314 research outputs found
The effect of timing of oral meloxicam administration on physiological responses in calves after cautery dehorning with local anesthesia.
Abstract Dehorning is a painful husbandry procedure that is commonly performed in dairy calves. Parenteral meloxicam combined with local anesthesia mitigates the physiological and behavioral effects of dehorning in calves. The purpose of this study was to determine the influence of timing of oral meloxicam administration on physiological responses in calves after dehorning. Thirty Holstein bull calves, 8 to 10 wk of age (28–70kg), were randomly assigned to 1 of 3 treatment groups: placebo-treated control group (n=10), calves receiving meloxicam administered orally (1 mg/kg) in powdered milk replacer 12h before cautery dehorning (MEL-PRE; n=10), and calves receiving meloxicam administered as an oral bolus (1 mg/kg) at the time of dehorning (MEL-POST; n=10). Following cautery dehorning, blood samples were collected to measure cortisol, substance P (SP), haptoglobin, ex vivo prostaglandin E 2 (PgE 2 ) production after lipopolysaccharide stimulation and meloxicam concentrations. Maximum ocular temperature and mechanical nociceptive threshold (MNT) were also assessed. Data were analyzed using noncompartmental pharmacokinetic analysis and repeated measures ANOVA models. Mean peak meloxicam concentrations were 3.61±0 0.21 and 3.27±0.14μg/mL with average elimination half-lives of 38.62±5.87 and 35.81±6.26h for MEL-PRE and MEL-POST, respectively. Serum cortisol concentrations were lower in meloxicam-treated calves compared with control calves at 4h postdehorning. Substance P concentrations were significantly higher in control calves compared with meloxicam-treated calves at 120h after dehorning. Prostaglandin E 2 concentrations were lower in meloxicam-treated calves compared with control calves. Mechanical nociceptive threshold was higher in control calves at 1h after dehorning, but meloxicam-treated calves tended to have a higher MNT at 6h after dehorning. No effect of timing of meloxicam administration on serum cortisol concentrations, SP concentrations, haptoglobin concentrations, maximum ocular temperature, or MNT was observed. However, PgE 2 concentrations in MEL-PRE calves were similar to control calves after 12h postdehorning, whereas MEL-POST calves had lower PgE 2 concentrations for 3 d postdehorning. These findings support that meloxicam reduced cortisol, SP, and PgE 2 after dehorning, but only PgE 2 production was significantly affected by the timing of meloxicam administration
Do position and species identity of neighbours matter in 8–15-year-old post harvest mesic stands in the boreal mixedwood?
Neighbourhood competition indices (NCI), where position and species identity of neighbours are known, have been used to investigate growth and competitive interactions among adult trees. In this study, we used NCI in 8–15-year-old stands following clear-cutting in a boreal mixedwood forest of eastern Canada to improve our understanding of early successional forest dynamics. Trees of increasing diameter from the center (≥1 cm) to the edge (≥5 cm) were mapped in twenty-five circular 450m2 plots. Target trees (DBH≥1 cm) were sampled in plot center to determine their annual radial stem growth. For each species, we compared a set of growth models using either a spatially explicit NCI or a non-spatial competition index. Both types of indices estimated a species-specific competition coefficient for each pair of competitor–target species. NCI were selected as the best competition model for all target species although differences in variance explained relative to the non-spatial index were small. This likely indicates that competition occurs at the local level but that the high density and the relative uniformity of these young stands creates similar neighbourhoods for most trees in a given stand. The effective neighbourhood radius for competitors varied among species and was smaller for shade tolerant species. Intraspecific neighbours were the strongest competitors for most species. Aspen (Populus tremuloides) was a weak competitor for all species as opposed to balsam fir (Abies balsamea) which was a strong competitor in all cases. These results are in contradiction with some widely used forest policies in North America (e.g. free-to-grow standards) that consider broadleaf species, such as aspen, as the strongest competitors. For these early successional forests, the decision regarding the use of spatial or non-spatial competition indices should rest on the intended use. For even-age management, spatial indices might not justify their use in highdensity stands but they are needed for the simulation of novel harvest techniques creating complex stand structure
The spin angular gradient approximation in the density functional theory
A spin angular gradient approximation for the exchange correlation magnetic
field in the density functional formalism is proposed. The usage of such
corrections leads to a consistent spin dynamical approach beyond the local
approximation. The proposed technique does not contain any approximations for
the form of potential and can be used in modern full potential band structure
methods. The obtained results indicate that the direct 'potential' exchange in
3d magnets is rather small compared to the indirect 'kinetic' exchange, thus
justifies the dynamical aspect of the local density approximation in 3d metals
Knowledge and Opinions of Third Year Veterinary Students Relevant to Animal Welfare Before and After Implementation of a Core Welfare Course
Although leading veterinary organizations emphasize the importance of animal welfare knowledge, there exists a gap in current veterinary student animal welfare education and training. A survey instrument was created to assess third-year Doctor of Veterinary Medicine (DVM) student knowledge of key animal welfare topics, opinions regarding the inclusion of welfare education in the veterinary curriculum, and views on veterinarian responsibilities as advocates. In Spring 2018, Colorado State University added a required animal welfare course to the DVM curriculum. Pre- and post-course paper surveys were distributed to the third-year students enrolled in the animal welfare course. One hundred thirty one completed pre-course surveys were collected and 125 completed post-course surveys were collected. Of the pre and post-course surveys collected, 61 were paired with identification codes and utilized for statistical comparison. Results indicated that the course led students to view the inclusion of an animal welfare course in the veterinary curriculum more favorably (p = 0.009) and improved their confidence in conducting research on animal welfare topics (p < 0.001). The course did not change students' sense of responsibility toward welfare advocacy. Associations were not found between attitudes toward these issues and demographic variables of home community, respondent gender, and track selection (p > 0.06). Veterinarians were consistently ranked by students as the most influential member of a community in matters of animal welfare. Future research on the lack of veterinary student knowledge of animal welfare should be done on a national scale to facilitate strategic development of mandatory animal welfare courses in veterinary curricula. Future research should be designed to gain knowledge regarding DVM students' opinions and attitudes regarding effective methods of incorporating animal welfare education into their professional training
The impact of maternal BMI status on pregnancy outcomes with immediate short-term obstetric resource implications : a meta-analysis.
Obesity is rising in the obstetric population, yet there is an absence of services and guidance for the management of maternal obesity. This systematic review aimed to investigate relationships between obesity and impact on obstetric care. Literature was systematically searched for cohort studies of pregnant women with anthropometric measurements recorded within 16-weeks gestation, followed up for the term of the pregnancy, with at least one obese and one comparison group. Two researchers independently data-extracted and quality-assessed each included study. Outcome measures were those that directly or indirectly impacted on maternity resources. Primary outcomes included instrumental delivery, caesarean delivery, duration of hospital stay, neonatal intensive care, neonatal trauma, haemorrhage, infection and 3rd/4th degree tears. Meta-analysis shows a significant relationship between obesity and increased odds of caesarean and instrumental deliveries, haemorrhage, infection, longer duration of hospital stay and increased neonatal intensive care requirement. Maternal obesity significantly contributes to a poorer prognosis for mother and baby during delivery and in the immediate post-partum period. National clinical guidelines for management of obese pregnant women, and public health interventions to help safeguard the health of mothers and their babies are urgently required
Investigating the carbon isotope composition and leaf wax n-alkane concentration of C3 and C4 plants in Stiffkey saltmarsh, Norfolk, UK
The carbon isotope composition of terrestrial plants records valuable ecophysiological and palaeoecological information. However, interspecies variability in 13C/12C, at both the bulk and compound-specific (CS) level, requires further exploration across a range of ecosystem types. Here, we present bulk and n-alkane δ13C values, and n-alkane concentrations, from seven plants (C3 and C4) growing in a temperate UK saltmarsh. Inter- and intra-species variation in n-alkane δ13C values among C3 plants ranged from 8‰ (n-C31) to 10‰ (n-C27) across the 2011 and 2012 growing seasons, exceeding variability in bulk tissue (7‰). In contrast, the C4 monocot showed < 2‰ seasonal shifts in bulk and CS values. As a result of the variability in our CS data, we calculate that n-alkane based C3/C4 reconstructions in temperate saltmarshes have a maximum uncertainty of ∼11%. For dicots and succulents, seasonal bulk and CS δ13C trends diverged, while for C3 and C4 monocots, bulk and CS values followed similar temporal patterns. Fractionation between bulk and n-alkane carbon isotope values varied from −4 to −10‰ for C3 plants, and reached −13‰ for the C4 monocot. We explain discrepancies between bulk and n-alkane δ13C values by referring to possible interspecies variation in salinity adaptation, which may influence the partitioning of pyruvate, shifting the isotopic composition of lipid biomarkers. These findings open new avenues for empirical studies to further understand the metabolic processes fractionating carbon during the synthesis of n-alkanes, enhancing interpretation of the biomarker signal from the geological record
Genetic dissection of an amygdala microcircuit that gates conditioned fear
The role of different amygdala nuclei (neuroanatomical subdivisions) in processing Pavlovian conditioned fear has been studied extensively, but the function of the heterogeneous neuronal subtypes within these nuclei remains poorly understood. Here we use molecular genetic approaches to map the functional connectivity of a subpopulation of GABA-containing neurons, located in the lateral subdivision of the central amygdala (CEl), which express protein kinase C-δ (PKC-δ). Channelrhodopsin-2-assisted circuit mapping in amygdala slices and cell-specific viral tracing indicate that PKC-δ^+ neurons inhibit output neurons in the medial central amygdala (CEm), and also make reciprocal inhibitory synapses with PKC-δ^− neurons in CEl. Electrical silencing of PKC-δ^+ neurons in vivo suggests that they correspond to physiologically identified units that are inhibited by the conditioned stimulus, called Cel_(off) units. This correspondence, together with behavioural data, defines an inhibitory microcircuit in CEl that gates CEm output to control the level of conditioned freezing
Proteomic analysis of Salmonella enterica serovar Enteritidis following propionate adaptation
<p>Abstract</p> <p>Background</p> <p><it>Salmonella </it>Enteritidis is a highly prevalent and persistent foodborne pathogen and is therefore a leading cause of nontyphoidal gastrointestinal disease worldwide. A variety of stresses are endured throughout its infection cycle, including high concentrations of propionate (PA) within food processing systems and within the gut of infected hosts. Prolonged PA exposure experienced in such milieus may have a drastic effect on the proteome of <it>Salmonella </it>Enteritidis subjected to this stress.</p> <p>Results</p> <p>In this study, we used 2 D gel electrophoresis to examine the proteomes of PA adapted and unadapted <it>S</it>. Enteritidis and have identified five proteins that are upregulated in PA adapted cultures using standard peptide mass fingerprinting by MALDI-TOF-MS and sequencing by MALDI LIFT-TOF/TOF tandem mass spectrometry. Of these five, two significant stress-related proteins (Dps and CpxR) were shown (via qRT-PCR analysis) to be upregulated at the transcriptional level as well. Unlike the wild type when adapted to PA (which demonstrates significant acid resistance), PA adapted <it>S</it>. Enteritidis ∆<it>dps </it>and <it>S</it>. Enteritidis ∆<it>cpxR </it>were at a clear disadvantage when challenged to a highly acidic environment. However, we found the acid resistance to be fully restorable after genetic complementation.</p> <p>Conclusions</p> <p>This work reveals a significant difference in the proteomes of PA adapted and unadapted <it>S</it>. Enteritidis and affirms the contribution of Dps and CpxR in PA induced acid resistance.</p
An ensemble of flexible conformations underlies mechanotransduction by the cadherin-catenin adhesion complex
© 2019 The Authors. Published by National Academy of Sciences. This is an open access article available under a Creative Commons licence.
The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.1073/pnas.1911489116The cadherin–catenin adhesion complex is the central component of the cell–cell adhesion adherens junctions that transmit mechanical stress from cell to cell. We have determined the nanoscale structure of the adherens junction complex formed by the α-catenin•β-catenin•epithelial cadherin cytoplasmic domain (ABE) using negative stain electron microscopy, small-angle X-ray scattering, and selective deuteration/small-angle neutron scattering. The ABE complex is highly pliable and displays a wide spectrum of flexible structures that are facilitated by protein-domain motions in α- and β-catenin. Moreover, the 107-residue intrinsically disordered N-terminal segment of β-catenin forms a flexible “tongue” that is inserted into α-catenin and participates in the assembly of the ABE complex. The unanticipated ensemble of flexible conformations of the ABE complex suggests a dynamic mechanism for sensitivity and reversibility when transducing mechanical signals, in addition to the catch/slip bond behavior displayed by the ABE complex under mechanical tension. Our results provide mechanistic insight into the structural dynamics for the cadherin–catenin adhesion complex in mechanotransduction.This research was funded by NSF Grant MCB-1817684 (to Z.B.) and National Center for Research Resources Grant 2G12 RR003060 (to City College of New York). A portion of the research conducted at Oak Ridge National Laboratory’s Spallation Neutron Source and High Flux Isotope Reactor was sponsored by the Scientific User Facilities Division, Office of Basic Energy Sciences, US Department of Energy (DOE). The Bio-SANS of the Center for Structural Molecular Biology at the High Flux Isotope Reactor is supported by the Office of Biological and Environmental Research of the DOE. Use of the SSRL, Stanford Linear Accelerator Center’s is supported by DOE, Office of Science, Office of Basic Energy Sciences Contract DE-AC02-76SF00515. The SSRL Structural Molecular Biology Program is supported by the DOE Office of Biological and Environmental Research and NIH, National Institute of General Medical Sciences (NIGMS) Grant P41 GM103393.Published versio
Alternative farrowing accommodation: welfare and economic aspects of existing farrowing and lactation systems for pigs
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