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Data from: Use of environmental sites by mule deer: a proxy for relative risk of chronic wasting disease exposure and transmission

Prions that cause chronic wasting disease (CWD) in cervids can remain infective for years outside the host. Infectious cervids shed prions for a long time, consequently depositing prions in frequently used areas. These environmental prions are important in CWD epidemiology. Unfortunately, effective tools for quantifying CWD prions in soil, water, and other environmental sources are not currently available. Our goal was to investigate relative differences in visits by mule deer (Odocoileus hemionus hemionus) to various environmental site types as an indicator of the relative risk of prion contamination and disease transmission. For this, we deployed a system of triggered-by-movement cameras at eight site types in a CWD-endemic area in Saskatchewan, Canada. We first assessed whether the relative differences among site types in the frequency of visits by mule deer of any sex-and-age class, males, and females varied by season and site type. We then assessed whether the rate of behaviors with a high risk of environmental prion transmission (either contamination or acquisition) differed by season and site type. Finally, we assessed whether the intensity of visitation, based on the number of animals per picture, differed by season and site type. We found that grain sources and beds were key attractants for mule deer: (1) The greatest number of pictures with mule deer per camera-day occurred at grain sources across all seasons, except in fawning, when beds were the most visited sites; (2) during pre-rut and early gestation, mule deer visited grain sources at least twice as often as most other sites; (3) females were more likely to visit beds and grain sources, but there was no significant site preferences for males after accounting for season; (4) mule deer were most likely to be pictured contacting the environment at grain sources in early gestation; and (5) beds and grain sources were the most intensively visited sites. We also found that environmental contacts at waterholes were more frequent during spring. We discuss the potential importance of various sites in the transmission of CWD and how their modification could potentially reduce the risk of prion environmental exposure among mule deer.

opencc-zeroDec 2015View details →

Data from: Maladaptation to acute metal exposure in resurrected Daphnia ambigua clones after decades of increasing contamination

Human environmental impacts have driven some of the strongest and fastest phenotypic changes recorded in wild animal populations. Across populations, this variation is often adaptive, as populations evolve fitness advantages in response to human-modified environments. Yet some populations fail to adapt to changing environments. Evidenced by declines in relative fitness, such seemingly maladaptive outcomes are less common, but may be more likely in human modified contexts. Further, our ability to investigate the dynamics of these adaptive and maladaptive responses over time is typically limited in natural systems. I combined resurrection ecology and paleolimnology approaches to examine evolutionary responses of the freshwater zooplankter Daphnia to exposure to heavy metal contamination over the past 50-75 years using animals hatched from diapausing egg banks. In contrast to the predicted trend of adaptation to metal exposure over time, I observed an increase in sensitivity to both copper and cadmium exposure associated with increasing historic contamination. This potentially maladaptive trend occurred in Daphnia populations in three lakes. Given that the release of toxicants such as heavy metals is widespread and other researchers have observed local maladaptation to toxicant exposure, it is important to understand the drivers and implications of this pattern.

opencc-zeroDec 2014View details →

Data from: Experimental exposure to trace metals affects plumage bacterial community in the feral pigeon

Bacteria are fundamental associates of animals, and recent studies have highlighted their major role in host behaviour, immunity or reproductive investment. Thus, any environmental factor modifying bacterial community may affect host fitness. In birds, trace metals emitted by anthropogenic activities accumulate onto the plumage where they may alter bacterial community and ultimately affect bird fitness. Although trace metals are current major environmental issues in urban habitats, their effects on feather bacterial community have never been investigated. Here, we supplemented feral pigeons Columba livia, an emblematic urban species, with zinc and/or lead in drinking and bath water. As expected, lead and zinc supplementations modified plumage bacterial community composition. Zinc decreased bacterial load, while lead decreased bacterial richness and the frequency of preening behaviour in birds, known to regulate feather bacteria. Our results demonstrate for the first time the effects of common urban trace metals on plumage bacterial community and shed light on one of the mechanisms by which trace metals can affect bird fitness. Further studies are now needed to investigate how this effect modulates avian life history traits known to depend on plumage bacterial community.

Data from: Increased transgenerational epigenetic variation, but not predictable epigenetic variants, after environmental exposure in two apomictic dandelion lineages

DNA methylation is one of the mechanisms underlying epigenetic modifications. DNA methylations can be environmentally induced and such induced modifications can at times be transmitted to successive generations. However, it remains speculative how common such environmentally induced transgenerational DNA methylation changes are and if they persist for more than one offspring generation. We exposed multiple accessions of two different apomictic dandelion lineages of the Taraxacum officinale group (Taraxacum alatum and T. hemicyclum) to drought and salicylic acid (SA) treatment. Using methylation-sensitive amplified fragment length polymorphism markers (MS-AFLPs) we screened anonymous methylation changes at CCGG restriction sites throughout the genome after stress treatments and assessed the heritability of induced changes for two subsequent unexposed offspring generations. Irrespective of the initial stress treatment, a clear buildup of heritable DNA methylation variation was observed across three generations, indicating a considerable background rate of heritable epimutations. Less evidence was detected for environmental effects. Drought stress showed some evidence for accession-specific methylation changes, but only in the exposed generation and not in their offspring. By contrast, SA treatment caused an increased rate of methylation change in offspring of treated plants. These changes were seemingly undirected resulting in increased transgenerational epigenetic variation between offspring individuals, but not in predictable epigenetic variants. While the functional consequences of these MS-AFLP-detected DNA methylation changes remain to be demonstrated, our study shows that (1) stress-induced transgenerational DNA methylation modification in dandelions is genotype and context-specific; and (2) inherited environmental DNA methylation effects are mostly undirected and not targeted to specific loci.

opencc-zeroDec 2019View details →

Data from: Aircraft sound exposure leads to song frequency decline and elevated aggression in wild chiffchaffs

Abstract: 1. The ubiquitous anthropogenic low-frequency noise impedes communication by masking animal signals. To overcome this communication barrier, animals may increase the frequency, amplitude and delivery rate of their acoustic signals, making them more easily heard. However, a direct impact of intermittent, high-level aircraft noise on birds' behaviour living close to a runway has not been studies in detail. 2. We recorded common chiffchaffs Phylloscopus collybita songs near two airports and nearby control areas, and we measured sound levels in their territories at Manchester airport. The song recordings were made in between aircraft movements, when ambient sound levels were similar between airport and control populations. We also conducted playback experiments at the airport and a control population to test the salience of airport, and control population specific songs. 3. In contrast to the general pattern of increased song frequency in noisy areas, we show that common chiffchaffs at airports show a negative relationship between noise exposure level and song frequency. 4. Experimental data show that chiffchaffs living near airports also respond more aggressively to song playback. 5. Since the decrease in song frequency results in increased overlap with aircraft noise, these findings cannot be explained as an adaptation to improve communication. The increased levels of aggression suggests that chiffchaffs, like humans, might be affected behaviourally by extreme noise pollution. These findings should influence environmental impact assessments for airport expansions globally.

opencc-zeroNov 2019View details →

The role of non-glandular emergences in Croton floribundus (Euphorbiaceae) upon elevated ozone exposures

The role of non-glandular emergences in avoiding ozone (O3) damages by preventing its entrance into leaf tissues was previously suggested to the O3-tolerant species Croton floribundus (Euphorbiaceae). However, this function against O3 damage has been underestimated due to the covering wax layer mostly composed of saturated hydrocarbon with low reactivity to this gas. To evaluate the role of these structures in conferring tolerance to O3, we mechanically removed the non-glandular emergences from leaf blades of C. floribundus, submitted the plants to acute O3 fumigation, and assessed the morphological and microscopic alterations. Plants with intact leaves showed the same phenotype of control samples but showed microscopic markers of accelerated senescence. These alterations indicated a whole-plant response to O3. Plants bearing leaves with emergences removed exhibited specific morphological symptoms and microscopic markers of O3. The leaf emergences encompass a barrier for volatiles contention, preventing O3 damage to leaf tissues of C. floribundus. The absence of these structures possibly disperses defense volatiles quickly and allows this species to become vulnerable to O3 effects. This study highlights the relevance of surface structures in confer resistance of plants against O3 damages over biochemical defenses alone.

opencc-zeroDec 2018View details →

Data from: Risks of 23 specific malformations associated with prenatal exposure to ten antiepileptic drugs

Objective: To assess the association between exposure to monotherapy with 10 different antiepileptic drugs (AED) during the first two months of pregnancy and the risk of 23 major congenital malformations (MCMs). Methods: This nationwide cohort study, based on the French healthcare databases, included all pregnancies&[ge]20 weeks and ending between January 2011 and March 2015. Women were considered to be exposed when an AED had been dispensed between one month before and two months after the beginning of pregnancy. The reference group included pregnant women with no reimbursement for AEDs. MCMs were detected up to 12 months after birth (24 months for microcephaly, hypospadias and epispadias). Odds ratios were adjusted for potential confounders for MCMs with at least five cases. Otherwise, we calculated crude ORs with exact confidence intervals. Results: The cohort included 1,886,825 pregnancies, 2,997 of which were exposed to lamotrigine, 1,671 to pregabalin, 980 to clonazepam, 913 to valproic acid, 579 to levetiracetam, 517 to topiramate, 512 to carbamazepine, 365 to gabapentin, 139 to oxcarbazepine and 80 to phenobarbital. Exposure to valproic acid was associated with 8 specific types of MCMs (e.g. spina bifida, OR=19.4[8.6-43.5]) and exposure to topiramate was associated with an increased risk of cleft lip (6.8[1.4-20.0]). We identified three other signals. We found no significant association for lamotrigine, levetiracetam, carbamazepine, oxcarbazepine and gabapentin. Conclusions: These results confirm the teratogenicity of valproic acid and topiramate. Because of the small numbers of cases and possible confounding, the other three signals should be interpreted with appropriate caution.

Data from: Reproductive and behavior dysfunction induced by maternal androgen exposure and obesity is likely not gut microbiome-mediated

Polycystic ovary syndrome (PCOS) is a common endocrine and metabolic disorder of unclear etiology in women and is characterized by androgen excess, insulin resistance, and mood disorders. The gut microbiome is known to influence conditions closely related with PCOS, and several recent studies have observed changes in the stool microbiome of women with PCOS. The mechanism by which the gut microbiome interacts with PCOS is still unknown. We used a mouse model to investigate if diet-induced maternal obesity and maternal dihydrotestosterone (DHT) exposure, mimicking the lean and obese PCOS women, cause lasting changes in the gut microbiome of offspring. Fecal microbiome profiles were assessed using Illumina paired-end sequencing of 16S rRNA gene V4 amplicons. We found sex-specific effects of maternal and offspring diet, and maternal DHT exposure on fecal bacterial richness and taxonomic composition. Female offspring exposed to maternal obesity and DHT displayed reproductive dysfunction and anxiety-like behavior. Fecal microbiota transplantation from DHT and diet-induced obesity exposed female offspring to wild-type mice did not transfer reproductive dysfunction and did not cause the expected increase in anxiety-like behavior in recipients. Maternal obesity and androgen exposure affect the gut microbiome of offspring, but the disrupted estrous cycles and anxiety-like behavior are likely not microbiome-mediated.

opencc-zeroOct 2019View details →

Data from: Light-at-night exposure affects brain development through pineal allopregnanolone-dependent mechanisms

The molecular mechanisms by which environmental light conditions affect cerebellar development are incompletely understood. We showed that circadian disruption by light-at-night induced Purkinje cell death through pineal allopregnanolone (ALLO) activity during early life in chicks. Light-at-night caused the loss of diurnal variation of pineal ALLO synthesis during early life and led to cerebellar Purkinje cell death, which was suppressed by a daily injection of ALLO. The loss of diurnal variation of pineal ALLO synthesis induced not only reduction in pituitary adenylate cyclase-activating polypeptide (PACAP), a neuroprotective hormone, but also transcriptional repression of the cerebellar Adcyap1 gene that produces PACAP, with subsequent Purkinje cell death. Taken together, pineal ALLO mediated the effect of light on early cerebellar development in chicks.

opencc-zeroDec 2014View details →

Data from: Sperm whales reduce foraging effort during exposure to 1-2 kHz sonar and killer whale sounds

The time and energetic costs of behavioral responses to incidental and experimental sonar exposures, as well as control stimuli, were quantified using hidden state analysis of time series of acoustic and movement data recorded by tags (DTAG) attached to 12 sperm whales (Physeter macrocephalus) using suction cups. Behavioral state transition modeling showed that tagged whales switched to a non-foraging, non-resting state during both experimental transmissions of low-frequency active sonar from an approaching vessel (LFAS; 1–2 kHz, source level 214 dB re 1 μPa m, four tag records) and playbacks of potential predator (killer whale, Orcinus orca) sounds broadcast at naturally occurring sound levels as a positive control from a drifting boat (five tag records). Time spent in foraging states and the probability of prey capture attempts were reduced during these two types of exposures with little change in overall locomotion activity, suggesting an effect on energy intake with no immediate compensation. Whales switched to the active non-foraging state over received sound pressure levels of 131–165 dB re 1 μPa during LFAS exposure. In contrast, no changes in foraging behavior were detected in response to experimental negative controls (no-sonar ship approach or noise control playback) or to experimental medium-frequency active sonar exposures (MFAS; 6–7 kHz, source level 199 re 1 μPa m, received sound pressure level [SPL] = 73–158 dB re 1 μPa). Similarly, there was no reduction in foraging effort for three whales exposed to incidental, unidentified 4.7–5.1 kHz sonar signals received at lower levels (SPL = 89–133 dB re 1 μPa). These results demonstrate that similar to predation risk, exposure to sonar can affect functional behaviors, and indicate that increased perception of risk with higher source level or lower frequency may modulate how sperm whales respond to anthropogenic sound.

opencc-zeroOct 2019View details →

Data from: Proximity to roads, but not exposure to metal pollution, is associated with accelerated developmental telomere shortening in nestling great tits

Comprehensively understanding the factors affecting physiology and fitness in urban wildlife requires concurrently considering multiple stressors. To this end, we simultaneously assessed how metal pollution and proximity to roads affect body condition and telomere shortening between days 8 and 15 of age in nestling great tits (Parus major), a common urban bird. We employed a repeated-measures sampling design to compare telomere shortening and body condition between nestlings from four urban study sites south of Antwerp, Belgium, which are located at different distances from a metal pollution point source. In addition, we explored associations between metal exposure and telomere dynamics on the individual level by measuring blood concentrations of five metals/metalloids, of which lead, copper and zinc were present at concentrations about the limit of detection. To assess whether roadway-associated stressors (e.g. noise and air pollution) might affect nestling condition and telomere shortening, we measured the proximity of nest boxes to roads. Metal exposure was not associated with nestling telomere length or body condition, despite elevated blood lead concentrations close to a metal pollution source (mean ± SE = 0.270 ± 0.095 µg/g wet weight at the most polluted study site), suggesting that nestlings may have some capacity to detoxify metals. However, nestlings from nest boxes near roads exhibited more telomere shortening between days 8 and 15 of age, and shorter telomeres at day 15. Nestlings in poorer condition also had shorter telomeres, but proximity to the road was unrelated to body condition. Thus, nutritional stress is unlikely to mediate the relationship between proximity to roads and telomere length. Rather, proximity to roads could have affected telomere shortening by exposing nestlings to air or noise pollution. Our study highlights that traffic-related pollution, which is implicated in human health problems, might also affect urban wildlife.

opencc-zeroDec 2014View details →

Data from: Mercury exposure, stress and prolactin secretion in an Arctic seabird: an experimental study

Life-history theory predicts that long-lived organisms should reduce parental effort under inclement environmental conditions in order to favour long-term survival. Seabirds are long-lived top predators often exposed to environmental endocrine disrupting chemicals such as mercury (Hg). Hg-contaminated birds show disrupted parental behaviour. Avian parental behaviour is governed by two key hormones in birds: corticosterone (CORT, a glucocorticoid hormone) and prolactin (PRL, a pituitary hormone involved in parental care). Any disruption of these hormones may alter the ability of an individual to adjust parental behaviour to environmental conditions. The first aim of this study was to describe the relationships between blood Hg concentrations, plasma PRL and reproductive performance in Arctic black-legged kittiwakes (Rissa tridactyla). We a found negative relationship between plasma initial PRL and blood Hg concentrations in males. Moreover, Hg concentration was negatively related to breeding success in chick-rearing males. Secondly, to study the effect of a chronic increase in CORT levels on the Hg–PRL relationship, we experimentally increased stress with CORT pellet implantation. We predicted that Hg and CORT would act synergistically on PRL and an increase in CORT concentration would steepen the Hg–PRL relationship. However, adding CORT did not steepen the Hg–PRL relationship. Hatching success was significantly lower in CORT-implanted males than in controls, and breeding success was not reduced in CORT-implanted male kittiwakes with high levels of blood Hg. Our results suggest that Hg may impair reproductive performance through a disruption of PRL secretion. Contrary to our prediction, Hg and CORT did not act synergistically and the underlying mechanisms associating CORT and Hg with PRL might be more complex than a single interaction between two factors.

Data from: Association of in utero persistent organic pollutant exposure with placental thyroid hormones

In utero exposure to persistent organic pollutants (POPs) can result in thyroid function disorder, leading to concerns about their impact on fetal and neonatal development. The present study was performed to investigate the associations between placental levels of various POPs and thyroid hormones (THs). In a prospective Danish study initially established for assessing congenital cryptorchidism, 58 placenta samples were collected from mothers of boys born with (28) and without (30) cryptorchidism. The concentrations of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), organotin chemicals (OTCs), organochlorine pesticides (OCPs), thyroxine (T4), 3,3',5-triiodothyronine (T3), and 3,3',5'-triiodothyronine (rT3) were measured. The associations between placental THs and various POPs were analyzed using multiple linear regression. Five PBDEs, 35 PCBs, 14 PCDD/Fs, 3 OTCs, 25 OCPs, T4, T3, and rT3 were measured. No correlation between THs and the odds of cryptorchidism was found. Several POPs were significantly associated with THs: a) T4 was inversely associated with BDEs 99, 100, ΣPBDE, and 2378-TeCDD, and positively associated with 1234678-HpCDF; b) T3 was positively associated with 2378-TeCDF and 12378-PeCDF; c) rT3 was positively associated with PCB 81, 12378-PeCDF and 234678-HxCDF, and inversely associated with tributyltin (TBT), ΣOTC, and methoxychlor (MOC). These results revealed that POP exposures were associated with TH levels in placenta, a possible mechanism for the impacts of POP exposures on children's growth and development. This study provides new insight into the complexity of thyroid-disrupting properties of POPs. More research is needed to elucidate the biological consequences of POP exposures.

opencc-zeroDec 2015View details →

Data from: Integrating the pace-of-life syndrome across species, sexes and individuals: covariation of life history and personality under pesticide exposure

The pace-of-life syndrome (POLS) hypothesis integrates covariation of life-history traits along a fast–slow continuum and covariation of behavioural traits along a proactive–reactive personality continuum. Few studies have investigated these predicted life-history/personality associations among species and between sexes. Furthermore, whether and how contaminants interfere with POLS patterns remains unexplored. We tested for covariation patterns in life history and in behaviour, and for life-history/personality covariation among species, among individuals within species and between sexes. Moreover, we investigated whether pesticide exposure affects covariation between life history and behaviour and whether species and sexes with a faster POLS strategy have a higher sensitivity to pesticides. We reared larvae of four species of Ischnura damselflies in a common garden experiment with an insecticide treatment (chlorpyrifos absent/present) in the final instar. We measured four life-history traits (larval growth rate during the pesticide treatment, larval development time, adult mass and life span) and two behavioural traits (larval feeding activity and boldness, each before and after the pesticide treatment). At the individual level, life-history traits and behavioural traits aligned along a fast–slow and a proactive–reactive continuum, respectively. Species-specific differences in life history, with fast-lived species having a faster larval growth and development, a lower mass at emergence and a shorter life span, suggested that time constraints in the larval stage were predictably driving life-history evolution both in the larval stage and across metamorphosis in the adult stage. Across species, females were consistently more slow-lived than males, reflecting that a large body size and a long life span are generally more important for females. In contrast to the POLS hypothesis, there was only little evidence for the expected positive coupling between life-history pace and proactivity. Pesticide exposure decreased larval growth rate and affected life-history/personality covariation in the most fast-lived species. Our study supports the existence of life-history and behavioural continua with limited support for life-history/personality covariation. Variation in digestive physiology may explain this decoupling of life history and behaviour and provide valuable mechanistic insights to understand and predict the occurrence of life-history/personality covariation patterns.

openother-openJul 2015View details →

Heat Stress Exposure Maps - Base Scenario 1986 - 2005: Berlin, Germany (Map-1)

Heat Stress Exposure Maps - Base Scenario 1986 - 2005: Berlin, Germany Map-1 (zip.file) ref. to DOI: 10.5281/zenodo.45015

opencc-zeroApr 2016View details →

Exposure to high endotoxin concentration increases wheezing prevalence among laboratory animal workers: a cross-sectional study

Background: Endotoxin from Gram-negative bacteria are found in different concentrations in dust and on the ground of laboratories dealing with small animals and animal houses. Methods: Cross-sectional study performed in workplaces of two universities. Dust samples were collected from laboratories and animal facilities housing rats, mice, guinea pigs, rabbits or hamsters and analyzed by the “Limulus amebocyte lysate” (LAL) method. We also sampled workplaces without animals. The concentrations of endotoxin detected in the workplaces were tested for association with wheezing in the last 12 months, asthma defined by self-reported diagnosis and asthma confirmed by bronchial hyperresponsiveness (BHR) to mannitol. Results: Dust samples were obtained at 145 workplaces, 92 with exposure to animals and 53 with no exposure. Exposed group comprised 412 subjects and non-exposed group comprised 339 subjects. Animal-exposed workplaces had higher concentrations of endotoxin, median of 34.2 endotoxin units (EU) per mg of dust (interquartile range, 12.6-65.4), as compared to the non-exposed group, median of 10.2 EU/mg of dust (interquartile range, 2.6-22.2) (p < 0.001). The high concentration of endotoxin (above median, 20.4 EU/mg) was associated with increased wheezing prevalence (p < 0.001), i.e. 61% of workers exposed to high endotoxin concentration reported wheezing in the last 12 months compared to 29% of workers exposed to low endotoxin concentration. The concentration of endotoxin was not associated with asthma report or with BHR confirmed asthma. Conclusion: Exposure to endotoxin is associated with a higher prevalence of wheezing, but not with asthma as defined by the mannitol bronchial challenge test or by self-reported asthma. Preventive measures are necessary for these workers.

opencc-by-4.0Sep 2024View details →

Data and code for "Nutrient storage links past thermal exposure to current performance in phytoplankton"

Open the record for dataset details and reuse information.

opencc-by-4.0Dec 2015View details →

Potential impacts of future warming and land use changes on intra-urban heat exposure in Houston Texas

Extreme heat events in the United States are projected to become more frequent and intense as a result of climate change. We investigated the individual and combined effects of land use and warming on the spatial and temporal distribution of daily minimum temperature (Tmin) and daily maximum heat index (HImax) during summer in Houston, Texas. Present-day (2010) and near-future (2040) parcel-level land use scenarios were embedded within 1-km resolution land surface model (LSM) simulations. For each land use scenario, LSM simulations were conducted for climatic scenarios representative of both the present-day and near-future periods. LSM simulations assuming present-day climate but 2040 land use patterns led to spatially heterogeneous temperature changes characterized by warmer conditions over most areas, with summer average increases of up to 1.5°C (Tmin) and 7.3°C (HImax) in some newly developed suburban areas compared to simulations using 2010 land use patterns. LSM simulations assuming present-day land use but a 1°C temperature increase above the urban canopy (consistent with warming projections for 2040) yielded more spatially homogeneous metropolitan-wide average increases of about 1°C (Tmin) and 2.5°C (HImax), respectively. LSM simulations assuming both land use and warming for 2040 led to summer average increases of up to 2.5°C (Tmin) and 8.3°C (HImax), with the largest increases in areas projected to be converted to residential, industrial and mixed-use types. Our results suggest that urbanization and climate change may significantly increase the average number of summer days that exceed current threshold temperatures for initiating a heat advisory for metropolitan Houston, potentially increasing population exposure to extreme heat.

opennotspecifiedNov 2016View details →

Figure 2 in The fate of the TARDIS offspring: no intergenerational effects of space exposure

Figure 2. Schematic description of the different generations of Milnesium tardigradum referred to in this study.