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The provision of straw to pigs kept in conventional pens with concrete floor improves animal welfare, but the effects of straw on pigs’ performance are unclear. In two steps, we investigated the relationship between amount of straw provided to pigs and measures of performance in a set-up maintaining constant space allowance and controlled room temperature. From approximately 30- to 85-kg BW, pigs were housed in groups of 18 in pens (5.48 m × 2.48 m) with concrete floor (1/3 solid, 1/3 drained and 1/3 slatted). The pens were cleaned manually twice a week, and the designated amount of fresh uncut wheat straw was provided daily onto the solid part of the floor. In the first step, 48 pens were assigned to 10-, 500- or 1000-g straw per pig per day, while in the second step, 90 pens were assigned to 10-, 80-, 150-, 220-, 290-, 360-, 430- or 500-g straw per pig per day. Pigs were weighed at the start of the experimental period at approximately 30 kg and again at approximately 85-kg BW. The average daily gain increased 8.1 g (SEM 17) for every extra 100-g straw added daily (P < 0.001) resulting in 40 g higher average daily gain with 500 compared to 10-g straw per pig per day. The feed conversion ratio was not affected by the amount of straw provided, as the feed intake tended to be higher with increasing amounts of straw. Thus, between 10 and 500 g, the more straw provided, the higher the daily weight gain. As the nutritional value of straw is considered minimal, this result is likely due to improved gut health from the increasing amounts of straw ingested and increased feed intake due to increased stimulation of exploratory behaviour with increasing amounts of straw available, or a combination of these. The observed tendency for a higher feed intake supports this suggestion, but studies are needed to establish the impact of these two contributing factors.
Tail biting is a welfare and economical concern in modern pig production. One common preventive measure used throughout the world is tail docking, which is generally considered one of the most effective methods for limiting tail biting. However, tail docking is a painful mutilation and systematic tail docking is not allowed in the EU. Therefore, the aim was to compare pig behaviour and the prevalence of tail biting in finishing pigs with intact tails housed in two different pen designs under Danish commercial conditions. PEN1 was a traditional Danish pen and PEN2 was inspired by Swedish finisher pen design and had a larger proportion of solid floor area (PEN1: 1/3 and PEN2: 2/3), reduced group size (PEN1: 15 and PEN2: 12), increased space allowance per head (PEN1: 0.7 m2 and PEN2: 0.89 m2) and straw allocated on the floor (PEN2) whereas straw was provided in a straw rack in PEN1. Tail damage observations were carried out daily by the stockperson and every 2 weeks one trained research technician assessed tail damages according to a tail scoring system. Tail lesions were observed in 51% of PEN1 and in 11% of PEN2 (P < 0.001). PEN1 had higher prevalence of tail damages than PEN2 (23% v. 5%, P < 0.001). Behavioural observations were carried out by the use of video recordings. Pigs in PEN2 tended to spend more time on tail-directed behaviour than pigs in PEN1 (P = 0.07), whereas pigs in PEN1 tended to spend more time on ear-directed behaviour (P = 0.08). Pigs in PEN2 spent more time on straw-directed behaviour compared to pigs in PEN1 (P < 0.001). Pen design did not affect time spent on other penmate-directed behaviour. In addition, the level of welfare between the two pen designs was compared using the Welfare Quality® protocol. PEN2 received an overall score of ‘excellent’ while PEN1 scored ‘enhanced’. PEN2 scored higher on all principles besides ‘good health’, where PEN1 scored better on lameness and wounds. The main measurements accounting for the differences were water supply, huddling, tail biting, social behaviour and fear of humans. In conclusion, the combination of increased space allowance, increased area of solid flooring, straw allocated onto the floor and reduced group size (PEN2) resulted in fewer tail damaged pigs and a better overall welfare assessment, despite a tendency for more tail-directed behaviour.
Climate and weather conditions may have substantial effects on the ecology of both parasites and hosts in natural populations. The strength and shape of the effects of weather on parasites and hosts are likely to change as global warming affects local climate. These changes may in turn alter fundamental elements of parasite–host dynamics. We explored the influence of temperature and precipitation on parasite prevalence in a metapopulation of avian hosts in northern Norway. We also investigated if annual change in parasite prevalence was related to winter climate, as described by the North Atlantic Oscillation (NAO). We found that parasite prevalence increased with temperature within-years and decreased slightly with increasing precipitation. We also found that a mild winter (positive winter NAO index) was associated with higher mean parasite prevalence the following year. Our results indicate that both local and large scale weather conditions may affect the proportion of hosts that become infected by parasites in natural populations. Understanding the effect of climate and weather on parasite–host relationships in natural populations is vital in order to predict the full consequence of global warming.
There are increasing efforts aiming to utilise endophytes as biological control agents (BCAs) to improve crop production. However, reliability remains a major practical constraint for the development of novel BCAs. Many organisms are adapted to their specific habitat; it is optimistic to expect that a new organism added can find a niche or even out-compete those adapted and already present. Our approach for isolating novel BCAs for specific plant diseases is therefore to look in healthy plants in a habitat where disease is a problem, since we predict that it is more likely to find competitive strains among those present and adapted. In vitro inhibitory activities often do not correlate with in planta efficacy, especially since endophytes rely on intimate plant contact. They can, however, be useful to indicate modes of action. We therefore screen for in planta biological activity as early as possible in the process in order to minimise the risk of discarding valuable strains. Finally, some fungi are endophytic in one situation and pathogenic in another (the mutualism–parasitism continuum). This depends on their biology, environmental conditions, the formulation of inoculum, the health, developmental stage and cultivar of the host plant, and the structure of the plant microbiome.
We consider an infinitely divisible random field in ℝd given as an integral of a kernel function with respect to a Lévy basis. Under mild regularity conditions, we derive central limit theorems for the moment estimators of the mean and the variogram of the field.
The detection and monitoring of meltwater within firn presents a significant monitoring challenge. We explore the potential of small wireless sensors (ETracer+, ET+) to measure temperature, pressure, electrical conductivity and thus the presence or absence of meltwater within firn, through tests in the dry snow zone at the East Greenland Ice Core Project site. The tested sensor platforms are small, robust and low cost, and communicate data via a VHF radio link to surface receivers. The sensors were deployed in low-temperature firn at the centre and shear margins of an ice stream for 4 weeks, and a ‘bucket experiment’ was used to test the detection of water within otherwise dry firn. The tests showed the ET+ could log subsurface temperatures and transmit the recorded data through up to 150 m dry firn. Two VHF receivers were tested: an autonomous phase-sensitive radio-echo sounder (ApRES) and a WinRadio. The ApRES can combine high-resolution imaging of the firn layers (by radio-echo sounding) with in situ measurements from the sensors, to build up a high spatial and temporal resolution picture of the subsurface. These results indicate that wireless sensors have great potential for long-term monitoring of firn processes.
Experiments with a weakly damped monopile, either fixed or free to oscillate, exposed to irregular waves in deep water, obtain the wave-exciting moment and motion response. The nonlinearity and peak wavenumber cover the ranges:
is an estimate of the spectral wave slope,
the significant wave height,
the peak wavenumber and
the cylinder radius. The response and its statistics, expressed in terms of the exceedance probability, are discussed as a function of the resonance frequency,
in the range
times the spectral peak frequency,
. For small wave slope, long waves and
, the nonlinear response deviates only very little from its linear counterpart. However, the nonlinearity becomes important for increasing wave slope, wavenumber and resonance frequency ratio. The extreme response events are found in a region where the Keulegan–Carpenter number exceeds
, indicating the importance of possible flow separation effects. A similar region is also covered by a Froude number exceeding
, pointing to surface gravity wave effects at the scale of the cylinder diameter. Regarding contributions to the higher harmonic forces, different wave load mechanisms are identified, including: (i) wave-exciting inertia forces, a function of the fluid acceleration; (ii) wave slamming due to both non-breaking and breaking wave events; (iii) a secondary load cycle; and (iv) possible drag forces, a function of the fluid velocity. Also, history effects due to the inertia of the moving pile, contribute to the large response events. The ensemble means of the third, fourth and fifth harmonic wave-exciting force components extracted from the irregular wave results are compared to the third harmonic FNV (Faltinsen, Newman and Vinje) theory as well as other available experiments and calculations. The present irregular wave measurements generalize results obtained in deep water regular waves.
Laboratory experiments with a bottom hinged surface-piercing cylinder, exposed to irregular deep water waves, are used to investigate high-frequency forcing. The focus is on the secondary load cycle, a strongly nonlinear phenomenon regarding the wave load on a vertical cylinder, first identified by Grue et al. (1993 Preprint Series. Mechanics and Applied Mathematics, pp. 1–30. University of Oslo, available at http://urn.nb.no/URN:NBN:no-52740; 1994 Ninth International Workshop on Water Waves and Floating Bodies (ed. M. Ohkusu), pp. 77–81, available at http://iwwwfb.org). For a total of 2166 single wave events, the force above
is the governing wave frequency) is used to identify and split the strongly nonlinear forces into two peaks: a high-frequency peak closely correlated in time with the wave crest when the total load is positive and a high-frequency peak defining the secondary load cycle which occurs close in time to the wave zero downcrossing when the total load is negative. The two peaks are studied by regression analysis as a function of either the Keulegan–Carpenter number (
) or the Froude number (
). Regarding the secondary load cycle, the best correlation is found with
. The speed of the travelling edge of the undisturbed wave approximates the fluid velocity. A threshold value separating between small and large forces is found for
–5, indicating effects of flow separation. Alternatively, the threshold occurs for
–0.4, indicating local wave effects at the scale of the cylinder diameter. The findings suggest that both effects are present and important.
Engabreen is an outlet glacier of the Svartisen Ice Cap located in Northern Norway. It is a unique glacier due to the Svartisen Subglacial Laboratory which allows direct access to the glacier bed. In this study, we combine both sub- and supraglacial observations with ice-flow modelling in order to investigate conditions at the bed of Engabreen both spatially and temporally. We use the full-Stokes model Elmer/Ice and satellite-based surface-velocity maps from 2010 and 2014 to infer patterns of basal friction. Direct measurements of basal sliding and deformation of lower layers of the ice are used to adjust the ice viscosity and provide essential input to the setup of our model and influence the interpretation of the results. We find a clear seasonal cycle in the subglacial conditions at the higher elevation region of the study area and discuss this in relation to the subglacial hydrological system. Our results also reveal an area with an overdeepening where basal friction is significantly lower than elsewhere on the glacier all year round. We attribute this to either water pooling at the base, or saturated sediments and increased strain heating at this location which softens the ice further.
Community-acquired bacteraemia patients (n = 2472), Denmark, 2000–2008. Albumin, C-reactive protein (CRP) and haemoglobin (Hb) measured 2000–2010. We assessed daily mean levels of albumin, CRP and Hb from 30 days before to 30 days after bacteraemia and correlations between albumin vs. CRP and albumin vs. Hb. In linear regression models, we evaluated the contribution of CRP, Hb, chronic and acute variables to the albumin level variations. The mean albumin level (33.6 g/l) was steady before day 1, declined to 29.3 g/l on day 1 with little increase afterward. The mean CRP increased from day −5, peaked on day 1 and declined thereafter. The mean Hb level was fairly constant during days −30/30. Albumin was inversely (R range, − 0.18/–0.47, P < 10−4) correlated with the CRP level and positively (R = 0.17–0.46, P < 10−4) correlated with the HB level. In most models, CRP was the first variable that contributed to the albumin variations, 34–70% of the full model. The sudden decrease of albumin levels, without sudden fluctuations of CRP or Hb, indicated that hypoalbuminaemia was a marker of trans-capillary leakage.
We consider a continuous, infinitely divisible random field in ℝd, d = 1, 2, 3, given as an integral of a kernel function with respect to a Lévy basis with convolution equivalent Lévy measure. For a large class of such random fields, we compute the asymptotic probability that the excursion set at level x contains some rotation of an object with fixed radius as x → ∞. Our main result is that the asymptotic probability is equivalent to the right tail of the underlying Lévy measure.
Flavonoids are bioactive compounds found in foods such as tea, red wine, fruits and vegetables. Higher intakes of specific flavonoids, and flavonoid-rich foods, have been linked to reduced mortality from specific vascular diseases and cancers. However, the importance of flavonoid-rich foods, and flavonoids, in preventing all-cause mortality remains uncertain. As such, we examined the association of intake of flavonoid-rich foods and flavonoids with subsequent mortality among 93 145 young and middle-aged women in the Nurses’ Health Study II. During 1 838 946 person-years of follow-up, 1808 participants died. When compared with non-consumers, frequent consumers of red wine, tea, peppers, blueberries and strawberries were at reduced risk of all-cause mortality (P<0·05), with the strongest associations observed for red wine and tea; multivariable-adjusted hazard ratios 0·60 (95 % CI 0·49, 0·74) and 0·73 (95 % CI 0·65, 0·83), respectively. Conversely, frequent grapefruit consumers were at increased risk of all-cause mortality, compared with their non-grapefruit consuming counterparts (P<0·05). When compared with those in the lowest consumption quintile, participants in the highest quintile of total-flavonoid intake were at reduced risk of all-cause mortality in the age-adjusted model; 0·81 (95 % CI 0·71, 0·93). However, this association was attenuated following multivariable adjustment; 0·92 (95 % CI 0·80, 1·06). Similar results were observed for consumption of flavan-3-ols, proanthocyanidins and anthocyanins. Flavonols, flavanones and flavones were not associated with all-cause mortality in any model. Despite null associations at the compound level and select foods, higher consumption of red wine, tea, peppers, blueberries and strawberries, was associated with reduced risk of total and cause-specific mortality. These findings support the rationale for making food-based dietary recommendations.
This study used four waves of data from a longitudinal study of 749 Mexican origin youths to test a developmental cascades model linking contextual adversity in the family and peer domains in late childhood to a sequence of unfolding processes hypothesized to predict problem substance use and risky sexual activity (greater number of sex partners) in late adolescence. Externalizing and internalizing problems were tested as divergent pathways, with youth-reported and mother-reported symptoms examined in separate models. Youth gender, nativity, and cultural orientation were tested as moderators. Family risk, peer social rejection, and their interaction were prospectively related to externalizing symptoms and deviant peer involvement, although family risk showed stronger effects on parent-reported externalizing and peer social rejection showed stronger effects on youth-reported externalizing. Externalizing symptoms and deviant peers were related, in turn, to risk taking in late adolescence, including problem alcohol–substance use and number of sexual partners. Peer social rejection predicted youth-reported internalizing symptoms, and internalizing was related, in turn, to problem alcohol and substance use in late adolescence. Tests of moderation showed some of these developmental cascades were stronger for adolescents who were female, less oriented to mainstream cultural values, and more oriented to Mexican American cultural values.
Recent studies have highlighted the threat that climate change poses to species, as areas of climatic suitability contract or shift across the landscape. North American Neotropical long-distant migrant bird species present a unique problem compared to sedentary species because climate change may differ significantly across their breeding and wintering grounds. Studying the potential future distributions of these birds is challenging on many levels, including the fact that our understanding of the wintering grounds of these species is quite poor. To address this issue, we analyse available eBird data during the winter season in the Western Hemisphere in an effort to further promote and direct citizen science efforts to focus on areas that are climatically undersampled. We used Mobility-Oriented Parity (MOP) to understand the areas where climates are most dissimilar from climates sampled by existing eBird checklists, creating a map that ranks the western hemisphere at a 10 km resolution for climatic sampling during the winter season. We found that parts of Mexico and Central America, areas of Colombia, almost the entire Amazon Basin, coastal Peru and Chile, and northern Argentina are climatically undersampled. As a test case, we then used the map of survey priorities to simulate additional sampling in Colombia and recalculated the rankings. Guiding additional sampling with the priorities reduced climate dissimilarities between sampled and unsampled grid cells more than when additional sampling expanded in proportion to current sampling efforts or based on geographic undersampling. Analyses of sampling coverage in environmental space, such as this, will be a useful tool for targeting monitoring effort for bird species.
In developing countries with limited access to ENT services, performing emergency cricothyroidotomy in patients with upper airway obstruction may be a life-saving last resort. An established Danish–Zimbabwean collaboration of otorhinolaryngologists enrolled Zimbabwean doctors into a video-guided simulation training programme on emergency cricothyroidotomy. This paper presents the positive effect of this training, illustrated by two case reports.
A 56-year-old female presented with upper airway obstruction due to a rapidly progressing infectious swelling of the head and neck progressing to cardiac arrest. Cardiopulmonary resuscitation was initiated and a secure surgical airway was established via an emergency cricothyroidotomy, saving the patient. A 70-year-old male presented with upper airway obstruction secondary to intubation for an elective procedure. When extubated, the patient exhibited severe stridor followed by respiratory arrest. Re-intubation attempts were unsuccessful and emergency cricothyroidotomy was performed to secure the airway, preserving the life of the patient.
Emergency cricothyroidotomy training should be considered for all surgeons, anaesthetists and, eventually, emergency and recovery room personnel in developing countries. A video-guided simulation training programme on emergency cricothyroidotomy in Zimbabwe proved its value in this regard.
Human milk decreases the risk of necrotising enterocolitis (NEC), a severe gastrointestinal disease that occurs in 5–10 % of preterm infants. The prebiotic and immune-modulatory effects of milk oligosaccharides may contribute to this protection. Preterm pigs were used to test whether infant formula enriched with α1,2-fucosyllactose (2'-FL, the most abundant oligosaccharide in human milk) would benefit gut microbial colonisation and NEC resistance after preterm birth. Caesarean-delivered preterm pigs were fed formula (Controls, n 17) or formula with 5 g/l 2'-FL (2'-FL, n 16) for 5 d; eight 2'-FL pigs (50 %) and twelve Controls (71 %) developed NEC, with no difference in lesion scores (P=0·35); 2'-FL pigs tended to have less anaerobic bacteria in caecal contents (P=0·22), but no difference in gut microbiota between groups were observed by fluorescence in situ hybridisation and 454 pyrosequencing. Abundant α1,2-fucose was detected in the intestine with no difference between groups, and intestinal structure (villus height, permeability) and digestive function (hexose absorption, brush border enzyme activities) were not affected by 2'-FL. Formula enrichment with 2'-FL does not affect gut microbiology, digestive function or NEC sensitivity in pigs within the first few days after preterm birth. Milk 2'-FL may not be critical in the immediate postnatal period of preterm neonates when gut colonisation and intestinal immunity are still immature.
Mutants of Bacillus subtilis can be developed to overproduce Val in vitro. It was hypothesized that addition of Bacillus subtilis mutants to pig diets can be a strategy to supply the animal with Val. The objective was to investigate the effect of Bacillus subtilis mutants on growth performance and blood amino acid (AA) concentrations when fed to piglets. Experiment 1 included 18 pigs (15.0±1.1 kg) fed one of three diets containing either 0.63 or 0.69 standardized ileal digestible (SID) Val : Lys, or 0.63 SID Val : Lys supplemented with a Bacillus subtilis mutant (mutant 1). Blood samples were obtained 0.5 h before feeding and at 1, 2, 3, 4, 5 and 6 h after feeding and analyzed for AAs. In Experiment 2, 80 piglets (9.1±1.1 kg) were fed one of four diets containing 0.63 or 0.67 SID Val : Lys, or 0.63 SID Val : Lys supplemented with another Bacillus subtilis mutant (mutant 2) or its parent wild type. Average daily feed intake, daily weight gain and feed conversion ratio were measured on days 7, 14 and 21. On day 17, blood samples were taken and analyzed for AAs. On days 24 to 26, six pigs from each dietary treatment were fitted with a permanent jugular vein catheter, and blood samples were taken for AA analysis 0.5 h before feeding and at 1, 2, 3, 4, 5 and 6 h after feeding. In experiment 1, Bacillus subtilis mutant 1 tended (P<0.10) to increase the plasma levels of Val at 2 and 3 h post-feeding, but this was not confirmed in Experiment 2. In Experiment 2, Bacillus subtilis mutant 2 and the wild type did not result in a growth performance different from the negative and positive controls. In conclusion, results obtained with the mutant strains of Bacillus subtilis were not better than results obtained with the wild-type strain, and for both strains, the results were not different than the negative control.
We consider a continuous, infinitely divisible random field in Rd given as an integral of a kernel function with respect to a Lévy basis with convolution equivalent Lévy measure. For a large class of such random fields we compute the asymptotic probability that the supremum of the field exceeds the level x as x → ∞. Our main result is that the asymptotic probability is equivalent to the right tail of the underlying Lévy measure.