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En sammanställning av pilotprojektet med DNA-inventering av järv i Norrbottens län 2023/2024
Full text linkKnubbsäl och storskarv i ett skyddsområde för fisk i Bohuslän
Full text linkSom en åtgärd för att återetablera nedfiskade lokala bestånd av olika arter av torskfisk och plattfisk inrättades år 2010 ett skyddsområde för fisk i havsområdet innanför Orust och Tjörn (8-fjordarområdet). Eftersom fiskbestånden i området inte visat några tecken på återhämtning har andra påverkansfaktorer än fiske uppmärksammats som tänkbara förklaringar, bland annat predation från knubbsäl (Phoca vitulina) och storskarv (Phalacrocorax carbo). Kunskapen om förekomsten av säl och skarv i anslutning till skyddsområdet för fisk är emellertid bristfällig. Här presenteras resultat från olika inventeringar av knubbsäl och storskarv som utförts i området runt Orust och Tjörn, inklusive 8-fjordarområdets skyddsområde för fisk.Den nationella miljöövervakningen av knubbsäl i augusti och inventeringar av häckande storskarv i maj-juni visar att populationerna av knubbsäl och storskarv har ökat i storlek under 2000-talet såväl i Skagerrak som i området runt Orust och Tjörn. Inventeringsresultaten tyder även på att ökningen avstannat under senare år och att framför allt antalet knubbsälar nu ser ut att minska. Den nationella kustfågelinventeringen i maj-juni och den nationella vinterräkningen av sjöfågel i januari visar att förekomsten av både knubbsäl och storskarv är betydligt större i områdena utanför Orust-Tjörn och i närheten av skarvarnas kolonier än i skyddsområdet för fisk innanför Orust-Tjörn. Inventeringarna indikerar dock inga tydliga ökningar varken av knubbsäl eller skarv i området under 2000-talet. Den nationella kustfågelinventeringen och den nationella vinterräkningen av sjöfågel ger en bild av långtidsförändringar i förekomst av storskarv, men inventeringarnas geografiska täckning är begränsad, förutom i kustfågelinventeringen 2001–2013 och de år vinterräkningen gjorts med flygplan. Ett större antal årligt inventerade rutor eller sektorer i området runt Orust och Tjörn skulle ge ett bättre underlag. Genom att lägga till en hösträkning av sjöfågel skulle man även få bättre förståelse för hur antalet storskarvar varierar mellan områden och år under en period då antalet skarvar i området är som högst.Förekomsten av knubbsäl och storskarv i skyddsområdet för fisk varierade tydligt mellan olika årstider. Antalet sälar var som högst under vintern, men med stor variation mellan år beroende på isutbredningen, medan antalet skarvar var som högst under hösten. Det syntes inga tecken på att sälar och skarvar förekom i större tätheter i specifika vattenområden. De olika inventeringar som bedrivits i området runt Orust och Tjörn ger liknande resultat om förekomsten av storskarv i skyddsområdet. Den del av skyddsområdet som inventerats varje månad 2019-2021 uppskattades hysa upp till 200 skarvar vintertid och upp till 800 under hösten. Antalet knubbsälar var betydligt färre, oftast bara några tiotal
Mode I fracture energy release rates of European beech wood-adhesive bonds
Full text linkThis paper presents mode-I fracture energy release rates (G(I)) of European beech wood (Fagus sylvatica) adhesive bonds for three common types of adhesives pressed with two levels of pressure and glued with three spread rates. Flat double cantilever beam tests with a shear corrected compliance method were used to derive G(I). A high pressing pressure of 1.0 versus 0.1 MPa resulted in higher G(I)-values for phenol resorcinol formaldehyde and melamine urea formaldehyde adhesive systems (not significant), but did not affect the polyvinyl acetate system. A low adhesive spread rate of 50 g m(-2) clearly resulted in lower G(I)-values for all three systems, while no clear differences were found between spread rates of 100-200 g m(-2) for the formaldehyde systems. The herein presented G(I)-values of beech adhesive bonds can be used to further evaluate the suitability of beech in glued load-bearing timber structures and promote optimising beech wood-adhesive systems for high G(I)
Effects of the physical form of starter feed on the intake, performance, and health of female Holstein calves
Full text linkAvailable literature on the effect of various physical forms of starter feed (PFSF) on calf performance is conflicting. Thus, this study aimed to investigate the effect of the PFSF on feed intake, growth performance, blood metabolites, and the health of dairy calves. Twenty-four female Holstein calves (5-d-old; 40.4 +/- 3.86 kg BW; mean +/- SD) were used in a completely randomized block design. Calves were individually housed and randomly assigned to the treatments (n = 12 calves/treatment): (1) textured starter feed (TSF, a mix of pelleted ingredients and whole-kernel corn) and (2) pelleted starter feed (PSF). Both starter feeds had the same ingredients, nutrient compositions and pellet die size. Calves were fed the same milk replacer and weaned in a step-down scheme at 67 d. Health was evaluated daily until weaning. Treatments did not affect starter feed intake, water intake, BW, ADG, withers height, or clinical signs of disease (loss of appetite, ear position, and cough incidence). Nonetheless, scores for abnormal attitude (P = 0.01), ocular discharge (P 0.05). In conclusion, starter feeds containing whole-kernel corn as a texturizer did not improve the intake and performance of dairy calves compared with pelleted starter feed; however, improvements were observed in health scores and non-disease probability of calves fed textured starter feed. (c) 2024 Published by Elsevier B.V. on behalf of The animal Consortium. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
Greater biomass from Arctic greening absorbs increased grazing pressure from a large herbivore
Full text linkArctic warming is causing widespread "greening" of tundra ecosystems. What this means for plant-herbivore relations, including the grazing pressure herbivores exert on increasingly productive tundra ecosystems, is poorly understood. Svalbard is one of the fastest warming places on Earth, with concomitant increases in both forage biomass and reindeer numbers. In 11 years between 1998 and 2023, we measured grass biomass and the proportion of shoots grazed in mesic grass-dominated tundra to evaluate whether increased forage biomass of grass absorbed the grazing pressure of more reindeer. Also, we used GPS data from adult female reindeer (2009-2023) to identify if grazing pressure was relieved by spillover into other habitats. During the study period, reindeer abundance, estimated by annual capture-mark-recapture, tripled, while grass biomass only doubled. Grazing pressure increased from 4% to 8%, which was lower than expected from the increased reindeer density. This discrepancy was not caused by spillover into other habitats, but rather by increased grazing in higher-biomass patches that have emerged with summer warming. Our findings support the notion that increased summer forage has contributed to Svalbard reindeer population growth, notably by making available higher biomass grass swards that allow for greater food off take
Validation of the HemoCue Hb 801 portable haemoglobin analyser for fish blood
Full text linkHaemoglobin concentration ([Hb]) assessment in fish blood has become a routine parameter to measure the health and welfare status of the animals. The original method (haemoglobincyanide method, best known as the Drabkin method) for measuring Hb in human and animals is not well suited for work outside of a laboratory setting. It is relatively time consuming, contains hazardous cyanide elements, and requires specific laboratory material. As an alternative to the Drabkin method, portable analysers have been developed for human blood, but they need to be first validated for fish blood before being used in experiments. In this study, the performance of the new HemoCue Hb 801 portable haemoglobin analyser was compared to the validated Drabkin method to determine [Hb] in three fish species. Hb readings between the two methods were not different for any of the species tested (rainbow trout, Onchorynchus mykiss, Atlantic wolffish, Anarhichas lupus, and Nile tilapia, Oreochromis niloticus). Therefore, this new portable device can be readily used to measure Hb in fish blood. Unlike the previous model from HemoCue, the Hb 201+, this device does not need an incubation time or a correction factor, representing a major gain of time and precision
Governance networks for agroecology transitions in rural Europe
Full text linkGovernance networks, made of diversified and multidisciplinary actors, have a prominent role in the development and implementation of actions for agri-food system transformation that foster both farm-level and societal change, as in the case of agroecology transitions. This article aims at delivering a typology of governance networks, building on evidence from across Europe. By adopting a governance network theory perspective, a multiple case study is developed through participatory research, by characterising the emerging governance networks from transition actions at different levels in the pathway towards agroecological redesign. Three types of governance networks are identified. Adoption networks develop from early-stage actions in the agroecology transition pathway, to facilitate the shift from conventional to more sustainable farming practices. Positioning networks emerge from actions to create a demand for agroecologically produced food, through the development of marketing strategies and the creation of market channels. Amplification networks are the closest to agroecological redesign, originating from actions structured towards participatory planning and the development and reinforcement of diversity and transdisciplinarity. Advisory services play a key role in all three types, by fostering knowledge diffusion and exchange, as well as by developing trust among farmers and encouraging cooperation, including conflict management. The role of advisory services for agroecology could be strengthened further through targeted policy. Measures to sustain multi- actor cooperation have the potential to create these conditions by developing and exploiting synergies between and within value chains, and with other relevant actors, including consumers
The microbiome of a perennial cereal differs from annual winter wheat only in the root endosphere
Full text linkThe intensification of agriculture has led to environmental degradation, including the loss of biodiversity. This has prompted interest in perennial grain cropping systems to address and mitigate some of these negative impacts. In order to determine if perennial grain cultivation promotes a higher microbial diversity, we assessed the endophytic microbiota of a perennial grain crop (intermediate wheatgrass, Thinopyrum intermedium L.) in comparison to its annual counterpart, wheat (Triticum aestivum L.). The study covered three sampling sites in a pan-European gradient (Sweden, Belgium, and France), two plant genotypes, three plant compartments (roots, stems, and leaves), and two sampling time points. We observed that the host genotype effect was mainly evident in the belowground compartment, and only to a lesser extent in the aboveground tissues, with a similar pattern at all three sampling sites. Moreover, intermediate wheatgrass roots harbored a different bacterial community composition and higher diversity and richness compared to their annual counterparts. The root bacterial diversity was influenced by not only several soil chemical parameters, such as the carbon:nitrogen ratio, but also soil microbial parameters, such as soil respiration and dehydrogenase activity. Consistent findings across time and space suggest stable mechanisms in microbiota assembly associated with perennial grain cropping, underscoring their potential role in supporting biodiversity within sustainable agricultural systems
Intraspecific epigenomics divergence in brown bears (Ursus arctos): insights from genome-wide DNA methylation patterns
No full textEpigenetic mechanisms such as methylation can influence gene expression and play a crucial role in the adaptation to local environmental conditions, thereby introducing non-genetic variability within species. Here, using a Reduced Representation Bisulfite Sequencing approach (RRBS), we compared the methylation patterns in blood and muscle across three European brown bear populations. Our results clearly demonstrated that, beyond tissue-driven divergences, the methylation patterns of the three populations are significantly distinct. Differentially methylated sites, possibly associated with genomic features involved in development and anatomical differentiation, are widespread across the bear genome. This finding supports previous studies suggesting a role for the alteration of developmental pathways in shaping phenotypic novelties with potential adaptative significance. Our results underscore the importance and the effectiveness of including epigenetic approaches in studying wild non-model organisms. Investigating the epigenome can be especially relevant for endangered populations that have experienced a significant erosion of genomic diversity
