71%, 70%, and 71%, respectively. The urraco, sincuya, and matasano beverages exhibited CFU counts of 10.9, 10.4, and 9.7 Log₁₀ CFU/mL, respectively. These results demonstrate that the fruits and formulated beverages have technological potential, functional and probiotic benefits, and sensory characteristics that are attractive to consumers. This innovative approach suggests an alternative for improving nutrition using local resources and agro-industrial byproducts. Full article

Stream-dwelling fishes face diverse hydrological pressures, making the broadly distributed Opsariichthys bidens an ideal model for analyzing adaptive evolution. To elucidate its adaptation to a high-dissolved-oxygen and high-flow-velocity stream environment, a high-quality genome with comprehensive annotation is essential. In this study, we present the first telomere-to-telomere (T2T) reference genome for O. bidens, constructed using PacBio HiFi, Oxford Nanopore Ultra-long, and Hi-C technologies. The assembled genome spans 841.96 Mb, comprising 38 chromosomes, each in a single contig (contig N50 = 22.42 Mb, 2.5-fold higher than the previous version), achieving a gap-free standard with 99.34% BUSCO completeness. Additionally, 38 centromeric sequences, 37 double-telomeric sequences, and 1 single-telomeric sequence were successfully identified, providing essential molecular markers. Phylogenetic analysis revealed a divergence time of 13.5 million years between O. bidens and its closely related species Z. platypus, with collinearity analysis confirming their high genomic conservation. Gene family analysis revealed 350 expanded families enriched in pathways associated with adaptation to high-dissolved-oxygen environments (e.g., antioxidant defense, oxidative phosphorylation, mitochondrial electron transport chain) and high-flow-velocity environments (e.g., exercise endurance, myocardial contraction, actin binding). Positive selection analysis further identified multiple pathways and key genes involved in mitochondrial optimization, oxygen utilization, and metabolic regulation. The T2T assembly greatly improves assembly continuity and enabling precise identification of centromeres and telomeres for O. bidens. These results provide a robust foundation for studying its adaptive evolution to stream environment. Full article

Entomopathogenic fungi are a group of fungi that infect and kill insects to obtain nutrients, thereby contributing to the natural regulation of insect populations. In recent years, they have been increasingly utilized as biological control agents, particularly in response to the rising prevalence of pesticide-resistant pests in agricultural systems. Representative examples include Beauveria bassiana and Metarhizium anisopliae, which are regarded as natural enemies of pests in agroecosystems. Since the first report of Korean oak wilt disease in 2004, the disease has continuously spread across the country and causes severe damage to deciduous oak species, especially Quercus mongolica. Although many efforts have been made to effectively control the disease, including chemical treatments, the control efficacy was shown to be low, and given the environmental side effects arising from the use of insecticides, there has been a demand for alternative control strategies. Integrated Pest Management in forests promotes ecological sustainability by reducing chemical pesticide use, conserving biodiversity, and enhancing long-term forest health. In this study, to mitigate issues with disease management strategies, assessments were made on three entomopathogenic fungi, B. bassiana, M. anisopliae, and Purpureocillium lilacinum, as potential biological control agents against oak wilt disease and its insect vector, Platypus koryoensis. In this regard, we investigated the insecticidal efficacy and LT₅₀ of each entomopathogenic fungus, and the results showed that all three entomopathogenic fungal strains exhibited fast insecticidal effects against the insect vector, P. koryoensis, with M. anisopliae showing the fastest action, recording a lethal time to 50% mortality (LT₅₀) of 58.7 h. The spores of M. anisopliae were found to be sensitive to high temperatures, while demonstrating a relatively high germination rate under UV exposure and strong initial germination ability at low temperatures. Full article

This study investigated the contribution that treated effluent from five sewage treatment plants (STPs) made to water and sediment quality in rivers within Sydney’s Warragamba Dam catchment. Warragamba Dam is the main water supply for Australia’s largest city, supplying 90% of water for >5 million people. The catchment rivers are important habitats for biodiversity. The study was prompted by an earlier investigation that discovered elevated perfluorooctane sulfonate PFOS in the liver of a platypus found in a river in the Warragamba catchment. At the site where the PFOS-contaminated platypus was collected, the river sediment had a maximum PFAS content of 8300 ng kg⁻¹. This study collected water upstream and downstream of five STPs and from STP discharges. River sediment samples were collected downstream of STPs for per- and poly-fluoroalkyl substances (PFAS). Water attributes included major ions, salinity, nitrogen, phosphorus, metals, and PFAS. Our study confirmed that STP effluent discharges contributed to river nutrient concentrations favourable to algae. The mean total nitrogen (TN) below STP outfalls was 2820 µg L⁻¹, exceeding catchment guideline (TN < 250 µg L⁻¹) by an order of magnitude. PFAS were detected in 65% of STP effluent samples and in 76.5% of river sediment samples. Full article

Climate change-induced heavy rainfall during summer months can further increase suspended solid loads in rivers, elevating turbidity. Such elevated turbidity can compromise fish gill tissue integrity and impair oxygen uptake, potentially leading to fatal impacts in aquatic ecosystems. Therefore, this study aims to examine fish migratory behaviors and physiological responses to varying turbidity levels through experimental trials to generate baseline data for assessing fish habitat suitability. The experimental design comprised two primary components: an investigation of turbidity avoidance behaviors and an analysis of habitat compatibility through extended exposure to turbid conditions. This study focused on dominant freshwater fish species native to South Korea, Zacco platypus, Pseudopungtungia nigra, and Zacco koreanus. Fish condition in response to turbidity was monitored over a 15-day period, during which locomotor activity and water quality parameters were recorded. In the control group tank with no turbidity, all species exhibited unrestricted swimming patterns without depth preference. However, in moderate and high turbidity treatments, all demonstrated preferential utilization of middle- and lower-depth strata. In addition, the highest number of fish mortality occurred in high-turbidity zones because of respiratory impediments from elevated suspended solid concentrations. These findings provide valuable insights into fish mobility and habitat utilization patterns in rivers experiencing sudden turbidity events, such as those associated with weir operations. Full article

The platypus (Ornithorhynchus anatinus), a unique monotreme, represents a pivotal point in mammalian evolution with its distinctive traits, such as electroreception and venom production. Despite its evolutionary significance, the viral diversity within platypuses remains poorly understood. This study employed next-generation sequencing to investigate the virome of the dead platypuses, uncovering a range of novel and divergent viruses. Among the identified viruses were four complete genomes of papillomaviruses (OaPV1–4) exhibiting substantial divergence from known strains, suggesting a novel genus within the subfamily Secondpapillomavirinae. Additionally, five novel parvoviruses were detected, including two with complete genomes, highlighting the complex viral ecosystem of the platypus. Phylogenetic analysis placed these viruses in unique evolutionary branches, further demonstrating the platypus’s evolutionary significance. A circular DNA virus, a tombus-like virus, and a nodamuvirus were also identified, expanding the understanding of viral diversity in monotremes. These findings offer crucial insights into viral evolution in one of the most unique mammalian lineages, emphasising the need for further exploration to assess ecological and pathological impacts on platypus populations. Full article

Spinacia oleracea L. cultivar platypus leaves are identified as a functional food due to their nutrient composition which promotes health beyond basic nutrition. Considering the increasing use of food supplements, S. oleracea baby leaves have been extracted by maceration, solid–liquid dynamic extraction (SLDE)-Naviglio, and ultrasound-assisted extraction (UAE) using EtOH and EtOH:H₂O mixtures. The analysis of the extracts by using LC-ESI/HRMSMS revealed 42 compounds (flavonoids, polar lipid derivatives, and 20-hydroxyecdysone), along with primary metabolites, detected by NMR analysis. A principal component analysis (PCA) of LC-ESI/HRMS and NMR data was performed, revealing how 20-hydroxyecdysone and flavonoids, the specialized metabolites mainly responsible for the biological activity of S. oleracea leaves, occurred in the highest amount in the EtOH and EtOH:H₂O (70:30, v/v) extracts obtained by SLDE-Naviglio extraction. 20-hydroxyecdysone was also quantified in all the extracts via LC-ESI/QTrap/MS/MS using the Multiple Reaction Monitoring (MRM) method. The EtOH extracts obtained by SLDE-Naviglio and maceration showed the highest content (82.16 and 81.27 mg/g extract, respectively). The total phenolic content (118.35–206.60 mg GAE/g), the flavonoid content (10.90–41.05 mg rutin/g), and the Trolox Equivalent Antioxidant Capacity (TEAC) (1.63–2.05 mM) of the extracts were determined. The EtOH:H₂O (70:30, v/v) extract analyzed by using SLDE-Naviglio showed the highest phenolic and flavonoid content and radical scavenging activity. Full article

The platypus (Ornithorhynchus anatinus) is an amphibious, egg-laying mammal of high conservation value that is found only in Australia. The zoonotic bacterium Leptospira interrogans serovar Hardjo was discovered in platypuses in prior studies, but little is known about its epidemiology. Samples in the Platypus Serum Bank were tested in 2023 and the results were combined with historical records. Antibodies against L. interrogans serovar Hardjo were found in 50% of 464 serum samples from 411 platypuses collected from 14 river basins in southeastern Australia between 1981 and 2012; prevalence remained high over three decades in the Shoalhaven River population. Seroprevalence increased with age, suggesting environmental exposure. Individual platypuses had persistent titres, some for six years. Seropositive females lactated, juveniles were recruited into the population, and there were no reports of clinical leptospirosis. Three necropsied platypuses were seropositive and had mild nephritis with leptospires in the renal tubules. The high seroprevalence, persistent titres, lack of disease, mild renal lesions, and renal colonisation suggest the platypus may be a maintenance host. Sympatric cattle had L. interrogans serovar Hardjo titres, but the spatial association with seropositive platypuses was statistically weak. Other mammalian wildlife species and sheep also have L. interrogans serovar Hardjo titres; therefore, a complex ecological network must be considered. A landscape-wide study is recommended to properly assess transmission pathways and confirm who is infecting whom. Full article

As rivers face growing environmental challenges due to climate change and the construction of artificial structures, it is essential that we improve river ecosystems to maintain their ecological functions and preserve the health of aquatic habitats. The aim of this study was to assess the aquatic ecosystem health of the lower reaches of the Tan River. We employed the Physical Habitat Simulation System and Hydrologic Engineering Center’s River Analysis System to calculate the ecological flow rate based on the weighted usable area (WUA) of Zacco platypus, which is a representative fish species in the Tan River, and the flow rate relationship curves. By analyzing the flow rates in the Tan River across different seasons from 2012 to 2021, we determined that the seasonal optimal ecological flow rate was 10.21–10.27 m³/s. Meanwhile, the WUAs for spring, summer, and autumn and winter were 90–100%, 95–100%, and 75–100%, respectively. Despite meeting the ecological flow criteria for summer, fall, and winter over 50% of the time, spring fell short at 41%; hence, the Tan River flow rates should be secured particularly in spring. This study highlights the urgency of addressing seasonal variations to ensure the overall health of the Tan River ecosystem. Full article

The pale chub Zacco platypus (Cypriniformes; Xenocyprididae; Jordan & Evermann, 1902) is widely distributed across freshwater ecosystems in East Asia and has been recognized as a potential model fish species for ecotoxicology and environmental monitoring. Here, a high-quality de novo genome assembly of Z. platypus was constructed through the integration of a combination of long-read Pacific Bioscience (PacBio) sequencing, short-read Illumina sequencing, and Hi-C sequencing technologies. Z. platypus has the smallest genome size compared to other species belonging to the order Cypriniformes. The assembled genome encompasses 41.45% repeat sequences. As shown in other fish, a positive correlation was observed between genome size and the composition of transposable elements (TE) in the genome. Among TEs, a relatively higher rate of DNA transposon was observed, which is a common pattern in the members of the order Cypriniformes. Functional annotation was processed using four representative databases, identifying a core set of 12,907 genes shared among them. Orthologous gene family analysis revealed that Z. platypus has experienced more gene family contraction rather than expansion compared to other Cypriniformes species. Among the uniquely expanded gene families in Z. platypus, detoxification and stress-related gene families were identified, suggesting that this species could represent a promising model for ecotoxicology and environmental monitoring. Taken together, the Z. platypus genome assembly will provide valuable data for omics-based health assessments in aquatic ecosystems, offering further insights into the environmental and ecological facets within this species. Full article

Gene expression patterns differ in different tissues, and the expression pattern of genes in the mammalian testis is known to be extremely variable in different species. To clarify how the testis transcriptomic pattern has evolved in particular species, we examined the evolution of the adult testis transcriptome in Theria using 10 species: two marsupials (opossum and Tasmanian devil), six eutherian (placental) mammals (human, chimpanzee, bonobo, gorilla, rhesus macaque, and mouse), and two outgroup species (platypus and chicken). We show that 22 testis-expressed genes are marsupial-specific, suggesting their acquisition in the stem lineage of marsupials after the divergence from eutherians. Despite the time length of the eutherian stem lineage being similar to that of the marsupial lineage, acquisition of testis-expressed genes was not found in the stem lineage of eutherians; rather, their expression patterns differed by species, suggesting rapid gene evolution in the eutherian ancestors. Fifteen testis-expressed genes are therian-specific, and for three of these genes, the evolutionary tempo is markedly faster in eutherians than in marsupials. Our phylogenetic analysis of Rho GTPase-activating protein 28 (ARHGAP28) suggests the adaptive evolution of this gene in the eutherians, probably together with the expression pattern differentiation. Full article

East Asia leads the global chemical industry, but environmental chemical risk in these countries is an emerging concern. Despite this, only a few native species that are representative of East Asian environments are listed as test species in international guidelines compared with those native to Europe and America. This review suggests that Zacco platypus, Misgurnus anguillicaudatus, Hydrilla verticillata, Neocaridina denticulata spp., and Scenedesmus obliquus, all resident to East Asia, are promising test species for ecotoxicity tests. The utility of these five species in environmental risk assessment (ERA) varies depending on their individual traits and the state of ecotoxicity research, indicating a need for different applications of each species according to ERA objectives. Furthermore, the traits of these five species can complement each other when assessing chemical effects under diverse exposure scenarios, suggesting they can form a versatile battery for ERA. This review also analyzes recent trends in ecotoxicity studies and proposes emerging research issues, such as the application of alternative test methods, comparative studies using model species, the identification of specific markers for test species, and performance of toxicity tests under environmentally relevant conditions. The information provided on the utility of the five species and alternative issues in toxicity tests could assist in selecting test species suited to study objectives for more effective ERA. Full article

Long-term ecological restoration can restore aquatic ecosystems to a certain extent and alleviate the crisis of freshwater fish biodiversity. In order to explore the fish community distribution patterns and key factors after ecological restoration and the health status of the watershed, fish and environmental data were collected from 39 sampling points in the Hun River Basin in the spring and autumn of 2021. A total of 51 fish species belonging to 11 families and 37 genera were collected during the survey, and the dominant species were Rhynchocypris lagowskii, Zacco platypus, Carassius auratus and Pseudorasbora parva. Compared with the results of past studies, the number of fish species has increased. The study found that the distribution of fish along the longitudinal gradient of the watershed showed obvious spatial differences and was divided into two groups. The results of canonical correspondence analysis (CCA) showed that agricultural land, urban land and grassland were the key factors for the spatial variation in fish communities in the Hun River Basin. The results of the F-IBI evaluation showed that the health status of the Hun River was fair or above fair, among which healthy, good, fair, poor and bad points accounted for 5.13%, 30.77%, 33.33%, 25.64% and 5.13%, respectively. The upper and middle reaches of the Hun River Basin were in better health, while the lower reaches were in poorer health, which was mainly affected by the intensity of human activities in different regions. This study will help watershed managers to make targeted restoration and protection measures for different regions. Full article