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Background Lead, a serious threat for raptors, can hamper the success of their conservation. This study reports on experience with accidental lead intoxication and responses to chelation therapy in captive Cinereous ( Aegypius monachus ) and Egyptian ( Neophron percnopterus ) Vultures. Results Soil contamination by lead-based paint sanded off the steel aviary resulted in poisoning of eight Cinereous and two Egyptian Vultures. A male Egyptian Vulture developed signs of apathy, polydipsia, polyuria, regurgitation, and stupor, and died on the next day. Liver, kidney and blood lead concentrations were 12.2, 8.16 and 2.66 μg/g, respectively. Laboratory analyses confirmed severe liver and kidney damage and anaemia. Blood Pb levels of Pb-exposed Cinereous Vultures were 1.571 ± 0.510 μg/g shortly after intoxication, decreased to 0.530 ± 0.165 μg/g without any therapy in a month and to 0.254 ± 0.097 μg/g one month after CaNa 2 EDTA administration. Eight months later, blood lead levels decreased to close to the background of the control group. Blood parameters of healthy Pb-non-exposed Cinereous Vultures were compared with those of the exposed group prior to and after chelation therapy. Iron levels in the lead-exposed pre-treatment birds significantly decreased after chelation. Haematocrit levels in Pb-exposed birds were significantly lower than those of the controls and improved one month after chelation. Creatine kinase was higher in pre-treatment birds than in the controls but normalised after therapy. Alkaline phosphatase increased after chelation. A marked increase in the level of lipid peroxidation measured as thiobarbituric acid reactive species was demonstrated in birds both prior to and after chelation. The ferric reducing antioxidant power was significantly lower in pre-treatment vultures and returned to normal following chelation therapy. Blood metallothionein levels in lead-exposed birds were higher than in controls. Reduced glutathione dropped after CaNa 2 EDTA therapy, while oxidised glutathione was significantly lower in both pre- and post-treatment birds. A chick in an egg produced by a Cinereous Vulture female two months after lead toxicosis died on day 40 of artificial incubation. Lead concentrations in foetal tissues were consistent with levels causing avian mortality. Conclusions The reported blood parameters and reproduction impairment in captive birds may have implications for professionals dealing with lead exposure in wild birds.

All individuals are exposed to certain chemical, physical, biological, environmental as well as occupational factors. The data pertaining to role of these factors on female reproduction are scanty as compared to male. The available data suggest the adverse effects of certain toxicants, viz., metals such as lead, cadmium and mercury, pesticides such as bis(4-chlorophenyl)-1,1,1-trichloroethane and organic solvent such as benzene, toluene and ionizing radiation on the female reproductive system affecting directly the organ system or impacting in directly through hormonal impairments, molecular alterations, oxidative stress and DNA methylation impairing fertility as well as pregnancy and its outcomes. Thus, there is a need for awareness and prevention programme about the adverse effects of these factors and deterioration of female reproductive health, pregnancy outcome and offspring development as some of these chemicals might affect the developing foetus at very low doses by endocrine disruptive mechanism.

Pregnancy is a physiological cost of reproduction for animals that rely on fleeing to avoid predators. Costs of reproduction are predicted to differ between alternative reproductive strategies or modes, such as egg‐laying (oviparity) or live‐bearing (viviparity). However, disentangling the factors that comprise this cost and how it differs for oviparous or viviparous females is challenging due to myriad environmental, biological, and evolutionary confounds. Here, we tested the hypothesis that costs of pregnancy differ between oviparous and viviparous common lizards (Zootoca vivipara). We predicted that the degree of locomotor impairment during pregnancy and therefore the cost of reproduction would be higher in viviparous females. We conducted our experiment in a hybrid zone containing oviparous and viviparous common lizards. Due to the common environment and inclusion of hybrid individuals, we could infer whether differences were inherent to parity mode. We found that the average and maximum running speed of pregnant females was slower than after they had given birth or laid eggs. Viviparous females experienced an additional pregnancy weight burden and for a longer time period, but were not slower at running than pregnant oviparous females. In addition, we found a parity mode‐specific effect of reproductive investment; producing larger clutches was costlier for the locomotor performance of viviparous females for reasons other than the mass increase. Locomotor costs were found to be intermediate in hybrid females, indicating that they are specific to each reproductive mode. Our study shows that viviparous females experience an additional physical and physiological cost of pregnancy and reproductive investment. This two‐fold cost implies that viviparous females modulate resource allocation decisions and/or adjust their behavioural responses that result from locomotor impairment. In a powerful design controlling phylogeny and environment, we show that pregnant females experience higher locomotor costs for viviparity than oviparity, for reasons other than the mass increase of clutch size. Performance costs are consistently intermediate in hybrid females, demonstrating they are inherent to the reproductive mode.

The fungicide difenoconazole, widely used to reduce the negative impacts of fungi diseases on areas with intensive farming, can reach freshwater systems causing deleterious effects on nontarget organisms. The acute and chronic toxicity of a commercial formulation containing 250 g L −1 of difenoconazole (Prisma®) as the active ingredient was assessed in the freshwater planarian Girardia tigrina . The endpoints evaluated were feeding rate, locomotion, regeneration, and sexual reproduction of planarians. The estimated 48 h LC 50 of the commercial formulation on planarians expressed as the concentration of the active ingredient difenoconazole was 47.5 mg a.i.L −1 . A significant decrease of locomotion (LOEC = 18.56 mg a.i.L −1 ), delayed regeneration (LOEC = 9.28 mg a.i.L −1 ), and sexual reproduction impairment, i.e., decreased fecundity and fertility rates (LOEC ≤ 1.16 mg a.i.L −1 ) were observed on planarians exposed to sublethal concentrations of the formulation. This study demonstrated the importance of using reproductive, physiological, and behavioral parameters as more sensitive and complementary tools to assess the deleterious effects induced by a commercial formulation of difenoconazole on a nontarget freshwater organism. The added value and importance of our research work, namely, the impairment of sexual reproduction of planarians, contributes to the development of useful tools for ecotoxicology and highlights the fact that those tools should be developed as guidelines for testing of chemicals. Our results showed that the use of reproductive parameters of Girardia tigrina would help to complement and achieve a better assessment of the risk posed by triazole fungicides to freshwater ecosystems.

The functions of sleep remain elusive. Extensive evidence suggests that sleep performs restorative processes that sustain waking brain performance. An alternative view proposes that sleep simply enforces adaptive inactivity to conserve energy when activity is unproductive. Under this hypothesis, animals may evolve the ability to dispense with sleep when ecological demands favor wakefulness. Here, we show that male pectoral sandpipers (Calidris melanotos), a polygynous Arctic breeding shorebird, are able to maintain high neurobehavioral performance despite greatly reducing their time spent sleeping during a 3-week period of intense male-male competition for access to fertile females. Males that slept the least sired the most offspring. Our results challenge the view that decreased performance is an inescapable outcome of sleep loss.

1. Pesticide exposure has been implicated as a contributor to insect pollinator declines. In social bees, which are crucial pollination service providers, the effect of low-level chronic exposure is typically non-lethal leading researchers to consider whether exposure induces sublethal effects on behaviour and whether such impairment can affect colony development. 2. Studies under laboratory conditions can control levels of pesticide exposure and elucidate causative effects, but are often criticized for being unrealistic. In contrast, field studies can monitor bee responses under a more realistic pesticide exposure landscape; yet typically such findings are limited to correlative results and can lack true controls or sufficient replication. We attempt to bridge this gap by exposing bumblebees to known amounts of pesticides when colonies are placed in the field. 3. Using 20 bumblebee colonies, we assess the consequences of exposure to the neonicotinoid clothianidin, provided in sucrose at a concentration of five parts per billion, over 5 weeks. We monitored foraging patterns and pollen collecting performance from 3282 bouts using either a non-invasive photographic assessment, or by extracting the pollen from returning foragers. We also conducted a full colony census at the beginning and end of the experiment. 4. In contrast to studies on other neonicotinoids, showing clear impairment to foraging behaviours, we detected only subtle changes to patterns of foraging activity and pollen foraging during the course of the experiment. However, our colony census measures showed a more pronounced effect of exposure, with fewer adult workers and sexuals in treated colonies after 5 weeks. 5. Synthesis and applications. Pesticide-induced impairments on colony development and foraging could impact on the pollination service that bees provide. Therefore, our findings, that bees show subtle changes in foraging behaviour and reductions in colony size after exposure to a common pesticide, have important implications and help to inform the debate over whether the benefits of systemic pesticide application to flowering crops outweigh the costs. We propose that our methodology is an important advance to previous semi-field methods and should be considered when considering improvements to current ecotoxicological guidelines for pesticide risk assessment.

Perfluorooctane sulfonate (PFOS) is a synthetic material that has been widely used in industrial applications for decades. Exposure to PFOS has been associated with decreased adult testosterone level, and Leydig cell impairment during the time of adulthood. However, little is known about PFOS effects in utero on fetal Leydig cells (FLC). The present study investigated effects of PFOS on FLC function. Pregnant Sprague Dawley female rats received vehicle (0.05% Tween20) or PFOS (5, 20 mg/kg) by oral gavage from gestational day (GD) 11-19. At GD20, testosterone (T) production, FLC numbers and ultrastructure, testicular gene and protein expression levels were examined. The results indicate that exposures to PFOS have affected FLC function as evidenced by decreased T production, impaired FLC, reduced FLC number, and decreased steroidogenic capacity and cholesterol level in utero. The present study shows that PFOS is an endocrine disruptor of male reproductive system as it causes reduction of T production and impairment of rat fetal Leydig cells.

Spray adjuvants are often applied to crops in conjunction with agricultural pesticides in order to boost the efficacy of the active ingredient(s). The adjuvants themselves are largely assumed to be biologically inert and are therefore subject to minimal scrutiny and toxicological testing by regulatory agencies. Honey bees are exposed to a wide array of pesticides as they conduct normal foraging operations, meaning that they are likely exposed to spray adjuvants as well. It was previously unknown whether these agrochemicals have any deleterious effects on honey bee behavior. An improved, automated version of the proboscis extension reflex (PER) assay with a high degree of trial-to-trial reproducibility was used to measure the olfactory learning ability of honey bees treated orally with sublethal doses of the most widely used spray adjuvants on almonds in the Central Valley of California. Three different adjuvant classes (nonionic surfactants, crop oil concentrates, and organosilicone surfactants) were investigated in this study. Learning was impaired after ingestion of 20 µg organosilicone surfactant, indicating harmful effects on honey bees caused by agrochemicals previously believed to be innocuous. Organosilicones were more active than the nonionic adjuvants, while the crop oil concentrates were inactive. Ingestion was required for the tested adjuvant to have an effect on learning, as exposure via antennal contact only induced no level of impairment. A decrease in percent conditioned response after ingestion of organosilicone surfactants has been demonstrated here for the first time. Olfactory learning is important for foraging honey bees because it allows them to exploit the most productive floral resources in an area at any given time. Impairment of this learning ability may have serious implications for foraging efficiency at the colony level, as well as potentially many social interactions. Organosilicone spray adjuvants may therefore contribute to the ongoing global decline in honey bee health.

The blood meal of the female malaria mosquito is a pre-requisite to egg production and also represents the transmission route for the malaria parasite. The proper and rapid assimilation of proteins and nutrients in the blood meal creates a significant metabolic challenge for the mosquito. To better understand this process we generated a global profile of metabolite changes in response to blood meal of Anopheles gambiae, using Gas Chromatography-Mass Spectrometry (GC-MS). To disrupt a key pathway of amino acid metabolism we silenced the gene phenylalanine hydroxylase (PAH) involved in the conversion of the amino acid phenylalanine into tyrosine. We observed increased levels of phenylalanine and the potentially toxic metabolites phenylpyruvate and phenyllactate as well as a reduction in the amount of tyrosine available for melanin synthesis. This in turn resulted in a significant impairment of the melanotic encapsulation response against the rodent malaria parasite Plasmodium berghei. Furthermore silencing of PAH resulted in a significant impairment of mosquito fertility associated with reduction of laid eggs, retarded vitellogenesis and impaired melanisation of the chorion. Carbidopa, an inhibitor of the downstream enzyme DOPA decarboxylase that coverts DOPA into dopamine, produced similar effects on egg melanization and hatching rate suggesting that egg chorion maturation is mainly regulated via dopamine. This study sheds new light on the role of amino acid metabolism in regulating reproduction and immunity.

Many animals communicate using multiple sensory channels simultaneously and this ability enables them to overcome the challenges of living in variable environments. Studies of wolf spiders have been important in understanding complex communication with a primary focus on the roles of visual and vibratory signals during mating. However, it is well documented that wolf spiders leave silk draglines behind that are often associated with additional chemical residues such as pheromones. We verified that females detect the silk and secretions left on a substrate by male wolf spiders in the species, Tigrosa helluo. We hypothesized that male chemotactile cues play different roles when vision is limited and so we explored the effects of adding male cues prior to courtship in light vs dark situations. Aggression was lower when male chemotactile cues were augmented and when vision was reduced. Males and females came together more quickly and had higher mating success when male cues were augmented under red light, which simulated darkness for these spiders, whereas contact was delayed and mating success was lower in the treatment with added male cues in white light. Thus, the availability of visual signals adjusted the importance of male chemotactile cues either through a shift in sensory priorities of the female or in the evaluative criteria used to make decisions. Chemotactile cues potentially allow for sophisticated information to be conveyed about the male, as such, may be an important communication modality on their own as well as in concert with other signaling channels.Significance statementSelecting the right mate depends on effective communication so that the prospective partner can detect and accurately evaluate key traits. Animals living in variable habitats must overcome the communication challenges by presenting information through multiple sensory channels. The understanding of multimodal communication has been advanced by studies of visual and vibratory signaling in wolf spiders. We found that females detect male silk and chemical secretions and that they alter mating interactions in the wolf spider, Tigrosa helluo. Allowing males to deposit silk and chemical cues before virgin males and females were allowed to interact reduced aggression and increased mating success in red light (low vision) conditions. These results broaden the possibilities for the types of interacting signals that might influence the efficacy of multimodal communication in animals live and mate in dynamic environments.