Biological matrices for sampling free‐ranging cetaceans and the implications of their use for reproductive endocrine monitoring

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粪便类固醇激素检测准确性的影响因素

近年来,采用非损伤性取样方法监测野生动物的生理状况越来越受到重视。本文对检测过程中影响动物粪便类固醇激素检测准确性的因素进行了分析总结,包括样品的新鲜程度、样品量和保存方法;激素代谢的日节律和季节性变化;动物的年龄、性别和繁殖状态等,以期为粪便类固醇激素检测技术在野生动物中的准确应用提供借鉴。     

Sex and wildlife: the role of reproductive science in conservation

This essay explains the role of reproductive science, including what are termed reproductive technologies (i.e. artificial insemination, in vitro fertilization, embryo transfer, cloning), in conservation biology. Reproductive techniques (high- and low-tech) find their greatest application in understanding species uniqueness, adaptations and physiological mechanisms, not in the large-scale assisted breeding and the production of offspring. Models of how to use these tools to study reproductive fitness are emerging to help insure gene diversity and even propagate endangered species, but only after fundamental databases have been developed. Examples are provided of how non-invasive hormone metabolite monitoring, artificial insemination and genome resource banking are being used ex situ and in situ to understand wildlife biology. We predict that as the fundamental, multi-species database grows, so will the applied benefits for: (1) developing genome banks for insuring extant genetic diversity; (2) assessing the relationship of physiology, behaviour and environmental perturbations; (3) managing small populations; and (4) dealing with dilemmas ranging from contraception to skewed sex ratios to animal welfare. Most progress will be made in using these tools in systematic studies to solve the mystery of how thousands of unstudied species reproduce. Carried out appropriately, financial costs will be consistent with any approach for generating sound scientific knowledge.     

Alligators and Endocrine Disrupting Contaminants: A Current Perspective

Many xenobiotic compounds introduced into the environment byhuman activity have been shown to adversely affect wildlife.Reproductive disorders in wildlife include altered fertility,reduced viability of offspring, impaired hormone secretion oractivity and modified reproductive anatomy. It has been hypothesizedthat many of these alterations in reproductive function aredue to the endocrine disruptive effects of various environmentalcontaminants. The endocrine system exhibits an organizationaleffect on the developing embryo. Thus, a disruption of the normalhormonal signals can permanently modify the organization andfuture function of the reproductive system. We have examinedthe reproductive and developmental endocrinology of severalpopulations of American alligator (Alligator mississippiensis)living in contaminated and reference lakes and used this speciesas a sentinel species in field studies. We have observed thatneonatal and juvenile alligators living in pesticide-contaminatedlakes have altered plasma hormone concentrations, reproductivetract anatomy and hepatic functioning. Experimental studiesexposing developing embryos to various persistent and nonpersistentpesticides, have produced alterations in gonadal steroidogenesis,secondary sex characteristics and gonadal anatomy. These experimentalstudies have begun to provide the causal relationships betweenembryonic pesticide exposure and reproductive abnormalitiesthat have been lacking in pure field studies of wild populations.An understanding of the developmental consequences of endocrinedisruption in wildlife can lead to new indicators of exposureand a better understanding of the most sensitive life stagesand the consequences of exposure during these periods.     

Introduction. Integration of ecology and endocrinology in avian reproduction: a new synthesis

Birds are some of the most familiar organisms of global ecosystems. Changes in the visibility and abundance of birds are therefore excellent indicators of population and physiological responses to habitat changes and are a major focus for public concern about detrimental environmental changes. In order to understand how birds respond to these challenges, it is essential to determine how the environment affects reproduction under natural conditions. The continuum from environmental variables (cues) to reproductive life-history traits depends upon a cascade of neural and physiological processes that determine the extent and rate at which birds will be able to adapt to changes in their environment. For a full understanding of this ability to adapt, ecologists and endocrinologists need to collaborate and build a common framework. The objective of this theme issue is to bring together a series of papers addressing how evolutionary ecologists and endocrinologists can collaborate directly using avian reproduction as a model system. First, we address the need to integrate ecology and endocrinology and what benefits to biological knowledge will be gained. The papers collected in this issue represent a new synthesis of ecology and endocrinology as discussed in three E-BIRD workshops. The three main foci are trade-offs and constraints, maternal effects and individual variation. Authors within each group present ecological and endocrinological aspects of their topics and many go on to outline testable hypotheses. Finally, we discuss where the major problems remain and how this issue points out where these need collaborative efforts of ecologists and endocrinologists. Specific challenges are raised to future researchers to break through intellectual barriers and explore new frontiers. This framework of topics will ultimately apply to all taxa because the principles involved are universal and hopefully will have direct application to programmes integrating organisms and genes throughout biological sciences.     

Evaluating the utility of an accelerometer and urinary hormone analysis as indicators of estrus in a Zoo-housed koala (Phascolarctos cinereus)

Induced ovulators, such as the koala, do not always have overt signs of estrus, which makes pairing these animals for breeding purposes difficult to achieve in a zoo setting. This study examined the possibility of using alternative methods to behavioral sampling and weight fluctuations for monitoring estrus in a female koala of reproductive age. We attempt to gain an improved understanding of koala estrus and enhance our ability to detect it by combining a noninvasive technique for hormone analysis with a newer method for recording activity level. The findings suggest that activity levels were accurately measured using an accelerometer and increased activity was associated with one estrus behavior, bellowing. Weekly weight declines occur with increases in activity registered from the accelerometer. We also validated an assay to detect progesterone and estradiol in female koala urine in an attempt to detect an estrus spike. However, neither urinary concentrations of estradiol nor progesterone was associated with behavioral cues of estrus in our subject. We suggest that increased female activity, bellowing, and weight loss all indicate a pro-estrus state that requires proper male stimulation in order to achieve a full estrus display. Zoo Biol 28:59–68, 2009. ©2008 Wiley-Liss, Inc.     

Urinary steroid evaluations to monitor ovarian function in exotic ungulates: VIII. Correspondence of urinary and plasma steroids in the llama (Lama glama) during nonconceptive and conceptive cycles

Ovarian function was evaluated in mature female llamas (n = 2) during seven ovulations in 2 conceptive and 5 nonconceptive ovarian cycles by measuring urinary and plasma hormone concentrations. Ovulation was induced by three different methods; administration of gonadotropin-releasing hormone (GnRH), copulation with a vasectomized male and copulation with an intact male. Plasma estradiol and progesterone concentrations, and urinary concentrations of estrogen conjugates and two progesterone metabolites, pregnanediol-3-glucuronide (PdG), and immunoreactive (iPdG), concentrations were compared to determine their value in monitoring ovarian function. Estrogen concentrations in urine corresponded to estradiol levels in plasma and accurately reflected changes in follicular activity when evaluated over several daily samples. Plasma progesterone and urinary iPdG were reliable indicators of luteal function. These data represent the first comparison of blood and urinary hormone measurements for monitoring the complete ovarian cycle of an ungulate, and demonstrates that either can be used to assess changes in ovarian activity in this species.     

大熊猫尿液类固醇激素研究现状及展望

概述了大熊猫尿液样本采集和保存方法,系统总结了大熊猫尿液类固醇激素的提取方法、测定方法以及大熊猫尿液类固醇激素在应激反应监测、发情期监测及最佳配种时间选择、雌性卵巢功能和妊娠监测、雄性繁殖力评估等方面的应用研究,结合前人的研究工作,对大熊猫尿液类固醇激素的应用前景进行展望.     

Class incremental learning for wildlife biodiversity monitoring in camera trap images

Camera traps have been widely used for wildlife biodiversity monitoring, providing abundant ecological data. Manually classifying such abundant images is time-consuming and labor-intensive. Existing deep learning methods solve this problem for a fixed set of predefined wildlife species. The model trained on such sets cannot be applied to new wildlife species. Retraining models on new wildlife species can lead to catastrophic forgetting. Thus, in this work, we propose a class incremental learning method to identify new wildlife species. Our method employs a novel adaptive exemplar assignment (AEA) strategy with dynamic exemplar amounts to adapt to new species while alleviating the forgetting of old ones. Due to memory constraints, the data imbalance between limited exemplars and new species data can lead to class bias. We mitigate it by performing center vector retrieval (CVR) to classify samples in feature space and bypass the biased linear classifier. In addition, we propose two variants of CVR that incorporate the advantage of the linear classifier to further improve the performance. By using only 4% of old species data, our method achieves 77.09% accuracy at a low computational resource for recognition. Through extensive experiments and ablations, we demonstrate the superiority of our proposed approach over state-of-the-art methods. This method facilitates wildlife monitoring, biodiversity conservation, and ecological assessment.     

Transplantation of young ovaries restored cardioprotective influence in postreproductive-aged mice

The female cardioprotective advantage, present in mammals of a reproductively competent age, is lost during the transition to a postreproductive state. The role of reproductive hormones in this transition is most evident in women with premature ovarian failure, where reduced estrogen production has been associated with an increased incidence of early death from cardiovascular disease. Previously, we reported that postreproductive-aged mice that received young ovaries displayed an increased life span. Subsequent histopathological analysis suggested the presence of a cardioprotective effect associated with the restoration of ovarian influence. This restoration in postreproductive-aged mice produced a sharp decrease in evidence of significant cardiomyopathy at death, compared with sham-transplanted mice (36.0% vs. 73.3%, respectively). Within the intact transplant group, evidence of cardiomyopathy at death was decreased in mice that were reproductively cycling at the time of transplant, compared with acyclic mice (26.7% vs. 50.0%, respectively). This observation reflects the importance of timing in restoration of ovarian influence in this study. Transplantation of young ovaries to intact, postreproductive-aged female mice provided significant, long-term restoration of a cardioprotective benefit, similar to that previously present during a reproductively competent age. In these mice, restoration of ovarian influence through ovarian transplantation may, in effect, have postponed the advance of age-associated cardiomyopathy to a point where the disease did not reach a clinically relevant threshold during the lifetime of the recipients. These results offer support for previous clinical observations suggesting that hormone replacement therapy can produce divergent results if initiated during the perimenopausal period, compared with the postmenopausal ages.     

Reproductive physiology studies in zoological species: Concerns and strategies

A sophisticated understanding of reproductive physiology of domestic animals has evolved over only the past several decades. Related technical advances in this field have permitted propagation through artificial insemination and/or embryo transfer using fresh or frozen-thawed gametic or embryonic material. More recent studies in genetic engineering and embryo micromanipulation have generated additional potential for improved reproductive efficiency in the farm-animal industry. Although these procedures provide incentive for solving management problems and improving the endangered status of many zoological species, achieving these objectives will be neither simple nor immediate. Major obstacles to confront include the poor image of research, unavailability of research stocks, lack of financial support, scarcity of trained personnel, and the idea that new reproductive techniques offer a “quick fix” to the problem of inadequate reproduction in an endangered species. Zoological researchers should now concentrate on establishing basic reproductive relationships in species of interest. Comparative studies in domesticated animals will accelerate progress. The immediate goal should be the production of sound scientific data of publishable quality. Only then can artificial propagation be considered as a viable alternative to preserving wildlife species.     

蛋白质芯片技术进展

人类基因组测序工作的完成 ,引起人们对蛋白质组研究的热忱。蛋白质作为生命活动的执行者 ,种类繁多 ,结构复杂 ,并且其活性与空间结构密切相关 ,需要更为先进的技术去研究和探索。近来出现的蛋白质芯片以并行、高通量检测、分析和处理蛋白质样品 ,发展迅速 ,应用前景广泛。介绍蛋白质芯片的种类、蛋白质固定的表面化学以及不同的检测方法 ,简述蛋白质芯片在不同领域的应用 ,并讨论蛋白质芯片目前存在的问题。     

Reproductive characteristics of wild female Phayre's leaf monkeys

Understanding female reproductive characteristics is important for assessing fertility, interpreting female behavior, and designing appropriate conservation and captive management plans. In primate species lacking morphological signs of receptivity, such as most colobines, determination of reproductive parameters depends on the analysis of reproductive hormones. Here, we use fecal hormone analysis to characterize cycle patterns (N=6 females) and gestation length (N=7 females) in a group of wild Phayre's leaf monkeys (Trachypithecus phayrei crepusculus) in Phu Khieo Wildlife Sanctuary, Thailand. We found that both fecal estrogen (fE) and progestin (fP) levels showed clear biological patterns indicative of ovulation and conception. However, because fP patterns were inadequate in determining the end of the luteal phase, we used fE rather than fP patterns to delineate menstrual cycle parameters. We found a mean cycle length of 28.4 days (N=10), with follicular and luteal phases of 15.4 (N=10) and 12.5 days (N=14), respectively. On average, females underwent 3.57 (N=7) cycles until conception. Average gestation length was 205.3 days (N=7), with fE levels increasing over the course of pregnancy. Overall, the reproductive characteristics found for Phayre's leaf monkeys were consistent with results for other colobine species, suggesting that fecal hormone monitoring, particularly for fE metabolites, can provide useful reproductive information for this species. Am. J. Primatol. 72:1073–1081, 2010. © 2010 Wiley‐Liss, Inc.     

Lighting up the cell surface with evanescent wave microscopy.

Evanescent wave microscopy, also termed total internal reflection fluorescence microscopy (TIR-FM), has shed new light on important cellular processes taking place near the plasma membrane. For example, this technique can enable the direct observation of membrane fusion of synaptic vesicles and the movement of single molecules during signal transduction. There has been a recent surge in the popularity of this technique with the advent of green-fluorescent protein (GFP) as a fluorescent marker and new technical developments. These technical developments and some of the latest applications of TIR-FM are the subject of this review.     

Ecological correlates of the popularity of birds and butterflies in Internet information resources

The success of conservation programs depends on using appropriate methods to demonstrate the importance of conservation to society. For example, flagship species are among the key marketing tools to motivate public support. However, they are rarely selected in a systematic, manner. In this study we addressed the issue of the colonization of human information resources by birds and butterflies in the context of wildlife conservation. We used a simple method to measure the popularity of species based on Google browsing and made an attempt to link biological characteristics of the species with their popularity in human information resources. Biological traits of species contributed significantly to explaining the occupancy (invasion) of cyberspace by the species. Commonness and body size of the species appeared to be the most informative predictors of their Google score. We believe that these results may be used by conservation organizations to assist in the selection of flagship/charismatic species, and their use in logos, for TV programs or for other public presentations. Moreover, we showed that some biological traits can affect the popularity of wildlife in society and in virtual resources.     

野生动物监测技术和方法应用进展与展望

野生动物是生态系统研究和保护管理的重要生物类群, 对调控生态系统结构和功能, 维持生态系统健康平衡具有显著作用。科学监测数据是野生动物研究、保护、管理决策的前提基础, 但由于传统监测技术的限制, 野生动物的多样性特征及其与环境、生态系统的平衡机制未得到充分关注和研究。随着自动化、智能化、信息化技术的发展及应用, 野生动物监测技术和方法出现较大突破和变革。该文论述了近年来野生动物监测研究领域的重要新技术, 包括红外相机技术、全球定位系统(GPS)追踪技术、DNA条形码技术和高通量测序技术等。通过综合介绍相关的基础概念、基本原理, 该文总结了新技术的应用优势和重大应用进展, 同时探讨了新技术应用中存在的问题, 并对未来野生动物监测技术的发展趋势进行了展望。     

Medicating the environment: assessing risks of pharmaceuticals to wildlife and ecosystems

Global pharmaceutical consumption is rising with the growing and ageing human population and more intensive food production. Recent studies have revealed pharmaceutical residues in a wide range of ecosystems and organisms. Environmental concentrations are often low, but pharmaceuticals typically are designed to have biological effects at low doses, acting on physiological systems that can be evolutionarily conserved across taxa. This Theme Issue introduces the latest research investigating the risks of environmentally relevant concentrations of pharmaceuticals to vertebrate wildlife. We take a holistic, global view of environmental exposure to pharmaceuticals encompassing terrestrial, freshwater and marine ecosystems in high- and low-income countries. Based on both field and laboratory data, the evidence for and relevance of changes to physiology and behaviour, in addition to mortality and reproductive effects, are examined in terms of the population- and community-level consequences of pharmaceutical exposure on wildlife. Studies on uptake, trophic transfer and indirect effects of pharmaceuticals acting via food webs are presented. Given the logistical and ethical complexities of research in this area, several papers focus on techniques for prioritizing which compounds are most likely to harm wildlife and how modelling approaches can make predictions about the bioavailability, metabolism and toxicity of pharmaceuticals in non-target species. This Theme Issue aims to help clarify the uncertainties, highlight opportunities and inform ongoing scientific and policy debates on the impacts of pharmaceuticals in the environment.     

Assaying progesterone,estradiol and cortisol concentrations in hair of Père David deer hinds: an alternative way to reflect seasonality of steroid secretion

The use of a hair hormone concentration assay is increasingly recognized as a useful and noninvasive technique for monitoring the endocrinological status of animals. However, few studies have focused on reproductive and stress hormones together. We used a chemiluminescent immunoassay to determine whether the progesterone, estradiol, and cortisol concentrations could be measured from hair and whether these hormone concentrations varied in different hair segments of captive Père David deer hinds. We found that progesterone, estradiol, and cortisol could be measured in the hair samples and that the progesterone concentration varied but the estradiol and cortisol concentrations did not among different hair segments. Contrary to the segmental decline in hair cortisol found in many studies, we found that progesterone concentration was higher near the tip than at the base of hair in Père David deer. This suggests that the variation in segmental hair steroid hormone concentration in seasonal molting animals may be mainly due to internal reproductive cycles and that hair steroid hormones may reflect long-term physiological changes and can thus be used for the conservation and management of wildlife.     

Current strategies for characterization of mucin-domain glycoproteins

Glycosylation, and especially O-linked glycosylation, remains a critical blind spot in the understanding of post-translational modifications. Due to their nature as proteins defined by a large density and abundance of O-glycosylation, mucins present extra challenges in the analysis of their structure and function. However, recent breakthroughs in multiple areas of research have rendered mucin-domain glycoproteins more accessible to current characterization techniques. In particular, the adaptation of mucinases to glycoproteomic workflows, the manipulation of cellular glycosylation pathways, and the advances in synthetic methods to more closely mimic mucin domains have introduced new and exciting avenues to study mucin glycoproteins. Here, we summarize recent developments in understanding the structure and biological function of mucin domains and their associated glycans, from glycoproteomic tools and visualization methods to synthetic glycopeptide mimetics.     

Conservation and behavioral neuroendocrinology

The total number of threatened species of vertebrates is likely to be more than 10,000, with approximately one quarter of the world's mammal species, one eighth of the birds and one third of the amphibians threatened with extinction. The rate of loss of animal species and hence of biodiversity is increasing and may become even greater as ecosystems become affected by climate change due to global warming. Behavioral neuroendocrinology, which considers interactions between behavior and neuroendocrine function in animals from all vertebrate taxa, can contribute to animal conservation. Research with laboratory animals can address questions in basic biology relevant to conservation and develop methods for use with threatened animals. Field work with free-living animals considers the basic biology of new species and the use of endocrine tools to assess the susceptibility of species to threats. Non-invasive measurements of hormone concentrations, especially fecal steroids, are extensively used to assess reproductive function and the stress status of animals in captive breeding programs and in the wild. Biodiversity and natural selection both depend on individual variation, and conservation programs often work with animals on an individual basis. The consideration of data from individuals is essential in conservation endocrinology. Direct contributions to conservation programs are challenging as study situations are determined by practical conservation concerns. Indirect contributions such as the provision of scientific input to conservation plans and participation in public education programs offer significant benefits for conservation programs. Directly and indirectly, there are many opportunities for behavioral neuroendocrinologists to contribute to conservation.