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Risk Factors for Dengue Virus Infection Among Hospitalized Patients in Bangladesh
No full textDengue virus infection (DVI), a mosquito-borne arboviral infection, is prevalent in tropical and subtropical regions, including Bangladesh, where incidence has surged over the past three decades—particularly in urban and peri-urban areas. This study investigates the factors influencing DVI seropositivity among clinically suspected patients admitted to the selected hospitals of Savar, Dhaka, and Chattogram. Data were collected from 850 clinically suspected patients admitted to two hospitals in Savar, Dhaka, and two in Chattogram during 2019. Questionnaire responses and laboratory test results (NS1, IgM, and IgG) were analyzed using descriptive statistics, chi-square tests, and logistic regression. Out of 450 admissions in Savar, 330 tested positive, while Chattogram reported 145 positives from 400 cases. No significant differences were observed between regions in relation to hospital type, season, gender, or household preventive measures. In Savar, DVI status was significantly associated with season, mosquito net use, and patient contact. In Chattogram, household repellent use and patient contact were key factors. Diagnostic tests varied in detection capability. These findings can inform targeted intervention strategies and public health messaging, such as promoting personal protection measures and community awareness campaigns, particularly in high-incidence urban settings. However, further research across diverse geographic and socio-ecological contexts is needed to enhance the generalizability and policy relevance of these results
The genetic architecture of temperature-induced partial fertility restoration in A1 cytoplasm in sorghum (Sorghum bicolor (L.) Moench)
No full textCytoplasmic male sterility (CMS) is used for commercial production of hybrid seed in sorghum. CMS-based hybrid breeding systems require female parental lines (CMS lines) to remain male sterile to prevent self-pollination and enable cross-pollination to generate hybrid seed. However, genetic and environmental factors can lead to the loss of male sterility in the pollen-accepting female parent, resulting in the production of contaminating non-hybrid seeds through self-fertilization with large economic consequences. It is known that high temperatures around flowering time induce sterility breakdown, or partial fertility; however, the genetic control of this phenomenon is poorly understood. To investigate the molecular processes controlling sterility breakdown, a large association mapping population of elite CMS parental lines was used to map the genomic regions controlling partial fertility. In this study, we used genome-wide association studies on a panel of 2049 sorghum lines grown in six field trials at Emerald Queensland representing six different environments. The seed planting was set up in such a way that flowering corresponded with the hottest part of the year. In total 43 significant SNPs were identified, indicating that the trait is controlled by multiple genes; however, previously identified major genes for fertility restoration were not the main cause of partial fertility. Diversity and linkage disequilibrium decay patterns in separate elite male and CMS pools also indicated the constraints on genetic diversity within the female parents due to partial fertility, rather than the frequency of the previously identified major fertility restoration genes. The understanding of the control of sterility breakdown provides new avenues for trait introgression in elite female pools
Analysis of the Microbiota of Milk from Holstein–Friesian Dairy Cows Fed a Microbial Supplement
No full textPrevious studies of direct-fed microbial (DFM) supplements showed variable effects on the microbiota and physiology of dairy cows. The main aims of this study were to investigate the milk microbiota of cows supplemented with a lactobacilli-based DFM compared to untreated cows; describe the changes; and quantify the association between the taxa and cow productivity. The study followed seventy-five Holstein–Friesian dairy cows supplemented with a DFM over 16 months compared to seventy-five non-supplemented cows. Twenty-five cows from each group were sampled for microbiota analysis. The top taxa significantly associated with the variables were as follows: Age (Mammaliicoccus_319276, Turicibacter), milk production (Turicibacter, Bifidobacterium_388775), DIM (Stenotrophomonas_A_615274, Pedobacter_887417), milk fat percentage (Pseudomonas_E_647464, Lactobacillus), calendar month (Jeotgalicoccus_A_310962, Planococcus), milk protein percentage (Tistrella, Pseudomonas_E_650325), experimental group (Enterococcus_B, Aeromonas), SCC (Paenochrobactrum, Pseudochrobactrum), and trimester of pregnancy (Dyadobacter_906144, VFJN01 (Acidimicrobiales)). These were identified using multivariable analysis. Twenty-six genera were associated with the differences between experimental groups, including Pseudomonas, Lactococcus and Staphylococcus. Microbial taxa that changed in relative abundance over time included Atopostipes, Brevibacterium and Succinivibrio. Many of these genera were also part of the core microbiota. Supplementation with the DFM significantly altered the milk microbiota composition in the dairy cows, highlighting the impact of long-term DFM supplementation on microbial communities
Macadamia planting density has a strong effect on orchard productivity in a decade-long trial
No full textAustralian macadamia (Macadamia integrifolia x M. tetraphylla) orchards are generally planted at low densities, taking ten years or more to reach maximum yield. Increasing planting density provided a substantial leap in the orchard productivity of temperate tree crops. Inspired by this transformation, the impact of planting density was evaluated in an experimental macadamia orchard, established in Central Queensland, Australia. Over ten years, three planting densities from high (5 x 2 m; 1,000 trees ha-1) to medium (6 x 3 m; 556 trees ha-1) and conventional low density (8 x 4 m; 313 trees/ha) were compared across two scion cultivars (‘HAES 741’, ‘HV A203’). High planting density increased early orchard productivity as expected, and ten years from planting, its cumulative yield per hectare was around 43% higher than that of the low planting density in both cultivars. This increase in early productivity is likely due to the greater canopy volume and light interception in the early life of the high-density system. However, the pruning requirements in the high-density system were relatively higher and had an adverse e ect on yield in this system. Thus, we foresee that maintaining high production beyond ten years will in part depend on appropriate canopy management. Concerns about an e ect of high planting density on nut quality are not justified, as our data shows no di erences between densities in regard to various nut quality parameters. Overall, increasing the planting density may be a valuable tool for improving macadamia orchard profitability. It will, however, require the development of a sustainable canopy management strategy to suit this intensified system
Long-Term Studies of Puccinia coronata f. sp. avenae in Australia Reveal High Pathogenic Diversity, Regional Virulence Differences, Evidence of Clonality and Rapid Emergence of Virulence Matching Deployed Host Resistance
No full textLong-term, detailed Australia-wide studies of pathogenic variability in Puccinia coronata f. sp. avenae (Pca) were conducted from 1 April 1998 to 31 March 2024, along with analysing crown rust resistance in oat cultivars grown to examine its potential role in shaping Pca populations. A total of 2846 identifications of 172 pathotypes were made from 1559 rust samples. Six regional populations (Queensland [Qld], northern NSW [nNSW], southern NSW [sNSW], Victoria and Tasmania [V&T], South Australia [SA], Western Australia [WA]) became more variable over time, and variability decreased along an east-to-west gradient. Evidence was obtained for migration of at least five pathotypes between eastern and western cereal belts, indicating limited gene flow between them predominantly in a west-to-east direction. Two pathotypes were isolated throughout the study in most eastern regions, providing evidence of long-term persistence of pathogen clones. Two major shifts in the composition of regional populations were documented. The first involved rapid adaptation by Pca to Avena sterilis-derived resistance genes following their deployment in principally grazing oat cultivars in the subtropical region spanning nNSW and Qld. The second shift involved large changes between regional populations in Qld, nNSW, sNSW and WA beginning around 2011, and in V&T and SA around 2015, which were associated with the emergence, spread and increase of pathotypes typified by virulence for Pc64. Because Pca spreads rapidly throughout Australia and moves freely between grazing, hay and milling oat crops, reducing the impact of this damaging disease will require the deployment of durable resistance in oats of all end-uses
Business planning for drought preparedness and resilience in the variable climate of Northern Australia
No full textNorthern Australia typically experiences an annual wet season (November to April) and dry season (May to October). However, it is common for wet seasons to fail, or be reduced, and dry periods to extend into drought. To survive the highly variable conditions that are predicted to increase with climate change, northern cattle producers are encouraged to implement management strategies for drought preparedness and resilience. Due to extensive land areas and high costs, most properties have limited fencing and water infrastructure which constrains best practice grazing land management.
The GrazingFutures Livestock Business Resilience project (GFLBR) is designed to enable a collaboration of livestock extension agencies to support Queensland cattle producers to analyse their business through the development of Farm Business Resilience Plans. Through the project, producers are supported to develop goals for their business and develop a plan to achieve these goals. Key business risks and challenges are also identified and strategies for risk reduction incorporated into the plan. A developed business plan also enables producers to apply for Queensland Government drought preparedness grants and low interest loans for improving capital infrastructure on their properties.
Kevin and Shelly Taylor on Ooralat Station, near Mt Surprise, Queensland, provide an outstanding case study of the benefits of using drought preparedness grants for improving capital infrastructure. The Taylor’s used the grants to fence 11 additional paddocks and improve water distribution. This work increased their ability to rest pastures over the wet season and thereby improve pasture composition and land condition. More water points for livestock have improved pasture utilisation across paddocks and property carrying capacity from 800 to 1,200 breeders. Irrigating pasture for hay production in one of the paddocks, has facilitated feed storage for managing future droughts.
The GrazingFutures Livestock Business Resilience project enables northern beef producers to be better prepared for climate variability, improve productivity and profitability, and landscape resilience
Innovation in Timber Processing—A Case Study on Low-Grade Resource Utilisation for High-Grade Timber Products
No full textNative forest timber supplies are declining, and industry needs to do more with less to meet growing demand for wood products. An Australian-based, vertically integrated timber manufacturing business is commissioning a spindleless lathe to produce engineered wood products from small logs. The literature on innovation in timber manufacturing was found to generally focus on technical innovation, with relatively little use of market-oriented concepts and theory. This was particularly true in the Australian context. Using a market-oriented case study approach, this research assessed innovation in the business. It aimed to inform industry-wide innovation approaches to meet market demand in the face of timber supply challenges. Interviews were conducted with key personnel at the firm. Data and outputs were produced to facilitate comparison to existing research and conceptual frameworks. The business was found to empower key staff and willingly access knowledge, information and data from outside its corporate domain. It was also found to prioritise corporate goals outside of traditional goals of profit and competitive advantage. This was shown to increase willingness to try new things at the mill and increase the chances that new approaches would succeed. Thinking outside of the corporate domain was shown to allow access to resources that the firm could not otherwise count on. It is recommended that wood processing businesses seek to emulate this element of the case study, and that academia and the broader sector examine further the potential benefits of using enterprise and market-oriented lenses to better utilise available resources and maintain progress towards corporate goals
Prevalence and Risk Factors of Coxiellosis at the Human–Animal–Environment Interface in the South Asian Countries: A Systematic Review and Meta-Analysis
No full textCoxiellosis, a zoonotic bacterial infection caused by Coxiella burnetii, affects diverse mammalian hosts and is prevalent worldwide, including in South Asia. This study aimed to investigate the epidemiology of Coxiellosis in South Asia, focusing on distribution, host diversity, prevalence, and associated risk factors at the human–animal–environment interface. Following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines and a registered protocol, online searches were conducted in Embase, PubMed, Scopus, and Web of Science on August 6, 2023, to retrieve articles from the South Asian countries without restrictions on hosts or timeframe. Two authors independently reviewed, extracted data, and assessed quality based on predefined criteria, which were then evaluated and compiled into a single document and analyzed. The review identified 112 articles published between 1954 and 2023. Among humans, the estimated pooled seroprevalence (EPSP) was 9.2%, and the estimated pooled carrier prevalence (EPCP) was 6.2%. Ruminant herd-level EPSP and EPCP were 77.3% and 74.6%, and at the individual level, were 11.9% and 5.3%, respectively. Seroprevalence was significantly influenced by country, tick infestation, reproductive disorders, age, and body condition of ruminants. Nonruminant mammals, such as dogs (16.8%), horses (6.0%), pigs (3.9%), and rodents (14.8%), were also seropositive. Several avian and reptile species showed EPSP rates of 14.5% and 29.2%, respectively. Bacterial DNA was detected in ticks and soil samples, with EPCP of 1.0% and 3.3%, respectively. We recommend prioritizing One Health surveillance and intervention to prevent infections among humans, livestock, poultry, pets, and wildlife. Special emphasis should be placed on aged and emaciated animals, tick infestations, and animals with reproductive disorders
Fish movement
No full textFish movements have long intrigued ecologists due to their complexity and far-reaching implications on survival, reproduction, and population dynamics. Advancements in tracking technologies, including emerging electronic and remote sensors and information derived from molecular, chemical, and isotopic markers naturally recorded in fish tissues, have propelled our understanding of where, when, and why individuals and populations move. Such tangible information on the direction, frequency, and timing of fish movements is key to supporting management, informing policy, and underpinning positive conservation outcomes. In this chapter, we aim to highlight the diversity of movement and migration strategies in fish, providing a blueprint of movement types at different spatial and temporal scales, as well as key methodologies and emerging approaches for studying fish movements. The goal is to broaden our understanding of how and why fish move, illustrated by representative and well-established case studies ranging from hourly or daily time steps, such as vertical migrations, to ontogenetic movements linking different life-history stages, all the way to transoceanic movements and diadromous migrations
Impacts of harmonic radar tagging on the flight ability of male and (Diptera, Tephritidae)
No full textUnderstanding the movement dynamics of fruit flies is critical to both surveillance and control strategies with much of what is known coming from mark–release–recapture or flight mill studies. However, recent studies have demonstrated the feasibility of field-tracking fruit flies using harmonic radar (HR). In this study, the effects of attaching HR tags to Bactrocera tryoni and Bactrocera jarvisi were assessed in large indoor cages with both cultured and wild flies. The Queensland fruit fly, B. tryoni, is a major horticultural pest in the Northern Territory and east coast of Australia. Jarvis' fruit fly, B. jarvisi, is one of the lesser Australian fruit fly species, with a distribution in northern and eastern Australia. Three flight-associated behavioural parameters were recorded: (1) flight success (proportion of flies that flew), (2) time to flight (period from release to take-off) and (3) flight duration (period from take-off to landing). Untagged flies were more likely to fly and also took flight more quickly than tagged flies with this result holding across fly species and fly origin (wild or cultured). Similarly, wild flies were more likely to fly than cultured flies, but no differences were observed between the flight successes of the two fruit fly species. For all tagged flies, mean time to flight increased with successive flight trials, while untagged flies mean time to flight over time varied with species and fly origin. The effect of tagging on flight duration varied by species (tagged > untagged for B. tryoni, tagged < untagged for B. jarvisi) but not by fly origin with species. Together, these results quantify the negative effects of HR tagging on B. tryoni and B. jarvisi flight behaviours that should be taken into account when interpreting the biological relevance of HR tracking studies. These results also suggest that HR tracking of fruit flies would benefit from the further development of smaller and lighter tags