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1.
Beyer  Nicole  Kirsch  Felix  Gabriel  Doreen  Westphal  Catrin 《Landscape Ecology》2021,36(9):2657-2671
Landscape Ecology - Pollinator declines and functional homogenization of farmland insect communities have been reported. Mass-flowering crops (MFC) can support pollinators by providing floral...  相似文献   
2.
The investigations were carried out with 484 sows from two farms (farm A: housing the sows in small groups of 8 animals each, farm B with a large group of 100 sows) and a total number of 982 inseminations. The number of agonistic interactions was registered for each sow during 48 h after mixing soon after weaning the piglets at farm A. The individual rank place in the social hierarchy was calculated on the basis of wins and defeats and the sows were divided in high and low ranking sows. At farm B the rank position was estimated on the basis of the daily feeding order at two electronic feeding stations (first half of the sows in the feeding order = high ranking, second half = low ranking). Additionally, the following parameters were recorded for each sow: parity, genotype, farrowing rate and litter size (total and alive born piglets). The analysis showed that sows with a high rank position had a significantly higher farrowing rate (88.8%) compared to group-mates with low rank places (82.8%, p = 0.051) (farm A). Sows with a high rank position reached a significantly higher litter size of total born piglets (12.66, 16.14 piglets per litter respectively) than the low-ranking group-mates (12.13, 14.83 piglets/litter respectively — farms A and B). When mixing sows, the time and the conditions (e.g. group size, space allowance per sow) have to be considered to prevent the negative influence of low rank order on fertility.  相似文献   
3.
Transition into higher education requires students to adjust to a new environment while showing greater independence in managing their own academic and personal life. This is often more difficult for international students who have to adjust to a different country, culture, and potentially another language. A cohort of first-year veterinary medicine students (17% international students) was investigated at a UK university using qualitative and quantitative questionnaires rating first-year experience and support services and statistical analysis of students' assessment performance. While the overall undergraduate perception was that they had learned a lot and progressed well, students in both groups struggled to cope with the workload. The non-UK educated students and students with English as a foreign language also struggled more with teaching delivery in lectures and participation in self-directed group learning and were more likely to feel that the veterinary degree program was too difficult. There was no statistical difference in how British and international students perceived the support system, although it was noticeable that the level of tutorial support was perceived as tutor-dependent. The international students particularly struggled with the assessments in early modules and also with the spot assessment method. However, in the practical assessments, using observed, structured practical exam stations, international and British students performed equally well. Increased support in the initial transition time, especially with regard to communication skills and confidence required for interactive teaching and learning environments such as small-group teaching, as well as increased time for specific assessment types, might benefit the needs of many international students.  相似文献   
4.
Landscape Ecology - Insect herbivores comprise the majority of macroinvertebrate communities of temperate grasslands and act as drivers for important ecosystem functions. Landscape- and local-level...  相似文献   
5.
The inhibition or delay of starch digestion by dietary compounds could help manage postprandial blood glucose levels. The objective of this study was to identify constituents from whole grain blue wheat capable of decreasing α‐amylase‐catalyzed starch digestion. An activity‐guided fractionation approach based on liquid chromatography was used to identify solvent‐ and alkaline‐extractable blue wheat constituents reducing α‐amylase‐mediated starch digestion in vitro. Fatty acids, potentially released from cell wall polymers by alkaline hydrolysis, inhibited the digestion of amylose, probably through the formation of amylose‐lipid complexes. However, the degradation of amylopectin was not affected by fatty acids. In addition, 1‐(3,5‐dihydroxyphenyl)heneicosan‐2‐one, a 5‐(2′‐oxoalkyl)resorcinol, was found to reduce starch digestion. However, because the digestion of both amylopectin and amylose was reduced, the inhibition mechanism was different from that of fatty acids. Further research is needed to evaluate whether this component also reduces starch digestion in vivo. Other phenolic compounds of blue wheat such as anthocyanins or hydroxycinnamates were not identified as major starch digestion inhibitors by using the activity‐guided fractionation approach.  相似文献   
6.
Current biodiversity conservation policies have so far had limited success because they are mainly targeted to the scale of individual fields with little concern on different responses of organism groups at larger spatial scales. We investigated the relative impacts of multi-scale factors, including local land use intensity, landscape context and region, on functional groups of beetles (Coleoptera). In 2008, beetles were suction-sampled from 95 managed grasslands in three regions, ranging from Southern to Northern Germany. The results showed that region was the most important factor affecting the abundance of herbivores and the abundance and species composition of predators and decomposers. Herbivores were not affected by landscape context and land use intensity. The species composition of the predator communities changed with land use intensity, but only in interaction with landscape context. Interestingly, decomposer abundance was negatively related to land use intensity in low-diversity landscapes, whereas in high-diversity landscapes the relation was positive, possibly due to enhanced spillover effects in complex landscapes. We conclude that (i) management at multiple scales, from local sites to landscapes and regions, is essential for managing biodiversity, (ii) beetle predators and decomposers are more affected than herbivores, supporting the hypothesis that higher trophic levels are more sensitive to environmental change, and (iii) sustaining biological control and decomposition services in managed grassland needs a diverse landscape, while effects of local land use intensity may depend on landscape context.  相似文献   
7.
Catrin Borberg  Steffen Hoy   《Livestock Science》2009,125(2-3):314-317
A total number of 26 groups of 8 sows each were mixed after weaning the piglets in a special stimulation pen, including 13 groups with and 13 groups without boar presence. Behavioural measurements were taken for 48 h after mixing and all agonistic interactions (AI) were recorded into a winner–loser-matrix. Additionally, the duration of the AI and the start situation (aggressor–receiver) were determined. Also the skin lesions of each sow 24 h before and after mixing were scored. A total of 90% of the AI were initiated by the dominant sow in the concerned dyad. In more than 50% of all cases low ranking sows were attacked by higher ranking sows. Low ranking sows had a significantly higher skin lesion score than high ranking sows (9.6 vs 6.9). 12.8% of the AI were fights. Fights (mean duration: 30 s) took ten times longer than attacks. Boar presence did not affect the total number of AI per sow but decreased the number of fights to almost half (3.6 vs 6.4). Duration of fighting was shortened by boar presence (14.9 vs 39.6 s). The skin lesion score and the sociometric parameters were unaffected by treatment. Frequency of AI per group was affected by the microclimate and the number of acquainted dyads (pairs). The number of AI was reduced by a higher enthalpy and a higher number of acquainted sows, respectively.  相似文献   
8.
Research is often an essential component of completing a veterinary medicine degree, with universities worldwide aiming to teach students a variety of techniques and general research comprehension and skills. As universities worldwide navigated the COVID-19 pandemic, it was often necessary to move towards distance learning, this was employed for the research module at The University of Nottingham, School of Veterinary Medicine and Science. Following completion of their independent research project, each student cohort was sent a student evaluation of the module questionnaire and quantitative and qualitative analysis was undertaken. In addition, assessment outcomes based on dissertation grade, supervisor grade and overall module score were analysed quantitatively. This was conducted on both the individual cohorts and between the pre- and peri-pandemic groups, ranging from 2017–2018 through to 2021–2022 cohorts. The students received increased dissertation and supervisor grades (by nearly 6%) during the 2021–2022 peri-pandemic cohort, when compared to the pre-pandemic cohorts, but did differ significantly compared to the 2020–2021 cohort. The pre- and peri-pandemic Likert-scale ratings for module organisation and assessment criteria were similar, workload management and the ability to explore concepts and ideas was reduced in the peri-pandemic cohorts, whereas the accessibility to resources was increased in the peri-pandemic students compared to those taught prior to the pandemic. Student feedback can provide essential information when designing and managing research projects and when compared to assessment grades it can help us understand attainment, essential information when providing a quality university level education whilst supporting student welfare following the COVID-19 pandemic.  相似文献   
9.

Context

Abundance and diversity of bumblebees have been declining over the past decades. To successfully conserve bumblebee populations, we need to understand how landscape characteristics affect the quantity and quality of floral resources collected by colonies and subsequently colony performance.

Objectives

We therefore investigated how amount and composition of pollen collected by buff-tailed bumblebee Bombus terrestris colonies was affected by the surrounding landscape (i.e. the proportion of forest, urban, semi-natural habitats) and how they were related to colony growth.

Methods

Thirty B. terrestris colonies were placed at grassland sites differing in surrounding landscape. Colonies were established in spring when availability of flowering plants was highest, and their weight gain was monitored for 1 month. We additionally recorded the quantity and compared plant taxonomic composition and nutritional quality (i.e. amino acid composition) of pollen stored.

Results

Bumblebee colonies varied little in the pollen spectra collected despite differences in surrounding landscape composition. They collected on average 80 % of pollen from woody plants, with 34 % belonging to the genus Acer. Early colony growth positively correlated with total amount of woody pollen and protein collected and decreased with increasing proportions of semi-natural habitats and total amino acid concentrations.

Conclusions

Our results suggest that woody plant species represent highly important pollen sources for the generalist forager B. terrestris early in the season. We further show that colony growth of B. terrestris is predominantly affected by the quantity, not quality, of forage, indicating that several abundant plant species flowering throughout the bumblebees’ foraging season may cover the colonies’ nutritional needs.
  相似文献   
10.
Antioxidant activity-guided fractionation based on three in vitro antioxidant assays (Folin-Ciocalteu, TEAC, and leucomethylene blue assays) was used to identify major antioxidants in blue wheat (UC66049 Triticum aestivum L.). After consecutive extractions with solvents of various polarities and multiple chromatographic fractionations, several potent antioxidants were identified by NMR spectroscopy and mass spectrometry. Anthocyanins (delphinidin-3-glucoside, delphinidin-3-rutinoside, cyanidin-3-glucoside, and cyanidin-3-rutinoside), tryptophan, and a novel phenolic trisaccharide (β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl-(1→6)-(4-hydroxy-3-methoxyphenyl)-β-D-glucopyranoside) were the most active water-extractable constituents. However, anthocyanins were found to be major contributors to the overall blue wheat antioxidant activity only when the extraction steps were performed under acidic conditions. Alkylresorcinols were among the most active antioxidants extractable with 80% ethanol in the TEAC assay. However, this may be due to a color change instead of a bleaching of the ABTS radical. Ferulic acid was found to be the major antioxidant in alkaline cell-wall hydrolysates. The contents of the most active antioxidants were determined.  相似文献   
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