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Effect of fasting and two different photoperiods on immune parameters in adult male and female house crickets (Acheta domesticus)
Get PDFInsects are often reared as a potential source of protein, both for human and animal consumption. However, food safety is a main concern and one common way of reducing the microbial load in insects is fasting them for 24-48 h. Fasting may pose a physiological stress with potential implications for welfare. Another parameter that can be manipulated in insect rearing facilities is the photoperiod, which affects maturation of the insects, and possibly immunity. In this study, adult Acheta domesticus of both sexes, reared in either 16 (16L:8D) or 12 h (12L:12D) of light, were fasted for 48 h or fed ad libitum prior to euthanasia. The immune parameters phenoloxidase (PO) activity, lysozyme concentration, haemocyte number and total protein content were investigated in haemolymph. The results revealed effects of both photoperiod and fasting on immunocompetence. Fasting lowered PO activity (p = 0.002) and haemocyte count (p = 0.005). The haemocyte count was especially affected by fasting in female crickets, and haemocyte count was correlated to protein concentration, and to PO activity in crickets reared in 16L:8D. A 16L:8D photoperiod lowered the protein content in haemolymph compared to 12L:12D (p = 0.045). Protein content has been correlated to disease resistance in previous studies, and was herein found to be correlated with PO activity. These results need to be replicated and investigated further to make recommendations for future cricket rearing, but the results point to the fact that rearing practices could have consequences for insect immunity
Comparative Proteomics of Resistant and Susceptible Strains of Frankliniella occidentalis to Abamectin
Get PDFWestern flower thrips, Frankliniella occidentalis (Thysanoptera: Thripidae) is an invasive agricultural pest with developed resistance to abamectin in some strains due to frequent treatment with the pesticide. In this study, we examined differentially expressed proteins (DEPs) between abamectin-resistant (AbaR; under abamectin selective pressure) and susceptible strains (AbaS; without abamectin selective pressure) of F. occidentalis. Proteins were isolated from second instar larvae of both strains and separated via two-dimensional polyacrylamide gel electrophoresis. Nano-flow liquid chromatography-tandem mass spectrometry identified selected protein spot features. From 70 DEPs, 43 spot features were identified: A total of 23 showed an increase in abundance, and 20 were down-regulated in response to abamectin pressure. The enzymatic and structural proteins were classified into the functional groups of macromolecular metabolisms, signaling and cellular processes, immune system, genetic information processing, and exoskeleton-related proteins. The up-regulation of exoskeleton-related proteins may contribute to forming a thicker cuticle, potentially hindering abamectin penetration, which is an interesting finding that needs further investigation. Two novel proteins, triacylglycerol lipase and cuticle protein CPF 2, were only expressed in AbaR. This work provides insights into abamectin resistance mechanisms in F. occidentalis, which will provide important information for developing insecticide resistance management approaches for this pest
Effective governance of marine recreational fisheries in Europe is needed to maximize the societal benefits of its fisheries
Get PDFMarine recreational fishing (MRF) is a socially and economically relevant fishing activity in Europe, but its impacts on ecosystems and the economy remain poorly understood, and management is limited. This paper evaluates the current European fisheries governance, particularly the Common Fishery Policy, in addressing MRF issues. Our evaluation highlights the lack of explicit recognition of MRF in European Union legislation, where recreational fisheries are not or insufficiently managed within a commercial fisheries-oriented policy framework. We recommend policy reform that explicitly recognizes recreational fisheries as a distinct fisheries sector with own interests, values and objectives, and dynamics that differ from those typical in commercial fisheries. On the operational level, we recommend involving key organizations representing MRF interests in advisory groups dealing with marine fisheries, nature conservation, and marine spatial use, and encourage sustainable fishing practices among all types of fisheries. To achieve this, there is a need for better and more comprehensive data collection, stakeholder engagement, and outreach to support effective MRF governance and management. By addressing these issues, Europe can maximize the benefits of MRF, while ensuring the sustainability of fisheries
What is a better chicken? Exploring trade-offs between animal welfare and greenhouse gas emissions in higher-welfare broiler systems
Get PDFDue to the animal welfare concerns in conventional methods of rearing broilers, chicken raised for meat, there is a push towards transition to higher welfare methods. However, this results in trade-offs as some aspects of higher welfare systems reduce production efficiency and thus increase greenhouse gas emissions. These trade-offs have however rarely been studied. This study aims to further the understanding by comparing the impact of reducing stocking density and switching to slower-growing broiler hybrids on broiler welfare and greenhouse gas emissions. Impacts on broiler welfare were determined by synthesizing quantitative welfare indicators from recent studies which assessed the welfare of broilers at different stocking densities and/or growth rates. The impact on greenhouse gas emissions from introducing these changes were modelled for chicken meat produced in Swedish broiler systems. Then, the magnitude of trade-offs associated with a reduced stocking density and/or use of slower-growing broilers were determined based on how these impacted broiler welfare and greenhouse gas emissions. The largest trade-offs were found when using slower-growing hybrids, since while this increased broiler welfare considerably, it also increased greenhouse gas emissions. The magnitude of the trade-offs was largely dependent on the growth rate of the slower-growing hybrid. Slower growth rates increased feed intake, and hence greenhouse gas emissions, but increased greenhouse gas emissions were partly offset by reduced emissions from parent animals. Trade-offs were smaller when reducing the stocking density in broiler houses, due to a moderate improvement of welfare but only a slight impact on greenhouse gas emissions. This study highlights the existing tensions between improving broiler welfare and minimizing greenhouse gas emissions and the need for tools to navigate these trade-offs. However, as greenhouse gas emissions from broiler production remain considerably lower than those of other livestock when higher welfare methods are used, we question whether minimizing greenhouse gas emissions should be a priority when conflicting with improving broiler and breeder welfare
Dynamic treatment units in forest planning improves economic performance over stand-based planning
Get PDFHigh-resolution, wall-to-wall forest information enables precision-driven decision-making in forest management planning. In a case study we compare planning approaches using such information for solving long-term forest planning problems. The two first approaches are based on dynamic treatment unit (DTU) planning with high-resolution cells (12.5 x 12.5 m2) or segments (0.27 ha on average), respectively, solved with a cellular automata heuristics. The third approach is a traditional stand-based approach using stands (5.2 ha on average) and linear programming to solve the planning problem. Fixed costs associated with cutting operations are quantified as each treatment unit is charged with an entry cost of 10 000 SEK. The entry costs are included in the DTU approach while in the stand approach entry costs are applied accordingly in a post-optimization routine. In large, the analyses are based on open-access tools and data provided by Swedish authorities. The traditional stand approach produced plans with 5.2-2.7% lower net present value compared to DTU planning. Most of the differences were caused by greater suboptimal losses in plans produced with the stand approach, but entry costs were also lower in DTU plans. While forestry was less profitable, treatment units were more spatially compact with stands, especially compared to cell-based plans. Therefore, we reason that a combination of modelling of direct costs and use of spatial proxy variables, such as common border length, may be advisable in DTU planning to achieve compact and realistic treatment units. Finally, the results indicate that high-resolution data and DTU planning may better utilize forests' potential of economic production, compared to the traditional stand approach
Distinct foliar fungal communities in Pinus contorta across native and introduced ranges: evidence for context dependency of pathogen release
Get PDFInter-continental study systems are crucial for testing ecological hypotheses, such as the widely cited Enemy Release Hypothesis (ERH), which seeks to explain the superior performance of plant species when they are introduced to new regions. Pinus contorta (lodgepole pine), native to North America, has been extensively introduced to Europe and the Southern Hemisphere, making it an ideal tree species for studying invasion hypotheses from a biogeographical perspective. We compared foliar fungal communities, especially pathogens, of P. contorta across two native-introduced region pairs (NIRPs): a northern NIRP (from Canada to Sweden) and a southern NIRP (from the USA to Patagonia), while also examining the differences between source plantations and invasion fronts within Patagonia. P. contorta underwent significant fungal community shifts and experienced pathogen release during its large-scale introduction from North America to Sweden and Patagonia. The fungal richness and relative abundance changes were more pronounced for the southern NIRP pair, where no closely related tree species to P. contorta are present in Patagonia. In Sweden, the presence of the phylogenetically related P. sylvestris and its associated local fungal community appears to play a role in influencing the foliar fungal communities associated with introduced P. contorta. In Patagonia, the incomplete co-invasion of fungal taxa from the USA emerges as a principal driver of the observed variability in fungal community composition and pathogen release following the introduction of P. contorta. In Patagonia, fungal community composition differences between source plantations and invasion fronts provided insufficient evidence that pathogen release occurs at this local scale. Integrating both biogeographical and phylogenetic perspectives, our study suggests that priority effects of local fungi appear to be a dominant community assembly process when introduction is done in a phylogenetically similar community; whereas, co-invasion of fungal communities is the dominant process in phylogenetically distant communities
Dynamic Outlier Slicing Allows Broader Exploration of Adaptive Divergence: A Comparison of Individual Genome and Pool-Seq Data Linked to Humic Adaptation in Perch
Get PDFHow genetic variation contributes to adaptation at different environments is a central focus in evolutionary biology. However, most free-living species still lack a comprehensive understanding of the primary molecular mechanisms of adaptation. Here, we characterised the targets of selection associated with drastically different aquatic environments-humic and clear water-in the common freshwater fish, Eurasian perch (Perca fluviatilis). By using whole-genome sequencing (WGS) on a large population dataset (n = 42 populations) and analysing 873,788 SNPs, our primary aim was to uncover novel and confirm known footprints of selection. We compared individual and pooled WGS, and developed a novel approach, termed dynamic outlier slicing, to assess how the choice of outlier-calling stringency influences functional and Gene Ontology (GO) enrichment. By integrating genome-environment association (GEA) analysis with allele frequency-based approaches, we estimated composite selection signals (CSS) and identified 2679 outlier SNPs distributed across 324 genomic regions, involving 468 genes. Dynamic outlier slicing identified robust enrichment signals in five annotation categories (upstream, downstream, synonymous, 5 ' UTR and 3 ' UTR) highlighting the crucial role of regulatory elements in adaptive evolution. Furthermore, GO analyses revealed strong enrichment of molecular functions associated with gated channel activity, transmembrane transporter activity and ion channel activity, emphasising the importance of osmoregulation and ion balance maintenance. Our findings demonstrate that despite substantial random drift and divergence, WGS of high number of population pools enabled the identification of strong selection signals associated with adaptation to both humic and clear water environments, providing robust evidence of widespread adaptation. We anticipate that the dynamic outlier slicing method we developed will enable a more thorough exploration of adaptive divergence across a diverse range of species
Passager för större däggdjur vid väg och järnväg
Get PDFDenna rapport redovisar studier av faunapassagers effektivitet för större däggdjur, med fokus på betydelsen av dimensioner (bredd, höjd, längd), markbeläggning och vegetation, skärmning mot trafikbuller, och mänskliga störningar såsom friluftsliv och lokaltrafik i passagen. Studierna genomfördes inom forskningsprogrammet TRIEKOL under åren 2017-2024, vid ett 40-tal passager utspridda över Sverige, anlagda specifikt för vilt eller för annat ändamål men väl anpassade till vilt. Vi valde de vilda klövdjuren som fokusarter: älg, rådjur, dovhjort, vildsvin och kronhjort (den sistnämnda kom slutligen inte att ingå i analyserna på grund av få observationer). Därtill ingick friströvande ren i viss mån i studierna. Den huvudsakliga metoden för datainsamling var med automatiska kameror (s.k. åtelkameror) monterade i och kring passagerna, för att samla in bilder på besökande djur dygnet runt och vid alla årstider. För varje besök noterade vi art, antal individer, riktning, tidpunkt och datum, i några fall ålder, kön och beteenden, samt inte minst om djuren passerade eller ej. Det senare låg till grund för att beräkna ett effektivitetsindex (andelen av besöken som resulterade i att djuren passerade). För planskilda passager (över- eller underpassager) pekade resultaten på att längden är den av dimensionerna som är av störst betydelse, alltså hur långt djuren behöver gå från ena sidan infrastrukturen till den andra, eller för underpassager hur långt de måste gå under brotaket. För de kortaste passagerna (20 m mellan vägsidor eller 7 m under tak) var effektiviteten 70%, men den minskade successivt till 30% för de längsta (>60 m mellan vägsidor eller 20-40 m under tak). Även bredden hade betydelse, men resultaten var motstridiga; högre effektivitet i bredare passager i några av analyserna men inget samband i andra. Möjligen går det att identifiera ett gränsvärde på ca 20 m bredd för älg, över vilket ytterligare bredd inte leder till bättre effektivitet. Höjden i underpassager verkade sakna betydelse för effektiviteten. De här resultaten pekar delvis i en annan riktning än tidigare forskning. En positiv tolkning av resultaten är att även relativt smala och låga passager kan ha en funktion för större däggdjur, och att andra faktorer är mer avgörande. Resultaten pekade vidare på att djuren föredrar jämna underlag och öppen mark i passagerna, och att de även kan passera via vattendrag och mindre vägar som går genom passagerna. Mänskliga störningar ledde till sämre effektivitet, särskilt sådana störningar som skedde i gryningen; djuren dröjde då upp till 30 timmar längre med att använda passagerna. Men tack vare långa perioder utan mänskliga störningar i de studerade passagerna fanns ändå möjligheter för djur att passera. Vissa resultat pekade på att effektiviteten ökade med avståndet till närmaste alternativa passagemöjlighet. Studier av betydelsen av skärmning mot trafiken är ännu pågående och inga resultat kan presenteras nu. Studierna av passager i plan med viltvarningssystem pekade på att dessa är nästan lika effektiva som planskilda passager när det gäller att få djur att passera, men där finns fortfarande en risk för viltolyckor planpassagerna eftersom djuren där måste passera över vägbanan. Vi diskuterar studiernas begränsningar, och föreslår alternativa och kompletterande analyser. Sådana analyser skulle även kunna omfatta fördjupade studier av redan insamlade data. Resultaten från studierna kan utgöra underlag i samband med uppdateringar av Trafikverkets styrande dokument för lokalisering och utformning av faunapassager
China Land Carbon Budget (CLCB1.0): a comprehensive estimate of the land carbon budget in China
Get PDFDeciphering consumer perceptions of Kisra prepared from biofortified and non-biofortified sorghum cultivars using the rate-all-that-apply (RATA) method
Get PDFIntroduction: Micronutrient deficiency remains a significant public health challenge in developing countries, including Sudan, particularly in rural areas, where access to a well-balanced diet is limited. This study evaluated consumer sensory acceptance and quality of Kisra, a traditional Sudanese fermented flatbread prepared from a combination of biofortified and non-biofortified sorghum cultivars.Methods: A panel of 100 assessors aged 18-75 evaluated nine Kisra products using hedonic overall liking and the rate-all-that-apply (RATA) technique.Results and discussion Kisra made from the biofortified Dahab cultivar received the highest overall liking scores (similar to 8, "like very much"), whereas blends such as Dahab + Dabar and Dahab + Arfa-gadamek showed moderate sensory acceptance (similar to 7). Hierarchical agglomerative analysis grouped the assessors into three clusters comprising 50%, 26%, and 24% of the panel. Among the demographic factors, education level had the most significant influence on overall liking (51%), followed by consumption frequency (25.5%), and age (23.5%). The RATA model demonstrated a high assessor repeatability (0.994), homogeneity (0.904), and low global error (9.617). Sensory attributes, namely porousness, thickness, and sourness, were key drivers of preferences for Kisra made from Dahab. These findings underscore the effectiveness of RATA in the product and scaling biofortified Kisra to combat malnutrition and cater to diverse consumer preferences