Neuroendocrine Reactivity During the Naturalistic Stress of an Outward Bound Course

Recent studies have found that subjects with high hostility propensity have greater catecholamine (CA) and cortisol (Cf) levels during laboratory stressors. The present investigation sought to determine if similar patterns would be found in the naturalistic setting of an Outward Bound experience, and if high versus low aerobic fitness would influence CA and CT levels in this setting. Sixty-six individuals volunteered for the study from participants who had registered for a nine-day \u27adult intensive\u27 Outward Bound course. Thirty-one subjects were selected from those who volunteered. The Cook-Medley Hostility Inventory was completed by each subject prior to arriving for their course and aerobic fitness estimates were completed within the first six hours of the course using the University of Houston Non-Exercise Test Stress levels were quantified by urinary CA and CT excretion. Three to five hour urine samples were collected for the following activities: rockclimbing/rappelling, whitewater canoeing, ropes course, off-trail backpacking, commuting from airport to base camp and back, and one night-time sleep sample. At the beginning of each activity period, all subjects voided and at the end of the three to five hour period urine was collected, measured for total volume, and a sample was taken and ftw.en within two hours of collection. The urine was assayed by high-pressure liquid chromatography with electrochemical detection to determine levels of excreted epinephrine (E), norepinephrine (NE), and cortisol (CT). The CA and CT were then quantified by mg of creatinine. Of the 31 subjects (14 females and 17 males), nine were classfied as high hostile (HiHo) and 22 as average to low hostile (LoHo). The classifications for aerobic fitness were: 26 average to high fit (HF) with an estimated max V02 greater than 39 ml/kg for women and 46 ml/kg for men, and five low fit (LF) subjects with lower estimated V02 max. The data were analyzed by the two levels of hostility and two levels of aerobic fitness using univariate ANOVA with repeated measures across activity periods. The analysis of hostility revealed significant CT excretion differences between hostility levels for four of the nine activity periods with the LoHo subjects excreting higher CT levels. The four activities where this was found were: off-trail backpacking, (F=4.74,

Commercial hatchery practices have long-lasting effects on laying hens' spatial behaviour and health.

The commercial hatchery process is globally standardized and exposes billions of day-old layer chicks to stress every year. By alleviating this early stress, on-farm hatching is thought to improve animal welfare, yet little is known about its effects throughout production. This study compared welfare indicators and spatial behaviours during the laying period of hens hatched in an on-farm environment (OFH) to those hatched in a commercial hatchery and transferred at one day-old to a rearing barn (STAN). In particular, we assessed how OFH and TRAN hens differed in space-use and movement behaviours following the transfer to the laying barn at 17 weeks of age, a similar stressor encountered by STAN hens early in life, and determined whether effects aligned more with the 'silver-spoon' or 'environmental matching' hypothesis. We found that for the first three months post-transfer into the laying barn, OFH hens, on average, transitioned less between the aviary's tiers and spent less time on the littered floor. Because OFH hens became behaviourally more similar to STAN hens over time, these results suggest that OFH hens required a prolonged period to establish their daily behavioural patterns. Furthermore, OFH hens had more severe keel bone fractures throughout the laying period but similar feather damage and body mass to STAN hens. No differences were found in hen mortality or the number of eggs per live hen. These findings support the environmental matching hypothesis and suggest that early-life stressors may have prepared hens for later-life stressors, underscoring the importance of both early-life and adult environments in enhancing animal welfare throughout production

Editor\u27s Introduction and Acknowledgments

An introduction to the journal Research in Outdoor Education, volume 7 is presented by the authors on behalf of the Coalition for Education in the Outdoors (CEO) Research Committee

Keel bone fractures affect laying hens' mobility, but no evidence for reciprocal effects.

Keel bone fractures (KBF) are prevalent in commercial laying hens and are considered one of the greatest welfare concerns in the egg-production industry. While clear associations exist between KBF and animal mobility, suggesting that KBF impair mobility, the effect of mobility on KBF remains unclear. We combined data from three studies that assessed keel bone fracture severity through radiographs and monitored hens' transitions between different zones of a multi-tier aviary system (the three tiers, a littered floor, and a winter garden) the week prior to radiograph. For each hen, we extracted two daily movement behaviours: the vertical distance travelled and the mean number of zones crossed within one transition; and two daily space-use behaviours: the time spent in the top tier and the unevenness of time spent across zones. We used hierarchical Bayesian continuous time dynamic modelling to estimate how a change in a behaviour predicted a later change in keel bone fracture severity, and vice versa. Increased fracture severity did not predict later changes in space-use behaviours, but it did predict changes in movement behaviours. Specifically, increased fracture severity led to decreased vertical travelled distance and a tendency to cross more zones within one transition, suggesting impaired mobility in hens with increased fracture severity. In contrast, we found no evidence that movement or space-use behaviours predict later change in fracture severity, challenging previous literature suggesting that vertical locomotion through jumping and flying may exacerbate keel bone fractures in complex three-dimensional systems due to increased risk of collisions. However, similar efforts accounting for the location of fractures on the keel could unveil the potential influence of movement and space-use behaviours in the formation and change (healing or worsening) of KBF and increase our ability to mitigate their effects

Intra-individual variation of hen movements is associated with later keel bone fractures in a quasi-commercial aviary.

Measuring intra- and inter-individual variation in movement can bring important insights into the fundamental ecology of animals and their welfare. Although previous studies identified consistent differences in movements of laying hens within commercial aviaries, the level of consistency was not quantified, limiting our capacity to understand the importance of individual movements for welfare. We aimed to quantify the scope of intra- and inter-individual differences in movements of commercial laying hens and examined their associations with indicators of welfare at the end of production. We quantified individual differences in one composite daily movement score for 80 hens over 54 days post-transfer to a quasi-commercial aviary. Results showed consistent inter-individual differences in movement averages, explaining 44% of the variation, as well as individual variation in predictability and temporal plasticity (at the population-level, hens increased their movements for 39 days). Hens that were more predictable in their daily movements had more severe keel bone fractures at the end of production while we found no such correlation between daily movement averages (individual intercept) and welfare indicators. Our findings highlight the importance of inter-individual difference in intra-individual variation of movements to improve poultry welfare

Multivariate analysis of morphology, behaviour, growth and developmental timing in hybrids brings new insights into the divergence of sympatric Arctic charr morphs

This work was fully funded by the Icelandic Centre of Research, RANNÍS (Icelandic Research Fund grant no.173802-051).Background: Studying the development of fitness related traits in hybrids from populations diverging in sympatry is a fundamental approach to understand the processes of speciation. However, such traits are often affected by covariance structures that complicate the comprehension of these processes, especially because the interactive relationships between traits of different nature (e.g. morphology, behaviour, life-history) remain largely unknown in this context. In a common garden setup, we conducted an extensive examination of a large suit of traits putatively involved in the divergence of two morphs of Arctic charr (Salvelinus alpinus), and investigated the consequences of potential patterns of trait covariance on the phenotype of their hybrids. These traits were measured along ontogeny and involved growth, yolk sac resorption, developmental timing (hatching and the onset of exogeneous feeding), head morphology and feeding behaviour. Results: Growth trajectories provided the strongest signal of phenotypic divergence between the two charr. Strikingly, the first-generation hybrids did not show intermediate nor delayed growth but were similar to the smallest morph, suggesting parental biases in the inheritance of growth patterns. However, we did not observe extensive multivariate trait differences  between the two morphs and their hybrids. Growth was linked to head morphology (suggesting that morphological variations in early juveniles relate to simple allometric effects) but this was the only strong signal of covariance observed between all the measured traits. Furthermore, we did not report evidence for differences in overall phenotypic variance between morphs, nor for enhanced phenotypic variability in their hybrids. Conclusion: Our study shed light on the multivariate aspect of development in a context of adaptive divergence. The lack of evidence for the integration of most traits into a single covariance structure suggested that phenotypic constraints may not always favour nor impede divergence toward ecological niches differing in numerous physical and ecological variables, as observed in the respective habitats of the two charr. Likewise, the role of hybridization as a disruptive agent of trait covariance may not necessarily be significant in the evolution of populations undergoing resource polymorphism.Publisher PDFPeer reviewe

Integrating Remote Sensing with Ground-based Observations to Quantify the Effects of an Extreme Freeze Event on Black Mangroves (Avicennia germinans) at the Landscape Scale

Climate change is altering the frequency and intensity of extreme weather events. Quantifying ecosystem responses to extreme events at the landscape scale is critical for understanding and responding to climate-driven change but is constrained by limited data availability. Here, we integrated remote sensing with ground-based observations to quantify landscape-scale vegetation damage from an extreme climatic event. We used ground- and satellite-based black mangrove (Avicennia germinans) leaf damage data from the northern Gulf of Mexico (USA and Mexico) to examine the effects of an extreme freeze in a region where black mangroves are expanding their range. The February 2021 event produced coastal temperatures as low as − 10 °C in some areas, exceeding thresholds for A. germinans damage and mortality. We used Sentinel-2 surface reflectance data to assess vegetation greenness before and after the freeze, along with ground-based observations of A. germinans leaf damage. Our results show a negative, nonlinear threshold relationship between A. germinans leaf damage and minimum temperature, with a temperature threshold for leaf damage near − 6 °C. Satellite-based analyses indicate that, at the landscape scale, damage was particularly severe along the central Texas coast, where the freeze event affected \u3e 2000 ha of A. germinans-dominated coastal wetlands. Our analyses highlight the value of pairing remotely sensed data with regional, ground-based observations for quantifying and extrapolating the effects of extreme freeze events on mangroves and other tropical, cold-sensitive plants. The results also demonstrate how extreme freeze events govern the expansion and contraction of mangroves near northern range limits in North America

Confidence Level Of Primary Care Providers In Authorizing Athletic Return-To-Play

The purpose of this study was to identify the level of confidence for primary care providers in authorizing athletic retum-to-play following sports-related injury. The Centers for Disease Control and Prevention (CDC) (as cited in Patel, Yamasaki, & Brown, 2017) reported that 2.6 million children and teens ages 0-19 years are treated annually for sports-related injuries, and 7.2 million high school students participate in sports and suffer an estimated 2 million injuries that require 500,000 doctor visits and 30,000 hospitalizations annually. Although primary care providers are providing care for musculoskeletal and concussive injuries, Benham and Geier (2016) reported that they may not have the confidence, knowledge, or skill to manage common musculoskeletal conditions in their primary care practice. Excellent provisions of such care will require providers who are safe and confident in the management and treatment of sports-related injuries to ensure high-quality patient care (Benham & Geier, 2016). Researchers distributed written surveys, and links to a survey were distributed via social media postings, email, and SurveyMonkey to qualifying participants including Doctors of Medicine (MD), Doctors of Osteopathic Medicine (DO), nurse practitioners (NP), and physician assistants (PA). Data collected indicated that only 47.6% primary care providers were confident with returning youth athletes back-to-play following a sports injury, 34.7% were confident in treating sports-related concussive injuries, and 50% were confident in treating sports-related musculoskeletal injuries. Primary care providers can use this information to expose areas for confidence improvement that can be met with continued education, in-services, and workshops. Schools of medicine and nursing can use these findings to improve musculoskeletal curricula in primary care education. Determining primary care provider confidence level in authorizing athletic retum-to-play is imperative in ensuring patient safety and access to thorough and competent care from initial injury to full resolution