Search Results (94)

Ovarian interstitial tissue (IT) is a prominent but poorly characterised component of the koala ovary. This study analysed the morphology and immunohistochemical profile of IT in the koala ovary across different reproductive phases. Ovaries from ten sexually mature females were examined histologically and immunolabelled for aromatase, HSD3B2, HSD17B1, the follicle stimulating hormone receptor (FSHR), and the luteinizing hormone receptor (LHR). IT occurred as multifocal cortical aggregates composed of two distinct cell types. Large interstitial cells were polygonal with highly vacuolated and weakly eosinophilic cytoplasm and were morphologically consistent with a steroidogenic phenotype. Small interstitial cells were densely eosinophilic, non-vacuolated, and morphologically uniform across reproductive phases. Immunohistochemical analysis revealed that small interstitial cells exhibited the broadest expression of steroidogenic markers in the ovary, with coexpression of HSD3B2, HSD17B1, aromatase, FSHR, and LHR. In contrast, large interstitial cells exhibited comparatively limited enzyme and receptor expression. Staining intensity across all markers was strongest during the interoestrous phase, moderate in the proliferative phase, reduced in the luteal phase, and minimal or absent when the koalas were lactating, suggesting potential cyclical variation in IT function. Granulosa, theca and germinal epithelial cells showed variable expression of steroidogenic enzymes and gonadotropin receptors, indicating that ovarian steroidogenesis in the koala may be more heterogeneous than predicted by the classical two-cell, two-gonadotropin model. Together, these findings provide preliminary evidence for the steroidogenic capacity of ovarian IT in the koala, indicating that its activity varies across reproductive phases, and appear to suggest a unique cellular organisation compared to other mammals. As these results are based on morphology and immunohistochemistry alone, further functional studies are required to confirm the steroidogenic output and clarify the physiological significance of IT in this species. Full article

Co-infections are increasingly recognized as drivers of disease in ornamental fish, yet their genomic underpinnings and zoonotic implications remain underexplored compared to farmed species. Leveraging a One Health perspective, we investigated an acute mortality event in koi carp and characterized a co-infection by opportunistic aquatic bacteria that are also implicated in human disease. We isolated Aeromonas veronii and Shewanella sp. from a moribund koi using culture, biochemical assays, and MALDI-TOF MS, then generated draft genomes and performed orthology (OrthoVenn3), pathway annotation (KEGG BlastKOALA/Mapper), secondary-metabolite mining (antiSMASH), and virulence/resistome screening (VFDB/CARD), complemented by antimicrobial susceptibility testing. Clinically, affected fish showed dropsy/ascites, scale loss, abnormal buoyancy, and reduced activity. Phylogenomics positioned A. veronii Koi-2 within the A. veronii complex near species thresholds (ANI ~96.1%; dDDH ~70.2%), while Shewanella sp. Koi-1 formed a distinct lineage below accepted cut-offs relative to S. seohaensis (ANI ~95.9%; dDDH ~67.6%). The virulome comprised 194 loci in A. veronii Koi-2 and 152 in Shewanella sp. Koi-1 is enriched for adhesion, secretion, iron uptake, and immune-evasion functions. Genotype–phenotype agreement was high for multidrug resistance: Shewanella sp. encoded OXA-436 and rsmA, matching β-lactam resistance and reduced fluoroquinolone/phenicol susceptibility, whereas A. veronii carried tet(A), OXA-1157, cphA3, sul1, and aadA3 consistent with tetracycline, β-lactam, sulfonamide, and aminoglycoside resistance profiles. In conclusion, genome-resolved diagnostics confirmed a mixed Aeromonas–Shewanella co-infection with broad virulence potential and convergent resistance mechanisms, supporting the routine use of genomics to distinguish single- versus mixed-agent disease and to guide dual-coverage, mechanism-aware therapy in ornamental fish medicine while informing zoonotic risk mitigation. Full article

Koalas are an iconic Australian species now classified as nationally endangered due to habitat loss, predation, disease, and vehicle collisions. Yet, because of their nocturnal and arboreal nature, koala movement on the ground between trees remains poorly described. Ground visits are fraught with danger, with two-thirds of koala deaths occurring due to vehicle strikes and dog attacks. Quantifying these behaviours can provide insights for conservation efforts targeted to their time on the ground. To quantify detailed movement patterns, we collared nine koalas in a highly fragmented agricultural landscape with tri-axial accelerometers for 8.50 ± 1.17 days. Using an annotated dataset of observed behaviours, we trained Random Forest models to classify four main behavioural states: Motionless in Tree, Feeding & Grooming in Tree, Other Movement in Tree, and Walking. Koalas spent 57.5% ± 14.2% of their time moving in trees, 26.8% ± 13.5% motionless in trees, 15.6% ± 2.7% feeding and grooming, and only 0.2% ± 0.1% walking on the ground (around 3 min daily). Koalas walked most frequently between 2 am and 5 am. Our findings highlight a major discrepancy between mortality rates on the ground and frequency of ground time, indicating that focused mitigation during these infrequent events could yield disproportionately high conservation benefits. Full article

This study assessed the suitability of Woppa (Great Keppel Island), Queensland, as potential koala (Phascolarctos cinereus) habitat by combining existing koala-habitat ranking datasets with satellite-derived vegetation-health indices to inform conservation planning. This exploratory analysis establishes a spatial baseline to guide future ecological surveys, cultural consultation, and restoration planning on Woppa. Analysis of the Koala Habitat Ranking (NESP) and Regional Ecosystems (RE) layers indicated that only 2.7% of the island’s vegetation is classified as high-quality koala habitat. Satellite-derived indices (NDVI and LAI) were used to evaluate the vegetation condition of these and other vegetated areas across wet and dry seasons; some high-ranked patches displayed comparatively greater resilience to seasonal stress; however, the remote-sensing data did not confirm the presence or abundance of key Eucalyptus species. Given the small extent of high-ranked habitat and projected climate stressors, the study does not recommend translocation. Instead, it emphasises the need for targeted ground-truthing to verify tree species and habitat structure, monitoring of vegetation health, habitat restoration where feasible, and co-designed decision-making with the Woppaburra People, including assessments of carrying capacity, genetic viability, and disease risk, before any reintroduction is contemplated. Full article

Koalas (Phascolarctos cinereus) are threatened by habitat loss, fragmentation, and population isolation, increasing the risk of inbreeding and extinction. Genomic tools are valuable for guiding management decisions, and a standardised tool genomic is the most effective approach. In this study, an integrated genomic SNP assay was developed and validated as a comprehensive monitoring tool for koala conservation. The panel unifies SNP markers from previous approaches (DArTseq, exon-capture, whole-genome sequencing) into a standardised platform and incorporates novel fitness-related loci linked to immunity, thermoregulation, diet, and reproduction, alongside pathogen targets such as koala retrovirus (KoRV) and koala papillomavirus (KoAA). The assay was validated across key conservation applications, including population diversity and differentiation, parentage assignment, sex determination, provenance testing, and pathogen screening, using a variety of sample types (blood, tissue, swabs, scat), from previously tested populations across the distribution. A total of 3358 informative SNPs were identified, including 210 high-confidence outliers associated with immune and stress-response functions, indicating strong potential to capture adaptive variation. By integrating existing genomic resources with new adaptive and predominant pathogen loci, this cost-effective, standardised assay provides a unifying genomic framework for koala management, supporting applications from veterinary diagnostics to long-term monitoring under the National Koala Recovery Plan. Full article

The pathogenesis of koala retrovirus (KoRV) has been explored in various contexts, yet its role in tumorigenesis remains incompletely understood. Unlike acute transforming retroviruses, KoRV lacks a viral oncogene but may contribute to oncogenesis via indirect mechanisms. However, the relationship between KoRV and telomere length, as a potential indicator of telomerase activity, has not been examined. This study investigates the effect of KoRV infection on telomere length in 47 samples from Southern Australian koalas in a novel telomere length quantification method. Telomere lengths of 30 KoRV-negative samples were compared to those of 17 KoRV-positive samples using the Absolute Human Telomere Length Quantification qPCR kit (ScienCell Research Laboratories, California, USA). The telomere length in KoRV-infected WBCs was significantly longer than the uninfected ones (t = −2.059, p-value = 0.045). In line with this, telomere length correlated positively with proviral load (r = 0.421, p-value = 0.003), further linking viral burden to telomere elongation. Furthermore, the effect of age on telomere length differed by infection status (β = −5329.7, p-value = 0.0038); KoRV-positive individuals exhibited longer telomeres at a younger age but experienced more rapid telomere attrition over time compared to KoRV-negative individuals. These results suggest KoRV promotes telomerase elongation ability and modulates age-related telomere dynamics, potentially contributing to subsequent cellular immortality and oncogenesis. These pathways may overlap with other retroviruses, where telomerase dysregulation contributes to their oncogenic potential. This study provides new insights into KoRV pathogenesis and DNA quantification methodology, which could be valuable for future research by identifying predictive markers for tumour progression and potential therapeutic targets in affected koalas. Full article

Each year, hundreds of female koalas are presented to koala hospitals suffering from a range of morbidities, many of which require euthanasia for animal welfare reasons. These koalas represent a possible resource for genetic recovery by means of oocyte retrieval for genome banking or use in assisted reproductive technology. To examine the feasibility of koala oocyte recovery, this study conducted a preliminary survey of follicular activity and disease presence in fixed ovarian tissues from koala cadavers in South East Queensland. Ovarian activity and pathology were assessed by gross examination and histology. Bursal pathology was categorized into koalas with no, small (<10 mm diameter), moderate (10–20 mm diameter), or large (>20 mm diameter) sized bursae, whereas uterine pathology was diagnosed by an experienced reproductive pathologist. Antral follicles were observed in 94.4% of ovaries recovered from koalas with no bursal or uterine pathology (n = 18/44), 95.2% of the ovaries of koalas with bursal but no uterine pathology (n = 11/44), 100% of the ovaries of koalas showing only uterine pathology (n = 4/4) and 89.5% of ovaries from koalas with both bursal and uterine pathology (n = 11/44). Of the fixed ovarian tissue suitable for PCR Chlamydia detection (35/44), none were positive. As proof of concept, oocytes were also collected and evaluated from six koala cadavers within 2 h post-mortem. Although further studies are required to determine the quality and viability of the retrieved koala oocytes, our preliminary survey provides strong evidence that ovarian activity mostly continues unabated, irrespective of reproductive pathology, and that oocytes can be recovered successfully. Full article

There is a widespread belief that koala conservation measures should be focused on ending forestry operations in native forests and that plantations should be the alternative source for timber. While advocates for conservation continue to promote this strategic approach, they overlook the fact that hardwood plantations also provide important habitats. Ongoing operations in both natural and planted forests continue to threaten the viability of the koala species, and populations in one of the koala’s core habitats in northern New South Wales (NSW) continue to decline. To improve conservation outcomes for this species in the wild, the Great Koala National Park (GKNP) has been proposed. While the process of establishing this park continues, ongoing forestry operations exert continuous pressure on koalas and their habitat within the proposed area of the park. This paper investigates how community stakeholders are collaborating with scientists to identify areas of high koala habitat value within the hardwood eucalypt plantations inside the proposed GKNP that are currently excluded from conservation and will be subject to ongoing timber extraction. Investigations of Tuckers Nob State Forest, which is inside the proposal area, confirmed the presence of both koalas and original forest inside the plantations which were excluded from conservation by the state government. Original trees and remnants were identified using historical aerial photography, which were orthorectified and matched against current NSW government imagery (SIX Maps); composite mosaics of photographic sheets and closeups (Quantum GIS) were imported into Google Earth Pro. Koala drone surveys, habitat ground-truthing, and on-ground scat and koala surveys of 120 ha involving various community stakeholders were conducted in December 2024 and revealed 25 koalas records, necessitating the reclassification of this area from plantation to prime koala habitat. Here, as in many other plantations in NSW, the findings of this study indicate significant numbers of original trees that are part of highly diverse nutrient-rich sites attractive to koalas. This leads to the conclusion that the exclusion of specific areas of the proposed park from conservation to allow for ongoing logging is inconsistent with recognized koala protection strategies. Hence, koala protection strategies need to consider the integrity of the reserve system in its entirety, and the whole area of the GKNP should be accorded the requisite status of a World Heritage Site. Full article

Endogenous retroviruses (ERVs) are remnants of retroviral infections that have become stably integrated into host germline genomes. Far beyond passive genomic elements, ERVs actively shape host evolution through complex mechanisms involving genetic innovation, immune modulation, and species adaptation. This review provides a comprehensive synthesis of ERV biology, highlighting recent advances in their classification, amplification mechanisms, and epigenetic silencing. Particular emphasis is placed on the cross-talk between ERVs and exogenous retroviruses (XRVs), demonstrating how receptor competition, recombination, and immune evasion contribute to virus-host co-evolution. We explore ERVs as molecular markers for phylogenetic reconstruction, with case studies such as Koala retrovirus (KoRV) and HERV-K illustrating regional transmission dynamics and co-opted immune functions. Additionally, we discuss the functional domestication of ERVs into regulatory elements, non-coding RNAs, and envelope-derived fusion proteins that influence gene expression, antiviral defense, and placental development. Full article

Intensive energy consumption in the building sector remains one of the primary contributors to climate change and global warming. Within Renewable Energy Communities (RECs), improving energy management is essential for promoting sustainability and reducing environmental impact. Accurate forecasting of energy consumption at the community level is a key tool in this effort. Traditionally, engineering-based methods grounded in thermodynamic principles have been employed, offering high accuracy under controlled conditions. However, their reliance on exhaustive building-level data and high computational costs limits their scalability in dynamic REC settings. In contrast, Artificial Intelligence (AI)-driven methods provide flexible and scalable alternatives by learning patterns from historical consumption and environmental data. This study investigates three Machine Learning (ML) models, Decision Tree (DT), Random Forest (RF), and CatBoost, and one Deep Learning (DL) model, Convolutional Neural Network (CNN), to forecast community electricity consumption using real smart meter data and local meteorological variables. The study focuses on a REC in Loureiro, Portugal, consisting of 172 residential users from whom 16 months of 15 min interval electricity consumption data were collected. Temporal features (hour of the day, day of the week, month) were combined with lag-based usage patterns, including features representing energy consumption at the corresponding time in the previous hour and on the previous day, to enhance model accuracy by leveraging short-term dependencies and daily repetition in usage behavior. Models were evaluated using Mean Squared Error (MSE), Mean Absolute Percentage Error (MAPE), and the Coefficient of Determination $R^2$. Among all models, CatBoost achieved the best performance, with an MSE of 0.1262, MAPE of 4.77%, and an $R^2$ of 0.9018. These results highlight the potential of ensemble learning approaches for improving energy demand forecasting in RECs, supporting smarter energy management and contributing to energy and environmental performance. Full article

The koala (Phascolarctos cinereus) is recognised as threatened across two thirds of its distribution and identified as particularly susceptible to climate change. The aim of this study was to assess the spatio-temporal variation in microclimate across koala home ranges and determine any tendency for koalas to exploit this variability. Temperature data loggers were set out in a grid pattern across the study site on St Bees Island, Queensland. Resident koalas were collared with GPS units recording location at night or during the day. Our results revealed that temperature variation across the landscape was greatest on the hottest days (~10 °C). During the day, koalas were found in areas of the landscape that recorded lower daytime temperatures, and during the night, they were found in areas that recorded the highest daytime temperatures. We postulate that koalas avoided the hottest areas of their range during summer days and were more likely to use cooler non-fodder trees but utilised them at night because these areas corresponded with the location of fodder trees. From our results, we suggest that the microclimate of non-fodder trees both (a) explains their selection by koalas during the day and (b) highlights their importance to koala persistence, in addition to the known fodder species. Full article

Koalas (Phascolarctos cinereus) face many threats, with one of them being the disease chlamydiosis caused by the bacterium Chlamydia pecorum, a cause for infertility and one of the main causes of population decline. In New South Wales, Queensland, and the Australian Capital Territory, the koala is an endangered species, but in Victoria, koalas are widespread and overabundant in some areas. The koala populations in the You Yangs Regional Park (YYRP) and Brisbane Ranges National Park (BRNP) in Victoria are reported to be in decline, although there have been no studies looking into population density or disease. The aim of this study was to investigate the presence of C. pecorum in the koala populations of the YYRP and BRNP to understand whether disease may be a cause of concern. DNA was extracted from scats, and qPCR was used to detect the presence and load of C. pecorum. C. pecorum was found in 12/18 (66.7%) scat samples. Clinical signs of disease, age, and sex did not affect infection shedding load. These results confirm the presence of chlamydiosis within the YYRP and BRNP koala populations. More detailed studies are recommended to quantify prevalence of the disease in these populations and to understand the consequences of chlamydiosis in these areas. Full article

This study was developed to profile the oral microbiome of free-ranging Queensland koalas and its association with age, gingivitis and periodontitis. Using next-generation sequencing of 16S rRNA genes, the microbiota of oral plaque samples from eight koalas across different age groups (joey, juvenile, adult and old) were compared. The findings revealed significant shifts in microbiota composition with age and disease presence. At the phylum level, Proteobacteria were the most dominant phylum, especially in younger koalas. Proteobacteria abundance decreased with age, while Bacteroidetes, Fusobacteria and Actinobacteria increased. At the genus level, Acinetobacter declined with age. Fusobacterium and Porphyromonas became more prominent genera in older koalas and those with periodontal disease. The beneficial genus Lactobacillus was detected only in the joey, suggesting a potential loss of protective microbes with age. Alpha diversity analysis showed high variability within individuals based on age. Alpha diversity was remarkably lower in younger koalas and increased with periodontal disease. Beta diversity suggested distinct microbiota composition differences between younger (joey and juvenile) and older (adult and old) koalas, although statistical significance was limited by sample size. This is the first detailed characterization of the oral microbiome in Queensland’s free-ranging koalas and highlights its association with age and oral health status. Findings may contribute to better understanding of oral disease progression in koalas and support conservation and health management efforts. Full article

This study reports the effects of pH culture on multi-biofuel production (hydrogen, ethanol, and 2,3-butanediol) by Enterobacter cloacae K1ga, isolated from koala and adapted to grow in 100 g dm⁻³ glucose. Batch cultures were performed in 1 dm³ bioreactors, controlling the pH at 5.5, 6.5, 7.5, and 9.2. Furthermore, cultures without pH control (with an initial pH of 9.2) were used as reference cultures. Controlling pH at 9.2 was detrimental to E. cloacae K1ga as no growth or biofuel production was observed. In contrast, reference cultures reached a maximum 2,3-butanediol (BDO) production (BDOP) of 22.9 ± 2.1 g dm⁻³ and ethanol production (EP) of 9.9 ± 0.7 g dm⁻³ and the highest hydrogen production (HP) of 2013.1 ± 275.7 cm³ dm⁻³. Meanwhile, a pH of 7.5 increased the accumulation of ethanol, obtaining the highest EP (14.0 ± 0.05 g dm⁻³). On the contrary, a pH of 5.5 was unfavourable for the fermentative metabolism of E. cloacae K1ga, showing the lowest production rates for the three biofuels and also the lowest EP (8.05 ± 0.35 g dm⁻³). The results demonstrate that the natural progression of pH during the growth of E. cloacae K1ga is an advantageous strategy for multi-biofuel production, since no tight pH control system is required. Full article

Background/Objectives: Neonatal intubation is a complex procedure, often associated with low first-pass success rates and a high incidence of complications. Video laryngoscopes provide several advantages, including higher success rates, especially for novice clinicians, a magnified airway view that can be shared with supervisors, and the ability to record still or video images for debriefing and education. However, video laryngoscope devices vary, raising the possibility of differences in usability. Methods: The study used mixed methodology, including observations, semi-structured interviews, think-aloud techniques, high-fidelity simulations, function tests, and questionnaires to assess usability, defined by the clinician satisfaction, efficacy, and efficiency of six video laryngoscope devices; (1) C-MAC^® with Miller blade, (2) GlideScope^® Core^TM with Miller blade, (3) GlideScope^® Core^TM with hyperangle LoPro blade, (4) Koala^® Vision Ultra with Miller blade, (5) Koala^® Handheld with Miller blade, and (6) Parker Neonatal with Miller blade. Clinician satisfaction was determined by the System Usability Scale (SUS), National Aeronautics and Space Administration Task Load Index (NASA-TLX), and clinician preference. Device efficacy was determined by first-pass success, number of attempts, and overall success. Efficiency was assessed by time to successful intubation and function test completion rates. Results: Neonatal video laryngoscopes varied considerably in design, impacting usability. All devices were deemed suitable for neonatal intubation, with the Koala^® Handheld, C-MAC^®, and GlideScope^® Core ^TM Miller demonstrating the highest usability. Conclusions: This simulation-based study highlights substantial variability in neonatal video laryngoscope usability, indicating the need for further research into usability in the clinical setting. Full article