Herpes viruses are responsible for a variety of pathological effects in humans and in both wild and domestic animals. One mechanism that has been proposed to facilitate replication and activity of herpes viruses is oxidative stress (OS). We used meta-analytical techniques to test the hypotheses that (1) herpes virus infection causes OS and (2) supplementation of antioxidants reduces virus load, indicating that replication is favoured by a state of OS. Results based on studies on mammals, including humans, and birds show that (1) OS is indeed increased by herpes virus infection across multiple tissues and species, (2) biomarkers of OS may change differently between tissues, and (3) the effect size does not differ among different virus strains. In addition, the increase of oxidative damage in blood (tissue commonly available in ecological studies) was similar to that in the tissues most sensitive to the herpes virus. Our results also show that administration of antioxidants reduces virus yield, indicating that a condition of OS is favorable for the viral replication. In addition, some antioxidants may be more efficient than others in reducing herpes virus yield. Our results point to a potential mechanism linking herpes virus infection to individual health status.

Sebastiano, M. et al. (2016) High levels of mercury and low levels of persistent organic pollutants in a tropical seabird in French Guiana, the Magnificent frigatebird, Fregata magnificens. Environmental Pollution, 214, pp. 384-393. (doi:10.1016Pollution, 214, pp. 384-393. (doi:10. /j.envpol.2016 This is the author's final accepted version.There may be differences between this version and the published version. You are advised to consult the publisher's version if you wish to cite from it.http://eprints.gla.ac.uk/121333/ In the present study, trace elements and persistent organic pollutants (POPs) were quantified 26 from Magnificent frigatebirds (Fregata magnificens) breeding at a southern Atlantic island. 27Stable isotope ratio of carbon (δ 13 C) and nitrogen (δ 15 N) were also measured to infer the role 28 of foraging habitat on the contamination. For another group from the same colony, GPS tracks 29 were recorded to identify potential foraging areas where the birds may get contaminated. Capsule abstract 50In the present study we found high levels of mercury and low levels of persistent organic 51 pollutants in a tropical seabird breeding in a protected area. 52 53

In this study, we examined the pathophysiological consequences likely to be attributable to a herpesvirus infection for immune function, corticosterone, telomere length and inflammation. We found that the plasma concentration of haptoglobin was strongly associated with the observable clinical manifestation of disease and could predict probabilities of survival.

AimNest building is widespread among animals. Nests may provide receptacles for eggs, developing offspring and the parents, and protect them from adverse environmental conditions. Nests may also indicate the quality of the territory and its owner and can be considered as an extended phenotype of its builder(s). Nests may, thus, function as a sexual and social signal. Here, we examined ecological and abiotic factors—temperature, nest predation and interspecific information utilization—shaping geographical variation in a specific nest structure—hair and feather cover of eggs—and its function as an extended phenotype before incubation in great (Parus major) and blue tits (Cyanistes caeruleus) across Europe. We also tested whether egg covering is associated with reproductive success of great tits.LocationFourteen different study sites and 28 populations across Europe.TaxonParus major, Cyanistes caeruleus.MethodsWe recorded clutch coverage estimates and collected egg covering nest material from the tit nests. We also measured nest specific breeding parameters and phenotypic measurements on adults. We tested whether mean spring temperatures, nest predation rates and flycatcher (Ficedula spp) densities in the study areas explain the large‐scale geographical variation of clutch coverage and reproductive success of tits.ResultsThe degree of egg coverage of great tits increased with lower mean spring temperature, higher nest predation rate and higher flycatcher density. We did not find egg covering of blue tits to be associated with any of the ecological or abiotic factors. Moreover, egg covering of great tits was not associated with reproductive success in our cross‐sectional data, yet a rigorous assessment of fitness effects would require long‐term data.Main conclusionsOur findings suggest that, in great tits, egg covering may simultaneously provide thermal insulation against cold temperatures during egg‐laying in spring and also represent a counter‐adaptation to reduce information parasitism by flycatchers and nest predation. Hence, geographical variation in interspecific interactions, and consequently in co‐evolutionary processes, may affect the evolution of nest characteristics besides environmental conditions.

Fernandez, et al.. Trophic ecology drives contaminant concentrations within a tropical seabird community. Environmental Pollution, Elsevier, 2017Elsevier, , 227, pp.183 -193. <10.1016Elsevier, /j.envpol.2017 Hg concentration in several adults Laughing gulls Leucophaeus atricilla and Royal ternsThalasseus maximus, and in all Magnificent frigatebirds was similar or higher than that of high contaminated seabird populations. Furthermore, nestling red blood cells also contained Hg concentrations of concern, and further studies should investigate its potential health impact in this seabird community. Differences in adult trophic ecology of the six species explained interspecific variation in exposure to trace element and POPs, while nestling trophic ecology provides indications about the diverse feeding strategies adopted by the six species, with the consequent variation in exposure to contaminants.

Environmental factors that can influence telomeres are diverse, but the association between telomeres and exposure to environmental contaminants is yet to be elucidated. To date, prior studies have focused on legacy persistent chlorinated pollutants (POPs), while the effects of poly- and perfluoroalkyl substances (PFAS) have been poorly documented. Here, we investigated the associations among PFAS congeners, absolute telomere length (cross-sectional approach), and telomere dynamics (rate of telomere length change over time, longitudinal approach) in one of the most contaminated arctic top predators, the glaucous gull Larus hyperboreus from Svalbard. We further estimated the effect of PFAS on apparent survival rates and re-sighting probabilities using a 10-year capture/recapture dataset (2010–2019). We found that birds exposed to higher concentrations of perfluorononadecanoate (PFNA) (median of 1565 pg/mL of ww in males and 1370 pg/mL of ww in females) and perfluorotetradecanoate (PFTeDA) (median of 370 pg/mL of ww in males and 210 pg/mL of ww in females) showed the slowest rate of telomere shortening. We also found that high blood concentrations of perfluorooctanoate (PFOA) (median of 120 pg/mL of ww in males and 150 pg/mL of ww in females) and perfluorohexanesulfonate (PFHxS) (median of 495 pg/mL of ww in males and 395 pg/mL of ww in females) were positively associated with higher re-sighting probabilities and apparent survival in males but not in females. Our work is the first to report an association between single PFAS compounds and telomeres, and the first to link PFAS exposure with survival probabilities, suggesting that the effect of PFAS exposure might be more tied to the type of compound rather than the total concentration of PFAS.

Diet quality may have an important effect on the regulation of oxidative status and the immune system during an infectious disease. However, the relationship among intake of specific dietary molecules, an individual’s oxidative status and the occurrence and progress of a viral disease remains almost unexplored in free‐living organisms. Here, we study a wild, long‐lived animal, the Magnificent frigatebird Fregata magnificens to investigate: (a) the differences in a number of physiological traits (biomarkers of blood oxidative status, corticosterone (CORT), immunity and inflammation) between sick and healthy nestlings; and (b) whether experimentally increased intake of resveratrol (a polyphenol with antioxidant and antiviral properties) affects these physiological markers during the progress of a severe viral disease. Birds with visible clinical signs showed higher oxidative damage, haemolysis and haemagglutination scores and lower antioxidant defences in comparison with birds without clinical signs. At the end of the experiment, supplemented birds showed the following: (a) increased plasma haptoglobin levels and circulating antioxidant defences; (b) reduced generation of lipid oxidative damage; and (c) negligible to no influence on immune markers, baseline CORT levels and activity of antioxidant enzymes. Our work illustrates how the availability of specific organic molecules in the diet may constrain the individuals’ capacity to cope with viral infections in free‐living animals. http://onlinelibrary.wiley.com/doi/10.1111/1365-2435.13195/suppinfo is available for this article.

Infectious diseases are one of the most common threats for both domestic and wild animals, but little is known about the effects on the physiological condition and survival of wild animals. Here, we have tested for the first time in a wild vertebrate facing a viral disease possibly due to herpesvirus (i) whether nestlings with either low levels of oxidative damage or high levels of antioxidant protection are less susceptible to develop visible clinical signs, (ii) whether the disease is associated with the nestlings’ oxidative status, (iii) whether the association between the disease and oxidative status is similar between males and females (iv), and whether cloacal and tracheal swabs might be used to detect herpesvirus. To address our questions, we took advantage of a population of Magnificent frigatebirds (Fregata magnificens) whose nestlings have experienced high mortality rates in recent times. Our work shows that (i) blood lipid oxidative damage is associated with observable clinical signs and survival probabilities of nestling frigatebirds, and (ii) that high glutathione levels in red blood cells are associated with the emergence of visible clinical signs of the disease. Our work provides evidence that differences in the oxidative status of nestlings might underlie individual health and survival.