Free-living Populations Research Articles

Trophic niches reflect compositional differences in microbiota among Caribbean sea urchins.

Sea urchins play a critical role in marine ecosystems, as they actively participate in maintaining the balance between coral and algae. We performed the first in-depth survey of the microbiota associated with four free-living populations of Caribbean sea urchins: Lytechinus variegatus, Echinometra lucunter, Tripneustes ventricosus, and Diadema antillarum. We compared the influence of the collection site, echinoid species and trophic niche to the composition of the microbiota. This dataset provides a comprehensive overview to date, of the bacterial communities and their ecological relevance associated with sea urchins in their natural environments. A total of sixty-samples, including surrounding reef water and seagrass leaves underwent 16S rRNA gene sequencing (V4 region) and high-quality reads were analyzed with standard bioinformatic approaches. While water and seagrass were dominated by Cyanobacteria such as Prochlorococcus and Rivularia respectively, echinoid gut samples had dominant Bacteroidetes, Proteobacteria and Fusobacteria. Propionigenium was dominant across all species’ guts, revealing a host-associated composition likely responsive to the digestive process of the animals. Beta-diversity analyses showed significant differences in community composition among the three collection sites, animal species, and trophic niches. Alpha diversity was significantly higher among L. variegatus samples compared to the other species. L. variegatus also displayed an increased abundance of Planctomycetes and Cyanobacterial OTUs. The bacterial community of this herbivorous echinoid reflected similarities to the microfilm community found on Thalassia testudinum leaves; a very abundant seagrass and its main food resource. The results of this study elaborate on the microbial ecology of four important Caribbean echinoids, confirming that selection on the microbial community is trophic-niche dependent.

The Influence of Biological Factors on Haematological Values in Wild Marsh Harrier (Circus aeruginosus) Nestlings.

Simple SummaryHaematological examination can be used to address the health state of birds. The present study aimed to investigate how hatching order, brood size, and nest initiation date influence the haemoglobin level, red blood cell count, white blood cell count, and glucose level in the blood of raptor nestlings in which brood reduction occurs during nestling rearing. Blood samples were collected to assess the health status of wild marsh harrier nestlings in the agricultural landscape of eastern Poland. Statistical analyses revealed that hatching order, but not brood size or nest initiation date, had an impact on the haematological data of nestlings. Hatching order affected these data in that haemoglobin levels and red blood cell counts gradually decreased, whereas glucose levels and white blood cell counts increased, from the first- to the last-hatched nestlings. The poor condition of the youngest nestlings reflected in these indices may increase the likelihood of their perishing, and consequently, of brood reduction.Marsh harrier (Circus aeruginosus) is a species with obligatory cainism, in which hatching asynchrony creates a pronounced size hierarchy in nestlings. The size-related competitive advantage of older nestlings means that they tend to dominate the younger ones, and brood reduction occurs in most nests. The aim of the study was to reference values and carry out a haematological examination in order to evaluate the physiological status and health of nestlings with respect to hatching order, brood size, and nest initiation date. To do so, we examined 19 nests with a total of 58 nestlings from a free-living population of this species located in fishpond complexes in the agricultural landscape of eastern Poland. Repeated blood samples (118 in all) were collected from nestlings. The following parameters were measured using fresh full blood: red blood cell count (RBC), haemoglobin level (Hb), white blood cell count (WBC), and plasma glucose level (Glu). The data were analysed using generalized linear mixed models and linear mixed models ((G)LMM). The study revealed that hatching order, but not brood size or nest initiation date, affected the physical condition of marsh harrier nestlings. Hb levels and RBC counts gradually decreased, whereas Glu levels and WBC counts increased from the first- to the last-hatched nestlings. This result points to the generally poorer condition of the youngest nestlings compared with their older siblings. The poor physiological condition of the youngest nestlings may consequently increase the likelihood of their perishing, and hence, of brood reduction.

Associations between air pollution and depressive symptoms in older adults: a repeated measurement study

BACKGROUND AND AIM: Epidemiological studies concerning the relationships between different exposure windows of air pollution and symptoms of depression in older adults are limited. Hence, we investigate the relations between short-term and long-term exposure to ambient air pollution (PM10, O3, SO2, CO, and NOX) and depressive symptoms in a community-dwelling, free-living elderly population. METHODS: Study participants were in a multiple-wave representative sample (Taiwan Longitudinal Study on Aging, n=1956). In four surveys between 1996 and 2007, their depressive symptoms were assessed using the 10-itemed Center for Epidemiologic Studies Depression (CESD-10). We estimated air pollution from 1993 to 2007, including daily concentrations of five air pollutants from air quality monitoring stations, based on the administration zone of each participant’s residence. Generalized linear mixed models were applied to examine these associations after adjusting for covariates at different exposure windows (7-, 14-, 21-, 30-, 60-, 90-, 180-days, and 1-year moving averages). RESULTS:In one-pollutant model, the short-term and long-term exposure to CO and NOX were associated with increased risk of depressive symptoms; the ORs and 95% CIs for each 1 ppm increment in CO at 7-, 14-, 21-, 30-, 60-, 90-, 180-days, and 1-year moving averages were 2.23 (1.53, 3.27), 2.27 (1.63, 3.16), 2.19 (1.62, 2.96), 2.23 (1.62, 3.07), 2.12 (1.55, 2.90), 2.15 (1.55, 2.98), 2.14 (1.53, 2.99), 2.13 (1.56, 2.91), respectively. Moreover, for each 10 ppb increment in NOX at series exposure windows were 1.16 (1.08, 1.25), 1.18 (1.11, 1.26), 1.17 (1.11, 1.24), 1.18 (1.11, 1.25), 1.18 (1.11, 1.26), 1.18 (1.11, 1.26), 1.18 (1.11, 1.26), 1.18 (1.11, 1.26), respectively. In two-pollutant model, only the associations of exposure to NOX with depressive symptoms remained robust after adjustment for any other pollutant. CONCLUSIONS:Exposure to traffic-related air pollutants could increase the risk for depressive symptoms in older adults. KEYWORDS: air pollution, depressive symptoms, older adults, repeated measurement.

Natural variation in yolk fatty acids, but not androgens, predicts offspring fitness in a wild bird

BackgroundIn egg-laying animals, mothers can influence the developmental environment and thus the phenotype of their offspring by secreting various substances into the egg yolk. In birds, recent studies have demonstrated that different yolk substances can interactively affect offspring phenotype, but the implications of such effects for offspring fitness and phenotype in natural populations have remained unclear. We measured natural variation in the content of 31 yolk components known to shape offspring phenotypes including steroid hormones, antioxidants and fatty acids in eggs of free-living great tits (Parus major) during two breeding seasons. We tested for relationships between yolk component groupings and offspring fitness and phenotypes.ResultsVariation in hatchling and fledgling numbers was primarily explained by yolk fatty acids (including saturated, mono- and polyunsaturated fatty acids) - but not by androgen hormones and carotenoids, components previously considered to be major determinants of offspring phenotype. Fatty acids were also better predictors of variation in nestling oxidative status and size than androgens and carotenoids.ConclusionsOur results suggest that fatty acids are important yolk substances that contribute to shaping offspring fitness and phenotype in free-living populations. Since polyunsaturated fatty acids cannot be produced de novo by the mother, but have to be obtained from the diet, these findings highlight potential mechanisms (e.g., weather, habitat quality, foraging ability) through which environmental variation may shape maternal effects and consequences for offspring. Our study represents an important first step towards unraveling interactive effects of multiple yolk substances on offspring fitness and phenotypes in free-living populations. It provides the basis for future experiments that will establish the pathways by which yolk components, singly and/or interactively, mediate maternal effects in natural populations.

Dietary fructose intake is correlated with fat distribution in the Newfoundland population

Objective: Increased dietary fructose intake is associated with elevated body weight and body mass index. Few studies are available regarding the relationship between fat distribution and dietary fructose intake. The aim of this study was to investigate the association between dietary fructose intake and fat distribution in adults in a large Newfoundland cohort.Methods: We analyzed 2298 adults from CODING (Complex Diseases in the New found land Population: Environment and Genetics) study. Intake of dietary fructose was evaluated from the Willett food frequency questionnaire. Fat distribution was estimated by dual-energy x-ray absorptiometry. Partial correlation analysis was used to determine the correlations of dietary fructose intake with fat distribution adjusted for major confounding factors.Results: Daily dietary fructose intake was negatively associated with arm fat in postmenopausal women (r = –0.080, P < 0.05), but positively associated with arm fat in premenopausal women after adjusting for age, total calorie intake, and physical activity levels (r = 0.079, P < 0.05). Dietary fructose intake was negatively correlated with both arm fat (r = –0.131, P < 0.05) and visceral fat (r = –0.124 measured in mass, r = –0.124 measured in volume respectively; P < 0.05) in men <45 y of age, not in men ≥45 y.Conclusion: This study demonstrated that dietary fructose intake is significantly correlated with arm fat in both women and men, and visceral fat in men in the Newfoundland free-living population. The correlations are sex- and menopause-status dependent.

The 3-Year Effect of the Mediterranean Diet Intervention on Inflammatory Biomarkers Related to Cardiovascular Disease.

The intervention with the Mediterranean diet (MD) pattern has evidenced short-term anti-inflammatory effects, but little is known about its long-term anti-inflammatory properties at molecular level. This study aims to investigate the 3-year effect of MD interventions compared to low-fat diet (LFD) on changes on inflammatory biomarkers related to atherosclerosis in a free-living population with a high-risk of cardiovascular disease (CD). Participants (n = 285) in the PREDIMED trial were randomly assigned into three intervention groups: MD with extra-virgin olive oil (EVOO) or MD-Nuts, and a LFD. Fourteen plasma inflammatory biomarkers were determined by Luminex assays. An additional pilot study of gene expression (GE) was determined by RT-PCR in 35 participants. After 3 years, both MDs showed a significant reduction in the plasma levels of IL-1β, IL-6, IL-8, TNF-α, IFN-γ, hs-CRP, MCP-1, MIP-1β, RANTES, and ENA78 (p < 0.05; all). The decreased levels of IL-1β, IL-6, IL-8, and TNF-α after MD significantly differed from those in the LFD (p < 0.05). No significant changes were observed at the gene level after MD interventions, however, the GE of CXCR2 and CXCR3 tended to increase in the control LFD group (p = 0.09). This study supports the implementation of MD as a healthy long-term dietary pattern in the prevention of CD in populations at high cardiovascular risk.

Population genetics, invasion pathways and public health risks of the raccoon and its roundworm Baylisascaris procyonis in northwestern Europe.

The geographic range of the zoonotic raccoon roundworm (Baylisascaris procyonis) is expanding together with the range of its host, the raccoon (Procyon lotor). This creates a new public health risk in parts of Europe where this parasite was previously absent. In the Netherlands, a raccoon population is becoming established and incidental findings of B. procyonis have been reported. To assess the risk to public health, the prevalence of B. procyonis was determined in the province of Limburg, where currently the largest Dutch raccoon population is present, as well as in the adjoining region of southern Belgium. Furthermore, genetic methods were employed to assess invasion pathways of both the raccoon and B. procyonis to aid in the development of control measures. Macroscopic analysis of intestinal content and testing of faecal samples were performed to detect B. procyonis adults and eggs. The population genetics of both B. procyonis and its raccoon host were analysed using samples from central and northwestern Europe. B. procyonis was found in 14/23 (61%, 95% CI: 41%-78%) raccoons from Limburg, but was not detected in 50 Belgian raccoons. Genetic analyses showed that the majority of the Dutch raccoons and their roundworms were introduced through ex-captive individuals. As long as free-living raccoon populations originate from captivity, population control methods may be pursued. However, natural dispersal from the border regions will complicate prolonged population control. To reduce the public health risk posed by B. procyonis, public education to increase awareness and adapt behaviour towards raccoons is key.

Evolutionary Relationships of Ljungan Virus Variants Circulating in Multi-Host Systems across Europe.

The picornavirus named ‘Ljungan virus’ (LV, species Parechovirus B) has been detected in a dozen small mammal species from across Europe, but detailed information on its genetic diversity and host specificity is lacking. Here, we analyze the evolutionary relationships of LV variants circulating in free-living mammal populations by comparing the phylogenetics of the VP1 region (encoding the capsid protein and associated with LV serotype) and the 3Dpol region (encoding the RNA polymerase) from 24 LV RNA-positive animals and a fragment of the 5′ untranslated region (UTR) sequence (used for defining strains) in sympatric small mammals. We define three new VP1 genotypes: two in bank voles (Myodes glareolus) (genotype 8 from Finland, Sweden, France, and Italy, and genotype 9 from France and Italy) and one in field voles (Microtus arvalis) (genotype 7 from Finland). There are several other indications that LV variants are host-specific, at least in parts of their range. Our results suggest that LV evolution is rapid, ongoing and affected by genetic drift, purifying selection, spillover and host evolutionary history. Although recent studies suggest that LV does not have zoonotic potential, its widespread geographical and host distribution in natural populations of well-characterized small mammals could make it useful as a model for studying RNA virus evolution and transmission.

Evaluating the Robustness of Biomarkers of Dairy Food Intake in a Free-Living Population Using Single- and Multi-Marker Approaches.

Studies examining associations between self-reported dairy intake and health are inconclusive, but biomarkers hold promise for elucidating such relationships by offering objective measures of dietary intake. Previous human intervention studies identified several biomarkers for dairy foods in blood and urine using non-targeted metabolomics. We evaluated the robustness of these biomarkers in a free-living cohort in the Netherlands using both single- and multi-marker approaches. Plasma and urine from 246 participants (54 ± 13 years) who completed a food frequency questionnaire were analyzed using liquid and gas chromatography-mass spectrometry. The targeted metabolite panel included 37 previously-identified candidate biomarkers of milk, cheese, and/or yoghurt consumption. Associations between biomarkers and energy-adjusted dairy food intakes were assessed by a ‘single-marker’ generalized linear model, and stepwise regression was used to select the best ‘multi-marker’ panel. Multi-marker models that also accounted for common covariates better captured the subtle differences for milk (urinary galactose, galactitol; sex, body mass index, age) and cheese (plasma pentadecanoic acid, isoleucine, glutamic acid) over single-marker models. No significant associations were observed for yogurt. Further examination of other facets of validity of these biomarkers may improve estimates of dairy food intake in conjunction with self-reported methods, and help reach a clearer consensus on their health impacts.

Particle-associated and free-living bacterial communities in an oligotrophic sea are affected by different environmental factors.

In the oceans and seas, environmental conditions change over multiple temporal and spatial scales. Here, we ask what factors affect the bacterial community structure across time, depth and size fraction during six seasonal cruises (2 years) in the ultra-oligotrophic Eastern Mediterranean Sea. The bacterial community varied most between size fractions (free-living (FL) vs. particle-associated), followed by depth and finally season. The FL community was taxonomically richer and more stable than the particle-associated (PA) one, which was characterized by recurrent 'blooms' of heterotrophic bacteria such as Alteromonas and Ralstonia. The heterotrophic FL and PA communities were also correlated with different environmental parameters: the FL population correlated with depth and phytoplankton, whereas PA bacteria were correlated primarily with the time of sampling. A significant part of the variability in community structure could, however, not be explained by the measured parameters. The metabolic potential of the PA community, predicted from 16S rRNA amplicon data using PICRUSt, was enriched in pathways associated with the degradation and utilization of biological macromolecules, as well as plastics, other petroleum products and herbicides. The FL community was enriched in predicted pathways for the metabolism of inositol phosphate, a potential phosphorus source, and of polycyclic aromatic hydrocarbons.

154-OR: People Who Get More Hours of Sleep Have Lower Mean Glucose: Analysis of Continuous Glucose Monitoring and Fitbit Data in a Free-Living Population without Diabetes

Background: Sleep disorders are associated with having or developing type 2 diabetes, increased insulin resistance, and higher BMI. The relationship between sleep duration and continuous glucose monitoring (CGM) metrics has not been well studied. We examined the relationship between CGM-based metrics and sleep duration in a population without diabetes. Methods: Glucose metrics from a 10-day blinded CGM (Dexcom G6) wear and sleep metrics from a concurrent unblinded Fitbit wear were collected. Participants (mean (SD) age= 49.1 (10) years, BMI= 29.5 (8) kg/m2, 90% female, 14% African American) were recruited from an employee health plan in the Southeastern US. Forty-nine individuals without diabetes or prediabetes were included in this analysis. A linear regression model adjusting for age and BMI was used to evaluate the relationship between mean daytime glucose and nightly hours of sleep. Results: Participants recorded a median (IQR) 6.4 (6.1, 7.1) nightly hours of sleep, 6416 (5112, 8071) daily steps, and 12.7 (12.1, 13.5) daily sedentary hours. Mean (SD) mean daytime glucose was 112.7 (11.5) mg/dL and coefficient of variation was 15.4 (3) %. Mean daytime glucose was significantly and inversely associated with nightly hours of sleep (Beta= -3.1, p &amp;lt;0.05). Conclusion: In this population without diabetes, each additional one hour of sleep was associated with 3.1 mg/dL lower mean daytime glucose. This finding aligns with existing research on the protective effects of sleep on glycemic health and suggests it may be beneficial for people at risk for developing diabetes to improve their sleep habits. Longitudinal research where behavioral data is collected along with CGM can provide further insights into correlates of developing prediabetes and type 2 diabetes. Disclosure M. A. Crawford: Employee; Self; Dexcom, Inc. S. K. Pickus: Employee; Self; Dexcom, Inc. K. C. Hames: Employee; Self; Dexcom, Inc. M. Johnson: Employee; Self; Dexcom, Inc. I. J. Klein: None. G. J. Norman: Employee; Self; Dexcom, Inc.

Predicting Malnutrition Risk with Data from Routinely Measured Clinical Biochemical Diagnostic Tests in Free-Living Older Populations.

Malnutrition (undernutrition) in older adults is often not diagnosed before its adverse consequences have occurred, despite the existence of established screening tools. As a potential method of early detection, we examined whether readily available and routinely measured clinical biochemical diagnostic test data could predict poor nutritional status. We combined 2008–2017 data of 1518 free-living individuals ≥50 years from the United Kingdom National Diet and Nutrition Survey (NDNS) and used logistic regression to determine associations between routine biochemical diagnostic test data, micronutrient deficiency biomarkers, and established malnutrition indicators (components of screening tools) in a three-step validation process. A prediction model was created to determine how effectively routine biochemical diagnostic tests and established malnutrition indicators predicted poor nutritional status (defined by ≥1 micronutrient deficiency in blood of vitamins B6, B12 and C; selenium; or zinc). Significant predictors of poor nutritional status were low concentrations of total cholesterol, haemoglobin, HbA1c, ferritin and vitamin D status, and high concentrations of C-reactive protein; except for HbA1c, these were also associated with established malnutrition indicators. Additional validation was provided by the significant association of established malnutrition indicators (low protein, fruit/vegetable and fluid intake) with biochemically defined poor nutritional status. The prediction model (including biochemical tests, established malnutrition indicators and covariates) showed an AUC of 0.79 (95% CI: 0.76–0.81), sensitivity of 66.0% and specificity of 78.1%. Clinical routine biochemical diagnostic test data have the potential to facilitate early detection of malnutrition risk in free-living older populations. However, further validation in different settings and against established malnutrition screening tools is warranted.

Improvement of sperm traits related to the high level of extra-pair fertilization in tree sparrow population under long-term environmental heavy metal pollution

Environmental stress can affect sperm traits whose changes have been reported to be associated with extra-pair fertilization (EPF) level in natural animal populations. However, little is known regarding how exposure to environmental heavy metals influences sperm traits and EPF level in free-living bird populations. In a previous study, we found that a tree sparrow (Passer montanus) population that has been exposed to heavy metal pollution over 60 years (Baiyin, BY) exhibits increased sperm quality compared with a population from a relatively unpolluted area (Liujiaxia, LJX). The high sperm quality could be related to extra-pair mating rates. Therefore, the present study investigated EPF level (the ratio of extra-pair offspring) in tree sparrow populations from BY and LJX, and analyzed the relationship between sperm traits (morphology, velocity and quantity) and EPF success. EPF success of tree sparrows was significantly correlated with their sperm velocity (p = 0.048) and total sperm length (p = 0.045), indicating that these sperm traits were important for EPF success. Tree sparrows from the BY population produced longer sperm with lower head/flagellum ratio and faster swimming sperm and showed a significantly higher EPF level than conspecifics from LJX. Thus, adaptive variation of sperm characteristics was related to the high EPF level in tree sparrows under long-term environmental heavy metal pollution. The findings are of scientific significance for exploring the evolution of mating tactics in wild bird populations under environmental stress.

Representations of Free-Living and Unrestrained Dogs as an Emerging Public Health Issue in Australian Newspapers

That dogs can live and breed as free-living animals contributes to public health risks including zoonotic transmission, dog bites, and compromising people’s sense of safety in public spaces. In Australia, free-living dog populations are comprised of domestic dogs, dingoes, and dog–dingo hybrids, and are described using various terms (for example, stray or community), depending on social or geographic context. Urban expansion and regional migration mean that risks associated with contact between humans and free-living dogs are increasing. Public health authorities, local governments, and community organisations have called for transdisciplinary partnerships to address dog-related health risks with a sustainable long-term approach. Values pluralism and a lack of sustained community engagement in affected areas have meant that the outcome of such efforts to date has been mixed. To identify ideas in public circulation about the impact of unrestrained and free-living dogs on human health and well-being, and understand the framework through which these animals are problematised and solutions are proposed in public discourse, we systematically examined coverage of these issues in print media. Our analyses indicate that reporting in Australian newspapers tends to frame the public health impacts of free-living dogs as problems of public order requiring direct government action to re-establish control. The public health impacts of free-living dog populations in Australia have complex causes that intersect at the nexus between human and canine behaviour, agricultural and land management practices, local bylaws, and efforts to conserve ecological systems. Placing responsibility on governments limits opportunities for greater community involvement in developing integrated One Health approaches. Better-quality evidence of the impacts of dog populations on community health and well-being, and broad community support are needed to reshape public debates on animal control, which, ultimately, will promote more effective approaches to mitigate dog-related public health risks at the human–animal–environment interface.

Patterns of MHC-dependent sexual selection in a free-living population of sheep.

The MHC is one of the most polymorphic gene clusters in vertebrates and play an essential role in adaptive immunity. Apart from pathogen-mediated selection, sexual selection can also contribute to the maintenance of MHC diversity. MHC-dependent sexual selection could occur via several mechanisms but at present there is no consensus as to which of these mechanisms are involved and their importance. Previous studies have often suffered from limited genetic and behavioural data and small sample size, and were rarely able to examine all the mechanisms together, determine whether signatures of MHC-based non-random mating are independent of genomic effects or differentiate whether MHC-dependent sexual selection takes place at the pre- or post-copulatory stage. In this study, we use Monte Carlo simulation to investigate evidence for non-random MHC-dependent mating patterns by all three mechanisms in a free-living population of Soay sheep. Using 1710 sheep diplotyped at the MHC class IIa region and genome-wide SNPs, together with field observations of consorts, we found sexual selection against a particular haplotype in males at the pre-copulatory stage and sexual selection against female MHC heterozygosity during the rut. We also found MHC-dependent disassortative mating at the post-copulatory stage, along with strong evidence of inbreeding avoidance at both stages. However, results from generalized linear mixed models suggest that the pattern of MHC-dependent disassortative mating could be a by-product of inbreeding avoidance. Our results therefore suggest that while multiple apparent mechanisms of non-random mating with respect to the MHC may occur, some of them have alternative explanations.

Deep-sea mussels from a hybrid zone on the Mid-Atlantic Ridge host genetically indistinguishable symbionts

The composition and diversity of animal microbiomes is shaped by a variety of factors, many of them interacting, such as host traits, the environment, and biogeography. Hybrid zones, in which the ranges of two host species meet and hybrids are found, provide natural experiments for determining the drivers of microbiome communities, but have not been well studied in marine environments. Here, we analysed the composition of the symbiont community in two deep-sea, Bathymodiolus mussel species along their known distribution range at hydrothermal vents on the Mid-Atlantic Ridge, with a focus on the hybrid zone where they interbreed. In-depth metagenomic analyses of the sulphur-oxidising symbionts of 30 mussels from the hybrid zone, at a resolution of single nucleotide polymorphism analyses of ~2500 orthologous genes, revealed that parental and hybrid mussels (F2–F4 generation) have genetically indistinguishable symbionts. While host genetics does not appear to affect symbiont composition in these mussels, redundancy analyses showed that geographic location of the mussels on the Mid-Atlantic Ridge explained most of the symbiont genetic variability compared to the other factors. We hypothesise that geographic structuring of the free-living symbiont population plays a major role in driving the composition of the microbiome in these deep-sea mussels.

Urinary neopterin of wild chimpanzees indicates that cell-mediated immune activity varies by age, sex, and female reproductive status

The study of free-living animal populations is necessary to understand life history trade-offs associated with immune investment. To investigate the role of life history strategies in shaping proinflammatory cell-mediated immune function, we analyzed age, sex, and reproductive status as predictors of urinary neopterin in 70 sexually mature chimpanzees (Pan troglodytes) at Ngogo, Kibale National Park, Uganda. In the absence of clinical signs of acute infectious disease, neopterin levels significantly increased with age in both male and female chimpanzees, as observed in humans and several other vertebrate species. Furthermore, males exhibited higher neopterin levels than females across adulthood. Finally, females with full sexual swellings, pregnant females, and post-reproductive females, the oldest individuals in our sample, exhibited higher neopterin levels than lactating females and cycling females without full swellings. Variation in females’ neopterin levels by reproductive status is consistent with post-ovulatory and pregnancy-related immune patterns documented in humans. Together, our results provide evidence of ample variation in chimpanzee immune activity corresponding to biodemographic and physiological variation. Future studies comparing immune activity across ecological conditions and social systems are essential for understanding the life histories of primates and other mammals.

A report on the Gubbio Study thirty-eight years after its inception.

The Gubbio Population Study (Gubbio Study) is a prospective epidemiological study carried out on the resident population of the city of Gubbio, Perugia, Italy. The study's objectives were both of public health nature (the control and awareness of hypertension), and experimental (the role of electrolyte handling at the cellular membrane level and its relation to hypertension). Additional objectives were addressed during the 30+ year activity of the study, in particular the role of kidney dysfunction. Three active screenings (exams) were performed beginning 38 years ago: the first (Exam 1) in 1983-1986 (5376 individuals - response rate 92%) and two follow-up exams, were completed between 1989-92 (Exam 2) and 2001-2007 (Exam 3). Data collected include demographics, personal and family medical history, lifestyle (smoking, alcohol, diet and physical activity), education, type of work, anthropometry, blood pressure, pulse rate, blood biochemistry, urine biochemistry and special investigations on cellular electrolyte handling. Additional measurements were performed in selected subgroups of participants. Data on hospitalizations, mortality and causes of death were collected after the completion of Exam 1. The main results of the study, presented in this paper, identify new variables to consider in screening for cardiovascular risk factors, and show the impact that the focused and coordinated effort of a longitudinal program can have on a free-living population'. The data are of relevance to Public Health and to experimental medicine alike and vouch to the importance of the control of risk factors at the community level.

CLINICAL PATHOLOGY OF CAPTIVE ENDANGERED MAHOGANY GLIDERS (PETAURUS GRACILIS) IN RESPONSE TO ENVIRONMENTAL CHANGE.

The impetus of this study was the imperative to establish blood biomarker values for clinically healthy mahogany gliders (Petaurus gracilis) in order to monitor the health status of eight captive individuals during their movement to a new facility. The study established ranges for 18 hematologic and 21 biochemical blood biomarkers for healthy individuals in a captive environment. The reported values are consistent with those published for other Australian glider and possum species. No statistically significant differences were found between the sexes, but significant age effects were observed. Specifically, subadult animals reported significantly higher total white cell counts, lymphocyte counts, alkaline phosphatase, creatine kinase, and glucose and chloride levels, compared to adult animals. Although there were no clinically significant changes in blood biomarkers associated with the relocation, many of the hematologic and biochemical biomarkers demonstrated the expected changes associated with the physiological stress of relocation. Specifically, triglycerides, glucose, globulins, creatinine kinase, aspartate transferase (AST), total protein, urea, phosphorous, potassium, sodium, chloride, neutrophils, and hematocrit showed changes with the large environmental change. The majority of the blood biomarkers returned to baseline levels 5 wk postrelocation, with all but one aged animal showing no signs of chronic health derangements following the relocation. The abnormal blood biomarker profiles of two geriatric individuals, one male diagnosed with pericloacal and adrenal gland tumors at the beginning of the study, and one female diagnosed with chronic urinary tract infections and suspected bone marrow disease following the relocation, are presented. The findings of this study inform the health monitoring of native gliders in captivity, rehabilitation, and clinical research scenarios. These findings also provide useful baseline data to aid in the health assessment of captive-bred individuals during their reintroduction into free-living populations.

Within-trio tests provide little support for post-copulatory selection on major histocompatibility complex haplotypes in a free-living population.

Sexual selection has been proposed as a force that could help maintain the diversity of major histocompatibility complex (MHC) genes in vertebrates. Potential selective mechanisms can be divided into pre-copulatory and post-copulatory, and in both cases, the evidence for occurrence is mixed, especially in natural populations. In this study, we used a large number of parent-offspring trios that were diplotyped for MHC class II genes in a wild population of Soay sheep (Ovis aries) to examine whether there was within-trio post-copulatory selection on MHC class II genes at both the haplotype and diplotype levels. We found there was transmission ratio distortion of one of the eight MHC class II haplotypes (E) which was transmitted less than expected by fathers, and transmission ratio distortion of another haplotype (A) which was transmitted more than expected by chance to male offspring. However, in both cases, these deviations were not significant after correction for multiple tests. In addition, we did not find any evidence of post-copulatory selection at the diplotype level. These results imply that, given known parents, there is no strong post-copulatory selection on MHC class II genes in this population.