Artificial reproduction of two different spawn-forms of the chub.

PubMed

Krejszeff, Sławomir; Targońska, Katarzyna; Zarski, Daniel; Kucharczyk, Dariusz

2010-03-01

The aim of this study was to compare, under controlled conditions, reproduction results of cultured and wild stock of the chub. Wild fish spawned only once a season whereas the cultured stock spawned at least two times. In the multiple-spawn stock, fewer fish spawned and the weight of produced oocytes was reduced compared to the single-spawn stock. Larvae obtained from the multi-spawn forms were smaller than those of the single-spawn stock. The occurrence of one species with two forms of spawning performance in the same area makes it difficult to develop an efficient method for controlling the reproduction.

Metabolizable protein supply alters pregnancy and subsequent retention rate during heifer development while grazing dormant winter forage

USDA-ARS?s Scientific Manuscript database

Type of heifer development system can have major impact on the future productivity and retention rate of the cowherd. Therefore, the objective of this experiment was to determine growth, reproductive performance, retention rate, and economic efficiency of heifer’s developed in a range raised (with ...

Nuclear Receptor Coactivator Function in Reproductive Physiology and Behavior

PubMed Central

Molenda, Heather A.; Kilts, Caitlin P.; Allen, Rachel L.; Tetel, Marc J.

2009-01-01

Gonadal steroid hormones act throughout the body to elicit changes in gene expression that result in profound effects on reproductive physiology and behavior. Steroid hormones exert many of these effects by binding to their respective intracellular receptors, which are members of a nuclear receptor superfamily of transcriptional activators. A variety of in vitro studies indicate that nuclear receptor coactivators are required for efficient transcriptional activity of steroid receptors. Many of these coactivators are found in a variety of steroid hormone-responsive reproductive tissues, including the reproductive tract, mammary gland, and brain. While many nuclear receptor coactivators have been investigated in vitro, we are only now beginning to understand their function in reproductive physiology and behavior. In this review, we discuss the general mechanisms of action of nuclear receptor coactivators in steroid-dependent gene transcription. We then review some recent and exciting findings on the function of nuclear receptor coactivators in steroid-dependent brain development and reproductive physiology and behavior. PMID:12855594

Anopheline Reproductive Biology: Impacts on Vectorial Capacity and Potential Avenues for Malaria Control.

PubMed

Mitchell, Sara N; Catteruccia, Flaminia

2017-12-01

Vectorial capacity is a mathematical approximation of the efficiency of vector-borne disease transmission, measured as the number of new infections disseminated per case per day by an insect vector. Multiple elements of mosquito biology govern their vectorial capacity, including survival, population densities, feeding preferences, and vector competence. Intriguingly, biological pathways essential to mosquito reproductive fitness directly or indirectly influence a number of these elements. Here, we explore this complex interaction, focusing on how the interplay between mating and blood feeding in female Anopheles not only shapes their reproductive success but also influences their ability to sustain Plasmodium parasite development. Central to malaria transmission, mosquito reproductive biology has recently become the focus of research strategies aimed at malaria control, and we discuss promising new methods based on the manipulation of key reproductive steps. In light of widespread resistance to all public health-approved insecticides targeting mosquito reproduction may prove crucial to the success of malaria-eradication campaigns. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

Teaching Competencies Efficiently through the Internet--A Practical Example

ERIC Educational Resources Information Center

Caniels, Marjolein C. J.

2005-01-01

Universities increasingly adopt innovative teaching models, which focus on the development of skills instead of the reproduction of knowledge. These new teaching models emphasise the importance of knowledge application and the development of competencies. Yet, using these teaching methods usually implies a high assessment burden for lecturers.…

Energetics of growth and reproduction in a high-tidal population of the clam Ruditapes decussatus from Urdaibai Estuary (Basque Country, N. Spain)

NASA Astrophysics Data System (ADS)

Urrutia, M. B.; Ibarrola, I.; Iglesias, J. I. P.; Navarro, E.

1999-08-01

Energetics of growth and reproduction were studied in a high-tidal population of the clam Ruditapes decussatus living in the Mundaka Estuary in the Biosphere Reserve of Urdaibai (Basque Country, North Spain). The study included an analysis of growth rings on the shells to establish the growth curve as well as seasonal patterns of growth and body condition, and estimates of the breeding cycle including quantification of the reproductive output and reproductive effort. The simultaneous determination of the seasonal course of metabolism allowed estimates of assimilation, growth efficiency and reproductive costs. Growth rates were consistently lower in this population than in other populations from similar latitudes, and this effect is interpreted in terms of nutritional restrictions caused by the high tidal position of the population. Assimilation rapidly increased from March to July, as a consequence of optimal nutritional conditions and increasing water temperatures. Somatic growth (spring) and gonadal development (early summer) both took place during this period. Negative growth was restricted to the winter and late summer and was associated with poor nutritional conditions (winter) and high rates of metabolic expenditure induced by high temperatures (late summer). Net growth efficiencies (ranging from 27% in 1-y-old to 6% in 7-y-old individuals) ranked among the lowest recorded for populations of marine bivalves. Reduced reproductive-effort values were consistent with the poor growing conditions that appeared to characterise this population of clams.

Distribution of potato spindle tuber viroid in reproductive organs of petunia during its developmental stages.

PubMed

Matsushita, Yosuke; Tsuda, Shinya

2014-09-01

Embryo infection is important for efficient seed transmission of viroids. To identify the major pattern of seed transmission of viroids, we used in situ hybridization to histochemically analyze the distribution of Potato spindle tuber viroid (PSTVd) in each developmental stage of petunia (flowering to mature seed stages). In floral organs, PSTVd was present in the reproductive tissues of infected female × infected male and infected female × healthy male but not of healthy female × infected male before embryogenesis. After pollination, PSTVd was detected in the developed embryo and endosperm in all three crosses. These findings indicate that PSTVd is indirectly delivered to the embryo through ovule or pollen during the development of reproductive tissues before embryogenesis but not directly through maternal tissues as cell-to-cell movement during embryogenesis.

Energetic Constraints on Fungal Growth.

PubMed

Heaton, Luke L M; Jones, Nick S; Fricker, Mark D

2016-02-01

Saprotrophic fungi are obliged to spend energy on growth, reproduction, and substrate digestion. To understand the trade-offs involved, we developed a model that, for any given growth rate, identifies the strategy that maximizes the fraction of energy that could possibly be spent on reproduction. Our model's predictions of growth rates and bioconversion efficiencies are consistent with empirical findings, and it predicts the optimal investment in reproduction, resource acquisition, and biomass recycling for a given environment and timescale of reproduction. Thus, if the timescale of reproduction is long compared to the time required for the fungus to double in size, the model suggests that the total energy available for reproduction is maximal when a very small fraction of the energy budget is spent on reproduction. The model also suggests that fungi growing on substrates with a high concentration of low-molecular-weight compounds will not benefit from recycling: they should be able to grow more rapidly and allocate more energy to reproduction without recycling. In contrast, recycling offers considerable benefits to fungi growing on recalcitrant substrates, where the individual hyphae are not crowded and the time taken to consume resource is significantly longer than the fungus doubling time.

The Efficiency of Reproduction Health Education Given to Adolescents during the Postpartum Period.

PubMed

Topatan, Serap; Demirci, Nurdan

2015-10-01

Our research, partly experimental and partly prospective, was conducted for the purpose of evaluating the efficiency of reproductive health education given to adolescents during the postpartum period. The study comprised with 120 adolescents aged 15 to 19 (60 experimental group, 60 control group). Follow-up was conducted every 3 months for a total of 12 months, and the study concluded with 55 individuals from the experimental group and 46 individuals from the control group having participated fully, for the full 12 months. At the end of the research, it was found that the reproductive health knowledge of the experimental (103.10 ± 11.43) and control (99.15 ± 9.53) groups were similar before education. A statistically significant difference was also found between the total points for the scale determining the reproductive health of the experimental and control groups before and after education (P < .001). The socio-demographic variables affecting the total points for the scale determining the reproductive health-protective behavior of women were evaluated by multiple regression analysis; the most effective variables were found to be age and educational status. A statistically significant difference was also found between the total points for the family planning behavior scale of the experimental and control groups before and after education (P < .001). From this, it was understood that reproductive health education given during the postpartum and follow-up periods has a positive effect on adolescents' developing reproductive health behaviors and on creating knowledge and awareness related to family planning behavior. But there needs to be follow-up and supporting specific for adolescents in the current health system. Copyright © 2015 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

Impact of reproductive efficiency over time and mare financial value on economic returns among Thoroughbred mares in central Kentucky.

PubMed

Bosh, K A; Powell, D; Neibergs, J S; Shelton, B; Zent, W

2009-12-01

There have been no studies reporting the impact of reproductive efficiency and mare financial value on economic returns. To explore the economic consequences of differences in reproductive efficiency over time in the Thoroughbred mare. Complete production records for 1176 mares were obtained. Production history and drift in foaling date were calculated. Multiple logistic regression was used to identify factors influencing the probability of producing a registered foal in 2005. The 'net present value' and 'internal rate of return' were calculated for economic scenarios involving different initial mare financial values, levels of reproductive efficiency, and durations of investment. Among mares that did not produce a foal every year (63%), the mean time before failing to produce a registered foal was 3.4 years. The majority of mares drifted later in their foaling dates in subsequent foaling seasons. Increasing mare age, foaling after 1st April, needing to be mated multiple times during the season, and producing a lower number of foals in continuous sequence during previous years decreased the probability of producing a registered foal. Over a 7 year investment period, live foals must be produced in all but one year to yield a positive financial return. Profitability was highest among mares of greatest financial value. Mares are long-term investments due to the extended period before there is a return on the investment. Improving our understanding of mare, stallion and management factors that affect the likelihood of producing a live foal are critical to ensuring a positive financial return. Additional work is needed to test the robustness of the study's conclusions when the cost and revenue assumptions are varied. This information can assist in assessing mare profitability and developing management strategies to maximise profitability.

Repeatability and genotypic correlations of reproductive and productive traits of crossbred beef cattle dams.

PubMed

Silva, L N; Gasparino, E; Torres Júnior, R A A; Euclides Filho, K; Silva, L O C; Alencar, M M; Souza Júnior, M D; Battistelli, J V F; Silva, S C C

2015-05-22

Beef cattle production requires reproductive efficiency. However, measures of reproductive traits are not usually collected; consequently, correlated traits that could be used as indicators would be useful. We examined associations between measures of reproductive and productive efficiency that could be used as selection indicators. Data from 194 dams of the genetic groups Angus x Nelore, Caracu x Nelore, and Valdostana x Nelore collected over 4 years were used. The reproductive traits analyzed were days to heat (DH), calving interval (CI), days to calving (DC), and pregnancy rate (PR). The productive traits were dam weight (DW), body condition score (BCS), calf weight (CW), and weaning rate (WR). The effects on the model were: year, genetic group, reproductive status (RS), age, reproductive rest, and breed of bull (CW and WR). Multivariate analyses were performed, using the Bayesian approach via Gibbs sampling. We conclude that the reproductive measures are ineffective as selection indicators, whereas using dam weight may be a good alternative.

Saving and Reproduction of Human Motion Data by Using Haptic Devices with Different Configurations

NASA Astrophysics Data System (ADS)

Tsunashima, Noboru; Yokokura, Yuki; Katsura, Seiichiro

Recently, there has been increased focus on “haptic recording” development of a motion-copying system is an efficient method for the realization of haptic recording. Haptic recording involves saving and reproduction of human motion data on the basis of haptic information. To increase the number of applications of the motion-copying system in various fields, it is necessary to reproduce human motion data by using haptic devices with different configurations. In this study, a method for the above-mentioned haptic recording is developed. In this method, human motion data are saved and reproduced on the basis of work space information, which is obtained by coordinate transformation of motor space information. The validity of the proposed method is demonstrated by experiments. With the proposed method, saving and reproduction of human motion data by using various devices is achieved. Furthermore, it is also possible to use haptic recording in various fields.

Morphological and physiological changes during reproduction and their relationships to reproductive performance in a capital breeder.

PubMed

Stahlschmidt, Zachary R; Lourdais, Olivier; Lorioux, Sophie; Butler, Michael W; Davis, Jon R; Salin, Karine; Voituron, Yann; DeNardo, Dale F

2013-01-01

Current reproductive effort typically comes at a cost to future reproductive value by altering somatic function (e.g., growth or self-maintenance). Furthermore, effects of reproduction often depend on both fecundity and stage of reproduction, wherein allocation of resources into additional offspring and/or stages of reproduction results in increased costs. Despite these widely accepted generalities, interindividual variation in the effects of reproduction is common-yet the proximate basis that allows some individuals to mitigate these detrimental effects is unclear. We serially measured several variables of morphology (e.g., musculature) and physiology (e.g., antioxidant defenses) in female Children's pythons (Antaresia childreni) throughout reproduction to examine how these traits change over the course of reproduction and whether certain physiological traits are associated with reduced effects of reproduction in some individuals. Reproduction in this capital breeder was associated with changes in both morphology and physiology, but only morphological changes varied with fecundity and among specific reproductive stages. During reproduction, we detected negative relationships between morphology and self-maintenance (e.g., increased muscle allocation to reproduction was related to reduced immune function). Additionally, females that allocated resources more heavily into current reproduction also did so during future reproduction, and these females assimilated resources more efficiently, experienced reduced detriments to self-maintenance (e.g., lower levels of oxidative damage and glucocorticoids) during reproduction, and produced clutches with greater hatching success. Our results suggest that interindividual variation in specific aspects of physiology (assimilation efficiency and oxidative status) may drive variation in reproductive performance.

Sampling efficiency of the Moore egg collector

USGS Publications Warehouse

Worthington, Thomas A.; Brewer, Shannon K.; Grabowski, Timothy B.; Mueller, Julia

2013-01-01

Quantitative studies focusing on the collection of semibuoyant fish eggs, which are associated with a pelagic broadcast-spawning reproductive strategy, are often conducted to evaluate reproductive success. Many of the fishes in this reproductive guild have suffered significant reductions in range and abundance. However, the efficiency of the sampling gear used to evaluate reproduction is often unknown and renders interpretation of the data from these studies difficult. Our objective was to assess the efficiency of a modified Moore egg collector (MEC) using field and laboratory trials. Gear efficiency was assessed by releasing a known quantity of gellan beads with a specific gravity similar to that of eggs from representatives of this reproductive guild (e.g., the Arkansas River Shiner Notropis girardi) into an outdoor flume and recording recaptures. We also used field trials to determine how discharge and release location influenced gear efficiency given current methodological approaches. The flume trials indicated that gear efficiency ranged between 0.0% and 9.5% (n = 57) in a simple 1.83-m-wide channel and was positively related to discharge. Efficiency in the field trials was lower, ranging between 0.0% and 3.6%, and was negatively related to bead release distance from the MEC and discharge. The flume trials indicated that the gellan beads were not distributed uniformly across the channel, although aggregation was reduced at higher discharges. This clustering of passively drifting particles should be considered when selecting placement sites for an MEC; further, the use of multiple devices may be warranted in channels with multiple areas of concentrated flow.

Beadex Function in the Motor Neurons Is Essential for Female Reproduction in Drosophila melanogaster

PubMed Central

Kairamkonda, Subhash; Nongthomba, Upendra

2014-01-01

Drosophila melanogaster has served as an excellent model system for understanding the neuronal circuits and molecular mechanisms regulating complex behaviors. The Drosophila female reproductive circuits, in particular, are well studied and can be used as a tool to understand the role of novel genes in neuronal function in general and female reproduction in particular. In the present study, the role of Beadex, a transcription co-activator, in Drosophila female reproduction was assessed by generation of mutant and knock down studies. Null allele of Beadex was generated by transposase induced excision of P-element present within an intron of Beadex gene. The mutant showed highly compromised reproductive abilities as evaluated by reduced fecundity and fertility, abnormal oviposition and more importantly, the failure of sperm release from storage organs. However, no defect was found in the overall ovariole development. Tissue specific, targeted knock down of Beadex indicated that its function in neurons is important for efficient female reproduction, since its neuronal knock down led to compromised female reproductive abilities, similar to Beadex null females. Further, different neuronal class specific knock down studies revealed that Beadex function is required in motor neurons for normal fecundity and fertility of females. Thus, the present study attributes a novel and essential role for Beadex in female reproduction through neurons. PMID:25396431

A review of swine genome-wide association studies at USMARC

USDA-ARS?s Scientific Manuscript database

Reproductive efficiency has a great effect on the economic success of pork production. Traits including age at puberty (AP), ovulation rate, number born alive (NBA), and average piglet birth weight (ABW) contribute greatly to reproductive efficiency. To better understand the underlying genetics of r...

Supply and Demand of Energy in the Oocyte and the Role of Mitochondria.

PubMed

Martin, Wilding

2017-01-01

The sole purpose of any mammalian oocyte is to combine with a spermatozoon and form a viable embryo that implants into the uterus and forms a viable foetus. Most of the structures and mechanisms for this reside within the oocyte itself. The sperm limits itself to fertilisation of the oocyte; apart from this, its only contribution is the male genome and the centrosome, required for cell division. Both intrinsic and extrinsic factors determine the formation of a viable embryo. However, the fundamental necessity for successful reproduction resides within the capacity for the developing embryo to generate sufficient levels of energy for optimal development to occur. Energy is generated principally within mitochondria. In this chapter, we discuss some of the fundamental processes of preimplantation embryo development and the role of mitochondria in providing sufficient energy for the successful completion of these processes. We discuss mitochondrial genetics, replication and energy production. Ageing appears to affect the capacity of the mitochondrion to produce sufficient energy to balance the requirements of the embryo. We discuss some of the theories of the effect of maternal age on mitochondrial physiology and the role this plays in reproduction. We propose that maternal age has longer-term effects on individuals than simply on the efficiency of reproduction. We also discuss some of the procedures assisted reproduction has proposed to alleviate the effect of maternal age on reproduction.

Genome-wide association study of swine farrowing traits. Part II: Bayesian analysis of marker data

USDA-ARS?s Scientific Manuscript database

Reproductive efficiency has a great impact on the economic success of pork production. Number born alive (NBA) and average piglet birth weight (ABW) contribute greatly to reproductive efficiency. To better understand the underlying genetics of birth traits, a genome wide association study (GWAS) w...

CONTROL OF REPRODUCTION

USDA-ARS?s Scientific Manuscript database

Control of reproduction is important for seed stock production, selective breeding, growth rate, feed efficiency, meat quality, and biosecurity. These needs to control reproduction differ among cultivars and even segments of the same industry. No matter the impetus for aquaculturists to want to alte...

TRIENNIAL LACTATION SYMPOSIUM: Systems biology of regulatory mechanisms of nutrient metabolism in lactation.

PubMed

McNamara, J P

2015-12-01

A major role of the dairy cow is to convert low-quality plant materials into high-quality protein and other nutrients for humans. We must select and manage cows with the goal of having animals of the greatest efficiency matched to their environment. We have increased efficiency tremendously over the years, yet the variation in productive and reproductive efficiency among animals is still large. In part, this is because of a lack of full integration of genetic, nutritional, and reproductive biology into management decisions. However, integration across these disciplines is increasing as the biological research findings show specific control points at which genetics, nutrition, and reproduction interact. An ordered systems biology approach that focuses on why and how cells regulate energy and N use and on how and why organs interact through endocrine and neurocrine mechanisms will speed improvements in efficiency. More sophisticated dairy managers will demand better information to improve the efficiency of their animals. Using genetic improvement and animal management to improve milk productive and reproductive efficiency requires a deeper understanding of metabolic processes throughout the life cycle. Using existing metabolic models, we can design experiments specifically to integrate data from global transcriptional profiling into models that describe nutrient use in farm animals. A systems modeling approach can help focus our research to make faster and larger advances in efficiency and determine how this knowledge can be applied on the farms.

Assessment of wastewater treatment plant effluent on fish reproduction utilizing the adverse outcome pathway conceptual framework

EPA Science Inventory

Wastewater treatment plant (WWTP) effluents are a known contributor of chemical mixture inputs into the environment. Whole effluent testing guidelines were developed to screen these complex mixtures for acute toxicity. However, efficient and cost-effective approaches for screenin...

Inflorescences of alpine cushion plants freeze autonomously and may survive subzero temperatures by supercooling

PubMed Central

Hacker, Jürgen; Ladinig, Ursula; Wagner, Johanna; Neuner, Gilbert

2011-01-01

Freezing patterns in the high alpine cushion plants Saxifraga bryoides, Saxifraga caesia, Saxifraga moschata and Silene acaulis were studied by infrared thermography at three reproductive stages (bud, anthesis, fruit development). The single reproductive shoots of a cushion froze independently in all four species at every reproductive stage. Ice formation caused lethal damage to the respective inflorescence. After ice nucleation, which occurred mainly in the stalk or the base of the reproductive shoot, ice propagated throughout that entire shoot, but not into neighboring shoots. However, anatomical ice barriers within cushions were not detected. The naturally occurring temperature gradient within the cushion appeared to interrupt ice propagation thermally. Consequently, every reproductive shoot needed an autonomous ice nucleation event to initiate freezing. Ice nucleation was not only influenced by minimum temperatures but also by the duration of exposure. At moderate subzero exposure temperatures (−4.3 to −7.7 °C) the number of frozen inflorescences increased exponentially. Due to efficient supercooling, single reproductive shoots remained unfrozen down to −17.4 °C (cooling rate 6 K h−1). Hence, the observed freezing pattern may be advantageous for frost survival of individual inflorescences and reproductive success of high alpine cushion plants, when during episodic summer frosts damage can be avoided by supercooling. PMID:21151351

Improving smallholder cattle reproductive efficiency in Cambodia to address expanding regional beef demand.

PubMed

Olmo, L; Ashley, K; Young, J R; Suon, S; Thomson, P C; Windsor, P A; Bush, R D

2017-01-01

This study aimed to identify factors associated with cattle reproductive output in rural smallholder farms in Cambodia in order to determine the main causes of reproductive failure and design efficient interventions for improvement. The majority of the nation's beef is produced on smallholder farms where productivity is constrained by poor animal reproductivity reflected in the recent livestock population decline of approximately 13 % from 2009 to 2013. Farmers (n = 240) from 16 villages from five provinces were surveyed in mid-2015 to determine their baseline knowledge, attitude and practices (KAP) associated with cattle reproduction. In addition, 16 case studies from three of these provinces were conducted to provide a more detailed assessment of current cattle reproductive husbandry practices. In order to assess the reproductive impact of previously implemented interventions, an endpoint KAP survey and longitudinal health and husbandry study from three Cambodian provinces conducted between 2008 and 2013 were also analysed. Three multivariable prediction models (two KAP and one longitudinal) identified the following significant factors associated with the reproductive outcomes 'number of calves born' or probability that cows 'gave birth': target feeding (P = 0.074), growing vegetables (P = 0.005), attitudes towards cattle vaccination (P = 0.010), improving bull selection (P = 0.032), local breed use (P = 0.005), number of joining attempts (P < 0.001), discontinuation of animal draught practices (P = 0.003) and retention of breeding animals (P < 0.001). The identification of significant factors and interventions in this study has led to intervention recommendations that can potentially improve reproductive efficiency, combat the declining cattle population and improve smallholder capacity to supply to expanding regional meat demand in South-East Asia and China.

Plasticity in reproduction and growth among 52 range-wide populations of a Mediterranean conifer: adaptive responses to environmental stress.

PubMed

Santos-Del-Blanco, L; Bonser, S P; Valladares, F; Chambel, M R; Climent, J

2013-09-01

A plastic response towards enhanced reproduction is expected in stressful environments, but it is assumed to trade off against vegetative growth and efficiency in the use of available resources deployed in reproduction [reproductive efficiency (RE)]. Evidence supporting this expectation is scarce for plants, particularly for long-lived species. Forest trees such as Mediterranean pines provide ideal models to study the adaptive value of allocation to reproduction vs. vegetative growth given their among-population differentiation for adaptive traits and their remarkable capacity to cope with dry and low-fertility environments. We studied 52 range-wide Pinus halepensis populations planted into two environmentally contrasting sites during their initial reproductive stage. We investigated the effect of site, population and their interaction on vegetative growth, threshold size for female reproduction, reproductive-vegetative size relationships and RE. We quantified correlations among traits and environmental variables to identify allocation trade-offs and ecotypic trends. Genetic variation for plasticity was high for vegetative growth, whereas it was nonsignificant for reproduction. Size-corrected reproduction was enhanced in the more stressful site supporting the expectation for adverse conditions to elicit plastic responses in reproductive allometry. However, RE was unrelated with early reproductive investment. Our results followed theoretical predictions and support that phenotypic plasticity for reproduction is adaptive under stressful environments. Considering expectations of increased drought in the Mediterranean, we hypothesize that phenotypic plasticity together with natural selection on reproductive traits will play a relevant role in the future adaptation of forest tree species. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

TRIENNIAL REPRODUCTION SYMPOSIUM: Developmental programming of fertility.

PubMed

Reynolds, L P; Vonnahme, K A

2016-07-01

The 2015 Triennial Reproduction Symposium focused on developmental programming of fertility. The topics covered during the morning session included the role of the placenta in programming of fetal growth and development, effects of feeding system and level of feeding during pregnancy on the annual production cycle and lifetime productivity of heifer offspring, effects of litter size and level of socialization postnatally on reproductive performance of pigs, effects of postnatal dietary intake on maturation of the hypothalamic-pituitary-gonadal axis and onset of puberty in heifers, effects of housing systems on growth performance and reproductive efficiency of gilts, and effects of energy balance on sexual differentiation in rodent models. The morning session concluded with presentation of the American Society of Animal Science L. E. Casida Award for Excellence in Graduate Education to Dr. Michael Smith from the University of Missouri, Columbia, who shared his philosophy of graduate education. The afternoon session included talks on the role of epigenetic modifications in developmental programming and transgenerational inheritance of reproductive dysfunction, effects of endocrine disrupting compounds on fetal development and long-term physiology of the individual, and potential consequences of real-life exposure to environmental contaminants on reproductive health. The symposium concluded with a summary talk and the posing of 2 questions to the audience. From an evolutionary standpoint, programming and epigenetic events must be adaptive; when do they become maladaptive? If there are so many environmental factors that induce developmental programming, are we doomed, and if not, what is or are the solution or solutions?

[Benefits of nursing care service in the assisted reproduction clinic to self-cycle-management and self-efficiency of infertility patients].

PubMed

Li, Xiao-Qin; Sun, Chao-Feng; Guo, Mei

2017-06-01

To investigate the benefits of nursing care service in the assisted reproduction clinic to self-cycle-management and self-efficiency of the outpatients with infertility. We randomly divided 600 females preliminarily diagnosed with infertility into a control and an experimental group, 288 in the former and 285 in the latter group excluding those whose husbands had azoospermia. For the women patients of the experimental group, we conducted nursing care intervention concerning related knowledge, skills, diet, excise, medication, and psychology, by one-to-one consultation, individualized or group communication, establishing files, telephone follow-up, and wechat guidance. After 3 months of intervention, we compared the compliance of medical visits, effectiveness of cycle management, sense of self-efficiency, satisfaction, and anxiety score between the two groups of patients. In comparison with the controls, the patients of the experimental group showed significantly better knowledge about assisted reproduction and higher effectiveness of self-cycle-management, self-efficiency, and satisfaction (P <0.05), but a markedly lower degree of anxiety (P <0.05). Nursing care service in the assisted reproduction clinic can improve the compliance of medical visits, effectiveness of self-cycle-management, self-efficiency, and satisfaction and reduce the anxiety of the patients.

Masting promotes individual- and population-level reproduction by increasing pollination efficiency.

PubMed

Moreira, Xoaquín; Abdala-Roberts, Luis; Linhart, Yan B; Mooney, Kailen A

2014-04-01

Masting is a reproductive strategy defined as the intermittent and synchronized production of large seed crops by a plant population. The pollination efficiency hypothesis proposes that masting increases pollination success in plants. Despite its general appeal, no previous studies have used long-term data together with population- and individual-level analyses to assess pollination efficiency between mast and non-mast events. Here we rigorously tested the pollination efficiency hypothesis in ponderosa pine (Pinus ponderosa), a long-lived monoecious, wind-pollinated species, using a data set on 217 trees monitored annually for 20 years. Relative investment in male and female function by individual trees did not vary between mast and non-mast years. At both the population and individual level, the rate of production of mature female cones relative to male strobili production was higher in mast than non-mast years, consistent with the predicted benefit of reproductive synchrony on reproductive success. In addition, at the individual level we found a higher conversion of unfertilized female conelets into mature female cones during a mast year compared to a non-mast year. Collectively, parallel results at the population and individual tree level provide robust evidence for the ecological, and potentially also evolutionary, benefits of masting through increased pollination efficiency.

Reproduction reduces photosynthetic capacity in females of the subdioecious Honckenya peploides

NASA Astrophysics Data System (ADS)

Sánchez-Vilas, Julia; Retuerto, Rubén

2011-03-01

As a consequence of the different reproductive functions performed by the sexes, sexually dimorphic/polymorphic plants may exhibit gender-related variations in the energy and resources allocated to reproduction, and in the physiological processes that underlie these differences. This study investigated whether the sexes of the subdioecious plant Honckenya peploides differ in ecophysiological traits related to photosynthetic capacity and whether possible differences depend on reproductive status and on the plant's position (edge or centre) in the population. We registered in three sites in NW Spain, the sex and density of shoots of two segregated clumps of plants. These clumps represent an extreme case of sex-ratio variation across space, with separated single-sex clumps of plants. In two of these sites we measured photosynthetic efficiencies, chlorophyll content, and specific leaf areas. In females, reproduction reduced photochemical efficiency, chlorophyll content and increased the specific leaf area, which is a key leaf trait related to photosynthetic capacity. In males, no differences due to reproduction were detected. The position within the clump affected the specific leaf area of the shoots, with shoots growing at the edge having the lowest values, regardless of the sex. Finally, the effects of position in photosynthetic efficiency and chlorophyll content where highly variable among clumps. We conclude that the differential effects of reproduction on sexes may entail different costs that could be crucial in the outcome of interactions between them, contributing to their spatial segregation.

Complete method to obtain, culture, and transfer mouse blastocysts nonsurgically to study implantation and development.

PubMed

Moreno-Moya, Juan Manuel; Ramírez, Leslie; Vilella, Felipe; Martínez, Sebastián; Quiñonero, Alicia; Noguera, Inmaculada; Pellicer, Antonio; Simón, Carlos

2014-03-01

To illustrate an efficient, complete, step-by-step protocol for studying implantation in mice. Video presentation of an animal model for research in reproductive biology. Mouse (Mus musculus). A nonsurgical embryo transfer system very similar to that used for human embryo transfer. The protocols with recipient and donor mice are performed in parallel in the same week. For the donor mice: the first step is ovarian stimulation, followed by ovulation induction and mating; finally, the mice are sacrificed, and the embryos are collected and cultured. For recipient mice: first estrous synchrony is induced, followed by mating with a vasectomized male, visualization of the vaginal plug, and nonsurgical transfer of the embryos. Finally (optionally), the implantation sites can be visualized on day 7.5 of development. (All animal experiments were performed with the approval of the institutional review board.) Implantation is an essential step in human reproduction although, because of technical and ethics considerations, still relatively little is known about human implantation and early development. Conversely, mouse models are well established and can be used for preliminary experiments. However, there are various bottlenecks in the procedure for obtaining and transferring murine embryos, which makes experimentation with this model more difficult. These difficulties include pseudopregnancy, ovarian hyperstimulation, and embryo collection, culture, and transfer. We have proposed a complete, efficient method for obtaining, culturing, and transferring mouse blastocysts that can be easily applied in research. Potential applications include testing new media components that do not affect preimplantation but do affect implantation and early development. The embryo transfer method proposed here has been demonstrated to achieve embryo implantation easier and faster than, and in approximately similar rates as other traditional surgery methods. This workflow is the first set of complete step-by-step instructions available that incorporate advances such as nonsurgical mouse embryo transfer. This will facilitate research into different reproduction events such as embryo development, embryo implantation, or contraception. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Cyclical parthenogenesis algorithm for layout optimization of truss structures with frequency constraints

NASA Astrophysics Data System (ADS)

Kaveh, A.; Zolghadr, A.

2017-08-01

Structural optimization with frequency constraints is seen as a challenging problem because it is associated with highly nonlinear, discontinuous and non-convex search spaces consisting of several local optima. Therefore, competent optimization algorithms are essential for addressing these problems. In this article, a newly developed metaheuristic method called the cyclical parthenogenesis algorithm (CPA) is used for layout optimization of truss structures subjected to frequency constraints. CPA is a nature-inspired, population-based metaheuristic algorithm, which imitates the reproductive and social behaviour of some animal species such as aphids, which alternate between sexual and asexual reproduction. The efficiency of the CPA is validated using four numerical examples.

Reproductive medicine involving genome editing: clinical uncertainties and embryological needs.

PubMed

Ishii, Tetsuya

2017-01-01

Genome editing based on site-directed nucleases facilitated efficient and versatile genetic modifications in human cells. However, recent reports, demonstrating CRISPR/Cas9-mediated genome editing in human embryos have raised profound concerns worldwide. This commentary explores the clinical justification and feasibility of reproductive medicine using germline genome editing. Despite the perceived utility of reproductive medicine for treating intractable infertility, it is difficult to justify germline genome editing from the perspective of the prospective child. As suggested by the UK legalization regarding mitochondrial donation, the prevention of genetic disease in offspring by genome editing might be acceptable in limited cases of serious or life-threatening conditions, where no alternative medicine is available. Nonetheless, the mosaicism underlying human embryos as well as the off-target effect by artificial nucleases will likely hamper preimplantation genetic diagnosis prior to embryo transfer. Such considerations suggest that this type of reproductive medicine should not be developed toward a clinical application. However, the clinical uncertainties underscore the need for embryology that can address fundamental questions regarding germline aneuploidy and mosaicism using genome editing. Copyright © 2016 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Modelling impacts of performance on the probability of reproducing, and thereby on productive lifespan, allow prediction of lifetime efficiency in dairy cows.

PubMed

Phuong, H N; Blavy, P; Martin, O; Schmidely, P; Friggens, N C

2016-01-01

Reproductive success is a key component of lifetime efficiency - which is the ratio of energy in milk (MJ) to energy intake (MJ) over the lifespan, of cows. At the animal level, breeding and feeding management can substantially impact milk yield, body condition and energy balance of cows, which are known as major contributors to reproductive failure in dairy cattle. This study extended an existing lifetime performance model to incorporate the impacts that performance changes due to changing breeding and feeding strategies have on the probability of reproducing and thereby on the productive lifespan, and thus allow the prediction of a cow's lifetime efficiency. The model is dynamic and stochastic, with an individual cow being the unit modelled and one day being the unit of time. To evaluate the model, data from a French study including Holstein and Normande cows fed high-concentrate diets and data from a Scottish study including Holstein cows selected for high and average genetic merit for fat plus protein that were fed high- v. low-concentrate diets were used. Generally, the model consistently simulated productive and reproductive performance of various genotypes of cows across feeding systems. In the French data, the model adequately simulated the reproductive performance of Holsteins but significantly under-predicted that of Normande cows. In the Scottish data, conception to first service was comparably simulated, whereas interval traits were slightly under-predicted. Selection for greater milk production impaired the reproductive performance and lifespan but not lifetime efficiency. The definition of lifetime efficiency used in this model did not include associated costs or herd-level effects. Further works should include such economic indicators to allow more accurate simulation of lifetime profitability in different production scenarios.

RFamide-related peptide 3 and gonadotropin-releasing hormone-II are autocrine-paracrine regulators of testicular function in the boar

USDA-ARS?s Scientific Manuscript database

Widespread use of artificial insemination in swine requires millions of doses of boar semen each year. Subfertility of boars remains a major constraint, which can impact the reproductive efficiency of thousands of sows, so a better understanding of testicular function is needed in order to develop m...

Exploiting rRNA operon copy number to investigate bacterial reproductive strategies.

PubMed

Roller, Benjamin R K; Stoddard, Steven F; Schmidt, Thomas M

2016-09-12

The potential for rapid reproduction is a hallmark of microbial life, but microbes in nature must also survive and compete when growth is constrained by resource availability. Successful reproduction requires different strategies when resources are scarce and when they are abundant 1,2 , but a systematic framework for predicting these reproductive strategies in bacteria has not been available. Here, we show that the number of ribosomal RNA operons (rrn) in bacterial genomes predicts two important components of reproduction-growth rate and growth efficiency-which are favoured under contrasting regimes of resource availability 3,4 . We find that the maximum reproductive rate of bacteria doubles with a doubling of rrn copy number, and the efficiency of carbon use is inversely related to maximal growth rate and rrn copy number. We also identify a feasible explanation for these patterns: the rate and yield of protein synthesis mirror the overall pattern in maximum growth rate and growth efficiency. Furthermore, comparative analysis of genomes from 1,167 bacterial species reveals that rrn copy number predicts traits associated with resource availability, including chemotaxis and genome streamlining. Genome-wide patterns of orthologous gene content covary with rrn copy number, suggesting convergent evolution in response to resource availability. Our findings imply that basic cellular processes adapt in contrasting ways to long-term differences in resource availability. They also establish a basis for predicting changes in bacterial community composition in response to resource perturbations using rrn copy number measurements 5 or inferences 6,7 .

Within-Plant Distribution of Adult Brown Stink Bug (Hemiptera: Pentatomidae) in Corn and Its Implications on Stink Bug Sampling and Management in Corn.

PubMed

Babu, Arun; Reisig, Dominic D

2018-05-29

Brown stink bug, Euschistus servus (Say) (Hemiptera: Pentatomidae), has emerged as a significant pest of corn, Zea mays L., in the southeastern United States. A 2-year study was conducted to quantify the within-plant vertical distribution of adult E. servus in field corn, to examine potential plant phenological characteristics associated with their observed distribution, and to select an efficient partial plant sampling method for adult E. servus population estimation. Within-plant distribution of adult E. servus was influenced by corn phenology. On V4- and V6-stage corn, most of the individuals were found at the base of the plant. Mean relative vertical position of adult E. servus population in corn plants trended upward between the V6 and V14 growth stages. During the reproductive corn growth stages (R1, R2, and R4), a majority of the adult E. servus were concentrated around developing ears. Based on the multiple selection criteria, during V4-V6 corn growth stages, either the corn stalk below the lowest green leaf or basal stratum method could employ for efficient E. servus sampling. Similarly, on reproductive corn growth stages (R1-R4), the plant parts between two leaves above and three leaves below the primary ear leaf were found to be areas to provide the most precise and cost-efficient sampling method. The results from our study successfully demonstrate that in the early vegetative and reproductive stages of corn, scouts can replace the current labor-intensive whole-plant search method with a more efficient, specific partial plant sampling method for E. servus population estimation.

Linking pollinator efficiency to patterns of pollen limitation: small bees exploit the plant-pollinator mutualism.

PubMed

Koski, Matthew H; Ison, Jennifer L; Padilla, Ashley; Pham, Angela Q; Galloway, Laura F

2018-06-13

Seemingly mutualistic relationships can be exploited, in some cases reducing fitness of the exploited species. In plants, the insufficient receipt of pollen limits reproduction. While infrequent pollination commonly underlies pollen limitation (PL), frequent interactions with low-efficiency, exploitative pollinators may also cause PL. In the widespread protandrous herb Campanula americana , visitation by three pollinators explained 63% of the variation in PL among populations spanning the range. Bumblebees and the medium-sized Megachile campanulae enhanced reproductive success, but small solitary bees exacerbated PL. To dissect mechanisms behind these relationships, we scored sex-specific floral visitation, and the contributions of each pollinator to plant fitness using single flower visits. Small bees and M. campanulae overvisited male-phase flowers, but bumblebees frequently visited female-phase flowers. Fewer bumblebee visits were required to saturate seed set compared to other bees. Scaling pollinator efficiency metrics to populations, small bees deplete large amounts of pollen due to highly male-biased flower visitation and infrequent pollen deposition. Thus, small bees reduce plant reproduction by limiting pollen available for transfer by efficient pollinators, and appear to exploit the plant-pollinator mutualism, acting as functional parasites to C. americana It is therefore unlikely that small bees will compensate for reproductive failure in C. americana when bumblebees are scarce. © 2018 The Author(s).

Gender and social reproduction: historical perspectives.

PubMed

Laslett, B; Brenner, J

1989-01-01

It is argued that gender relations and social reproduction were both shaped by macrohistorical processes and shaped the processes. Social reproduction is defined within feminist theory as more than production in the Marxist sense. Societal reproduction is a combination of the organization of production, the organization of social reproduction, the perpetuation of gender, and the continuation of class relations. Social reproduction includes the care and socialization of children and care of the elderly or infirm. Social reproduction includes the organization of sexuality, biological reproduction, and how food, clothing, and shelter are made available. Most social reproduction occurs within the family unit. It is pointed out that variations in the distribution of the work of social reproduction are affected by the family, market, community, and state. The ways in which women construct their own worlds of activity is a central concern. The feminist concept of social reproduction differs from modernization theory, which is concerned with the institutional location of the tasks of social reproduction and the structural effects on the family and gender relations. This literature review focuses only on the history of family strategies and separate gender-related activities. The authors describe the changes in family organization that define men as income producers and women as caretakers, who base child rearing on love and feminine virtue rather than patriarchal authority and religious doctrine. The discussion focuses on the differences in marital relationships, motherhood, and sexuality between upper and middle class and working class women in the 19th century. Among working class women, a good wife was an efficient manager, a skilled domestic worker, and an income earner. The turn of the century was a period of social change marked by smaller average family size, the decline of household production, the rise in real wages, and increased consumption. It is argued that new developments in gender relations are due to sex as well as economics and the institutionalization of these changes results in constraints and opportunities for women.

Reproductive rights approach to reproductive health in developing countries.

PubMed

Pillai, Vijayan K; Gupta, Rashmi

2011-01-01

Research on reproductive health in developing countries focuses mostly on the role of economic development on various components of reproductive health. Cross-sectional and empirical research studies in particular on the effects of non-economic factors such as reproductive rights remain few and far between. This study investigates the influence of two components of an empowerment strategy, gender equality, and reproductive rights on women's reproductive health in developing countries. The empowerment strategy for improving reproductive health is theoretically situated on a number of background factors such as economic and social development. Cross-national socioeconomic and demographic data from a number of international organizations on 142 developing countries are used to test a model of reproductive rights and reproductive health. The findings suggest that both economic and democratic development have significant positive effects on levels of gender equality. The level of social development plays a prominent role in promoting reproductive rights. It is found that reproductive rights channel the influences of social structural factors and gender equality on reproductive health.

Reproductive traits affect the rescue of valuable and endangered multipurpose tropical trees

PubMed Central

Sinébou, Viviane; Quinet, Muriel; Ahohuendo, Bonaventure C.; Jacquemart, Anne-Laure

2016-01-01

Conservation strategies are urgently needed in Tropical areas for widely used tree species. Increasing numbers of species are threatened by overexploitation and their recovery might be poor due to low reproductive success and poor regeneration rates. One of the first steps in developing any conservation policy should be an assessment of the reproductive biology of species that are threatened by overexploitation. This work aimed to study the flowering biology, pollination and breeding system of V. doniana, a multipurpose threatened African tree, as one step in assessing the development of successful conservation strategies. To this end, we studied (1) traits directly involved in pollinator attraction like flowering phenology, flower numbers and morphology, and floral rewards; (2) abundance, diversity and efficiency of flower visitors; (3) breeding system, through controlled hand-pollination experiments involving exclusion of pollinators and pollen from different sources; and (4) optimal conditions for seed germination. The flowering phenology was asynchronous among inflorescences, trees and sites. The flowers produced a large quantity of pollen and nectar with high sugar content. Flowers attracted diverse and abundant visitors, counting both insects and birds, and efficient pollinators included several Hymenoptera species. We detected no spontaneous self-pollination, indicating a total dependence on pollen vectors. Vitex doniana is self-compatible and no inbreeding depression occurred in the first developmental stages. After extraction of the seed from the fruit, seed germination did not require any particular conditions or pre-treatments and the seeds showed high germination rates. These pollination and breeding characteristics as well as germination potential offer the required conditions to develop successful conservation strategies. Protection, cultivation and integration in agroforestry systems are required to improve the regeneration of the tree. PMID:27354660

Reproductive traits affect the rescue of valuable and endangered multipurpose tropical trees.

PubMed

Sinébou, Viviane; Quinet, Muriel; Ahohuendo, Bonaventure C; Jacquemart, Anne-Laure

2016-01-01

Conservation strategies are urgently needed in Tropical areas for widely used tree species. Increasing numbers of species are threatened by overexploitation and their recovery might be poor due to low reproductive success and poor regeneration rates. One of the first steps in developing any conservation policy should be an assessment of the reproductive biology of species that are threatened by overexploitation. This work aimed to study the flowering biology, pollination and breeding system of V. doniana, a multipurpose threatened African tree, as one step in assessing the development of successful conservation strategies. To this end, we studied (1) traits directly involved in pollinator attraction like flowering phenology, flower numbers and morphology, and floral rewards; (2) abundance, diversity and efficiency of flower visitors; (3) breeding system, through controlled hand-pollination experiments involving exclusion of pollinators and pollen from different sources; and (4) optimal conditions for seed germination. The flowering phenology was asynchronous among inflorescences, trees and sites. The flowers produced a large quantity of pollen and nectar with high sugar content. Flowers attracted diverse and abundant visitors, counting both insects and birds, and efficient pollinators included several Hymenoptera species. We detected no spontaneous self-pollination, indicating a total dependence on pollen vectors. Vitex doniana is self-compatible and no inbreeding depression occurred in the first developmental stages. After extraction of the seed from the fruit, seed germination did not require any particular conditions or pre-treatments and the seeds showed high germination rates. These pollination and breeding characteristics as well as germination potential offer the required conditions to develop successful conservation strategies. Protection, cultivation and integration in agroforestry systems are required to improve the regeneration of the tree. Published by Oxford University Press on behalf of the Annals of Botany Company.

Unravelling the Costs of Flight for Immune Defenses in the Migratory Monarch Butterfly.

PubMed

Fritzsche McKay, Alexa; Ezenwa, Vanessa O; Altizer, Sonia

2016-08-01

Migratory animals undergo extreme physiological changes to prepare for and sustain energetically costly movements; one potential change is reduced investment in immune defenses. However, because some migrants have evolved to minimize the energetic demands of movement (for example, through the temporary atrophy of non-essential organs such as those involved in reproduction), migratory animals could potentially avoid immunosuppression during long-distance journeys. In this study, we used a tethered flight mill to examine immune consequences of experimentally induced powered flight in eastern North American monarch butterflies. These butterflies undergo an annual two-way long-distance migration each year from as far north as Canada to wintering sites in Central Mexico. We quantified immune measures as a function of categorical flight treatment (flown versus control groups) and continuous measures of flight effort (e.g., flight distance, duration, and measures of efficiency). We also examined whether relationships between flight and immune measures depended on reproductive investment by experimentally controlling whether monarchs were reproductive or in state of reproductive diapause (having atrophied reproductive organs) prior to flight. Of the three immune responses we measured, hemocyte concentration (the number of immune cells) was lower in flown monarchs relative to controls but increased with flight distance among flown monarchs; the other two immune measures showed no relationship to monarch flight. We also found that monarchs that were reproductively active were less efficient fliers, as they exerted more power during flight than monarchs in reproductive diapause. However, reproductive status did not modify relationships between flight and immune measures. Results of this study add to a growing body of work suggesting that migratory monarchs-like some other animals that travel vast distances-can complete their journeys with efficient use of resources and minimal costs. © The Author 2016. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Equilibriumizing all food chain chaos through reproductive efficiency.

PubMed

Deng, Bo

2006-12-01

The intraspecific interference of a top-predator is incorporated into a classical mathematical model for three-trophic food chains. All chaos types known to the classical model are shown to exist for this comprehensive model. It is further demonstrated that if the top-predator reproduces at high efficiency, then all chaotic dynamics will change to a stable coexisting equilibrium, a novel property not found in the classical model. This finding gives a mechanistic explanation to the question of why food chain chaos is rare in the field. It also suggests that high reproductive efficiency of top-predators tends to stabilize food chains.

Effect of different light sources on reproductive anatomy and physiology of Japanese quail (Coturnix coturnix japonica).

PubMed

Bobadilla-Mendez, M F; Rojas-Granados, C P; Andrade, E F; Retes, P L; Ferreira, L G; Alvarenga, R R; Rodriguez-Gil, J E; Fassani, E J; Zangeronimo, M G

2016-05-01

Artificial lights are essential for controlling the reproductive tract development of birds during puberty and therefore influence reproductive quality. The aim of this study was to evaluate the effect of different light sources on reproductive anatomic and physiological characteristics of female Japanese quail (Coturnix coturnix japonica). A total of 270 birds from one day of age were housed in a masonry shed divided into six rooms with light isolation. Each room was equipped with a different type of light bulb and contained seven cages with five birds in each. The light bulbs tested were: incandescent; compact fluorescent; and light-emitting diode (LED) in the colors white, blue, red and green. The experimental design was completely randomized with six treatments and seven replications of individual birds each. The anatomic and physiological condition of the birds was evaluated at four, eight and 12 weeks of age. The white LED bulb advanced (P<0.05) the sexual maturity by one week, resulted (P<0.05) in higher live weights and greater weight and relative percentage of ovarian stroma, oviduct and ovarian tissue at eight weeks of age. Higher plasma concentrations of estradiol and lipids were also observed (P<0.05) at eight weeks under the white LED bulb. At 12 weeks of age, the magnum and isthmus folding characteristics were better (P<0.05) with the red LED bulb. In conclusion, the photostimulation with the white LED bulb was more efficient at activating the reproductive cycle, hastening the onset of sexual maturity and increasing the development of reproductive organs after puberty. Copyright © 2016 Elsevier B.V. All rights reserved.

Reproductive rights approach to reproductive health in developing countries

PubMed Central

Pillai, Vijayan K.; Gupta, Rashmi

2011-01-01

Background Research on reproductive health in developing countries focuses mostly on the role of economic development on various components of reproductive health. Cross-sectional and empirical research studies in particular on the effects of non-economic factors such as reproductive rights remain few and far between. Objective This study investigates the influence of two components of an empowerment strategy, gender equality, and reproductive rights on women's reproductive health in developing countries. The empowerment strategy for improving reproductive health is theoretically situated on a number of background factors such as economic and social development. Design Cross-national socioeconomic and demographic data from a number of international organizations on 142 developing countries are used to test a model of reproductive rights and reproductive health. Results The findings suggest that both economic and democratic development have significant positive effects on levels of gender equality. The level of social development plays a prominent role in promoting reproductive rights. It is found that reproductive rights channel the influences of social structural factors and gender equality on reproductive health. PMID:22184501

Germline replacement by blastula cell transplantation in the fish medaka.

PubMed

Li, Mingyou; Hong, Ni; Xu, Hongyan; Song, Jianxing; Hong, Yunhan

2016-07-13

Primordial germ cell (PGC) specification early in development establishes the germline for reproduction and reproductive technologies. Germline replacement (GR) is a powerful tool for conservation of valuable or endangered animals. GR is achievable by germ cell transplantation into the PGC migration pathway or gonads. Blastula cell transplantation (BCT) can also lead to the chimeric germline containing PGCs of both donor and host origins. It has remained largely unknown whether BCT is able to achieve GR at a high efficiency. Here we report efficient GR by BCT into blastula embryos in the fish medaka (Oryzias latipes). Specifically, dnd depletion completely ablated host PGCs and fertility, and dnd overexpression remarkably boosted PGCs in donor blastulae. BCT between normal donor and host produced a germline transmission rate of ~4%. This rate was enhanced up to ~30% upon PGC boosting in donors. Most importantly, BCT between PGC-boosted donors and PGC-ablated hosts led to more than 90% fertility restoration and 100% GR. Therefore, BCT features an extremely high efficiency of fertility recovery and GR in medaka. This finding makes medaka an ideal model to analyze genetic and physiological donor-host compatibilities for BCT-mediated surrogate production and propagation of endangered lower vertebrates and biodiversity.

Germline replacement by blastula cell transplantation in the fish medaka

PubMed Central

Li, Mingyou; Hong, Ni; Xu, Hongyan; Song, Jianxing; Hong, Yunhan

2016-01-01

Primordial germ cell (PGC) specification early in development establishes the germline for reproduction and reproductive technologies. Germline replacement (GR) is a powerful tool for conservation of valuable or endangered animals. GR is achievable by germ cell transplantation into the PGC migration pathway or gonads. Blastula cell transplantation (BCT) can also lead to the chimeric germline containing PGCs of both donor and host origins. It has remained largely unknown whether BCT is able to achieve GR at a high efficiency. Here we report efficient GR by BCT into blastula embryos in the fish medaka (Oryzias latipes). Specifically, dnd depletion completely ablated host PGCs and fertility, and dnd overexpression remarkably boosted PGCs in donor blastulae. BCT between normal donor and host produced a germline transmission rate of ~4%. This rate was enhanced up to ~30% upon PGC boosting in donors. Most importantly, BCT between PGC-boosted donors and PGC-ablated hosts led to more than 90% fertility restoration and 100% GR. Therefore, BCT features an extremely high efficiency of fertility recovery and GR in medaka. This finding makes medaka an ideal model to analyze genetic and physiological donor-host compatibilities for BCT-mediated surrogate production and propagation of endangered lower vertebrates and biodiversity. PMID:27406328

Lower group productivity under kin-selected reproductive altruism.

PubMed

Teyssèdre, Anne; Couvet, Denis; Nunney, Leonard

2006-10-01

Hamilton's rule provides the foundation for understanding the genetic evolution of social behavior, showing that altruism is favored by increased relatedness and increased productivity of altruists. But how likely is it that a new altruistic mutation will satisfy Hamilton's rule by increasing the reproductive efficiency of the group? Altruism per se does not improve efficiency, and hence we would not expect a typical altruistic mutation to increase the mean productivity of the population. We examined the conditions under which a mutation causing reproductive altruism can spread when it does not increase productivity. We considered a population divided into temporary groups of genetically similar individuals (typically family groups). We show that the spread of altruism requires a pleiotropic link between altruism and enhanced productivity in diploid organisms, but not in haplodiploid organisms such as Hymenoptera. This result provides a novel biological understanding of the barrier to the spread of reproductive altruism in diploids. In haplodiploid organisms, altruism within families that lowers productivity may spread, provided daughters sacrifice their own reproduction to raise full-sisters. We verified our results using three single-locus genetic models that explore a range of the possible reproductive costs of helping. The advantage of female-to-female altruism in haplodiploids is a well-known prediction of Hamilton's rule, but its importance in relaxing the linkage between altruism and efficiency has not been explored. We discuss the possible role of such unproductive altruism in the origins of sociality. We also note that each model predicts a large region of parameter space were polymorphism between altruism and selfishness is maintained, a pattern independent of dominance.

Factors affecting the efficiency of embryo transfer in the domestic ferret (Mustela putorius furo).

PubMed

Li, Ziyi; Sun, Xingshen; Chen, Juan; Leno, Gregory H; Engelhardt, John F

2006-07-15

Embryo transfer (ET) to recipient females is a foundational strategy for a number of assisted reproductive technologies, including cloning by somatic cell nuclear transfer. In an attempt to develop efficient ET in domestic ferrets, factors affecting development of transferred embryo were investigated. Unilateral and bilateral transfer of zygotes or blastocysts in the oviduct or uterus was evaluated in recipient nulliparous or primiparous females. Developing fetuses were collected from recipient animals 21 days post-copulation and examined. The percentage of fetal formation was different (P<0.05) for unilateral and bilateral transfer of zygotes (71%) in nulliparous females with bilateral transfer (56%) in primiparous recipients. The percentage (90%) of fetal formation in nulliparous recipients following unilateral transfer of blastocysts was higher (P<0.05) than that observed in primiparous recipients with bilateral ET (73%). Notably, the percentage of fetal formation was higher (P<0.05) when blastocyts were transferred as compared to zygotes (90% versus 71%). Transuterine migration of embryos occurred following all unilateral transfers and also in approximately 50% of bilateral transfers with different number of embryos in each uterine horn. These data will help to facilitate the development of assisted reproductive strategies in the ferret and could lead to the use of this species for modeling human disease and for conservation of the endangered Mustelidae species such as black-footed ferret and European mink.

Factors affecting the efficiency of embryo transfer in the domestic ferret (Mustela putorius furo)

PubMed Central

Li, Ziyi; Sun, Xingshen; Chen, Juan; Leno, Gregory H.; Engelhardt, John F.

2007-01-01

Embryo transfer (ET) to recipient females is a foundational strategy for a number of assisted reproductive technologies, including cloning by somatic cell nuclear transfer. In an attempt to develop efficient ET in domestic ferrets, factors affecting development of transferred embryo were investigated. Unilateral and bilateral transfer of zygotes or blastocysts in the oviduct or uterus was evaluated in recipient nulliparous or primiparous females. Developing fetuses were collected from recipient animals 21 days post-copulation and examined. The percentage of fetal formation was different (P < 0.05) for unilateral and bilateral transfer of zygotes (71%) in nulliparous females with bilateral transfer (56%) in primiparous recipients. The percentage (90%) of fetal formation in nulliparous recipients following unilateral transfer of blastocysts was higher (P < 0.05) than that observed in primiparous recipients with bilateral ET (73%). Notably, the percentage of fetal formation was higher (P < 0.05) when blastocyts were transferred as compared to zygotes (90% versus 71%). Transuterine migration of embryos occurred following all unilateral transfers and also in approximately 50% of bilateral transfers with different number of embryos in each uterine horn. These data will help to facilitate the development of assisted reproductive strategies in the ferret and could lead to the use of this species for modeling human disease and for conservation of the endangered Mustelidae species such as black-footed ferret and European mink. PMID:16330092

Suppression of injuries caused by a lytic RNA virus (mengovirus) and their uncoupling from viral reproduction by mutual cell/virus disarmament.

PubMed

Mikitas, Olga V; Ivin, Yuri Y; Golyshev, Sergey A; Povarova, Natalia V; Galkina, Svetlana I; Pletjushkina, Olga Y; Nadezhdina, Elena S; Gmyl, Anatoly P; Agol, Vadim I

2012-05-01

Viruses often elicit cell injury (cytopathic effect [CPE]), a major cause of viral diseases. CPE is usually considered to be a prerequisite for and/or consequence of efficient viral growth. Recently, we proposed that viral CPE may largely be due to host defensive and viral antidefensive activities. This study aimed to check the validity of this proposal by using as a model HeLa cells infected with mengovirus (MV). As we showed previously, infection of these cells with wild-type MV resulted in necrosis, whereas a mutant with incapacitated antidefensive ("security") viral leader (L) protein induced apoptosis. Here, we showed that several major morphological and biochemical signs of CPE (e.g., alterations in cellular and nuclear shape, plasma membrane, cytoskeleton, chromatin, and metabolic activity) in cells infected with L(-) mutants in the presence of an apoptosis inhibitor were strongly suppressed or delayed for long after completion of viral reproduction. These facts demonstrate that the efficient reproduction of a lytic virus may not directly require development of at least some pathological alterations normally accompanying infection. They also imply that L protein is involved in the control of many apparently unrelated functions. The results also suggest that the virus-activated program with competing necrotic and apoptotic branches is host encoded, with the choice between apoptosis and necrosis depending on a variety of intrinsic and extrinsic conditions. Implementation of this defensive suicidal program could be uncoupled from the viral reproduction. The possibility of such uncoupling has significant implications for the pathogenesis and treatment of viral diseases.

Suppression of Injuries Caused by a Lytic RNA Virus (Mengovirus) and Their Uncoupling from Viral Reproduction by Mutual Cell/Virus Disarmament

PubMed Central

Mikitas, Olga V.; Ivin, Yuri Y.; Golyshev, Sergey A.; Povarova, Natalia V.; Galkina, Svetlana I.; Pletjushkina, Olga Y.; Nadezhdina, Elena S.; Gmyl, Anatoly P.

2012-01-01

Viruses often elicit cell injury (cytopathic effect [CPE]), a major cause of viral diseases. CPE is usually considered to be a prerequisite for and/or consequence of efficient viral growth. Recently, we proposed that viral CPE may largely be due to host defensive and viral antidefensive activities. This study aimed to check the validity of this proposal by using as a model HeLa cells infected with mengovirus (MV). As we showed previously, infection of these cells with wild-type MV resulted in necrosis, whereas a mutant with incapacitated antidefensive (“security”) viral leader (L) protein induced apoptosis. Here, we showed that several major morphological and biochemical signs of CPE (e.g., alterations in cellular and nuclear shape, plasma membrane, cytoskeleton, chromatin, and metabolic activity) in cells infected with L− mutants in the presence of an apoptosis inhibitor were strongly suppressed or delayed for long after completion of viral reproduction. These facts demonstrate that the efficient reproduction of a lytic virus may not directly require development of at least some pathological alterations normally accompanying infection. They also imply that L protein is involved in the control of many apparently unrelated functions. The results also suggest that the virus-activated program with competing necrotic and apoptotic branches is host encoded, with the choice between apoptosis and necrosis depending on a variety of intrinsic and extrinsic conditions. Implementation of this defensive suicidal program could be uncoupled from the viral reproduction. The possibility of such uncoupling has significant implications for the pathogenesis and treatment of viral diseases. PMID:22438537

Feed efficiency - how should it be used for the cow herd?

USDA-ARS?s Scientific Manuscript database

In cows, the most critical factor influencing the output component of efficiency is reproductive rate, and not necessarily weight gain. Thus benefits of selecting animals with desirable measures of feed efficiency on cow efficiency remain to be determined. The feed input component of cow efficiency...

The dynamics of reproductive rate, offspring survivorship and growth in the lined seahorse, Hippocampus erectus Perry, 1810

PubMed Central

Lin, Qiang; Li, Gang; Qin, Geng; Lin, Junda; Huang, Liangmin; Sun, Hushan; Feng, Peiyong

2012-01-01

Summary Seahorses are the vertebrate group with the embryonic development occurring within a special pouch in males. To understand the reproductive efficiency of the lined seahorse, Hippocampus erectus Perry, 1810 under controlled breeding experiments, we investigated the dynamics of reproductive rate, offspring survivorship and growth over births by the same male seahorses. The mean brood size of the 1-year old pairs in the 1st birth was 85.4±56.9 per brood, which was significantly smaller than that in the 6th birth (465.9±136.4 per brood) (P<0.001). The offspring survivorship and growth rate increased with the births. The fecundity was positively correlated with the length of brood pouches of males and trunk of females. The fecundity of 1-year old male and 2-year old female pairs was significantly higher than that from 1-year old couples (P<0.001). The brood size (552.7±150.4) of the males who mated with females that were isolated for the gamete-preparation, was larger than those (467.8±141.2) from the long-term pairs (P<0.05). Moreover, the offspring from the isolated females had higher survival and growth rates. Our results showed that the potential reproductive rate of seahorses H. erectus increased with the brood pouch development. PMID:23213429

Using UHF proximity loggers to quantify male-female interactions: a scoping study of estrous activity in cattle.

PubMed

O'Neill, C J; Bishop-Hurley, G J; Williams, P J; Reid, D J; Swain, D L

2014-12-10

Reproductive efficiency is an important determinant of profitable cattle breeding systems and the success of assisted reproductive techniques (ART) in wildlife conservation programs. Methods of estrous detection used in intensive beef and dairy cattle systems lack accuracy and remain the single biggest issue for improvement of reproductive rates and such methods are not practical for either large-scale extensive beef cattle enterprises or free-living mammalian species. Recent developments in UHF (ultra high frequency) proximity logger telemetry devices have been used to provide a continuous pair-wise measure of associations between individual animals for both livestock and wildlife. The objective of this study was to explore the potential of using UHF telemetry to identify the reproductive cycle phenotype in terms of intensity and duration of estrus. The study was conducted using Belmont Red (interbred Africander Brahman Hereford-Shorthorn) cattle grazing irrigated pasture on Belmont Research Station, northeastern Australia. The cow-bull associations from three groups of cows each with one bull were recorded over a 7-week breeding season and the stage of estrus was identified using ultrasonography. Telemetry data from bull and cows, collected over 4 8-day logger deployments, were log transformed and analyzed by ANOVA. Both the number and duration of bull-cow affiliations were significantly (P<0.001) greater in estrous cows compared to anestrus cows. These results support the development of the UHF technology as a hands-off and noninvasive means of gathering socio-sexual information on both wildlife and livestock for reproductive management. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

Intergenerational and sibling conflict under patrilocality. A model of reproductive skew applied to human kinship.

PubMed

Ji, Ting; Xu, Jing-Jing; Mace, Ruth

2014-03-01

Here we argue that models developed to examine cooperation and conflict in communal breeders, using a "tug-of-war" model of reproductive skew generated by incomplete control, are an appropriate way to model human kinship systems. We apply such models to understand the patterns of effort put into competition between father and son and between brothers in conflict over family resources in a patrilineal kinship system. Co-resident kin do not necessarily emerge with equal shares of the cake in terms of reproductive output. The models show that, depending on the efficiency with which they can gain more control of the resource, on the marriage system, and on the relatedness of the partners in conflict, individuals can do better to help their relatives breed rather than fight each other for the resources needed to reproduce. The models show that when a son's father is still breeding with his mother, sons should not compete for any share of reproduction. However, under polygyny, increased effort is spent on father/son and brother/brother conflict. Fathers will win the majority of reproduction if dominant to sons (in contrast to the finding that daughters-in-law win in conflict over mothers-in-law in patrilocal kinship systems, which has been suggested as explaining the evolution of menopause). Hence who wins in the sharing of reproduction depends not just on which sex disperses but also on the relative competitive ability of all individuals to exploit family resources. Anthropologists have long argued that cultural norms can reduce conflict. These formal evolutionary models help us to quantify the effects of reproductive conflict in families, throwing light on the evolutionary basis not just of patterns of reproductive scheduling, but also human kinship and marriage systems.

Utility of Gene Expression and Ex vivo Steroid Production in a 96 h Assay for Predicting Impacts of Endocrine Active Chemicals on Fish Reproduction.

EPA Science Inventory

Development of efficient test methods that can generate reliable data to inform risk assessment is an on-going challenge in the field of ecotoxicology. In the present study we evaluated whether a 96 h in vivo assay focused on a small number of quantitative real-time polymerase ch...

The role of essential trace elements in embryonic and fetal development in livestock.

PubMed

Hostetler, Chris E; Kincaid, Ron L; Mirando, Mark A

2003-09-01

This review addresses the concept that essential trace minerals play a vital role in many enzymatic and metabolic pathways that are critical for conceptus development during pregnancy in livestock species. The conceptus relies entirely on the maternal system for a sufficient supply of trace minerals and other nutrients needed for normal development. If this supply is inadequate, growth and/or health of the conceptus can be affected adversely, and many of these effects carry over into the neonatal period. Information, accumulated in our laboratory and presented herein, indicates that zinc, copper and manganese are among the trace minerals that have the greatest impact on reproduction. For example, levels of zinc, copper and manganese were several fold greater in the conceptus than in other reproductive tissues, indicating that the conceptus preferentially accumulates these minerals, an action that may be important for conceptus development, growth and survival. Moreover, some recent results indicate that increasing the biological availability of zinc, copper and manganese, by attachment to short peptide chains (i.e., proteinated trace minerals) can enhance reproductive performance of swine. Mineral concentrations in conceptuses from female pigs consuming proteinated trace minerals were greater than those from females that consumed only inorganic mineral salts. Elucidating the mechanisms whereby conceptus development and survival are enhanced by essential trace minerals may lead to development of specific feeding programs to increase the number and health of offspring at parturition, thereby allowing for further improvements in production efficiency in animal agriculture.

A Road Map for 21st Century Genetic Restoration: Gene Pool Enrichment of the Black-Footed Ferret

PubMed Central

Ryder, Oliver A.; Santymire, Rachel M.; Engelhardt, John F.; Novak, Ben J.

2015-01-01

Interspecies somatic cell nuclear transfer (iSCNT) could benefit recovery programs of critically endangered species but must be weighed with the risks of failure. To weigh the risks and benefits, a decision-making process that evaluates progress is needed. Experiments that evaluate the efficiency and efficacy of blastocyst, fetal, and post-parturition development are necessary to determine the success or failure or species-specific iSCNT programs. Here, we use the black-footed ferret (Mustela nigripes) as a case study for evaluating this emerging biomedical technology as a tool for genetic restoration. The black-footed ferret has depleted genetic variation yet genome resource banks contain genetic material of individuals not currently represented in the extant lineage. Thus, genetic restoration of the species is in theory possible and could help reduce the persistent erosion of genetic diversity from drift. Extensive genetic, genomic, and reproductive science tools have previously been developed in black-footed ferrets and would aid in the process of developing an iSCNT protocol for this species. Nonetheless, developing reproductive cloning will require years of experiments and a coordinated effort among recovery partners. The information gained from a well-planned research effort with the goal of genetic restoration via reproductive cloning could establish a 21st century model for evaluating and implementing conservation breeding that would be applicable to other genetically impoverished species. PMID:26304983

A Road Map for 21st Century Genetic Restoration: Gene Pool Enrichment of the Black-Footed Ferret.

PubMed

Wisely, Samantha M; Ryder, Oliver A; Santymire, Rachel M; Engelhardt, John F; Novak, Ben J

2015-01-01

Interspecies somatic cell nuclear transfer (iSCNT) could benefit recovery programs of critically endangered species but must be weighed with the risks of failure. To weigh the risks and benefits, a decision-making process that evaluates progress is needed. Experiments that evaluate the efficiency and efficacy of blastocyst, fetal, and post-parturition development are necessary to determine the success or failure or species-specific iSCNT programs. Here, we use the black-footed ferret (Mustela nigripes) as a case study for evaluating this emerging biomedical technology as a tool for genetic restoration. The black-footed ferret has depleted genetic variation yet genome resource banks contain genetic material of individuals not currently represented in the extant lineage. Thus, genetic restoration of the species is in theory possible and could help reduce the persistent erosion of genetic diversity from drift. Extensive genetic, genomic, and reproductive science tools have previously been developed in black-footed ferrets and would aid in the process of developing an iSCNT protocol for this species. Nonetheless, developing reproductive cloning will require years of experiments and a coordinated effort among recovery partners. The information gained from a well-planned research effort with the goal of genetic restoration via reproductive cloning could establish a 21st century model for evaluating and implementing conservation breeding that would be applicable to other genetically impoverished species. © The American Genetic Association. 2015.

Generation of kisspeptin-responsive GnRH neurons from human pluripotent stem cells.

PubMed

Poliandri, Ariel; Miller, Duncan; Howard, Sasha; Nobles, Muriel; Ruiz-Babot, Gerard; Harmer, Stephen; Tinker, Andrew; McKay, Tristan; Guasti, Leonardo; Dunkel, Leo

2017-05-15

GnRH neurons are fundamental for reproduction in all vertebrates, integrating all reproductive inputs. The inaccessibility of human GnRH-neurons has been a major impediment to studying the central control of reproduction and its disorders. Here, we report the efficient generation of kisspeptin responsive GnRH-secreting neurons by directed differentiation of human Embryonic Stem Cells and induced-Pluripotent Stem Cells derived from a Kallman Syndrome patient and a healthy family member. The protocol involves the generation of intermediate Neural Progenitor Cells (NPCs) through long-term Bone morphogenetic protein 4 inhibition, followed by terminal specification of these NPCs in media containing Fibroblast Growth Factor 8 and a NOTCH inhibitor. The resulting GnRH-expressing and -secreting neurons display a neuroendocrine gene expression pattern and present spontaneous calcium transients that can be stimulated by kisspeptin. These in vitro generated GnRH expressing cells provide a new resource for studying the molecular mechanisms underlying the development and function of GnRH neurons. Copyright © 2017 Elsevier B.V. All rights reserved.

Validation of a spectrophotometer-based method for estimating daily sperm production and deferent duct transit.

PubMed

Froman, D P; Rhoads, D D

2012-10-01

The objectives of the present work were 3-fold. First, a new method for estimating daily sperm production was validated. This method, in turn, was used to evaluate testis output as well as deferent duct throughput. Next, this analytical approach was evaluated in 2 experiments. The first experiment compared left and right reproductive tracts within roosters. The second experiment compared reproductive tract throughput in roosters from low and high sperm mobility lines. Standard curves were constructed from which unknown concentrations of sperm cells and sperm nuclei could be predicted from observed absorbance. In each case, the independent variable was based upon hemacytometer counts, and absorbance was a linear function of concentration. Reproductive tracts were excised, semen recovered from each duct, and the extragonadal sperm reserve determined by multiplying volume by sperm cell concentration. Testicular sperm nuclei were procured by homogenization of a whole testis, overlaying a 20-mL volume of homogenate upon 15% (wt/vol) Accudenz (Accurate Chemical and Scientific Corporation, Westbury, NY), and then washing nuclei by centrifugation through the Accudenz layer. Daily sperm production was determined by dividing the predicted number of sperm nuclei within the homogenate by 4.5 d (i.e., the time sperm with elongated nuclei spend within the testis). Sperm transit through the deferent duct was estimated by dividing the extragonadal reserve by daily sperm production. Neither the efficiency of sperm production (sperm per gram of testicular parenchyma per day) nor deferent duct transit differed between left and right reproductive tracts (P > 0.05). Whereas efficiency of sperm production did not differ (P > 0.05) between low and high sperm mobility lines, deferent duct transit differed between lines (P < 0.001). On average, this process required 2.2 and 1.0 d for low and high lines, respectively. In summary, we developed and then tested a method for quantifying male reproductive tract throughput. This method makes the study of semen production amenable to systems biology.

How maya women respond to changing technology : The effect of helping behavior on initiating reproduction.

PubMed

Kramer, K L; McMillan, G P

1998-06-01

In the mid 1970s labor-saving technology was introduced into a Maya subsistence agricultural community that markedly increased the efficiency with which maize could be ground and water collected. This increased efficiency introduces a possible savings in the time that women allocate to work, which can be reapportioned to child care, food production, domestic work, or leisure. An earlier study suggested that this labor-saving technology had a positive effect in decreasing the age at which these Maya women begin their reproductive careers. Although there is a statistical association between the age at which women bear their first child and the introduction of modern technology, this association does not demonstrate that the decline in age at first birth is causally related to the presence of technology. This paper pursues two objectives to evaluate this potential causal relationship in greater detail. First, a theory relating technological change to the initiation of a reproductive career is briefly developed in order to make qualitative predictions about behavioral changes as a response to changing technology. Second, these predictions are then tested against time allocation data recently collected in this same Maya community.We suggest that both of the conditions necessary to initiate reproduction-fecundity and access to mates-fundamentally depend on the amount of help that a girl provides to her family. Further, the help that a girl provides can be affected by technological changes. Analyses show that when modern technology is available, unmarried young women do not change the time allocated to domestic tasks and child care, and allocate more time to low-energy leisure activities. This lack of perceived benefit to working more and a potential concomitant shift towards a positive energy balance may in part explain why Maya women leave home and initiate reproduction at a younger age after labor-saving technology is introduced.

Natural methods for increasing reproductive efficiency in small ruminants.

PubMed

Martin, G B; Milton, J T B; Davidson, R H; Banchero Hunzicker, G E; Lindsay, D R; Blache, D

2004-07-01

This paper describes three strategies to improve the reproductive performance of small ruminants in ways that lead to "clean, green and ethical" animal production. The first is aimed at control of the timing of reproductive events for which we turn to the socio-sexual inputs of the "male effect" to induce synchronised ovulation in females that would otherwise be anovulatory. The second strategy, "focussed feeding", is based on our knowledge of the responses to nutrition and aims to develop short programs of nutritional supplements that are precisely timed and specifically designed for individual events in the reproductive process, such as gamete production, embryo survival, fetal programming and colostrum production. The third strategy aims to maximise offspring survival by a combination of management, nutrition and genetic selection for behavior (temperament). All of these approaches involve non-pharmacological manipulation of the endogenous control systems of the animals and complement the detailed information from ultrasound that is now becoming available. The use of such clean, green and ethical tools in the management of our animals can be cost-effective, increase productivity and, at the same time, greatly improve the image of meat and milk industries in society and the marketplace.

Changes in gene expression and cellular localization of insulin-like growth factors 1 and 2 in the ovaries during ovary development of the yellowtail, Seriola quinqueradiata.

PubMed

Higuchi, Kentaro; Gen, Koichiro; Izumida, Daisuke; Kazeto, Yukinori; Hotta, Takuro; Takashi, Toshinori; Aono, Hideaki; Soyano, Kiyoshi

2016-06-01

A method of controlling the somatic growth and reproduction of yellowtail fish (Seriola quinqueradiata) is needed in order to establish methods for the efficient aquaculture production of the species. However, little information about the hormonal interactions between somatic growth and reproduction is available for marine teleosts. There is accumulating evidence that insulin-like growth factor (IGF), a major hormone related somatic growth, plays an important role in fish reproduction. As the first step toward understanding the physiological role of IGF in the development of yellowtail ovaries, we characterized the expression and cellular localization of IGF-1 and IGF-2 in the ovary during development. We histologically classified the maturity of two-year-old females with ovaries at various developmental stages into the perinucleolar (Pn), yolk vesicle (Yv), primary yolk (Py), secondary yolk and tertiary yolk (Ty) stages, according to the most advanced type of oocyte present. The IGF-1 gene expression showed constitutively high levels at the different developmental stages, although IGF-1 mRNA levels tended to increase from the Py to the Ty stage with vitellogenesis, reaching maximum levels during the Ty stage. The IGF-2 mRNA levels increased as ovarian development advanced. Using immunohistochemistry methods, immunoreactive IGF-1 was mainly detected in the theca cells of ovarian follicles during late secondary oocyte growth, and in part of the granulosa cells of Ty stage oocytes. IGF-2 immunoreactivity was observed in all granulosa cells in layer in Ty stage oocytes. These results indicate that follicular IGFs may be involved in yellowtail reproduction via autocrine/paracrine mechanisms. Copyright © 2016 Elsevier Inc. All rights reserved.

Timing of transcriptomic and proteomic changes in the bovine placentome after parturition

USDA-ARS?s Scientific Manuscript database

Proper post-partum reproductive performance is important for reproductive efficiency in beef cows, and dystocia decreases post-partum fertility. Crossbred beef cows (n = 1676) were evaluated for lifetime performance based on degree of dystocia at presentation of the first calf. Cows that experience...

Deficiency in clonogenic endometrial mesenchymal stem cells in obese women with reproductive failure--a pilot study.

PubMed

Murakami, Keisuke; Bhandari, Harish; Lucas, Emma S; Takeda, Satoru; Gargett, Caroline E; Quenby, Siobhan; Brosens, Jan J; Tan, Bee K

2013-01-01

The mechanisms of obesity associated reproductive complications remain poorly understood. Endometrial mesenchymal stem-cells are critical for cyclic renewal and uterine function. Recently, W5C5(+) cells, with high clonogenicity, capable of producing endometrial stroma in vivo, have been described. We sought to investigate the abundance and cloning efficiency of W5C5(+) and W5C5(-) endometrial cells in relation to Body Mass Index, age and reproductive outcome. W5C5(+) and W5C5(-) cells were purified from mid-luteal endometrial biopsies (n = 54) by magnetic bead separation and subjected to in vitro colony-forming assays. First trimester pregnancy losses were significantly higher in obese subjects (n = 12) compared to overweight (n = 20) and subjects with normal Body Mass Index (n = 22) (P<0.05, P<0.01, respectively). W5C5(+) cells (%) were significantly lower in obese subjects compared to subjects with normal Body Mass Index (P<0.05). W5C5(+) cloning efficiency was significantly lower in obese subjects compared to overweight and subjects with normal Body Mass Index (P<0.05, respectively). W5C5(-) cloning efficiency was significantly lower in obese subjects compared to subjects with normal Body Mass Index (P<0.05). Body Mass Index was significantly negatively correlated with W5C5(+) cloning efficiency and W5C5(-) cloning efficiency (P<0.01, respectively), and positively correlated with first trimester loss (P<0.01). We found no significant results with age (P>0.05). Our observations suggest that the regenerative capacity and plasticity of the endometrium of obese women is suboptimal, which in turn may account for the increased risk of reproductive complications associated with obesity.

Photosynthesis in developing leaf of juveniles and adults of three Mediterranean species with different growth forms.

PubMed

Chondrogiannis, Christos; Grammatikopoulos, George

2016-12-01

Leaf development is influenced by almost all the prevailing environmental conditions as well as from the conditions at the time of bud formation. Furthermore, the growth form of a plant determines the leaf longevity and subsequently the investment in biomass and the internal structure of the mesophyll. Therefore, photosynthetic traits of a growing leaf, though, partly predetermined, should also acclimate to temporal changes during developmental period. In addition, the age of the plant can affect photosynthesis of the growing leaf, yet, in the majority of studies, the age is associated to the size of the plant. To test if the reproductive status of the plant affects the time kinetics of the photosynthetic capacity of a growing leaf and the relative contribution of the plants' growth form to the whole procedure, field measurements were conducted in juveniles (prereproductive individuals) and adults (fully reproductive individuals) of an evergreen sclerophyllous shrub (Nerium oleander), a semi-deciduous dimorphic shrub (Phlomis fruticosa), and a winter deciduous tree with pre-leafing flowering (Cercis siliquastrum). PSII structural and functional integrity was progressively developed in all species, but already completed, only some days after leaf expansion in P. fruticosa. Developing leaf as well as fully developed leaf in adults of C. siliquastrum showed enhanced relative size of the pool of final PSI electron acceptors. Photosynthetic traits between juveniles and adults of P. fruticosa were similar, though the matured leaf of adults exhibited lower transpiration rates and improved water-use efficiency than that of juveniles. Adults of the evergreen shrub attained higher CO 2 assimilation rate than juveniles in matured leaf which can be attributed to higher electron flow devoted to carboxylation, and lower photorespiration rate. The reproductive phase of the plant seemed to be involved in modifications of the PSII and PSI functions of the deciduous tree, in carboxylation and photorespiration traits of the evergreen shrub, and in water conductance efficiency of the semi-deciduous shrub. However, it is interesting, that regardless of the growth form of the plant and the prospective leaf longevity of the developing leaf, adults need to support flowering outmatch juveniles, in terms of photosynthesis.

Short communication: A reproductive tract scoring system to manage fertility in lactating dairy cows.

PubMed

Young, C D; Schrick, F N; Pohler, K G; Saxton, A M; Di Croce, F A; Roper, D A; Wilkerson, J B; Edwards, J L

2017-07-01

We developed a reproductive tract size and position score (SPS) system as a reproductive management tool to identify lactating dairy cows with decreased fertility. This system, relying solely on transrectal palpation, considers the size (cervical and uterine) and position of the reproductive tract relative to the pelvis. Cows undergoing pre-breeding exams were identified as having reproductive tracts that were small (SPS1), medium (SPS2), or large (SPS3). Cows designated SPS1 had small and compact uterine horns that rested within the pelvic cavity; SPS2 cows had reproductive tracts that were intermediate in cervical and uterine horn diameter, with longer uterine horns resting partially outside the pelvic cavity; and SPS3 cows had reproductive tracts that were larger and rested mostly outside the pelvic cavity. Cows that were SPS1 had a higher rate of pregnancy per artificial insemination (43.3 ± 3.7%) than cows that were SPS2 (36.9 ± 3.6%) or SPS3 (27.7 ± 4.3%). The percentage of cows with an SPS2 score differed in pregnancies per artificial insemination compared with SPS3 cows. The average days in milk was similar for SPS1, SPS2, and SPS3 cows (104.3 ± 3.5, 98.4 ± 3.4, and 94.7 ± 7.7, respectively). Ultrasound measurements of the uterine horn and cervical diameter, and length measurements of the uterine horns, cervix, and vagina confirmed differences among the SPS groups derived by transrectal palpation. The ease with which transrectal palpation can be used to determine the size and position of the reproductive tract attests to the relevance and usefulness of this scoring system to identify less fertile lactating dairy cows. The ability to do so with ease provides an opportunity to make economically relevant management decisions and maximize reproductive efficiency in a given herd. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Expression profile of genes as indicators of developmental competence and quality of in vitro fertilization and somatic cell nuclear transfer bovine embryos.

PubMed

Cánepa, Maria Jesús; Ortega, Nicolás Matías; Monteleone, Melisa Carolina; Mucci, Nicolas; Kaiser, German Gustavo; Brocco, Marcela; Mutto, Adrián

2014-01-01

Reproductive biotechnologies such as in vitro fertilization (IVF) and somatic cell nuclear transfer (SCNT) enable improved reproductive efficiency of animals. However, the birth rate of in vitro-derived embryos still lags behind that of their in vivo counterparts. Thus, it is critical to develop an accurate evaluation and prediction system of embryo competence, both for commercial purposes and for scientific research. Previous works have demonstrated that in vitro culture systems induce alterations in the relative abundance (RA) of diverse transcripts and thus compromise embryo quality. The aim of this work was to analyze the RA of a set of genes involved in cellular stress (heat shock protein 70-kDa, HSP70), endoplasmic reticulum (ER) stress (immunoglobulin heavy chain binding protein, Bip; proteasome subunit β5, PSMB5) and apoptosis (BCL-2 associated X protein, Bax; cysteine aspartate protease-3, Caspase-3) in bovine blastocysts produced by IVF or SCNT and compare it with that of their in vivo counterparts. Poly (A) + mRNA was isolated from three pools of 10 blastocysts per treatment and analyzed by real-time RT-PCR. The RA of three of the stress indicators analyzed (Bax, PSMB5 and Bip) was significantly increased in SCNT embryos as compared with that of in vivo-derived blastocysts. No significant differences were found in the RA of HSP70 and Caspase-3 gene transcripts. This study could potentially complement morphological analyses in the development of an effective and accurate technique for the diagnosis of embryo quality, ultimately aiding to improve the efficiency of assisted reproductive techniques (ART).

Reproductive Efficiency of a Mediterranean Endemic Zooxanthellate Coral Decreases with Increasing Temperature along a Wide Latitudinal Gradient

PubMed Central

Airi, Valentina; Gizzi, Francesca; Falini, Giuseppe; Levy, Oren; Dubinsky, Zvy; Goffredo, Stefano

2014-01-01

Investments at the organismal level towards reproduction and growth are often used as indicators of health. Understanding how such energy allocation varies with environmental conditions may, therefore, aid in predicting possible responses to global climatic change in the near future. For example, variations in seawater temperature may alter the physiological functioning, behavior, reproductive output and demographic traits (e.g., productivity) of marine organisms, leading to shifts in the structure, spatial range, and abundance of populations. This study investigated variations in reproductive output associated with local seawater temperature along a wide latitudinal gradient on the western Italian coast, in the zooxanthellate Mediterranean coral, Balanophyllia europaea. Reproductive potential varied significantly among sites, where B. europaea individuals from the warmest site experienced loss of oocytes during gametogenesis. Most of the early oocytes from warmest sites did not reach maturity, possibly due to inhibition of metabolic processes at high temperatures, causing B. europaea to reabsorb the oocytes and utilize them as energy for other vital functions. In a progressively warming Mediterranean, the efficiency of the energy invested in reproduction could be considerably reduced in this species, thereby affecting vital processes. Given the projected increase in seawater temperature as a consequence of global climate change, the present study adds evidence to the threats posed by high temperatures to the survival of B. europaea in the next decades. PMID:24618568

Effects of rapid temperature fluctuations prior to breeding on reproductive efficiency in replacement gilts

USDA-ARS?s Scientific Manuscript database

Recently, we determined that rapidly cooling pigs after acute heat stress (HS) resulted in a pathological condition, and because rapid temperature fluctuations are often associated with reduced reproductive success in sows it lends itself to the hypothesis that these conditions may be linked. Study ...

Reproductive success is energetically linked to foraging efficiency in Antarctic fur seals

PubMed Central

2017-01-01

The efficiency with which individuals extract energy from their environment defines their survival and reproductive success, and thus their selective contribution to the population. Individuals that forage more efficiently (i.e., when energy gained exceeds energy expended) are likely to be more successful at raising viable offspring than individuals that forage less efficiently. Our goal was to test this prediction in large long-lived mammals under free-ranging conditions. To do so, we equipped 20 lactating Antarctic fur seals (Arctocephalus gazella) breeding on Kerguelen Island in the Southern Ocean with tags that recorded GPS locations, depth and tri-axial acceleration to determine at-sea behaviours and detailed time-activity budgets during their foraging trips. We also simultaneously measured energy spent at sea using the doubly-labeled water (DLW) method, and estimated the energy acquired while foraging from 1) type and energy content of prey species present in scat remains, and 2) numbers of prey capture attempts determined from head acceleration. Finally, we followed the growth of 36 pups from birth until weaning (of which 20 were the offspring of our 20 tracked mothers), and used the relative differences in body mass of pups at weaning as an index of first year survival and thus the reproductive success of their mothers. Our results show that females with greater foraging efficiencies produced relatively bigger pups at weaning. These mothers achieved greater foraging efficiency by extracting more energy per minute of diving rather than by reducing energy expenditure. This strategy also resulted in the females spending less time diving and less time overall at sea, which allowed them to deliver higher quality milk to their pups, or allowed their pups to suckle more frequently, or both. The linkage we demonstrate between reproductive success and the quality of individuals as foragers provides an individual-based quantitative framework to investigate how changes in the availability and accessibility of prey can affect fitness of animals. PMID:28453563

Leaf dynamics in growth and reproduction of Xanthium canadense as influenced by stand density

PubMed Central

Ogawa, Takahiro; Oikawa, Shimpei; Hirose, Tadaki

2015-01-01

Background and Aims Leaf longevity is controlled by the light gradient in the canopy and also by the nitrogen (N) sink strength in the plant. Stand density may influence leaf dynamics through its effects on light gradient and on plant growth and reproduction. This study tests the hypothesis that the control by the light gradient is manifested more in the vegetative period, whereas the opposite is true when the plant becomes reproductive and develops a strong N sink. Methods Stands of Xanthium canadense were established at two densities. Emergence, growth and death of every leaf on the main stem and branches, and plant growth and N uptake were determined from germination to full senescence. Mean residence time and dry mass productivity were calculated per leaf number, leaf area, leaf mass and leaf N (collectively termed ‘leaf variables’) in order to analyse leaf dynamics and its effect on plant growth. Key Results Branching and reproductive activities were higher at low than at high density. Overall there was no significant difference in mean residence time of leaf variables between the two stands. However, early leaf cohorts on the main stem had a longer retention time at low density, whereas later cohorts had a longer retention time at high density. Branch leaves emerged earlier and tended to live longer at low than at high density. Leaf efficiencies, defined as carbon export per unit investment of leaf variables, were higher at low density in all leaf variables except for leaf number. Conclusions In the vegetative phase of plant growth, the light gradient strongly controls leaf longevity, whereas later the effects of branching and reproductive activities become stronger and over-rule the effect of light environment. As leaf N supports photosynthesis and also works as an N source for plant development, N use is pivotal in linking leaf dynamics with plant growth and reproduction. PMID:26248476

Trends in recombinant protein use in animal production.

PubMed

Gifre, Laia; Arís, Anna; Bach, Àlex; Garcia-Fruitós, Elena

2017-03-04

Recombinant technologies have made possible the production of a broad catalogue of proteins of interest, including those used for animal production. The most widely studied proteins for the animal sector are those with an important role in reproduction, feed efficiency, and health. Nowadays, mammalian cells and fungi are the preferred choice for recombinant production of hormones for reproductive purposes and fibrolytic enzymes to enhance animal performance, respectively. However, the development of low-cost products is a priority, particularly in livestock. The study of cell factories such as yeast and bacteria has notably increased in the last decades to make the new developed reproductive hormones and fibrolytic enzymes a real alternative to the marketed ones. Important efforts have also been invested to developing new recombinant strategies for prevention and therapy, including passive immunization and modulation of the immune system. This offers the possibility to reduce the use of antibiotics by controlling physiological processes and improve the efficacy of preventing infections. Thus, nowadays different recombinant fibrolytic enzymes, hormones, and therapeutic molecules with optimized properties have been successfully produced through cost-effective processes using microbial cell factories. However, despite the important achievements for reducing protein production expenses, alternative strategies to further reduce these costs are still required. In this context, it is necessary to make a giant leap towards the use of novel strategies, such as nanotechnology, that combined with recombinant technology would make recombinant molecules affordable for animal industry.

Evaluation of a reproductive index to estimate grasshopper sparrow and eastern meadowlark reproductive success

USGS Publications Warehouse

Althoff, Donald P.; Gipson, P.S.; Pontius, J.S.; Japuntich, R.D.

2009-01-01

We compared an index of reproductive success based on breeding behavior to actual nest fates of grasshopper sparrows (Ammodramus savannarum) and eastern meadowlarks (Sturnella magna) on 12 plots (4-ha). Concordance of results between the two methods was 58% for grasshopper sparrows and 42% for eastern meadowlarks on a plot-by-plot basis. The indirect method yielded higher estimates of reproductive activity than nest monitoring for the balance of the plots,. There was little evidence that brown-headed cowbird (Molothrus ater) parasitism influenced the estimates of reproductive success using the indirect method. We concluded that nests and about-to-fledge nestlings were missed during searches on some plots. It may be appropriate to use an indirect method to more efficiently survey territories and/or plots for species with hard-to-find nests or when monitoring large areas. Use of a reproductive index may be appropriate and more time-efficient than nest searching and monitoring for comparing management effects such as burning, grazing, haying, military training, and other localized disturbances that are likely to affect reproductive success of grasshopper sparrows and eastern meadowlarks. However, nest monitoring may be necessary for more precise estimates of productivity necessary for long-term monitoring. Nest monitoring results are also likely to allow for direct comparisons to results from other studies because the index method requires intimate knowledge of the species being evaluated - a factor that could lead to reduced precision because the experience level of technicians relying only on behavioral cues from study-to-study is likely to vary considerably.

Optimising reproductive performance of beef cows and replacement heifers.

PubMed

Diskin, M G; Kenny, D A

2014-05-01

A reproductively efficient beef cow herd is fundamental to meeting the protein and specifically, red meat demand of an ever increasing global population. However, attaining a high level of reproductive efficiency is underpinned by producers being cognisant of and achieving many key targets throughout the production cycle and requires significant technical competency. The lifetime productivity of the beef bred female commences from the onset of puberty and will be dictated by subsequent critical events including age at first calving, duration of the postpartum interval for each successive calving, conception and pregnancy rate and ultimately manifested as length of intercalving intervals and number of calves weaned over her lifetime. Puberty in heifers is a consequence of the interactive effects of genetics and both pre- and post-weaning nutrition. Early onset of puberty is essential to achieving the first main reproductive target for beef cow herds; first calving at 2 years of age. In calved heifers and mature cows, the onset of ovarian activity, postpartum is a key event dictating the calving interval. Again, this will be the product mainly of prepartum nutrition, manifested through body condition and the strength of the maternal bond between cow and calf, though there is increasing evidence of a modest genetic influence on this trait. Following the initiation of postpartum ovarian cyclicity, conception and subsequent pregnancy rate is generally a function of bull fertility in natural service herds and heat detection and timing of insemination in herds bred through artificial insemination. Cows and heifers should be maintained on a steady plane of nutrition during the breeding season, but the contribution of significant excesses or deficiencies of nutrients including protein and trace elements is likely to be minor where adequate pasture is available. While, increased efforts are being made internationally to genetically identify and select for more reproductively efficient beef cows, this is a more long-term strategy and will not replace the need for a high level of technical efficiency and management practice at farm level.

The mixture of cashew nut shell liquid and castor oil results in an efficient larvicide against Aedes aegypti that does not alter embryo-fetal development, reproductive performance or DNA integrity

PubMed Central

Vani, Juliana Miron; Monreal, Maria Tereza Ferreira Duenhas; Auharek, Sarah Alves; Cunha-Laura, Andréa Luiza; de Arruda, Eduardo José; Lima, Alessandra Ramos; da Silva, Cicera Maria; Antoniolli-Silva, Andréia Conceição Milan Brochado; de Lima, Dênis Pires; Beatriz, Adilson

2018-01-01

Dengue fever, chikungunya fever and Zika virus are epidemics in Brazil that are transmitted by mosquitoes, such as Aedes aegypti or Aedes albopictus. The liquid from shells of cashew nuts is attractive for its important biological and therapeutic activities, which include toxicity to mosquitoes of the genus Aedes. The present study evaluated the effects of a mixture of surfactants from natural cashew nutshell liquid and castor oil (named TaLCC-20) on the mortality of larvae and on the reproductive performance, embryonic and fetal development and genetic stability of Swiss mice. A total of 400 Ae. aegypti larvae (third larval stage) were treated with TaLCC-20 concentrations of 0.05 mg/L, 0.5 mg/L, or 5 mg/L (ppm). Twenty pregnant female mice were also orally administered TaLCC-20 at doses of 5 mg/kg and 50 mg/kg body weight (b.w.), and 10 animals were given only drinking water at 0.1 mL/10 g b.w. (orally). The results of a larvicide test demonstrated that 5 mg/mL TaLCC-20 killed 100% of larvae within three hours, which is comparable to the gold standard indicated by the Ministry of Health. Overall, these results show that TaLCC-20 is an efficient larvicide that does not induce genetic damage. In addition, changes in reproductive performance and embryo-fetal development appear positive, and the formulation is cost effective. Therefore, TaLCC-20 is an important product in the exploration of natural larvicides and can assist in fighting mosquitos as vectors for dengue fever, chikungunya fever and Zika virus, which are emerging/re-emerging and require proper management to ensure minimal harm to the human population. Therefore, TaLCC-20 can be considered a key alternative to commercial products, which are effective yet toxigenic. PMID:29554095

The mixture of cashew nut shell liquid and castor oil results in an efficient larvicide against Aedes aegypti that does not alter embryo-fetal development, reproductive performance or DNA integrity.

PubMed

Vani, Juliana Miron; Monreal, Maria Tereza Ferreira Duenhas; Auharek, Sarah Alves; Cunha-Laura, Andréa Luiza; de Arruda, Eduardo José; Lima, Alessandra Ramos; da Silva, Cicera Maria; Antoniolli-Silva, Andréia Conceição Milan Brochado; de Lima, Dênis Pires; Beatriz, Adilson; Oliveira, Rodrigo Juliano

2018-01-01

Dengue fever, chikungunya fever and Zika virus are epidemics in Brazil that are transmitted by mosquitoes, such as Aedes aegypti or Aedes albopictus. The liquid from shells of cashew nuts is attractive for its important biological and therapeutic activities, which include toxicity to mosquitoes of the genus Aedes. The present study evaluated the effects of a mixture of surfactants from natural cashew nutshell liquid and castor oil (named TaLCC-20) on the mortality of larvae and on the reproductive performance, embryonic and fetal development and genetic stability of Swiss mice. A total of 400 Ae. aegypti larvae (third larval stage) were treated with TaLCC-20 concentrations of 0.05 mg/L, 0.5 mg/L, or 5 mg/L (ppm). Twenty pregnant female mice were also orally administered TaLCC-20 at doses of 5 mg/kg and 50 mg/kg body weight (b.w.), and 10 animals were given only drinking water at 0.1 mL/10 g b.w. (orally). The results of a larvicide test demonstrated that 5 mg/mL TaLCC-20 killed 100% of larvae within three hours, which is comparable to the gold standard indicated by the Ministry of Health. Overall, these results show that TaLCC-20 is an efficient larvicide that does not induce genetic damage. In addition, changes in reproductive performance and embryo-fetal development appear positive, and the formulation is cost effective. Therefore, TaLCC-20 is an important product in the exploration of natural larvicides and can assist in fighting mosquitos as vectors for dengue fever, chikungunya fever and Zika virus, which are emerging/re-emerging and require proper management to ensure minimal harm to the human population. Therefore, TaLCC-20 can be considered a key alternative to commercial products, which are effective yet toxigenic.

Waste Separations and Pretreatment Workshop report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cruse, J.M.; Harrington, R.A.; Quadrel, M.J.

1994-01-01

This document provides the minutes from the Waste Separations and Pretreatment Workshop sponsored by the Underground Storage Tank-Integrated Demonstration in Salt Lake City, Utah, February 3--5, 1993. The Efficient Separations and Processing-Integrated Program and the Hanford Site Tank Waste Remediation System were joint participants. This document provides the detailed minutes, including responses to questions asked, an attendance list, reproductions of the workshop presentations, and a revised chart showing technology development activities.

Bloom-forming cyanobacteria support copepod reproduction and development in the Baltic Sea.

PubMed

Hogfors, Hedvig; Motwani, Nisha H; Hajdu, Susanna; El-Shehawy, Rehab; Holmborn, Towe; Vehmaa, Anu; Engström-Öst, Jonna; Brutemark, Andreas; Gorokhova, Elena

2014-01-01

It is commonly accepted that summer cyanobacterial blooms cannot be efficiently utilized by grazers due to low nutritional quality and production of toxins; however the evidence for such effects in situ is often contradictory. Using field and experimental observations on Baltic copepods and bloom-forming diazotrophic filamentous cyanobacteria, we show that cyanobacteria may in fact support zooplankton production during summer. To highlight this side of zooplankton-cyanobacteria interactions, we conducted: (1) a field survey investigating linkages between cyanobacteria, reproduction and growth indices in the copepod Acartia tonsa; (2) an experiment testing relationships between ingestion of the cyanobacterium Nodularia spumigena (measured by molecular diet analysis) and organismal responses (oxidative balance, reproduction and development) in the copepod A. bifilosa; and (3) an analysis of long term (1999-2009) data testing relationships between cyanobacteria and growth indices in nauplii of the copepods, Acartia spp. and Eurytemora affinis, in a coastal area of the northern Baltic proper. In the field survey, N. spumigena had positive effects on copepod egg production and egg viability, effectively increasing their viable egg production. By contrast, Aphanizomenon sp. showed a negative relationship with egg viability yet no significant effect on the viable egg production. In the experiment, ingestion of N. spumigena mixed with green algae Brachiomonas submarina had significant positive effects on copepod oxidative balance, egg viability and development of early nauplial stages, whereas egg production was negatively affected. Finally, the long term data analysis identified cyanobacteria as a significant positive predictor for the nauplial growth in Acartia spp. and E. affinis. Taken together, these results suggest that bloom forming diazotrophic cyanobacteria contribute to feeding and reproduction of zooplankton during summer and create a favorable growth environment for the copepod nauplii.

Bloom-Forming Cyanobacteria Support Copepod Reproduction and Development in the Baltic Sea

PubMed Central

Hogfors, Hedvig; Motwani, Nisha H.; Hajdu, Susanna; El-Shehawy, Rehab; Holmborn, Towe; Vehmaa, Anu; Engström-Öst, Jonna; Brutemark, Andreas; Gorokhova, Elena

2014-01-01

It is commonly accepted that summer cyanobacterial blooms cannot be efficiently utilized by grazers due to low nutritional quality and production of toxins; however the evidence for such effects in situ is often contradictory. Using field and experimental observations on Baltic copepods and bloom-forming diazotrophic filamentous cyanobacteria, we show that cyanobacteria may in fact support zooplankton production during summer. To highlight this side of zooplankton-cyanobacteria interactions, we conducted: (1) a field survey investigating linkages between cyanobacteria, reproduction and growth indices in the copepod Acartia tonsa; (2) an experiment testing relationships between ingestion of the cyanobacterium Nodularia spumigena (measured by molecular diet analysis) and organismal responses (oxidative balance, reproduction and development) in the copepod A. bifilosa; and (3) an analysis of long term (1999–2009) data testing relationships between cyanobacteria and growth indices in nauplii of the copepods, Acartia spp. and Eurytemora affinis, in a coastal area of the northern Baltic proper. In the field survey, N. spumigena had positive effects on copepod egg production and egg viability, effectively increasing their viable egg production. By contrast, Aphanizomenon sp. showed a negative relationship with egg viability yet no significant effect on the viable egg production. In the experiment, ingestion of N. spumigena mixed with green algae Brachiomonas submarina had significant positive effects on copepod oxidative balance, egg viability and development of early nauplial stages, whereas egg production was negatively affected. Finally, the long term data analysis identified cyanobacteria as a significant positive predictor for the nauplial growth in Acartia spp. and E. affinis. Taken together, these results suggest that bloom forming diazotrophic cyanobacteria contribute to feeding and reproduction of zooplankton during summer and create a favorable growth environment for the copepod nauplii. PMID:25409500

Double impact of sterilizing pathogens: added value of increased life expectancy on pest control effectiveness.

PubMed

Berec, Luděk; Maxin, Daniel

2012-06-01

Sterilizing pathogens are commonly assumed not to affect longevity of infected individuals, and if they do then negatively. Examples abound, however, of species in which the absence of reproduction actually increases life expectancy. This happens because by decreasing the energy outlay on reproduction individuals with lowered reproduction can live longer. Alternatively, fertile individuals are more susceptible to predators or parasitoids if the latter can capitalize on mating signals of the former. Here we develop and analyze an SI epidemiological model to explore whether and to what extent does such a life expectancy prolongation due to sterilizing pathogens affect host dynamics. In particular, we are interested in an added value of increased life expectancy on the possibility of successful pest control, that is, the effect of increased lifespan and hence increased potential of the infected individuals to spread the disease on pest control effectiveness. We show that although the parameter range in which we observe an effect of increased lifespan of the sterilized individuals is not large, the effect itself can be significant. In particular, the increase in pest control effectiveness can be very dramatic when disease transmission efficiency is close to birth rate, mortality rate of susceptibles is relatively high (i.e., the species is relatively short-lived), and sterilization efficiency is relatively high. Our results thus characterize pathogens that are promising candidates for an effective pest control and that might possibly be engineered if not occurring naturally.

Oral administration of pharmacological doses of vitamins C and E reduces reproductive fitness and impairs the ovarian and uterine functions of female mice.

PubMed

Tarín, J J; Pérez-Albalá, S; Pertusa, J F; Cano, A

2002-03-15

This study aims to ascertain whether oral administration of pharmacological doses of Vitamins C and E has any detrimental effect on reproductive fitness of female mice. We fed hybrid female mice from the first day of weaning a standard diet supplemented or not supplemented with pharmacological doses of Vitamins C and E. At the age of 28 weeks, we individually caged females with a male for the rest of their reproductive life. We performed a series of mating experiments to ascertain the number of oocytes ovulated and the potential for embryo development in vitro to the blastocyst stage and in vivo to Day 12 of gestation. The antioxidant diet decreased the frequency of litters, litter size, total number of offspring born and survival of male pups to weaning. This effect was associated with lower number of corpora lutea in the left ovary, decreased percentage of viable fetuses, and higher number of fetal resorptions in the left uterine horn when compared to the control group. The strategy of supplementing the diet with antioxidant vitamins to prevent the age associated decrease in reproductive potential should not be implemented in human beings until a safe and efficient diet is designed.

Characterization of growth and reproduction performance, transgene integration, expression and transmission patterns in transgenic pigs produced by piggyBac transposition-mediated gene transfer

PubMed Central

Zeng, Fang; Li, Zicong; Cai, Gengyuan; Gao, Wenchao; Jiang, Gelong; Liu, Dewu; Urschitz, Johann; Moisyadi, Stefan; Wu, Zhenfang

2016-01-01

Previously we successfully produced a group of EGFP-expressing founder transgenic pigs by a newly developed efficient and simple pig transgenesis method based on cytoplasmic injection of piggyBac plasmids. In this study, we investigated the growth and reproduction performance, and characterized the transgene insertion, transmission and expression patterns in transgenic pigs generated by piggyBac transposition. Results showed that transgene has no injurious effect on the growth and reproduction of transgenic pigs. Multiple copies of monogenic EGFP transgene were inserted at noncoding sequences of host genome, and passed from founder transgenic pigs to their transgenic offspring in segregation or linkage manner. The EGFP transgene was ubiquitously expressed in transgenic pigs, and its expression intensity was associated with transgene copy number but not related to its promoter DNA methylation level. To the best of our knowledge, this is first study that fully described the growth and reproduction performance, transgene insertion, expression and transmission profiles in transgenic pigs produced by piggyBac system. It not only demonstrates that piggyBac transposition-mediated gene transfer is an effective and favourable approach for pig transgenesis, but also provides scientific information for understanding the transgene insertion, expression and transmission patterns in transgenic animals produced by piggyBac transposition. PMID:27565868

In Vivo Functional Genomic Studies of Sterol Carrier Protein-2 Gene in the Yellow Fever Mosquito

PubMed Central

Peng, Rong; Maklokova, Vilena I.; Chandrashekhar, Jayadevi H.; Lan, Que

2011-01-01

A simple and efficient DNA delivery method to introduce extrachromosomal DNA into mosquito embryos would significantly aid functional genomic studies. The conventional method for delivery of DNA into insects is to inject the DNA directly into the embryos. Taking advantage of the unique aspects of mosquito reproductive physiology during vitellogenesis and an in vivo transfection reagent that mediates DNA uptake in cells via endocytosis, we have developed a new method to introduce DNA into mosquito embryos vertically via microinjection of DNA vectors in vitellogenic females without directly manipulating the embryos. Our method was able to introduce inducible gene expression vectors transiently into F0 mosquitoes to perform functional studies in vivo without transgenic lines. The high efficiency of expression knockdown was reproducible with more than 70% of the F0 individuals showed sufficient gene expression suppression (<30% of the controls' levels). At the cohort level, AeSCP-2 expression knockdown in early instar larvae resulted in detectable phenotypes of the expression deficiency such as high mortality, lowered fertility, and distorted sex ratio after induction of AeSCP-2 siRNA expression in vivo. The results further confirmed the important role of AeSCP-2 in the development and reproduction of A. aegypti. In this study, we proved that extrachromosaomal transient expression of an inducible gene from a DNA vector vertically delivered via vitellogenic females can be used to manipulate gene expression in F0 generation. This new method will be a simple and efficient tool for in vivo functional genomic studies in mosquitoes. PMID:21437205

Evolutionary optimality applied to Drosophila experiments: hypothesis of constrained reproductive efficiency.

PubMed

Novoseltsev, V N; Arking, R; Novoseltseva, J A; Yashin, A I

2002-06-01

The general purpose of the paper is to test evolutionary optimality theories with experimental data on reproduction, energy consumption, and longevity in a particular Drosophila genotype. We describe the resource allocation in Drosophila females in terms of the oxygen consumption rates devoted to reproduction and to maintenance. The maximum ratio of the component spent on reproduction to the total rate of oxygen consumption, which can be realized by the female reproductive machinery, is called metabolic reproductive efficiency (MRE). We regard MRE as an evolutionary constraint. We demonstrate that MRE may be evaluated for a particular Drosophila phenotype given the fecundity pattern, the age-related pattern of oxygen consumption rate, and the longevity. We use a homeostatic model of aging to simulate a life history of a representative female fly, which describes the control strain in the long-term experiments with the Wayne State Drosophila genotype. We evaluate the theoretically optimal trade-offs in this genotype. Then we apply the Van Noordwijk-de Jong resource acquisition and allocation model, Kirkwood's disposable soma theory. and the Partridge-Barton optimality approach to test if the experimentally observed trade-offs may be regarded as close to the theoretically optimal ones. We demonstrate that the two approaches by Partridge-Barton and Kirkwood allow a positive answer to the question, whereas the Van Noordwijk-de Jong approach may be used to illustrate the optimality. We discuss the prospects of applying the proposed technique to various Drosophila experiments, in particular those including manipulations affecting fecundity.

Culture and religious beliefs in relation to reproductive health.

PubMed

Arousell, Jonna; Carlbom, Aje

2016-04-01

An increasing number of contemporary research publications acknowledge the influence of religion and culture on sexual and reproductive behavior and health-care utilization. It is currently hypothesized that religious influences can partly explain disparities in sexual and reproductive health outcomes. In this paper, we will pay particular attention to Muslims in sexual and reproductive health care. This review reveals that knowledge about devout Muslims' own experience of sexual and reproductive health-care matters is limited, thus providing weak evidence for modeling of efficient practical guidelines for sexual and reproductive health care directed at Muslim patients. Successful outcomes in sexual and reproductive health of Muslims require both researchers and practitioners to acknowledge religious heterogeneity and variability, and individuals' possibilities to negotiate Islamic edicts. Failure to do so could lead to inadequate health-care provision and, in the worst case, to suboptimal encounters between migrants with Muslim background and the health-care providers in the receiving country. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Reproductive and productive performances of Santa Inês ewes submitted to breeding in different periods of the Amazonian humid tropical climate.

PubMed

Soares, Felipe Nogueira; Oliveira, Maria Emilia Franco; Padilha-Nakaghi, Luciana Cristina; de Oliveira, Luís Guilherme; Feliciano, Marcus Antônio Rossi; de Oliveira, Felipe Brener Bezerra; Teixeira, Pedro Paulo Maia; Vicente, Wilter Ricardo Russiano; Faturi, Cristian; Rodrigues, Luiz Fernando de Souza

2015-12-01

The objective of this study was to evaluate the reproductive and productive performance of Santa Inês ewes bred at different times of the year in humid tropical climate. One hundred and forty-eight Santa Inês ewes were grouped according to the time of the year of their breeding season (i.e., mating period) (dry/wet, wet, wet/dry, and dry season). The service type was natural mating and the ewes and rams were kept together every night for 45 days. Reproductive efficiency was assessed by service, pregnancy, lambing, prolificacy, twinning, pregnancy loss, weaning, and lamb mortality rates. Ewes were weighed at the beginning and at the end of the breeding season and before and after parturition, and sequential weighing of the lambs was performed (at birth, 15, 30, 60, and 90 days). Reproductive efficiency index (number of lambs weaned/total of served ewes) and productive efficiency (kg of weaned lamb/kg of served or lambed ewes) were calculated. All ewes expressed estrus early in the breeding season; however, a higher percentage (53.5 and 7.1 % at 30 and 45 days, respectively) of ewes returned to estrus during the wet/dry period. The lower rates (13.9 %) of return to estrus at 30 days were during the wet season (P < 0.05). There were no (P > 0.05) effects of breeding seasons on the remaining reproductive rates. Ewes that lambed during the wet/dry transition period weighted less, before (40.5 ± 2.5 kg) and after (38.6 ± 1.6 kg) parturition, than those of other groups (P < 0.05). Lamb weight at birth did not vary between groups, however, weight at weaning was higher (15.6 ± 2.1 kg) in lambs born during the wet season (P < 0.05). The reproductive efficiency index was lower (0.66) when the breeding season took place during the dry/wet period (P < 0.05). Productive rates were significantly higher (0.29 and 0.33 for kg of weaned lamb/kg of served and lambed ewes, respectively; P < 0.05) in ewes served in the dry season. The reproductive performance of Santa Inês ewes was not significantly influenced by the period of the year in which the breeding seasons took place, allowing for four breeding seasons a year in the Amazon region. Variations between periods in return to estrus rates, weight of ewes close to parturition and lamb weight at weaning indicate that climate changes can also affect reproductive rates.

Ongoing research on mammalian cloning and embryo stem cell technologies: bioethics of their potential medical applications.

PubMed

Revel, M

2000-07-01

Reproduction by cloning has been achieved by transfer into enucleated oocytes of nuclei from embryonic cells and more recently from cells of adult animals. The efficiency at which embryos produced by such nuclear transfers will develop into healthy newborns is very low but has succeeded in producing some cloned bovines, ovines and mice. Since the first report of sheep cloning from an adult cell in 1997, the potential applications of reproductive cloning in human medicine have been envisaged amidst a flurry of moral debates. Although the technology is still far from being ready for any human use, it has been condemned up front. It has also led to irrational fantasies and fears, based mainly on the misconception that genetic identity means identical twin personalities. Scientific research is ongoing to refine the cloning technology for applications in the production of genetically homogeneous farm animals with useful nutritional or therapeutic genetic traits. A new area of research is non-reproductive therapeutic cloning for the purpose of producing autologous embryonic cells and tissues for transplantation.

Responses of Lumbriculus variegatus to activated carbon amendments in uncontaminated sediments.

PubMed

Nybom, Inna; Werner, David; Leppänen, Matti T; Siavalas, George; Christanis, Kimon; Karapanagioti, Hrissi K; Kukkonen, Jussi V K; Akkanen, Jarkko

2012-12-04

Activated carbon (AC) amendment is a recently developed sediment remediation method. The strong hydrophobic organic contaminant sorption efficiency of AC has been shown in several studies, but effects on benthic organisms require more investigation. The AC induced effects on egestion rate, growth and reproduction of Lumbriculus variegatus were studied by applying bituminous coal based AC in three different particle size fractions, namely <63 μm (90%, AC(p)), 63-200 μm (AC(m)) and 1000 μm (AC(g)), to natural uncontaminated (HS) and artificial sediment (AS). Egestion rate, growth and reproduction decreased with increasing AC concentration and finer AC particle fractions, effects being stronger on HS than on AS sediment. Lipid content in AS was reduced already at the lowest AC doses applied (AC(p) and AC(m) 0.05%, AC(g) 0.25%). In addition, hormesis-like response was observed in growth (AS) and reproduction (AS, HS) indicating that AC may disturb organisms even at very low doses. Potential ecological effects need to be further evaluated in an amendment- and site-specific manner.

TCF21 is related to testis growth and development in broiler chickens.

PubMed

Zhang, Hui; Na, Wei; Zhang, Hong-Li; Wang, Ning; Du, Zhi-Qiang; Wang, Shou-Zhi; Wang, Zhi-Peng; Zhang, Zhiwu; Li, Hui

2017-02-24

Large amounts of fat deposition often lead to loss of reproductive efficiency in humans and animals. We used broiler chickens as a model species to conduct a two-directional selection for and against abdominal fat over 19 generations, which resulted in a lean and a fat line. Direct selection for abdominal fat content also indirectly resulted in significant differences (P < 0.05) in testis weight (TeW) and in TeW as a percentage of total body weight (TeP) between the lean and fat lines. A total of 475 individuals from the generation 11 (G 11 ) were genotyped. Genome-wide association studies revealed two regions on chicken chromosomes 3 and 10 that were associated with TeW and TeP. Forty G 16 individuals (20 from each line), were further profiled by focusing on these two chromosomal regions, to identify candidate genes with functions that may be potentially related to testis growth and development. Of the nine candidate genes identified with database mining, a significant association was confirmed for one gene, TCF21, based on mRNA expression analysis. Gene expression analysis of the TCF21 gene was conducted again across 30 G 19 individuals (15 individuals from each line) and the results confirmed the findings on the G 16 animals. This study revealed that the TCF21 gene is related to testis growth and development in male broilers. This finding will be useful to guide future studies to understand the genetic mechanisms that underlie reproductive efficiency.

The ecology and evolutionary endocrinology of reproduction in the human female.

PubMed

Vitzthum, Virginia J

2009-01-01

Human reproductive ecology (HRE) is the study of the mechanisms that link variation in reproductive traits with variation in local habitats. Empirical and theoretical contributions from biological anthropology, physiology, and demography have established the foundation necessary for developing a comprehensive understanding, grounded in life history theory (LHT), of temporal, individual, and populational variation in women's reproductive functioning. LHT posits that natural selection leads to the evolution of mechanisms that tend to allocate resources to the competing demands of growth, reproduction, and survival such that fitness is locally maximized. (That is, among alternative allocation patterns exhibited in a population, those having the highest inclusive fitness will become more common over generational time.) Hence, strategic modulation of reproductive effort is potentially adaptive because investment in a new conception may risk one's own survival, future reproductive opportunities, and/or current offspring survival. The hypothalamic-pituitary-ovarian (HPO) axis is the principal neuroendocrine pathway by which the human female modulates reproductive functioning according to the changing conditions in her habitat. Adjustments of reproductive investment in a potential conception are manifested in temporal and individual variation in ovarian cycle length, ovulation, hormone levels, and the probability of conception. Understanding the extent and causes of adaptive and non-adaptive variation in ovarian functioning is fundamental to ascertaining the proximate and remote determinants of human reproductive patterns. In this review I consider what is known and what still needs to be learned of the ecology of women's reproductive biology, beginning with a discussion of the principal explanatory frameworks in HRE and the biometry of ovarian functioning. Turning next to empirical studies, it is evident that marked variation between cycles, women, and populations is the norm rather than an aberration. Other than woman's age, the determinants of these differences are not well characterized, although developmental conditions, dietary practices, genetic variation, and epigenetic mechanisms have all been hypothesized to play some role. It is also evident that the reproductive functioning of women born and living in arduous conditions is not analogous to that of athletes, dieters, or even the lower end of the "normal range" of HPO functioning in wealthier populations. Contrary to the presumption that humans have low fecundity and an inefficient reproductive system, both theory and present evidence suggest that we may actually have very high fecundity and a reproductive system that has evolved to be flexible, ruthlessly efficient and, most importantly, strategic. Copyright 2009 Wiley-Liss, Inc.

Sensivity of Adult Reproduction and Reproductive Development in Japanese Medaka Exposed to 4-Tert-octylphenol

EPA Science Inventory

In response to legislation, the USEPA is developing assessment tools for identifying chemicals likely to cause sublethal effects on reproduction and reproductive development with ultimate adverse impacts on fish populations. While fecundity and fertility data from short-term adul...

Physiology and Endocrinology Symposium: The current status of heat shock in early embryonic survival and reproductive efficiency

USDA-ARS?s Scientific Manuscript database

The Physiology and Endocrinology Symposium entitled “The Current Status of Heat Shock in Early Embryonic Survival and Reproductive Efficiency” was held at the Joint ADSA-CSAS-AMPA-WSAS-ASAS Meeting in Phoenix, Arizona, July 15 to 19, 2012. In recent years, data has accumulated suggesting a role for...

On the botanic model of plant growth with intermediate vegetative-reproductive stage.

PubMed

Ioslovich, Ilya; Gutman, Per-Olof

2005-11-01

The application of dynamic optimization to mathematical models of ontogenic biological growth has been the subject of much research [see e.g. . J. Theor. Biol. 33, 299-307]. Kozłowsky and Ziółko [1988. Thor. Popul. Biol. 34, 118-129] and Ziółko and Kozłowski [1995. IEEE Trans. Automat. Contr. 40(10), 1779-1783] presented a model with gradual transition from vegetative to reproductive growth. The central point of their model is a mixed state-control constraint on the rate of reproductive growth, which leads to a mixed vegetative-reproductive growth period. Their model is modified here in order to take into account the difference of photosynthesis use efficiency when energy is accumulated in the vegetative and in the reproductive organs of a plant, respectively. The simple assumption on correlation between photosynthesis and temperature permits us to modify the model in a form that is useful for changing climate. Unfortunately, the mathematical solution of the optimal control problem in Kozłowsky and Ziółko (1988) and Ziółko and Kozłowski (1995) is incorrect. The strict mathematical solution is presented here, the numerical example from is solved, and the results are compared. The influence of the length of the season and the relative photosynthesis use efficiency, as well as of the potential sink demand of the reproductive organs, on the location and duration of the mixed vegetative-reproduction period of growth is investigated numerically. The results show that the mixed growth period is increased and shifted toward the end of the season when the lengths of the season is increased. Additional details of the sensitivity analysis are also presented.

Reproductive allocation strategies in desert and Mediterranean populations of annual plants grown with and without water stress.

PubMed

Aronson, J; Kigel, J; Shmida, A

1993-03-01

Reproductive effort (relative allocation of biomass to diaspore production) was compared in matched pairs of Mediterranean and desert populations of three unrelated annual species, Erucaria hispanica (L.) Druce, Bromus fasciculatus C. Presl. and Brachypodium distachyon (L.) Beauv., grown under high and low levels of water availability in a common-environment experiment. Desert populations in all three species showed higher reproductive effort than corresponding Mediterranean populations, as expressed by both a reproductive index (RI= reproductive biomass/vegetative biomass), and a reproductive efficiency index (REI=number of diaspores/total plant biomass). Moreover, in E. hispanica and Brachypodium distachyon, inter-populational differences in reproductive effort were greater under water stress, the main limiting factor for plant growth in the desert. These results indicate that variability in reproductive effort in response to drought is a critical and dynamic component of life history strategies in annual species in heterogeneous, unpredictable xeric environments. When subjected to water stress the Mediterranean populations of E. hispanica and B. distachyon showed greater plasticity (e.g. had a greater reduction) in reproductive effort than the desert populations, while in Bromus fasciculatus both populations showed similar amounts of plasticity.

Divergence for residual feed intake of Holstein-Friesian cattle during growth did not affect production and reproduction during lactation.

PubMed

Macdonald, K A; Thomson, B P; Waghorn, G C

2016-11-01

Residual feed intake (RFI) is the difference between actual and predicted dry matter intake (DMI) of individual animals. Recent studies with Holstein-Friesian calves have identified an ~20% difference in RFI during growth (calf RFI) and these groups remained divergent in RFI during lactation. The objective of the experiment described here was to determine if cows selected for divergent RFI as calves differed in milk production, reproduction or in the profiles of BW and body condition score (BCS) change during lactation, when grazing pasture. The cows used in the experiment (n=126) had an RFI of -0.88 and +0.75 kg DM intake/day for growth as calves (efficient and inefficient calf RFI groups, respectively) and were intensively grazed at four stocking rates (SR) of 2.2, 2.6, 3.1 and 3.6 cows/ha on self-contained farmlets, over 3 years. Each SR treatment had equal number of cows identified as low and high calf RFI, with 24, 28, 34 and 40/11 ha farmlet. The cows divergent for calf RFI were randomly allocated to each SR. Although SR affected production, calf RFI group (low or high) did not affect milk production, reproduction, BW, BCS or changes in these parameters throughout lactation. The most efficient animals (low calf RFI) lost similar BW and BCS as the least efficient (high calf RFI) immediately post-calving, and regained similar BW and BCS before their next calving. These results indicate that selection for RFI as calves to increase efficiency of feed utilisation did not negatively affect farm productivity variables (milk production, BCS, BW and reproduction) as adults when managed under an intensive pastoral grazing system.

Managing the reproductive performance of beef cows.

PubMed

Diskin, M G; Kenny, D A

2016-07-01

A reproductively efficient beef cow herd will be fundamental to meeting the protein and specifically, red meat demand of an ever increasing global population. However, attaining a high level of reproductive efficiency is underpinned by producers being cognizant of and achieving many key targets throughout the production cycle and requires considerable technical competency. The lifetime productivity of the beef-bred female commences from the onset of puberty and will be dictated by subsequent critical events including age at first calving, duration of the postpartum interval after successive calvings, conception and pregnancy rate, and ultimately manifested as length of intercalving intervals. In calved heifers and mature cows, the onset of ovarian activity, postpartum is a key event dictating the calving interval. Again, this will be the product mainly of prepartum nutrition, manifested through body condition score and the strength of the maternal bond between cow and calf, though there is increasing evidence of a modest genetic influence on this trait. After the initiation of postpartum ovarian cyclicity, conception and subsequent pregnancy rate is generally a function of bull fertility in natural service herds and heat detection and timing of insemination in herds bred through AI. Cows and heifers should be maintained on a steady plane of nutrition during the breeding season, but the contribution of significant excesses or deficiencies of nutrients including protein and trace elements is likely to be minor where adequate pasture is available. Although increased efforts are being made internationally to genetically identify and select for more reproductively efficient beef cows, this is a more long-term strategy and will not replace the need for a high level of technical efficiency and management practice at farm level. Copyright © 2016 Elsevier Inc. All rights reserved.

Oyster reproduction is affected by exposure to polystyrene microplastics

PubMed Central

Sussarellu, Rossana; Suquet, Marc; Thomas, Yoann; Lambert, Christophe; Fabioux, Caroline; Pernet, Marie Eve Julie; Le Goïc, Nelly; Quillien, Virgile; Mingant, Christian; Epelboin, Yanouk; Corporeau, Charlotte; Guyomarch, Julien; Robbens, Johan; Paul-Pont, Ika; Soudant, Philippe; Huvet, Arnaud

2016-01-01

Plastics are persistent synthetic polymers that accumulate as waste in the marine environment. Microplastic (MP) particles are derived from the breakdown of larger debris or can enter the environment as microscopic fragments. Because filter-feeder organisms ingest MP while feeding, they are likely to be impacted by MP pollution. To assess the impact of polystyrene microspheres (micro-PS) on the physiology of the Pacific oyster, adult oysters were experimentally exposed to virgin micro-PS (2 and 6 µm in diameter; 0.023 mg·L−1) for 2 mo during a reproductive cycle. Effects were investigated on ecophysiological parameters; cellular, transcriptomic, and proteomic responses; fecundity; and offspring development. Oysters preferentially ingested the 6-µm micro-PS over the 2-µm-diameter particles. Consumption of microalgae and absorption efficiency were significantly higher in exposed oysters, suggesting compensatory and physical effects on both digestive parameters. After 2 mo, exposed oysters had significant decreases in oocyte number (−38%), diameter (−5%), and sperm velocity (−23%). The D-larval yield and larval development of offspring derived from exposed parents decreased by 41% and 18%, respectively, compared with control offspring. Dynamic energy budget modeling, supported by transcriptomic profiles, suggested a significant shift of energy allocation from reproduction to structural growth, and elevated maintenance costs in exposed oysters, which is thought to be caused by interference with energy uptake. Molecular signatures of endocrine disruption were also revealed, but no endocrine disruptors were found in the biological samples. This study provides evidence that micro-PS cause feeding modifications and reproductive disruption in oysters, with significant impacts on offspring. PMID:26831072

A New Curve of Critical Nitrogen Concentration Based on Spike Dry Matter for Winter Wheat in Eastern China.

PubMed

Zhao, Ben; Ata-Ui-Karim, Syed Tahir; Yao, Xia; Tian, YongChao; Cao, WeiXing; Zhu, Yan; Liu, XiaoJun

2016-01-01

Diagnosing the status of crop nitrogen (N) helps to optimize crop yield, improve N use efficiency, and reduce the risk of environmental pollution. The objectives of the present study were to develop a critical N (Nc) dilution curve for winter wheat (based on spike dry matter [SDM] during the reproductive growth period), to compare this curve with the existing Nc dilution curve (based on plant dry matter [DM] of winter wheat), and to explore its ability to reliably estimate the N status of winter wheat. Four field experiments, using varied N fertilizer rates (0-375 kg ha-1) and six cultivars (Yangmai16, Ningmai13, Ningmai9, Aikang58, Yangmai12, Huaimai 17), were conducted in the Jiangsu province of eastern China. Twenty plants from each plot were sampled to determine the SDM and spike N concentration (SNC) during the reproductive growth period. The spike Nc curve was described by Nc = 2.85×SDM-0.17, with SDM ranging from 0.752 to 7.233 t ha-1. The newly developed curve was lower than the Nc curve based on plant DM. The N nutrition index (NNI) for spike dry matter ranged from 0.62 to 1.1 during the reproductive growth period across the seasons. Relative yield (RY) increased with increasing NNI; however, when NNI was greater than 0.96, RY plateaued and remained stable. The spike Nc dilution curve can be used to correctly identify the N nutrition status of winter wheat to support N management during the reproductive growth period for winter wheat in eastern China.

Oyster reproduction is affected by exposure to polystyrene microplastics.

PubMed

Sussarellu, Rossana; Suquet, Marc; Thomas, Yoann; Lambert, Christophe; Fabioux, Caroline; Pernet, Marie Eve Julie; Le Goïc, Nelly; Quillien, Virgile; Mingant, Christian; Epelboin, Yanouk; Corporeau, Charlotte; Guyomarch, Julien; Robbens, Johan; Paul-Pont, Ika; Soudant, Philippe; Huvet, Arnaud

2016-03-01

Plastics are persistent synthetic polymers that accumulate as waste in the marine environment. Microplastic (MP) particles are derived from the breakdown of larger debris or can enter the environment as microscopic fragments. Because filter-feeder organisms ingest MP while feeding, they are likely to be impacted by MP pollution. To assess the impact of polystyrene microspheres (micro-PS) on the physiology of the Pacific oyster, adult oysters were experimentally exposed to virgin micro-PS (2 and 6 µm in diameter; 0.023 mg·L(-1)) for 2 mo during a reproductive cycle. Effects were investigated on ecophysiological parameters; cellular, transcriptomic, and proteomic responses; fecundity; and offspring development. Oysters preferentially ingested the 6-µm micro-PS over the 2-µm-diameter particles. Consumption of microalgae and absorption efficiency were significantly higher in exposed oysters, suggesting compensatory and physical effects on both digestive parameters. After 2 mo, exposed oysters had significant decreases in oocyte number (-38%), diameter (-5%), and sperm velocity (-23%). The D-larval yield and larval development of offspring derived from exposed parents decreased by 41% and 18%, respectively, compared with control offspring. Dynamic energy budget modeling, supported by transcriptomic profiles, suggested a significant shift of energy allocation from reproduction to structural growth, and elevated maintenance costs in exposed oysters, which is thought to be caused by interference with energy uptake. Molecular signatures of endocrine disruption were also revealed, but no endocrine disruptors were found in the biological samples. This study provides evidence that micro-PS cause feeding modifications and reproductive disruption in oysters, with significant impacts on offspring.

Transgenic Reproductive Cell Ablation.

PubMed

Lawit, Shai J; Chamberlin, Mark A

2017-01-01

Numerous cell ablation technologies are available and have been used in reproductive tissues, particularly for male tissues and cells. The importance of ablation of reproductive tissues is toward a fundamental understanding reproductive tissue development and fertilization, as well as, in developing sterility lines important to breeding strategies. Here, we describe techniques for developing ablation lines for both male and female reproductive cells. Also discussed are techniques for analysis, quality control, maintenance, and the lessening of pleiotropism in such lines.

Impact of reproductive health on socio-economic development: a case study of Nigeria.

PubMed

Adinma, J I B; Adinma, E D

2011-03-01

The link between reproductive health, sexual and reproductive right, and development was highlighted at the International Conference on Population and Development held in Egypt. Developmental disparities are related to socio-economic differences which have led to the identification of distinct socio-economic classifications of nations. Human development represents the socioeconomic standing of any nation, in addition to literacy status and life expectancy. Africa accounts for 25% of the world's landmass but remains the world's poorest continent. Nigeria, the most populous country in Africa, has policies and programmes geared towards the improvement of its socio-economic standing and overal development, with little positive result. Reproductive health is a panacea towards reversing the stalled socio-economic growth of Nigeria as evident from the linkage between reproductive health and development, highlighted in Millennium Development Goals 3, 4, 5 and 6. Fast tracking Nigeria's development requires implementation of reproductive health policies and programmes targeted on women and children.

Reproductive technologies relevant to the genome resource bank in Carnivora.

PubMed

Amstislavsky, S; Lindeberg, H; Luvoni, Gc

2012-02-01

Carnivora is one of the most species-rich order of Mammalia. Some species, e.g. domestic cats, dogs and ferrets, are among the most popular pets; others, such as minks and farmed foxes, have economic value for the fur breeding industry. Still others, such as tigers, bears and other top predators, have great impact on the health of natural ecosystems. Most if not all Carnivora species have great cultural and aesthetic importance for man. There are enormous differences between mammalian species in reproductive physiology, and it is not surprising that reproductive technologies can be used with high efficiency with some animal groups, e.g. most farm animals and laboratory rodents, but are very laborious when used with Carnivora species, which often possess unique reproductive traits. The efficiency of assisted reproductive technology (ART) applied to semi-domestic, non-domestic and especially to endangered species of Carnivora remains extremely low in most cases, and often the first positive result reported is the only instance when ART has been successful with that species. Although there are approximately 270 species in the Carnivora order, to the best of our knowledge, successful published attempts to apply ART have been reported for only four families: Mustelidae, Felidae, Canidae and Ursidae. The main achievements in ART, embryo technology in particular, for these families of Carnivora, together with challenges and problems, are reviewed in the relevant sections. © 2011 Blackwell Verlag GmbH.

Reproductive Medicine in Amphibians.

PubMed

Chai, Norin

2017-05-01

Reproduction of amphibians includes ovulation, spermiation, fertilization, oviposition, larval stage and development, and metamorphosis. A problem at any stage could lead to reproductive failure. To stimulate reproduction, environmental conditions must be arranged to simulate changes in natural habits. Reproductive life history is well documented in amphibians; a thorough knowledge of this subject will aid the practitioner in diagnosis and treatment. Technologies for artificial reproduction are developing rapidly, and some protocols may be transferable to privately kept or endangered species. Reproductive tract disorders are rarely described; no bacterial or viral diseases are known that specifically target the amphibian reproductive system. Copyright © 2016 Elsevier Inc. All rights reserved.

The reproductive-cell cycle theory of aging: an update.

PubMed

Atwood, Craig S; Bowen, Richard L

2011-01-01

The Reproductive-Cell Cycle Theory posits that the hormones that regulate reproduction act in an antagonistic pleiotrophic manner to control aging via cell cycle signaling; promoting growth and development early in life in order to achieve reproduction, but later in life, in a futile attempt to maintain reproduction, become dysregulated and drive senescence. Since reproduction is the most important function of an organism from the perspective of the survival of the species, if reproductive-cell cycle signaling factors determine the rate of growth, determine the rate of development, determine the rate of reproduction, and determine the rate of senescence, then by definition they determine the rate of aging and thus lifespan. The theory is able to explain: 1) the simultaneous regulation of the rate of aging and reproduction as evidenced by the fact that environmental conditions and experimental interventions known to extend longevity are associated with decreased reproductive-cell cycle signaling factors, thereby slowing aging and preserving fertility in a hostile reproductive environment; 2) two phenomena that are closely related to species lifespan-the rate of growth and development and the ultimate size of the animal; 3). the apparent paradox that size is directly proportional to lifespan and inversely proportional to fertility between species but vice versa within a species; 4). how differing rates of reproduction between species is associated with differences in their lifespan; 5). why we develop aging-related diseases; and 6). an evolutionarily credible reason for why and how aging occurs-these hormones act in an antagonistic pleiotrophic manner via cell cycle signaling; promoting growth and development early in life in order to achieve reproduction, but later in life, in a futile attempt to maintain reproduction, become dysregulated and drive senescence (dyosis). In essence, the Reproductive-Cell Cycle Theory can explain aging in all sexually reproductive life forms. Published by Elsevier Inc.

Effect of elevation on distribution of female bats in the Black Hills, South Dakota

USGS Publications Warehouse

Cryan, P.M.; Bogan, M.A.; Altenbach, J.S.

2000-01-01

Presumably, reproductive female bats are more constrained by thermoregulatory and energy needs than are males and nonreproductive females. Constraints imposed on reproductive females may limit their geographic distribution relative to other bats. Such constraints likely increase with latitude and elevation. Males of 11 bat species that inhabit the Black Hills were captured more frequently than females, and reproductive females typically were encountered at low-elevational sites. To investigate the relationship between female distribution and elevation, we fitted a logistic regression model to evaluate the probability of reproductive-female capture as a function of elevation. Mist-net data from 1,197 captures of 7 species revealed that 75% of all captures were males. We found a significant inverse relationship between elevation and relative abundance of reproductive females. Relative abundance of reproductive females decreased as elevation increased. Reproductive females may be constrained from roosting and foraging in high-elevational habitats that impose thermoregulatory costs and decrease foraging efficiency. Failure to account for sex differences in distributional patterns along elevational gradients may significantly bias estimates of population size.

Biology of the invasive ascidian Ascidiella aspersa in its native habitat: Reproductive patterns and parasite load

NASA Astrophysics Data System (ADS)

Lynch, Sharon A.; Darmody, Grainne; O'Dwyer, Katie; Gallagher, Mary Catherine; Nolan, Sinead; McAllen, Rob; Culloty, Sarah C.

2016-11-01

The European sea squirt Ascidiella aspersa is a solitary tunicate native to the northeastern Atlantic, commonly found in shallow and sheltered marine ecosystems where it is capable of forming large clumps and outcompeting other invertebrate fauna at settlement. To date, there have been relatively few studies looking at the reproductive biology and health status of this invasive species. Between 2006 and 2010 sampling of a native population took place to investigate gametogenesis and reproductive cycle and to determine the impact of settlement depth on reproduction. In addition, parasite diversity and impact was assessed. A staging system to assess reproductive development was determined. The study highlighted that from year to year the tunicate could change its reproductive strategy from single sex to hermaphrodite, with spawning possible throughout the year. Depth did not impact on sex determination, however, gonad maturation and spawning occurred earlier in individuals in deeper waters compared to shallow depth and it also occurred later in A. aspersa at sites further away from the open sea. Four significant parasite groups including eugregarines, ciliates, trematodes and turbellarians were detected and prevalence of parasite infections increased in A. aspersa at sites with a reduced water flow rate. This study demonstrates the high biotic potential of this ascidian bioinvader to have a negative impact on native fauna in an introduced ecosystem, due to its highly efficient reproductive and resource allocation strategies. Artificial structures such as mooring lines can harbour large aggregations of A. aspersa, however, these manmade habitats may facilitate the colonisation and establishment of this invasive species in the benthos. Additionally, the parasite communities that A. aspersa harbour may also exacerbate its negative impact, both ecologically and economically, in an introduced area by possibly leading to the emergence of new disease in native species i.e. pathogen spillover.

Current issues in medically assisted reproduction and genetics in Europe: research, clinical practice, ethics, legal issues and policy. European Society of Human Genetics and European Society of Human Reproduction and Embryology.

PubMed

Harper, Joyce C; Geraedts, Joep; Borry, Pascal; Cornel, Martina C; Dondorp, Wybo; Gianaroli, Luca; Harton, Gary; Milachich, Tanya; Kääriäinen, Helena; Liebaers, Inge; Morris, Michael; Sequeiros, Jorge; Sermon, Karen; Shenfield, Françoise; Skirton, Heather; Soini, Sirpa; Spits, Claudia; Veiga, Anna; Vermeesch, Joris Robert; Viville, Stéphane; de Wert, Guido; Macek, Milan

2013-11-01

In March 2005, a group of experts from the European Society of Human Genetics and European Society of Human Reproduction and Embryology met to discuss the interface between genetics and assisted reproductive technology (ART), and published an extended background paper, recommendations and two Editorials. Seven years later, in March 2012, a follow-up interdisciplinary workshop was held, involving representatives of both professional societies, including experts from the European Union Eurogentest2 Coordination Action Project. The main goal of this meeting was to discuss developments at the interface between clinical genetics and ARTs. As more genetic causes of reproductive failure are now recognised and an increasing number of patients undergo testing of their genome before conception, either in regular health care or in the context of direct-to-consumer testing, the need for genetic counselling and preimplantation genetic diagnosis (PGD) may increase. Preimplantation genetic screening (PGS) thus far does not have evidence from randomised clinical trials to substantiate that the technique is both effective and efficient. Whole-genome sequencing may create greater challenges both in the technological and interpretational domains, and requires further reflection about the ethics of genetic testing in ART and PGD/PGS. Diagnostic laboratories should be reporting their results according to internationally accepted accreditation standards (International Standards Organisation - ISO 15189). Further studies are needed in order to address issues related to the impact of ART on epigenetic reprogramming of the early embryo. The legal landscape regarding assisted reproduction is evolving but still remains very heterogeneous and often contradictory. The lack of legal harmonisation and uneven access to infertility treatment and PGD/PGS fosters considerable cross-border reproductive care in Europe and beyond. The aim of this paper is to complement previous publications and provide an update of selected topics that have evolved since 2005.

Novel function of LHFPL2 in female and male distal reproductive tract development.

PubMed

Zhao, Fei; Zhou, Jun; Li, Rong; Dudley, Elizabeth A; Ye, Xiaoqin

2016-03-11

Congenital reproductive tract anomalies could impair fertility. Female and male reproductive tracts are developed from Müllerian ducts and Wolffian ducts, respectively, involving initiation, elongation and differentiation. Genetic basis solely for distal reproductive tract development is largely unknown. Lhfpl2 (lipoma HMGIC fusion partner-like 2) encodes a tetra-transmembrane protein with unknown functions. It is expressed in follicle cells of ovary and epithelial cells of reproductive tracts. A spontaneous point mutation of Lhfpl2 (LHFPL2(G102E)) leads to infertility in 100% female mice, which have normal ovarian development, ovulation, uterine development, and uterine response to exogenous estrogen stimulation, but abnormal upper longitudinal vaginal septum and lower vaginal agenesis. Infertility is also observed in ~70% mutant males, which have normal mating behavior and sperm counts, but abnormal distal vas deferens convolution resulting in complete and incomplete blockage of reproductive tract in infertile and fertile males, respectively. On embryonic day 15.5, mutant Müllerian ducts and Wolffian ducts have elongated but their duct tips are enlarged and fail to merge with the urogenital sinus. These findings provide a novel function of LHFPL2 and a novel genetic basis for distal reproductive tract development; they also emphasize the importance of an additional merging phase for proper reproductive tract development.

Reproductive effort in invasive and non-invasive Rubus.

PubMed

McDowell, Susan C; Turner, David P

2002-10-01

We quantified the physiological costs and the total amount of resources allocated to reproduction in two closely related species of Rubus, one of which is invasive. These two species share several morphological and life-history characteristics and grow together in the Pacific Northwestern United States. Reproductive effort was manipulated in canes of both species by removing flower buds. The non-invasive species, R. ursinus, exhibited significantly greater water stress in the reproductive canes, as indicated by lower leaf water potential (Ψ) and reduced stomatal conductance (g s ). This species also showed a reduction in leaf nitrogen concentration ([N]) associated with reproduction. Combined, these factors led to reduced photosynthesis (A) on a diurnal basis, lower water-use efficiency as inferred from δ 13 C, and reduced photosynthetic capacity. All of these effects were more pronounced during the fruiting stage than in the flowering stage. The invasive species, R. discolor, showed no changes in water stress, [N], δ 13 C, or A associated with reproduction. A model was used to estimate total gross photosynthesis (A gross ) for reproductive and non-reproductive canes of both species over cane lifetime. Reproduction was associated with a greater decline in A gross for the non-invasive R. ursinus than for the invasive R. discolor. Although R. discolor allocated more resources directly to flowers and fruit than R. ursinus, the invasive species had significantly lower reproductive effort, or total amount of resources diverted from vegetative activity to reproduction, than the non-invasive species. By minimizing the reduction of photosynthesis associated with reproduction, this invasive species may be able to minimize the trade-offs commonly associated with reproduction.

Sociality, mating system and reproductive skew in marmots: evidence and hypotheses.

PubMed

Allainé

2000-10-05

Marmot species exhibit a great diversity of social structure, mating systems and reproductive skew. In particular, among the social species (i.e. all except Marmota monax), the yellow-bellied marmot appears quite different from the others. The yellow-bellied marmot is primarily polygynous with an intermediate level of sociality and low reproductive skew among females. In contrast, all other social marmot species are mainly monogamous, highly social and with marked reproductive skew among females. To understand the evolution of this difference in reproductive skew, I examined four possible explanations identified from reproductive skew theory. From the literature, I then reviewed evidence to investigate if marmot species differ in: (1) the ability of dominants to control the reproduction of subordinates; (2) the degree of relatedness between group members; (3) the benefit for subordinates of remaining in the social group; and (4) the benefit for dominants of retaining subordinates. I found that the optimal skew hypothesis may apply for both sets of species. I suggest that yellow-bellied marmot females may benefit from retaining subordinate females and in return have to concede them reproduction. On the contrary, monogamous marmot species may gain by suppressing the reproduction of subordinate females to maximise the efficiency of social thermoregulation, even at the risk of departure of subordinate females from the family group. Finally, I discuss scenarios for the simultaneous evolution of sociality, monogamy and reproductive skew in marmots.

Nanopurification of semen improves AI pregnancy rates in beef cattle

USDA-ARS?s Scientific Manuscript database

Reproductive efficiency is several times more important than any other factor affecting economic efficiency in beef production. Multiple studies have been conducted to improve fertility of beef cows, but few studies have been conducted to improve fertility in sires. Also, with current improvements...

Effect of reproductive disorders on productivity and reproductive efficiency of dromedary she-camels in relation to cytokine concentration.

PubMed

El-Malky, O M; Mostafa, T H; Abd El-Salaam, A M; Ayyat, M S

2018-06-01

This experiment was conducted to study the effect of reproductive disorders on reproductive efficiency and milk production in relation with pro-inflammatory cytokines in dromedary she-camels. Total of 20 late pregnant Maghrabi she-camels, aging 6-9 years, weighing 420-550 kg, and between the second and third parities were divided into two groups. Animals in the first group (n = 12) showed normal reproductive status (G 1 ) at parturition, while those in the second one (n = 8) were suffered from reproductive disorders after parturition (G 2 ). Results showed that during pre-partum, red blood cells (RBCs) count decreased (P ≤ 0.05), while white blood cells (WBCs), packed cell volume (PCV) value, and neutrophils percentage increased (P ≤ 0.05) in G 2 than in G 1 . Percentages of monocytes, basophils, and eosinophils as well as hemoglobin concentration did not differ significantly (P ≥ 0.05) in G1 and G2. During postpartum period, the same results were noticed in addition to increase (P ≤ 0.05) in eosinophil and decrease (P ≤ 0.05) in basophils percentages. During prepartum period, concentration of total proteins, albumin (AL) and IGF-1decreased (P ≤ 0.05), cholesterol concentration, and activity of AST and ALT were higher (P ≤ 0.05) in G 2 than in G 1 . Globulin (GL), AL: GL ratio, glucose, urea-N, creatinine, and triglyceride concentrations did not differ significantly in G 1 and G 2 . During postpartum period, the same results were noticed with decrease (P ≤ 0.05) in GL and glucose concentrations in G 2 as compared to G 1 . Concentration of all pro-inflammatory cytokines, including IL-6, IL-10, and IFN-γ, was higher (P ≤ 0.05) in G 2 than in G 1 at different peri-parturient times. Milk yield, days in milk, protein and lactose percentages, and IgG concentration were higher (P ≤ 0.05) in G 1 than in G 2 . Fat, total solids, solid non-fat, and ash percentages did not show any significant differences between both groups. Reproductive traits, including length of estrous cycle, duration of estrous period, number of services/conception, gestation period, days open, and conception rate, were higher (P < 0.05) in G 1 than in G 2 . From the present study can be concluded that pro-inflammatory cytokines may be a necessary test for the early diagnosis to prevent related disease in dromedary camels suffering from reproductive disorders. This study indicated strong relationship between hematological parameters and concentration of blood biochemicals and cytokines with reproductive efficiency in camels, which may be helpful in elucidating the adverse effects associated with reproductive disorders.

24 CFR 3500.9 - Reproduction of settlement statements.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Reproduction of settlement... HOUSING AND URBAN DEVELOPMENT REAL ESTATE SETTLEMENT PROCEDURES ACT § 3500.9 Reproduction of settlement... in sections F and H, respectively. (3) Reproduction of the HUD-1 must conform to the terminology...

A New Curve of Critical Nitrogen Concentration Based on Spike Dry Matter for Winter Wheat in Eastern China

PubMed Central

Zhao, Ben; Ata-UI-Karim, Syed Tahir; Yao, Xia; Tian, YongChao; Cao, WeiXing; Zhu, Yan; Liu, XiaoJun

2016-01-01

Diagnosing the status of crop nitrogen (N) helps to optimize crop yield, improve N use efficiency, and reduce the risk of environmental pollution. The objectives of the present study were to develop a critical N (Nc) dilution curve for winter wheat (based on spike dry matter [SDM] during the reproductive growth period), to compare this curve with the existing Nc dilution curve (based on plant dry matter [DM] of winter wheat), and to explore its ability to reliably estimate the N status of winter wheat. Four field experiments, using varied N fertilizer rates (0–375 kg ha-1) and six cultivars (Yangmai16, Ningmai13, Ningmai9, Aikang58, Yangmai12, Huaimai 17), were conducted in the Jiangsu province of eastern China. Twenty plants from each plot were sampled to determine the SDM and spike N concentration (SNC) during the reproductive growth period. The spike Nc curve was described by Nc = 2.85×SDM-0.17, with SDM ranging from 0.752 to 7.233 t ha-1. The newly developed curve was lower than the Nc curve based on plant DM. The N nutrition index (NNI) for spike dry matter ranged from 0.62 to 1.1 during the reproductive growth period across the seasons. Relative yield (RY) increased with increasing NNI; however, when NNI was greater than 0.96, RY plateaued and remained stable. The spike Nc dilution curve can be used to correctly identify the N nutrition status of winter wheat to support N management during the reproductive growth period for winter wheat in eastern China. PMID:27732634

Phenoptosis in arthropods and immortality of social insects.

PubMed

Kartsev, V M

2014-10-01

In general, there are no drastic differences in phenoptosis patterns in plant and animal organisms. However, there are some specific features characteristic for insects and other arthropods: 1) their development includes metamorphosis with different biochemical laws at consecutive developmental stages; 2) arthropods can reduce or stop development and aging when in a state of diapause or temporal cold immobility; 3) their life cycle often correlates with seasonal changes of surroundings; 4) polymorphism is widespread - conspecifics differ by their lifespans and phenoptosis features; 5) lifespan-related sexual dimorphism is common; 6) significant situational plasticity of life cycle organization is an important feature; for example, the German wasp (Paravespula germanica) is obligatorily univoltine in the temperate zone, while in tropical regions its lifespan increases and leads to repeated reproduction; 7) life cycles of closely related species may differ significantly, for example, in contrast to German wasp, some tropical hornets (Vespa) have only one reproduction period. Surprisingly, many insect species have been shown to be subjected to gradual aging and phenoptosis, like the highest mammals. However, queens of social insects and some long-lived arachnids can apparently be considered non-aging organisms. In some species, lifespan is limited to one season, while others live much longer or shorter. Cases of one-time reproduction are rather rare. Aphagia is common in insects (over 10,000 species). Cannibalism is an important mortality factor in insects as well as in spiders. In social insects, which exist only in colonies (families), the lifetime of a colony can be virtually unlimited. However, in case of some species the developmental cycle and death of a colony after its completion are predetermined. Most likely, natural selection in insects does not lengthen individual lifespan, but favors increase in reproduction efficiency based on fast succession of generations leading to increased evolvability.

Effects of evaporative cooling on reproductive performance and milk production of dairy cows in hot wet conditions

NASA Astrophysics Data System (ADS)

Khongdee, S.; Chaiyabutr, N.; Hinch, G.; Markvichitr, K.; Vajrabukka, C.

2006-05-01

Fourteen animals of second and third lactation of Thai Friesian crossbred cows (87.5% Friesian × 12.5% Bos indicus) located at Sakol Nakhon Research and Breeding Centre, Department of Livestock Development, Ministry of Agriculture and Cooperatives, were divided randomly into two groups of seven each to evaluate the effects of evaporative cooling on reproductive and physiological traits under hot, humid conditions. Results indicated that installation of evaporating cooling in the open shed gave a further improvement in ameliorating heat stress in dairy cows in hot-wet environments by utilising the low humidity conditions that naturally occur during the day. The cows housed in an evaporatively cooled environment had both a rectal temperature and respiration rate (39.09°C, 61.39 breaths/min, respectively) significantly lower than that of the non-cooled cows (41.21°C; 86.87 breaths/min). The former group also had higher milk yield and more efficient reproductive performance (pregnancy rate and reduced days open) than the latter group. It is suggested that the non-evaporatively cooled cows did not gain benefit from the naturally lower heat stress during night time.

Reproduction and advances in reproductive studies in carnivores.

PubMed

Jewgenow, Katarina; Songsasen, Nucharin

2014-01-01

Reproductive mechanisms are extraordinarily diverse among species, even within the same phylogenetic clade. Due to this, it has been difficult to directly apply reproductive technologies developed in human and livestock to genetically manage ex situ wildlife, including carnivores. To date, more common, closely related species, e.g., domestic cats, dogs and ferrets have served as valuable models for developing reproductive technologies for managing rare, endangered carnivores. Artificial insemination and sperm cryopreservation have already been successfully used to manage ex situ populations in some carnivore species, such as the black-footed ferret, cheetah and giant panda. However, technologies aiming at preserving genetics of valuable females have not been fully developed in carnivores, due to the lack of fundamental knowledge about reproductive anatomy and physiology, gamete development, embryogenesis and cryopreservation. The present chapter is divided into two parts. The first part focuses on current knowledge about carnivore reproduction, with emphasis on species diversity in reproductive mechanisms. The second part highlights the progress in reproductive science and related technologies made during the last decade. In addition, we provide examples of how reproductive technologies can contribute to carnivore management and conservation. Although carnivores are comprised of 19 families, we will only focus our attention on four taxonomic groups, including felids, canids, ursids and mustelids.

Effect of feed flushing during summer season on growth, reproductive performance and blood metabolites in Malpura ewes under semiarid tropical environment.

PubMed

Naqvi, Syed Mohammad Khursheed; Sejian, Veerasamy; Karim, Shaikh Abdul

2013-01-01

Feed scarcity during hot summer months is one of the major predisposing factors for low reproductive efficiency of livestock reared in hot semiarid environment. A study was conducted to assess the effect of concentrate supplementation during summer months on growth, reproductive performance, and blood metabolites in Malpura ewes. Twenty adult Malpura ewes were used in the present study. The ewes were divided into two groups viz, group 1 (n = 10; control) and group 2 (n = 10; concentrate supplementation). The study was conducted for a period of 35 days covering two estrus cycles. In the first cycle, only PGF(2α) was given to all ewes, while in second cycle, all ewes were synchronized for estrus using progesterone-impregnated intravaginal sponges and pregnant mare serum gonadotropin. The animals were allowed for grazing for 8-10 h per day. Apart from grazing, group 2 ewes were supplemented with concentrate mixture at 1.5 % of body weight. Concentrate supplementation had significant influence on body weight, ADG, estrus percentage, estrus duration, onset of estrus, ovulation response, plasma glucose, total protein, and urea. The present study reveals that ewes supplemented with concentrate mixture at 1.5 % of body weights during summer season significantly influenced the growth and reproductive performance of Malpura ewes. Further, the study signifies the importance of providing additional feed supplementation to ewes kept grazing under the conditions of a hot, semiarid environment to improve their reproductive efficiency.

Quantitative variation in water-use efficiency across water regimes and its relationship with circadian, vegetative, reproductive, and leaf gas-exchange traits.

PubMed

Edwards, Christine E; Ewers, Brent E; McClung, C Robertson; Lou, Ping; Weinig, Cynthia

2012-05-01

Drought limits light harvesting, resulting in lower plant growth and reproduction. One trait important for plant drought response is water-use efficiency (WUE). We investigated (1) how the joint genetic architecture of WUE, reproductive characters, and vegetative traits changed across drought and well-watered conditions, (2) whether traits with distinct developmental bases (e.g. leaf gas exchange versus reproduction) differed in the environmental sensitivity of their genetic architecture, and (3) whether quantitative variation in circadian period was related to drought response in Brassica rapa. Overall, WUE increased in drought, primarily because stomatal conductance, and thus water loss, declined more than carbon fixation. Genotypes with the highest WUE in drought expressed the lowest WUE in well-watered conditions, and had the largest vegetative and floral organs in both treatments. Thus, large changes in WUE enabled some genotypes to approach vegetative and reproductive trait optima across environments. The genetic architecture differed for gas-exchange and vegetative traits across drought and well-watered conditions, but not for floral traits. Correlations between circadian and leaf gas-exchange traits were significant but did not vary across treatments, indicating that circadian period affects physiological function regardless of water availability. These results suggest that WUE is important for drought tolerance in Brassica rapa and that artificial selection for increased WUE in drought will not result in maladaptive expression of other traits that are correlated with WUE.

Breeding and mass scale rearing of clownfish Amphiprion percula: feeding and rearing in brackishwater

NASA Astrophysics Data System (ADS)

Dhaneesh, Kottila Veettil; Ajith Kumar, Thipramalai Thankappan; Swagat, Ghosh; Balasubramanian, Thangavel

2012-07-01

Breeding and mass scale larval rearing of clownfish Amphiprion percula is very limited in brackishwater. We designed an indoor program of A. percula culture in brackishwater with a salinity of 24±1, during which the impacts of feed type, water temperature, and light intensity, on the efficiency of its reproduction, were revealed. The fish were accommodated along with sea anemones in fibre glass tanks to determine the influence of brooder diet on breeding efficiency. Higher reproductive efficiency [number of eggs laid (276 ± 22.3 eggs)] was observed when fish were fed live Acetes sp. rather than clam (204 ± 16.4 eggs), trash fish (155 ± 12 eggs) and formulated feed (110 ± 10 eggs). The spawning rate was increased during September and October (water temperature, 28.74 ± 0.55°C) on average of 2.4 spawning per month; and low spawning rate was in January (water temperature, 24.55 ± 0.45°C) on average of 1 spawning per month. Among three light intensities (100, 500, and 900 lx) set to evaluate larval survival rate, larvae showed the highest survival rate (65.5%) at 900 lx. The breeding method specifically in brackishwater developed in the present study is a new approach, will help the people from the regions of estuary and backwater to enhance their livelihood and it will lead to reduce the exploitation from the wild habitat.

Floral traits driving reproductive isolation of two co-flowering taxa that share vertebrate pollinators

PubMed Central

Queiroz, Joel A.; Quirino, Zelma G. M.; Machado, Isabel C.

2015-01-01

Floral attributes evolve in response to frequent and efficient pollinators, which are potentially important drivers of floral diversification and reproductive isolation. In this context, we asked, how do flowers evolve in a bat–hummingbird pollination system? Hence, we investigated the pollination ecology of two co-flowering Ipomoea taxa (I. marcellia and I. aff. marcellia) pollinated by bats and hummingbirds, and factors favouring reproductive isolation and pollinator sharing in these plants. To identify the most important drivers of reproductive isolation, we compared the flowers of the two Ipomoea taxa in terms of morphometry, anthesis and nectar production. Pollinator services were assessed using frequency of visits, fruit set and the number of seeds per fruit after visits. The studied Ipomoea taxa differed in corolla size and width, beginning and duration of anthesis, and nectar attributes. However, they shared the same diurnal and nocturnal visitors. The hummingbird Heliomaster squamosus was more frequent in I. marcellia (1.90 visits h−1) than in I. aff. marcellia (0.57 visits h−1), whereas glossophagine bats showed similar visit rates in both taxa (I. marcellia: 0.57 visits h−1 and I. aff. marcellia: 0.64 visits h−1). Bat pollination was more efficient in I. aff. marcellia, whereas pollination by hummingbirds was more efficient in I. marcellia. Differences in floral attributes between Ipomoea taxa, especially related to the anthesis period, length of floral parts and floral arrangement in the inflorescence, favour reproductive isolation from congeners through differential pollen placement on pollinators. This bat–hummingbird pollination system seems to be advantageous in the study area, where the availability of pollinators and floral resources changes considerably throughout the year, mainly as a result of rainfall seasonality. This interaction is beneficial for both sides, as it maximizes the number of potential pollen vectors for plants and resource availability for pollinators. PMID:26558704

Temporal Feeding Pattern May Influence Reproduction Efficiency, the Example of Breeding Mares

PubMed Central

Benhajali, Haifa; Ezzaouia, Mohammed; Lunel, Christophe; Charfi, Faouzia; Hausberger, Martine

2013-01-01

Discomfort in farm animals may be induced by inappropriate types or timing of food supplies. Thus, time restriction of meals and lack of roughage have been shown to be one source of emergence of oral stereotypies and abnormal behaviour in horses which have evolved to eat high-fibre diets in small amounts over long periods of time. This feeding pattern is often altered in domestic environment where horses are often fed low fibre meals that can be rapidly consumed. This study aimed at determining the effect of the temporal pattern of feeding on reproductive efficiency of breeding mares, One hundred Arab breeding mares were divided into two groups that differed only in the temporal pattern of roughage availability: only at night for the standard feeding pattern group (SFP mares), night and day for the “continuous feeding” group (CF mares). The total amount of roughage provided was the same as the CF mares received half of the hay during the day while in paddock (haynets). Mares were tested for oestrus detection by teasing with one stallion and were then examined clinically by rectal palpations and ultrasound before being mated naturally or inseminated by fresh or frozen semen. Multivariate logistic regression was used to analyse data. The treatment affected significantly the reproductive efficiency of the mares with fewer oestrus abnormalities (p = 0.0002) and more fertility (p = 0.024) in CF mares (conception rate = 81% versus 55% in SFP mares). Ensuring semi-continous feeding by providing roughage may be a way of fulfilling the basic physiological needs of the horses' digestive system, reducing stress and associated inhibitors of reproduction. To our knowledge, this study provides the first evidence of an impact of temporal feeding patterns on reproductive success in a Mammal. Temporal patterns of feeding may be a major and underestimated factor in breeding. PMID:24098636

New commercial opportunities for advanced reproductive technologies in horses, wildlife, and companion animals.

PubMed

Long, C R; Walker, S C; Tang, R T; Westhusin, M E

2003-01-01

As advanced reproductive technologies become more efficient and repeatable in livestock and laboratory species, new opportunities will evolve to apply these techniques to alternative and non-traditional species. This will result in new markets requiring unique business models that address issues of animal welfare and consumer acceptance on a much different level than the livestock sector. Advanced reproductive technologies and genetic engineering will be applied to each species in innovative ways to provide breeders more alternatives for the preservation and propagation of elite animals in each sector. The commercialization of advanced reproductive techniques in these niche markets should be considered a useful tool for conservation of genetic material from endangered or unique animals as well as production of biomedical models of human disease. Copyright 2002 Elsevier Science Inc.

Donor cell differentiation, reprogramming, and cloning efficiency: elusive or illusive correlation?

PubMed

Oback, B; Wells, D N

2007-05-01

Compared to other assisted reproductive technologies, mammalian nuclear transfer (NT) cloning is inefficient in generating viable offspring. It has been postulated that nuclear reprogramming and cloning efficiency can be increased by choosing less differentiated cell types as nuclear donors. This hypothesis is mainly supported by comparative mouse cloning experiments using early blastomeres, embryonic stem (ES) cells, and terminally differentiated somatic donor cells. We have re-evaluated these comparisons, taking into account different NT procedures, the use of donor cells from different genetic backgrounds, sex, cell cycle stages, and the lack of robust statistical significance when post-blastocyst development is compared. We argue that while the reprogrammability of early blastomeres appears to be much higher than that of somatic cells, it has so far not been conclusively determined whether differentiation status affects cloning efficiency within somatic donor cell lineages. Copyright (c) 2006 Wiley-Liss, Inc.

Leptospirosis is strongly associated to estrus repetition on cattle.

PubMed

Libonati, H A; Santos, G B; Souza, G N; Brandão, F Z; Lilenbaum, W

2018-05-02

Although prevalent, the exact impact of infectious diseases on reproductive failures remains to be determined. Among them, leptospirosis has commonly been reported as cause of abortions on outbreaks. Nevertheless, the majority of the animals present a chronic, silent form of the disease, which is characterized by low reproductive efficiency and is frequently neglected. In that context, we conducted a study that aims to estimate the impact of chronic leptospirosis on reproductive disorders on cattle. A total of 25 different dairy herds with history of reproductive losses from Rio de Janeiro, Brazil, were selected. From each herd, a questionnaire was applied and sera from 20 cows were randomly tested for leptospirosis (totaling 500 cows). Chi-square was performed to estimate the association of seroreactivity with reproductive disorders. A total of 32% of the herds were positive, all of them against serogroup Sejroe. Estrus repetition was the most important reported reproductive problem and it was strongly associated to seroreactivity against leptospirosis. Besides, specific vaccination against leptospirosis was an important protection factor against that disorder. In conclusion, control programs including, but not limited to, vaccines must be implemented on those herds in order to reduce reproductive losses, particularly estrus repetition.

The economic impact of assisted reproductive technology: a review of selected developed countries.

PubMed

Chambers, Georgina M; Sullivan, Elizabeth A; Ishihara, Osamu; Chapman, Michael G; Adamson, G David

2009-06-01

To compare regulatory and economic aspects of assisted reproductive technologies (ART) in developed countries. Comparative policy and economic analysis. Couples undergoing ART treatment in the United States, Canada, United Kingdom, Scandinavia, Japan, and Australia. Description of regulatory and financing arrangements, cycle costs, cost-effectiveness ratios, total expenditure, utilization, and price elasticity. Regulation and financing of ART share few general characteristics in developed countries. The cost of treatment reflects the costliness of the underlying healthcare system rather than the regulatory or funding environment. The cost (in 2006 United States dollars) of a standard IVF cycle ranged from $12,513 in the United States to $3,956 in Japan. The cost per live birth was highest in the United States and United Kingdom ($41,132 and $40,364, respectively) and lowest in Scandinavia and Japan ($24,485 and $24,329, respectively). The cost of an IVF cycle after government subsidization ranged from 50% of annual disposable income in the United States to 6% in Australia. The cost of ART treatment did not exceed 0.25% of total healthcare expenditure in any country. Australia and Scandinavia were the only country/region to reach levels of utilization approximating demand, with North America meeting only 24% of estimated demand. Demand displayed variable price elasticity. Assisted reproductive technology is expensive from a patient perspective but not from a societal perspective. Only countries with funding arrangements that minimize out-of-pocket expenses met expected demand. Funding mechanisms should maximize efficiency and equity of access while minimizing the potential harm from multiple births.

Ecotoxicological efficiency of advanced ozonation processes with TiO2 and black light used in the degradation of carbamazepine.

PubMed

Oropesa, Ana Lourdes; Beltrán, Fernando Juan; Floro, António Miguel; Sagasti, Juan José Pérez; Palma, Patrícia

2018-01-01

The aim of the present study was to evaluate the ecotoxicological efficiency of two advanced ozonation processes (AOzPs), the catalytic ozonation (O 3 /TiO 2 ) and the photocatalytic ozonation (O 3 /TiO 2 /black light), in the remotion of carbamazepine. The ecotoxicological efficiency was assessed through the use of lethal and sublethal assays with species Vibrio fischeri and Daphnia magna. Results demonstrated that the AOzPs presented an efficiency of carbamazepine removal higher than 99% (carbamazepine < 2 μg/L) after 12 min of treatment. Relatively to ecotoxicological evaluation, application of acute assay to V. fischeri and chronic assay to D. magna allowed us to highlight that these technologies may form some transformation products that induce toxicity in the bacteria and the crustacean, once these organisms exposed to the undiluted solutions (100%) showed a decrease in the bioluminescence (vibrio) and end up dying before and during the first reproduction (daphnia). Despite that, when the chronic results obtained with the diluted solutions (50 and 25%; important to assess a more realistic scenario considering the dilution factor at the environment) were analyzed, no mortality at the mothers was observed. Compared to a carbamazepine solution (200 μg/L), diluted solutions improved of the reproduction parameters, and no toxic effects in the juvenoid system and in the embryonic development were observed. Relatively to the ecdysteroid effect of a carbamazepine solution (200 μg/L), only the photocatalytic ozonation treatment was able to remove the action of the drug. These results highlight the importance of complementing chemical analysis with ecotoxicological bioassays to assess the best technology to improve the surface water and effluent quality.

Evaluation of the impact of the voucher and accreditation approach on improving reproductive behaviors and status in Cambodia

PubMed Central

2011-01-01

Background Cost of delivering reproductive health services to low income populations will always require total or partial subsidization by government and/or development partners. Broadly termed "demand-side financing" or "output-based aid", these strategies include a range of interventions that channel government or donor subsidies to the user rather than the service provider. Initial pilot assessments of reproductive health voucher programs suggest that they can increase access, reduce inequities, and enhance program efficiency and service quality. However, there is a paucity of evidence describing how these programs function in different settings for various reproductive health services. Methods/Design Population Council, funded by the Bill and Melinda Gates Foundation, intends to generate evidence around the "voucher and accreditation" approaches to improving the reproductive health of low-income women in Cambodia. The study comprises of four populations: facilities, providers, women of reproductive age using facilities, and women and men who have been pregnant and/or used family planning within the previous 12 months. The study will be carried out in a sample of 20 health facilities that are accredited to provide maternal and newborn health and family planning services to women holding vouchers from operational districts in three provinces: Kampong Thom, Kampot and Prey Veng and a matched sample of non-accredited facilities in three other provinces. Health facility assessments will be conducted at baseline and endline to track temporal changes in quality-of-care, client out-of-pocket costs, and utilization. Facility inventories, structured observations, and client exit interviews will be used to collect comparable data across facilities. Health providers will also be interviewed and observed providing care. A population survey of about 3000 respondents will also be conducted in areas where vouchers are distributed and similar non-voucher locations. Discussion A quasi-experimental study will investigate the impact of the voucher approach on improving reproductive health behaviors, reproductive health status and reducing inequities at the population level and assess effects on access, equity and quality of care at the facility level. If the voucher scheme in Cambodia is found effective, it may help other countries adopt this approach for improving utilization and access to reproductive health and family planning services. PMID:21864405

Node-controlled allocation of mineral elements in Poaceae.

PubMed

Yamaji, Naoki; Ma, Jian Feng

2017-10-01

Mineral elements taken up by the roots will be delivered to different organs and tissues depending on their requirements. In Poaceae, this selective distribution is mainly mediated in the nodes, which have highly developed and fully organized vascular systems. Inter-vascular transfer of mineral elements from enlarged vascular bundles to diffuse vascular bundles is required for their preferential distribution to developing tissues and reproductive organs. A number of transporters involved in this inter-vascular transfer processes have been identified mainly in rice. They are localized at the different cell layers and form an efficient machinery within the node. Furthermore, some these transporters show rapid response to the environmental changes of mineral elements at the protein level. In addition to the node-based transporters, distinct nodal structures including enlarged xylem area, folded plasma membrane of xylem transfer cells and presence of an apoplastic barrier are also required for the efficient inter-vascular transfer. Manipulation of node-based transporters will provide a novel breeding target to improve nutrient use efficiency, productivity, nutritional value and safety in cereal crops. Copyright © 2017 Elsevier Ltd. All rights reserved.

Panmictic and Clonal Evolution on a Single Patchy Resource Produces Polymorphic Foraging Guilds

PubMed Central

Getz, Wayne M.; Salter, Richard; Lyons, Andrew J.; Sippl-Swezey, Nicolas

2015-01-01

We develop a stochastic, agent-based model to study how genetic traits and experiential changes in the state of agents and available resources influence individuals’ foraging and movement behaviors. These behaviors are manifest as decisions on when to stay and exploit a current resource patch or move to a particular neighboring patch, based on information of the resource qualities of the patches and the anticipated level of intraspecific competition within patches. We use a genetic algorithm approach and an individual’s biomass as a fitness surrogate to explore the foraging strategy diversity of evolving guilds under clonal versus hermaphroditic sexual reproduction. We first present the resource exploitation processes, movement on cellular arrays, and genetic algorithm components of the model. We then discuss their implementation on the Nova software platform. This platform seamlessly combines the dynamical systems modeling of consumer-resource interactions with agent-based modeling of individuals moving over a landscapes, using an architecture that lays transparent the following four hierarchical simulation levels: 1.) within-patch consumer-resource dynamics, 2.) within-generation movement and competition mitigation processes, 3.) across-generation evolutionary processes, and 4.) multiple runs to generate the statistics needed for comparative analyses. The focus of our analysis is on the question of how the biomass production efficiency and the diversity of guilds of foraging strategy types, exploiting resources over a patchy landscape, evolve under clonal versus random hermaphroditic sexual reproduction. Our results indicate greater biomass production efficiency under clonal reproduction only at higher population densities, and demonstrate that polymorphisms evolve and are maintained under random mating systems. The latter result questions the notion that some type of associative mating structure is needed to maintain genetic polymorphisms among individuals exploiting a common patchy resource on an otherwise spatially homogeneous landscape. PMID:26274613

Reproductive seasonality in the mare: neuroendocrine basis and pharmacologic control.

PubMed

Williams, G L; Thorson, J F; Prezotto, L D; Velez, I C; Cardoso, R C; Amstalden, M

2012-08-01

Reproductive seasonality in the mare is characterized by a marked decline in adenohypophyseal synthesis and secretion of LH beginning near the autumnal equinox. Thus, ovarian cycles have ceased in most mares by the time of the winter solstice. Endogenous reproductive rhythms in seasonal species are entrained or synchronized as a result of periodic environmental cues. In the horse, this cue is primarily day length. Hence, supplemental lighting schemes have been used managerially for decades to modify the annual timing of reproduction in the mare. Although a full characterization of the cellular and molecular bases of seasonal rhythms has not been realized in any species, many of their synaptic and humoral signaling pathways have been defined. In the mare, neuroendocrine-related studies have focused primarily on the roles of GnRH and interneuronal signaling pathways that subserve the GnRH system in the regulatory cascade. Recent studies have considered the role of a newly discovered neuropeptide, RF-related peptide 3 that could function to inhibit GnRH secretion or gonadotrope responsiveness. Although results that used native peptide sequences have been negative in the mare and mixed in all mammalian females, new studies that used an RFRP3 antagonist (RF9) in sheep are encouraging. Importantly, despite continuing deficits in some fundamental areas, the knowledge required to control seasonal anovulation pharmacologically has been available for >20 yr. Specifically, the continuous infusion of native GnRH is both reliable and efficient for accelerating reproductive transition and is uniquely applicable to the horse. However, its practical exploitation continues to await the development of a commercially acceptable delivery vehicle. Copyright © 2012 Elsevier Inc. All rights reserved.

ESHRE's good practice guide for cross-border reproductive care for centers and practitioners.

PubMed

Shenfield, F; Pennings, G; De Mouzon, J; Ferraretti, A P; Goossens, V

2011-07-01

This paper outlines ESHRE's guidance for centers and physicians providing fertility treatment to foreign patients. This guide aims to ensure high-quality and safe assisted reproduction treatment, taking into account the patients, their future child and the interests of third-party collaborators such as gametes donors and surrogates. This is achieved by including considerations of equity, safety, efficiency, effectiveness (including evidence-based care), timeliness and patient centeredness.

Current issues in medically assisted reproduction and genetics in Europe: research, clinical practice, ethics, legal issues and policy

PubMed Central

Harper, Joyce C; Geraedts, Joep; Borry, Pascal; Cornel, Martina C; Dondorp, Wybo; Gianaroli, Luca; Harton, Gary; Milachich, Tanya; Kääriäinen, Helena; Liebaers, Inge; Morris, Michael; Sequeiros, Jorge; Sermon, Karen; Shenfield, Françoise; Skirton, Heather; Soini, Sirpa; Spits, Claudia; Veiga, Anna; Vermeesch, Joris Robert; Viville, Stéphane; de Wert, Guido; Macek, Milan

2013-01-01

In March 2005, a group of experts from the European Society of Human Genetics and European Society of Human Reproduction and Embryology met to discuss the interface between genetics and assisted reproductive technology (ART), and published an extended background paper, recommendations and two Editorials. Seven years later, in March 2012, a follow-up interdisciplinary workshop was held, involving representatives of both professional societies, including experts from the European Union Eurogentest2 Coordination Action Project. The main goal of this meeting was to discuss developments at the interface between clinical genetics and ARTs. As more genetic causes of reproductive failure are now recognised and an increasing number of patients undergo testing of their genome before conception, either in regular health care or in the context of direct-to-consumer testing, the need for genetic counselling and preimplantation genetic diagnosis (PGD) may increase. Preimplantation genetic screening (PGS) thus far does not have evidence from randomised clinical trials to substantiate that the technique is both effective and efficient. Whole-genome sequencing may create greater challenges both in the technological and interpretational domains, and requires further reflection about the ethics of genetic testing in ART and PGD/PGS. Diagnostic laboratories should be reporting their results according to internationally accepted accreditation standards (International Standards Organisation – ISO 15189). Further studies are needed in order to address issues related to the impact of ART on epigenetic reprogramming of the early embryo. The legal landscape regarding assisted reproduction is evolving but still remains very heterogeneous and often contradictory. The lack of legal harmonisation and uneven access to infertility treatment and PGD/PGS fosters considerable cross-border reproductive care in Europe and beyond. The aim of this paper is to complement previous publications and provide an update of selected topics that have evolved since 2005. PMID:24225486

Investigation of infectious reproductive pathogens of large ruminants: Are neosporosis, brucellosis, leptospirosis and BVDV of relevance in Lao PDR?

PubMed

Olmo, L; Dye, M T; Reichel, M P; Young, J R; Nampanya, S; Khounsy, S; Thomson, P C; Windsor, P A; Bush, R D

2018-01-01

N. caninum, bovine viral diarrhoea virus, Brucella abortus and Leptospira interrogans serovar Hardjo are globally significant reproductive pathogens that cause abortion and reproductive loss in large ruminants. Prevalence information is lacking in Lao People's Democratic Republic (Laos) despite the poor reproductive performance of cattle and buffalo. Serological examination of frozen cattle (n=90) and buffalo (n=61) sera by commercially available enzyme-linked immunosorbent assays provided the first reported screening of some of these pathogens in Laos. Seroprevalence differed amongst these large ruminant species, with N. caninum, BVDV and L. interrogans serovar Hardjo antibodies found in 68.9% (95% CI±11.6), 4.9% (95% CI±5.4) and 3.3% (95% CI±4.5) of buffalo sera, respectively, and in 7.8% (95% CI±5.5), 10.0% (95% CI±6.2) and 22.2% (95% CI±8.6) of cattle sera, respectively. Buffalo sera had a significantly higher seroprevalence of N. caninum compared to cattle (p<0.001) and cattle sera had a significantly higher seroprevalence of L. interrogans serovar Hardjo compared to buffalo (p=0.003). Variability was also observed across provinces for N. caninum in buffalo (p=0.007) and for L. interrogans serovar Hardjo in cattle (p=0.071), suggesting provincial risk factors conducive to pathogen transmission. BVDV and N. caninum seropositivity were negatively associated in buffalo (p=0.018) and cattle (p=0.003). In buffalo, L. interrogans serovar Hardjo and BVDV seropositivity were associated (p=0.035, p=0.039). The identification of antibodies against three major abortifacient pathogens in Laos prompts further research to determine if infection is associated with low reproductive efficiency and the risk factors for infection. This is needed for the development of evidence based prevention strategies for improved large ruminant reproductive management among smallholders in Laos. Copyright © 2017 Elsevier B.V. All rights reserved.

Fetal programming of sexual development and reproductive function.

PubMed

Zambrano, Elena; Guzmán, Carolina; Rodríguez-González, Guadalupe L; Durand-Carbajal, Marta; Nathanielsz, Peter W

2014-01-25

The recent growth of interest in developmental programming of physiological systems has generally focused on the cardiovascular system (especially hypertension) and predisposition to metabolic dysfunction (mainly obesity and diabetes). However, it is now clear that the full range of altered offspring phenotypes includes impaired reproductive function. In rats, sheep and nonhuman primates, reproductive capacity is altered by challenges experienced during critical periods of development. This review will examine available experimental evidence across commonly studied experimental species for developmental programming of female and male reproductive function throughout an individual's life-course. It is necessary to consider events that occur during fetal development, early neonatal life and prior to and during puberty, during active reproductive life and aging as reproductive performance declines. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

CRITICAL WINDOWS FOR REPRODUCTIVE HEALTH IN CHILDREN AND ADOLESCENTS

EPA Science Inventory

This workgroup report addresses the central question: what are the critical windows during development (pre-conception through puberty) when exposure to xenobiotics may have the greatest adverse impact on subsequent reproductive health. The reproductive system develops in stages...

Arabidopsis CALCINEURIN B-LIKE10 Functions Independently of the SOS Pathway during Reproductive Development in Saline Conditions1[OPEN

PubMed Central

Smith, Steven E.; Schumaker, Karen S.

2016-01-01

The accumulation of sodium in soil (saline conditions) negatively affects plant growth and development. The Salt Overly Sensitive (SOS) pathway in Arabidopsis (Arabidopsis thaliana) functions to remove sodium from the cytosol during vegetative development preventing its accumulation to toxic levels. In this pathway, the SOS3 and CALCINEURIN B-LIKE10 (CBL10) calcium sensors interact with the SOS2 protein kinase to activate sodium/proton exchange at the plasma membrane (SOS1) or vacuolar membrane. To determine if the same pathway functions during reproductive development in response to salt, fertility was analyzed in wild type and the SOS pathway mutants grown in saline conditions. In response to salt, CBL10 functions early in reproductive development before fertilization, while SOS1 functions mostly after fertilization when seed development begins. Neither SOS2 nor SOS3 function in reproductive development in response to salt. Loss of CBL10 function resulted in reduced anther dehiscence, shortened stamen filaments, and aborted pollen development. In addition, cbl10 mutant pistils could not sustain the growth of wild-type pollen tubes. These results suggest that CBL10 is critical for reproductive development in the presence of salt and that it functions in different pathways during vegetative and reproductive development. PMID:26979332

From esterilología to reproductive biology: The story of the Mexican assisted reproduction business.

PubMed

González-Santos, Sandra P

2016-06-01

This paper provides the first overview of how assisted reproduction emerged and developed in Mexico. In doing so it addresses two broad points: when and how treatments using assisted reproductive technology became common practice within reproductive medicine; and how the Mexican assisted reproduction industry emerged. The paper begins in 1949, when the first medical association dedicated to esterilología - the biomedical area focused on the study of infertility - was established, thus providing the epistemic and professional ground upon which assisted reproductive technology would later thrive. The paper then traces the way in which this biomedical industry developed, from individual doctors in their practices to networks of clinics and from a clinical practice to a reproductive industry. It also describes the different ways in which the professional community and the government have worked towards developing a regulatory frame for the practice of assisted reproduction. The paper is informed by ethnographic work conducted at clinics, conferences, online forums and websites, as well as by analysis of the contemporary national media, government documents and national medical journals from the early mid-twentieth century to the those published today.

Why acquiesce? Worker reproductive parasitism in the Eastern honeybee (Apis cerana).

PubMed

Holmes, M J; Tan, K; Wang, Z; Oldroyd, B P; Beekman, M

2014-05-01

Most societies are vulnerable to rogue individuals that pursue their own interests at the expense of the collective entity. Societies often protect themselves from selfish behaviour by 'policing', thereby enforcing the interests of the collective over those of individuals. In insect societies, for example, selfish workers can activate their ovaries and lay eggs, exploiting the collective brood rearing system for individual benefit. Policing, usually in the form of oophagy of worker-laid eggs, controls selfish behaviour. Importantly, once an effective system of policing has evolved, the incentive for personal reproduction is lost, and 'reproductive acquiescence' in which ovary activation is rare or absent is predicted to evolve. Studies of social Hymenoptera have largely supported the prediction of worker 'acquiescence'; workers of most species where policing is well developed have inactive ovaries. However, the eastern honeybee Apis cerana appears to be an exception. A. cerana colonies are characterized by highly efficient policing, yet about 5% of workers have active ovaries, even when a queen is present. This suggests that the evolution of acquiescence is incomplete in A. cerana. We regularly sampled male eggs and pupae from four A. cerana colonies. Workers had high levels of ovary activation overall (11.7%), and 3.8% of assignable male eggs and 1.1% of assignable male pupae were worker-laid. We conclude that workers with active ovaries lay their eggs, but these rarely survive to pupation because of intense policing. We then used our findings as well as previously published data on A. cerana and A. mellifera to redo the meta-analysis on which reproductive acquiescence theory is based. Including data on both species did not affect the relationship between effectiveness of policing and levels of worker reproduction. Their inclusion did, however, seriously weaken the relationship between relatedness among workers and levels of worker reproduction. Our work thus suggests that relatedness among workers does not affect the probability that workers will attempt to reproduce, but that it is coercion by peers that limits worker reproduction. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

Reproductive science as an essential component of conservation biology.

PubMed

Holt, William V; Brown, Janine L; Comizzoli, Pierre

2014-01-01

In this chapter we argue that reproductive science in its broadest sense has never been more important in terms of its value to conservation biology, which itself is a synthetic and multidisciplinary topic. Over recent years the place of reproductive science in wildlife conservation has developed massively across a wide and integrated range of cutting edge topics. We now have unprecedented insight into the way that environmental change affects basic reproductive functions such as ovulation, sperm production, pregnancy and embryo development through previously unsuspected influences such as epigenetic modulation of the genome. Environmental change in its broadest sense alters the quality of foodstuffs that all animals need for reproductive success, changes the synchrony between breeding seasons and reproductive events, perturbs gonadal and embryo development through the presence of pollutants in the environment and drives species to adapt their behaviour and phenotype. In this book we explore many aspects of reproductive science and present wide ranging and up to date accounts of the scientific and technological advances that are currently enabling reproductive science to support conservation biology.

How maternal investment varies with environmental factors and the age and physiological state of wild tsetse Glossina pallidipes and Glossina morsitans morsitans

PubMed Central

Muzari, M. Odwell; English, Sinead

2018-01-01

Theory suggests females should optimize resource allocation across reproductive bouts to maximize lifetime reproduction, balancing current and future reproductive efforts according to physiological state and projected survival and reproduction. Tests of these ideas focus on long-lived vertebrates: few measure age-related reproductive output in iteroparous invertebrates, or partition reserves between those allocated to offspring versus mothers. We investigated how maternal age, and environmental and physiological factors influence reproductive investment in wild tsetse, Glossina pallidipes Austen and G. morsitans morsitans Westwood. Tsetse provide a tractable system to measure reproductive allocation. Females exhibit high maternal investment, producing single, large offspring that rely exclusively on maternal reserves. We find that mothers in better physiological condition and experiencing cooler temperatures produce larger offspring. Pupal size increases significantly but weakly with age. In both species, females with less fat invest proportionately more in offspring. Post-partum fat decreases in flies with badly frayed wings: poor flight capability may limit their feeding efficiency, or they may sacrifice more reserves as a terminal investment. Our results support evidence that offspring size increases with maternal size, investment depends on the environment, and females with lower chances of future reproduction invest more into current offspring. We discuss the implications of maternal effects for predicting vector population responses to environmental change. PMID:29515882

New observations on gametogenic development and reproductive experimental tools to support seed yield improvement in cowpea [Vigna unguiculata (L.) Walp].

PubMed

Salinas-Gamboa, Rigel; Johnson, Susan D; Sánchez-León, Nidia; Koltunow, Anna M G; Vielle-Calzada, Jean-Philippe

2016-06-01

Cowpea reproductive tools. Vigna unguiculata L. Walp. (cowpea) is recognized as a major legume food crop in Africa, but seed yields remain low in most varieties adapted to local conditions. The development of hybrid cowpea seed that could be saved after each generation, enabling significant yield increases, will require manipulation of reproductive development from a sexual to an asexual mode. To develop new technologies that could support the biotechnological manipulation of reproductive development in cowpea, we examined gametogenesis and seed formation in two transformable, African-adapted, day-length-insensitive varieties. Here, we show that these two varieties exhibit distinct morphological and phenological traits but share a common developmental sequence in terms of ovule formation and gametogenesis. We present a reproductive calendar that allows prediction of male and female gametogenesis on the basis of sporophytic parameters related to floral bud size and reproductive organ development, determining that gametogenesis occurs more rapidly in the anther than in the ovule. We also show that the mode of megagametogenesis is of the Polygonum-type and not Oenothera-type, as previously reported. Finally, we developed a whole-mount immunolocalization protocol and applied it to detect meiotic proteins in the cowpea megaspore mother cell, opening opportunities for comparing the dynamics of protein localization during male and female meiosis, as well as other reproductive events in this emerging legume model system.

Gender-related traits in the dioecious shrub Empetrum rubrum in two plant communities in the Magellanic steppe

NASA Astrophysics Data System (ADS)

Díaz-Barradas, Mari Cruz; Zunzunegui, María; Collantes, Marta; Álvarez-Cansino, Leonor; García Novo, Francisco

2014-10-01

Following the theory on costs of reproduction, sexually dimorphic plants may exhibit several trade-offs in energy and resources that can determine gender dimorphism in morphological or physiological traits, especially during the reproductive period. In this study we assess whether the sexes of the dioecious species Empetrum rubrum differ in morphological and ecophysiological traits related to water economy and photochemical efficiency and whether these differences change in nearby populations with contrasting plant communities. We conducted physiological, morphological, sex ratio, and cover measurements in E. rubrum plants in the Magellanic steppe, North-Eastern part of Tierra del Fuego (Argentina), from two types of heathlands with differing community composition. We found differences between sites in soil pH and wind speed at the canopy level. E. rubrum plants exhibited lower photosynthetic height and higher LAI (leaf area index), lower RWC (relative water content) and higher water-use efficiency (lower Δ13C) in the heathland with harsher environmental conditions. Gender dimorphism in the physiological response was patent for photochemical efficiency and water use (RWC and Δ13C discrimination), with males showing a more conservative strategy in relation to females. Accordingly, male-biased sex ratio in the stress-prone community suggested a better performance of male plants under stressful environmental conditions. The integrated analysis of all variables (photochemical efficiency, RWC, leaf dry matter content (LDMC), pigments, and Δ13C) indicated an interaction between gender and heathland community effects in the physiological response. We suggest that female plants may exhibit compensatory mechanisms to face their higher reproductive costs.

Reproductive health care strategy -- a gender-sensitive approach to family welfare.

PubMed

Anita

1996-01-01

The author advocates a reproductive health care strategy to revitalize India's family welfare program. A major shift in focus is needed in population policy and programs to incorporate a gender-sensitive approach. That shift should help to clear the path toward improved health status for women and female children. Consensus reached at the UN's 1994 International Conference on Population and Development supported a change in population and development policies, affording women's empowerment, gender equality, and equity greater priority for a meaningful policy of human-centered sustainable development. Reproductive health care, reproductive health in practice, the quality of care in reproductive health, gender equality as a human right, and empowering women are discussed.

Environmentally induced responses co-opted for reproductive altruism

PubMed Central

Nedelcu, Aurora M.

2009-01-01

Reproductive altruism is an extreme form of altruism best typified by sterile castes in social insects and somatic cells in multicellular organisms. Although reproductive altruism is central to the evolution of multicellularity and eusociality, the mechanistic basis for the evolution of this behaviour is yet to be deciphered. Here, we report that the gene responsible for the permanent suppression of reproduction in the somatic cells of the multicellular green alga, Volvox carteri, evolved from a gene that in its unicellular relative, Chlamydomonas reinhardtii, is part of the general acclimation response to various environmental stress factors, which includes the temporary suppression of reproduction. Furthermore, we propose a model for the evolution of soma, in which by simulating the acclimation signal (i.e. a change in cellular redox status) in a developmental rather than environmental context, responses beneficial to a unicellular individual can be co-opted into an altruistic behaviour at the group level. The co-option of environmentally induced responses for reproductive altruism can contribute to the stability of this behaviour, as the loss of such responses would be costly for the individual. This hypothesis also predicts that temporally varying environments, which will select for more efficient acclimation responses, are likely to be more conducive to the evolution of reproductive altruism. PMID:19578098

Environmentally induced responses co-opted for reproductive altruism.

PubMed

Nedelcu, Aurora M

2009-12-23

Reproductive altruism is an extreme form of altruism best typified by sterile castes in social insects and somatic cells in multicellular organisms. Although reproductive altruism is central to the evolution of multicellularity and eusociality, the mechanistic basis for the evolution of this behaviour is yet to be deciphered. Here, we report that the gene responsible for the permanent suppression of reproduction in the somatic cells of the multicellular green alga, Volvox carteri, evolved from a gene that in its unicellular relative, Chlamydomonas reinhardtii, is part of the general acclimation response to various environmental stress factors, which includes the temporary suppression of reproduction. Furthermore, we propose a model for the evolution of soma, in which by simulating the acclimation signal (i.e. a change in cellular redox status) in a developmental rather than environmental context, responses beneficial to a unicellular individual can be co-opted into an altruistic behaviour at the group level. The co-option of environmentally induced responses for reproductive altruism can contribute to the stability of this behaviour, as the loss of such responses would be costly for the individual. This hypothesis also predicts that temporally varying environments, which will select for more efficient acclimation responses, are likely to be more conducive to the evolution of reproductive altruism.

Effects of Heat Stress on the Well-Being, Fertility, and Hatchability of Chickens in the Northern Guinea Savannah Zone of Nigeria: A Review

PubMed Central

Ayo, J. O.; Obidi, J. A.; Rekwot, P. I.

2011-01-01

The paper examines heat stress and its adverse effects as a hindrance to profitable poultry production in the tropics, with emphasis on the Northern Guinea Savannah zone of Nigeria. It elucidates the general negative effects of heat stress on physiological parameters of domestic chickens, and the specific impact of the stress on reproduction in the tropics. The deleterious effects are expressed in poor poultry well-being and reproductive performance. It is concluded that measures aimed at alleviating heat stress in domestic chickens must be adopted in order to enhance reproductive and, consequently, efficiency of modern poultry production in the tropics. PMID:23738109

Cancer susceptibility and reproductive trade-offs: a model of the evolution of cancer defences

PubMed Central

Boddy, Amy M.; Kokko, Hanna; Breden, Felix; Wilkinson, Gerald S.; Aktipis, C. Athena

2015-01-01

The factors influencing cancer susceptibility and why it varies across species are major open questions in the field of cancer biology. One underexplored source of variation in cancer susceptibility may arise from trade-offs between reproductive competitiveness (e.g. sexually selected traits, earlier reproduction and higher fertility) and cancer defence. We build a model that contrasts the probabilistic onset of cancer with other, extrinsic causes of mortality and use it to predict that intense reproductive competition will lower cancer defences and increase cancer incidence. We explore the trade-off between cancer defences and intraspecific competition across different extrinsic mortality conditions and different levels of trade-off intensity, and find the largest effect of competition on cancer in species where low extrinsic mortality combines with strong trade-offs. In such species, selection to delay cancer and selection to outcompete conspecifics are both strong, and the latter conflicts with the former. We discuss evidence for the assumed trade-off between reproductive competitiveness and cancer susceptibility. Sexually selected traits such as ornaments or large body size require high levels of cell proliferation and appear to be associated with greater cancer susceptibility. Similar associations exist for female traits such as continuous egg-laying in domestic hens and earlier reproductive maturity. Trade-offs between reproduction and cancer defences may be instantiated by a variety of mechanisms, including higher levels of growth factors and hormones, less efficient cell-cycle control and less DNA repair, or simply a larger number of cell divisions (relevant when reproductive success requires large body size or rapid reproductive cycles). These mechanisms can affect intra- and interspecific variation in cancer susceptibility arising from rapid cell proliferation during reproductive maturation, intrasexual competition and reproduction. PMID:26056364

Specialization on pollen or nectar in bumblebee foragers is not associated with ovary size, lipid reserves or sensory tuning

PubMed Central

Graystock, Peter; Hughes, William O.H.

2016-01-01

Foraging specialization allows social insects to more efficiently exploit resources in their environment. Recent research on honeybees suggests that specialization on pollen or nectar among foragers is linked to reproductive physiology and sensory tuning (the Reproductive Ground-Plan Hypothesis; RGPH). However, our understanding of the underlying physiological relationships in non-Apis bees is still limited. Here we show that the bumblebee Bombus terrestris has specialist pollen and nectar foragers, and test whether foraging specialization in B. terrestris is linked to reproductive physiology, measured as ovarian activation. We show that neither ovary size, sensory sensitivity, measured through proboscis extension response (PER), or whole-body lipid stores differed between pollen foragers, nectar foragers, or generalist foragers. Body size also did not differ between any of these three forager groups. Non-foragers had significantly larger ovaries than foragers. This suggests that potentially reproductive individuals avoid foraging. PMID:27812411

OMICS: Current and future perspectives in reproductive medicine and technology

PubMed Central

Egea, Rocío Rivera; Puchalt, Nicolás Garrido; Escrivá, Marcos Meseguer; Varghese, Alex C.

2014-01-01

Many couples present fertility problems at their reproductive age, and although in the last years, the efficiency of assisted reproduction techniques has increased, these are still far from being 100% effective. A key issue in this field is the proper assessment of germ cells, embryos and endometrium quality, in order to determine the actual likelihood to succeed. Currently available analysis is mainly based on morphological features of oocytes, sperm and embryos and although these strategies have improved the results, there is an urgent need of new diagnostic and therapeutic tools. The emergence of the - OMICS technologies (epigenomics, genomics, transcriptomics, proteomics and metabolomics) permitted the improvement on the knowledge in this field, by providing with a huge amount of information regarding the biological processes involved in reproductive success, thereby getting a broader view of complex biological systems with a relatively low cost and effort. PMID:25191020

Knowledge of and attitudes towards sexual and reproductive health in adults in Shiraz: a need for further education.

PubMed

Khajehei, M; Ziyadlou, S; Ghanizadeh, A

2013-12-01

Sexual health influences general well-being and the overall quality of life of all men and women. This study in Shiraz, Islamic Republic of Iran, aimed to assess the level of knowledge of and attitudes towards sexual and reproductive health among adults. In a cross-sectional study in 2010, 276 men and 281 women were recruited at pre-marital counselling courses and completed a 33-item anonymous questionnaire in private. The overall level of knowledge of men and women was low. Both men and women had low scores on knowledge of genital anatomy, sexually transmitted infections and contraceptive use. The majority of participants had positive attitudes towards implementing educational programmes on sexual and reproductive health issues for young adults and prior to marriage. Efficient educational programmes providing up-to-date information about sexual and reproductive health are needed in the Islamic Republic of Iran.

Sexual and reproductive health and rights in the sustainable development goals and the post-2015 development agenda: less than a year to go.

PubMed

Haslegrave, Marianne

2014-11-01

Since the International Conference on Population and Development (ICPD) in Cairo in 1994 there have been significant achievements in moving towards the goal of sexual and reproductive health and rights. Yet there have also been disappointments, as demonstrated in the Millennium Development Goals, even though in 2007 a target on reproductive health was added. Most recently, the 20-year review of the implementation of the ICPD Programme of Action, ICPD Beyond 2014, has taken place, which has moved forward the sexual and reproductive health and rights agenda. But, the main arena for future negotiations has changed and the UN is in the process of negotiating the post-2015 development agenda and the sustainable development goals (SDGs). This paper assesses what has been taking place since 2013 and provides information as to how the process for the post-2015 development agenda and the SDGs are likely to move forward. An understanding of what has been achieved, the processes as they are now proceeding and their future development are important for moving towards the ultimate goal of achieving sexual and reproductive health and rights in the next 15 years. Copyright © 2014 Reproductive Health Matters. Published by Elsevier Ltd. All rights reserved.

Is there a role for organic trace element supplements in transition cow health?

PubMed

Andrieu, S

2008-04-01

Optimal transition cow health is the key to success of the subsequent lactation, and increasing attention has been focused on management and nutritional practices that support it. Physiological stress during the transition period alters the efficiency of the immune system, making the lactating dairy cow more susceptible to infectious diseases, such as mastitis and metritis, with subsequent impairment of reproductive performance. Trace elements have a specific role in free radical control at the cellular level and influence the anti-oxidant/free radical balance. Dietary trace elements must be available for absorption throughout the whole of the digestive process until they reach the final site of absorption in the small intestine. Negative interactions between minerals can occur and, as the intestinal environment lowers the absorption of ionic minerals, chelation technology has been developed to increase mineral bioavailability. Organic trace elements have been used in dairy cow experiments, resulting in significant improvements in udder health, lameness and reproductive performance.

Maternal antibody, vaccination and reproductive failure in dogs with parvovirus infection.

PubMed

Gooding, G E; Robinson, W F

1982-12-01

The maternal antibody (MAb) titre to canine parvovirus (CPV) was determined on consecutive serums from 39 puppies in 7 litters. Vaccination with inactivated CPV was performed at a variety of ages and the response of the puppies determined. Transfer of MAb was demonstrated in 71% (5/7) of the litters and persisted for up to 10 weeks in some litters. MAb titres of greater than 20 precluded a vaccination response by puppies. Sixty- one per cent (8/13) of puppies responded to vaccination when the MAb titre was less than 20. However, no anamestic response occurred and in some cases a decrease in antibody titre was observed following a second vaccination. During an outbreak of canine parvovirus enteritis (CPE) in the kennel, 33 puppies developed clinical signs of enteritis. Of these puppies 85% (28) had MAb titres of less than 80 at the onset of clinical signs. Fifty per cent (4/8) of the puppies which responded to vaccination developed CPE, whereas 100% (5/5) of those that did not respond to vaccination developed CPE. The results indicate that MAb may persist for up to 10 weeks and puppies with MAb in the titre range greater than 20 to less than 80 do not respond to vaccination but are still susceptible to infection. It is also apparent that a significant minority of puppies with MAb less than 20 do not respond to vaccination. An examination of the breeding records of the kennel for the 7 year period 1973-1981 demonstrated a sudden decrease in reproductive efficiency during and subsequent to 1978. This coincided with the recognition of cases of CPV infection in the kennel. It is suggested that further investigation is required into the possible role of CPV in reproductive failure.

Regulation of stem cell maintenance by the Polycomb protein FIE has been conserved during land plant evolution.

PubMed

Mosquna, Assaf; Katz, Aviva; Decker, Eva L; Rensing, Stefan A; Reski, Ralf; Ohad, Nir

2009-07-01

The Polycomb group (PcG) complex is involved in the epigenetic control of gene expression profiles. In flowering plants, PcG proteins regulate vegetative and reproductive programs. Epigenetically inherited states established in the gametophyte generation are maintained after fertilization in the sporophyte generation, having a profound influence on seed development. The gametophyte size and phase dominance were dramatically reduced during angiosperm evolution, and have specialized in flowering plants to support the reproductive process. The moss Physcomitrella patens is an ideal organism in which to study epigenetic processes during the gametophyte stage, as it possesses a dominant photosynthetic gametophytic haploid phase and efficient homologous recombination, allowing targeted gene replacement. We show that P. patens PcG protein FIE (PpFIE) accumulates in haploid meristematic cells and in cells that undergo fate transition during dedifferentiation programs in the gametophyte. In the absence of PpFIE, meristems overproliferate and are unable to develop leafy gametophytes or reach the reproductive phase. This aberrant phenotype might result from failure of the PcG complex to repress proliferation and differentiation of three-faced apical stem cells, which are designated to become lateral shoots. The PpFIE phenotype can be partially rescued by FIE of Arabidopsis thaliana, a flowering plant that diverged >450 million years ago from bryophytes. PpFIE can partially complement the A. thaliana fie mutant, illustrating functional conservation of the protein during evolution in regulating the differentiation of meristematic cells in gametophyte development, both in bryophytes and angiosperms. This mechanism was harnessed at the onset of the evolution of alternating generations, facilitating the establishment of sporophytic developmental programs.

Human therapeutic cloning (NTSC): applying research from mammalian reproductive cloning.

PubMed

French, Andrew J; Wood, Samuel H; Trounson, Alan O

2006-01-01

Human therapeutic cloning or nuclear transfer stem cells (NTSC) to produce patient-specific stem cells, holds considerable promise in the field of regenerative medicine. The recent withdrawal of the only scientific publications claiming the successful generation of NTSC lines afford an opportunity to review the available research in mammalian reproductive somatic cell nuclear transfer (SCNT) with the goal of progressing human NTSC. The process of SCNT is prone to epigenetic abnormalities that contribute to very low success rates. Although there are high mortality rates in some species of cloned animals, most surviving clones have been shown to have normal phenotypic and physiological characteristics and to produce healthy offspring. This technology has been applied to an increasing number of mammals for utility in research, agriculture, conservation, and biomedicine. In contrast, attempts at SCNT to produce human embryonic stem cells (hESCs) have been disappointing. Only one group has published reliable evidence of success in deriving a cloned human blastocyst, using an undifferentiated hESC donor cell, and it failed to develop into a hESC line. When optimal conditions are present, it appears that in vitro development of cloned and parthenogenetic embryos, both of which may be utilized to produce hESCs, may be similar to in vitro fertilized embryos. The derivation of ESC lines from cloned embryos is substantially more efficient than the production of viable offspring. This review summarizes developments in mammalian reproductive cloning, cell-to-cell fusion alternatives, and strategies for oocyte procurement that may provide important clues facilitating progress in human therapeutic cloning leading to the successful application of cell-based therapies utilizing autologous hESC lines.

ASPECTS OF BASIC REPRODUCTIVE BIOLOGY AND ENDOCRINOLOGY IN THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

EPA Science Inventory

The fathead minnow has been proposed as a model species for assessing the adverse effects of endocrine-disrupting chemicals (EDCs) on reproduction and development. The purpose of these studies was to develop baseline reproductive biology and endocrinology data for this species to...

Histological method for evaluation of the efficiency of Enerlit-Clima.

PubMed

Gol'dshtein, D V; Vikhlyantseva, E V; Sakharova, N K; Maevskii, E I; Pogorelov, A G; Uchitel', M L

2004-08-01

We propose a method of evaluation of anticlimacteric efficiency of a drug by its effect on the estrous cycle. The study was carried out on 9-month-old mice with retained, but notably reduced reproductive function. Analysis of the cell components of the estrous cycle was carried out on histological preparations of vaginal smears.

Wombat reproduction (Marsupialia; Vombatidae): an update and future directions for the development of artificial breeding technology.

PubMed

Hogan, Lindsay A; Janssen, Tina; Johnston, Stephen D

2013-06-01

This review provides an update on what is currently known about wombat reproductive biology and reports on attempts made to manipulate and/or enhance wombat reproduction as part of the development of artificial reproductive technology (ART) in this taxon. Over the last decade, the logistical difficulties associated with monitoring a nocturnal and semi-fossorial species have largely been overcome, enabling new features of wombat physiology and behaviour to be elucidated. Despite this progress, captive propagation rates are still poor and there are areas of wombat reproductive biology that still require attention, e.g. further characterisation of the oestrous cycle and oestrus. Numerous advances in the use of ART have also been recently developed in the Vombatidae but despite this research, practical methods of manipulating wombat reproduction for the purposes of obtaining research material or for artificial breeding are not yet available. Improvement of the propagation, genetic diversity and management of wombat populations requires a thorough understanding of Vombatidae reproduction. While semen collection and cryopreservation in wombats is fairly straightforward there is currently an inability to detect, induce or synchronise oestrus/ovulation and this is an impeding progress in the development of artificial insemination in this taxon.

Development and application of a crossbreeding simulation model for goat production systems in tropical regions.

PubMed

Tsukahara, Y; Oishi, K; Hirooka, H

2011-12-01

A deterministic simulation model was developed to estimate biological production efficiency and to evaluate goat crossbreeding systems under tropical conditions. The model involves 5 production systems: pure indigenous, first filial generations (F1), backcross (BC), composite breeds of F1 (CMP(F1)), and BC (CMP(BC)). The model first simulates growth, reproduction, lactation, and energy intakes of a doe and a kid on a 1-d time step at the individual level and thereafter the outputs are integrated into the herd dynamics program. The ability of the model to simulate individual performances was tested under a base situation. The simulation results represented daily BW changes, ME requirements, and milk yield and the estimates were within the range of published data. Two conventional goat production scenarios (an intensive milk production scenario and an integrated goat and oil palm production scenario) in Malaysia were examined. The simulation results of the intensive milk production scenario showed the greater production efficiency of the CMP(BC) and CMP(F1) systems and decreased production efficiency of the F1 and BC systems. The results of the integrated goat and oil palm production scenario showed that the production efficiency and stocking rate were greater for the indigenous goats than for the crossbreeding systems.

Resource flows for health care: Namibia reproductive health sub-accounts.

PubMed

Mbeeli, Thomas; Samahiya, Muine; Ravishankar, Nirmala; Zere, Eyob; Kirigia, Joses M

2011-12-24

Implementing initiatives to achieve the targets of MDG 5 requires sufficient financial resources that are mobilized and utilized in an equitable, efficient and sustainable manner. Informed decision making to this end requires the availability of reliable health financing information. This is accomplished by means of Reproductive Health (RH) sub-account, which captures and organizes expenditure on RH services in two-dimensional tables from financing sources to end users. The specific objectives of this study are: (i) to quantify total expenditure on reproductive health services; and (ii) to examine the flow of RH funds from sources to end users. The RH sub-account was part of the general National Health Accounts exercise covering the Financial Years 2007/08 and 2008/09. Primary data were collected from employers, medical aid schemes, donors and government ministries using questionnaire. Secondary data were obtained from various documents of the Namibian Government and the health financing database of the World Health Organization. Data were analyzed using a data screen designed in Microsoft Excel. RH expenditure per woman of reproductive age was US$ 148 and US$ 126 in the 2007/08 and 2008/09 financial years respectively. This is by far higher than what is observed in most African countries. RH expenditure constituted more than 10-12% of the total expenditure on health. Out-of-pocket payment for RH was minimal (less than 4% of the RH spending in both years). Government is the key source of RH spending. Moreover, the public sector is the main financing agent with programmatic control of RH funds and also the main provider of services. Most of the RH expenditure is spent on services of curative care (both in- and out-patient). The proportion allocated for preventive and public health services was not more than 5% in the two financial years. Namibia's expenditure on reproductive health is remarkable by the standards of Africa and other middle-income countries. However, an increasing maternal mortality ratio does not bode well with the level of reproductive health expenditure. It is therefore important to critically examine the state of efficiency in the allocation and use of reproductive health expenditures in order to improve health outcomes.

Effect of TiO2 nanoparticles on the reproduction of silkworm.

PubMed

Ni, Min; Li, Fanchi; Wang, Binbin; Xu, Kaizun; Zhang, Hua; Hu, Jingsheng; Tian, Jianghai; Shen, Weide; Li, Bing

2015-03-01

Silkworm (Bombyx mori) is an important economic insect and the model insect of Lepidoptera. Because of its high fecundity and short reproduction cycle, it has been widely used in reproduction and development research. The high concentrations of titanium dioxide nanoparticles (TiO2 NPs) show reproductive toxicity, while low concentrations of TiO2 NPs have been used as feed additive and demonstrated significant biological activities. However, whether the low concentrations of TiO2 NPs affect the reproduction of B. mori has not been reported. In this study, the growth and development of gonad of B. mori fed with a low concentration of TiO2 NPs (5 mg/L) were investigated by assessing egg production and expression of reproduction-related genes. The results showed that the low concentration of TiO2 NPs resulted in faster development of the ovaries and testes and more gamete differentiation and formation, with an average increase of 51 eggs per insect and 0.34 × 10(-4) g per egg after the feeding. The expressions of several reproduction-related genes were upregulated, such as the yolk-development-related genes Ovo-781 and vitellogenin (Vg) were increased by 5.33- and 6.77-folds, respectively. This study shows that TiO2 NPs feeding at low concentration can enhance the reproduction of B. mori, and these results are useful in developing new methods to improve fecundity in B. mori and providing new clues for its broad biological applications.

Assisted reproduction techniques in the horse.

PubMed

Hinrichs, Katrin

2012-01-01

This paper reviews current equine assisted reproduction techniques. Embryo transfer is the most common equine ART, but is still limited by the inability to superovulate mares effectively. Immature oocytes may be recovered by transvaginal ultrasound-guided aspiration of immature follicles, or from ovaries postmortem, and can be effectively matured in vitro. Notably, the in vivo-matured oocyte may be easily recovered from the stimulated preovulatory follicle. Standard IVF is still not repeatable in the horse; however, embryos and foals can be produced by surgical transfer of mature oocytes to the oviducts of inseminated recipient mares or via intracytoplasmic sperm injection (ICSI). Currently, ICSI and in vitro embryo culture are routinely performed by only a few laboratories, but reported blastocyst development rates approach those found after bovine IVF (i.e. 25%-35%). Nuclear transfer can be relatively efficient (up to 26% live foal rate per transferred embryo), but few laboratories are working in this area. Equine blastocysts may be biopsied via micromanipulation, with normal pregnancy rates after biopsy, and accurate genetic analysis. Equine expanded blastocysts may be vitrified after collapsing them via micromanipulation, with normal pregnancy rates after warming and transfer. Many of these recently developed techniques are now in clinical use.

Temporal requirements of insulin/IGF-1 signaling for proteotoxicity protection.

PubMed

Cohen, Ehud; Du, Deguo; Joyce, Derek; Kapernick, Erik A; Volovik, Yuli; Kelly, Jeffery W; Dillin, Andrew

2010-04-01

Toxic protein aggregation (proteotoxicity) is a unifying feature in the development of late-onset human neurodegenerative disorders. Reduction of insulin/IGF-1 signaling (IIS), a prominent lifespan, developmental and reproductive regulatory pathway, protects worms from proteotoxicity associated with the aggregation of the Alzheimer's disease-linked Abeta peptide. We utilized transgenic nematodes that express human Abeta and found that late life IIS reduction efficiently protects from Abeta toxicity without affecting development, reproduction or lifespan. To alleviate proteotoxic stress in the animal, the IIS requires heat shock factor (HSF)-1 to modulate a protein disaggregase, while DAF-16 regulates a presumptive active aggregase, raising the question of how these opposing activities could be co-regulated. One possibility is that HSF-1 and DAF-16 have distinct temporal requirements for protection from proteotoxicity. Using a conditional RNAi approach, we found an early requirement for HSF-1 that is distinct from the adult functions of DAF-16 for protection from proteotoxicity. Our data also indicate that late life IIS reduction can protect from proteotoxicity when it can no longer promote longevity, strengthening the prospect that IIS reduction might be a promising strategy for the treatment of neurodegenerative disorders caused by proteotoxicity.

WORKSHOP TO IDENTIFY CRITICAL WINDOWS OF EXPOSURE FOR CHILDREN'S HEALTH: REPRODUCTIVE HEALTH IN CHILDREN AND ADOLESCENTS WORK GROUP SUMMARY

EPA Science Inventory

This workgroup report addresses the central question: what are the critical windows during development (pre-conception through puberty) when exposure to xenobiotics may have the greatest adverse impact on subsequent reproductive health. The reproductive system develops in stages...

Women, war, and reproductive health in developing countries.

PubMed

Pillai, Vijayan; Wang, Ya-Chien; Maleku, Arati

2017-01-01

Globally, millions of people are affected by war and conflicts every year. However, women have increasingly suffered the greatest harm by war in more different ways than men. We conceptualize a reproductive rights approach toward examining the effects of war on women's reproductive health in developing countries. Given the rising concerns of exclusion to adequately address women's rights, sexual and gender-based violence, and post-conflict accountability, we specifically focus on the limitations of the Minimum Initial Service Package, a UN-sponsored reproductive health service program in conflict zones while offering a broad reproductive rights-based conceptual lens for examining reproductive health care services in war-torn areas. In addition, we discuss the roles social workers may play at both micro and macro levels in war-torn areas to bring about both short term and long term gains in women's reproductive health.

Method of Reproduction of the Luminous Flux of the LED Light Sources by a Spherical Photometer

NASA Astrophysics Data System (ADS)

Huriev, M.; Neyezhmakov, P.

2018-02-01

In connection with transition to energy-efficient temporally stable light-emitting diodes (LEDs) lighting, a problem of ensuring the traceability of results of measurement of characteristics of light sources arises. The problem is related to existing measurement standards of luminous flux based on spherical photometers optimized for the reference incandescent lamps with a relative spectral characteristic different from the spectrum of the LEDs. We propose a method for reproduction of the luminous flux, which solves this problem.

Development and Evaluation of Reproductive and Developmental Toxicity Tests for Assessing the Hazards of Environmental Contaminants

DTIC Science & Technology

1997-08-01

AL/EQ-TR-1997-0050 DEVELOPMENT AND EVALUATION OF REPRODUCTIVE AND DEVELOPMENT TOXICITY TESTS FOR ASSESSING THE HAZARDS OF ENVIRONMENTAL...SUBTITLE Development and Evaluation of Reproductive and Developmental Toxicity Tests for Assessing the Hazards of Environmental Contaminants 6...pd in testing toxicity in surface waters, ground waters and H- ™t™j£J^^^M hazard assessment when used in conjunction in sediments. FETAX can be usea

Genetic Circuits that Govern Bisexual and Unisexual Reproduction in Cryptococcus neoformans

PubMed Central

Feretzaki, Marianna; Heitman, Joseph

2013-01-01

Cryptococcus neoformans is a human fungal pathogen with a defined sexual cycle. Nutrient-limiting conditions and pheromones induce a dimorphic transition from unicellular yeast to multicellular hyphae and the production of infectious spores. Sexual reproduction involves cells of either opposite (bisexual) or one (unisexual) mating type. Bisexual and unisexual reproduction are governed by shared components of the conserved pheromone-sensing Cpk1 MAPK signal transduction cascade and by Mat2, the major transcriptional regulator of the pathway. However, the downstream targets of the pathway are largely unknown, and homology-based approaches have failed to yield downstream transcriptional regulators or other targets. In this study, we applied insertional mutagenesis via Agrobacterium tumefaciens transkingdom DNA delivery to identify mutants with unisexual reproduction defects. In addition to elements known to be involved in sexual development (Crg1, Ste7, Mat2, and Znf2), three key regulators of sexual development were identified by our screen: Znf3, Spo11, and Ubc5. Spo11 and Ubc5 promote sporulation during both bisexual and unisexual reproduction. Genetic and phenotypic analyses provide further evidence implicating both genes in the regulation of meiosis. Phenotypic analysis of sexual development showed that Znf3 is required for hyphal development during unisexual reproduction and also plays a central role during bisexual reproduction. Znf3 promotes cell fusion and pheromone production through a pathway parallel to and independent of the pheromone signaling cascade. Surprisingly, Znf3 participates in transposon silencing during unisexual reproduction and may serve as a link between RNAi silencing and sexual development. Our studies illustrate the power of unbiased genetic screens to reveal both novel and conserved circuits that operate sexual reproduction. PMID:23966871

Genetic circuits that govern bisexual and unisexual reproduction in Cryptococcus neoformans.

PubMed

Feretzaki, Marianna; Heitman, Joseph

2013-01-01

Cryptococcus neoformans is a human fungal pathogen with a defined sexual cycle. Nutrient-limiting conditions and pheromones induce a dimorphic transition from unicellular yeast to multicellular hyphae and the production of infectious spores. Sexual reproduction involves cells of either opposite (bisexual) or one (unisexual) mating type. Bisexual and unisexual reproduction are governed by shared components of the conserved pheromone-sensing Cpk1 MAPK signal transduction cascade and by Mat2, the major transcriptional regulator of the pathway. However, the downstream targets of the pathway are largely unknown, and homology-based approaches have failed to yield downstream transcriptional regulators or other targets. In this study, we applied insertional mutagenesis via Agrobacterium tumefaciens transkingdom DNA delivery to identify mutants with unisexual reproduction defects. In addition to elements known to be involved in sexual development (Crg1, Ste7, Mat2, and Znf2), three key regulators of sexual development were identified by our screen: Znf3, Spo11, and Ubc5. Spo11 and Ubc5 promote sporulation during both bisexual and unisexual reproduction. Genetic and phenotypic analyses provide further evidence implicating both genes in the regulation of meiosis. Phenotypic analysis of sexual development showed that Znf3 is required for hyphal development during unisexual reproduction and also plays a central role during bisexual reproduction. Znf3 promotes cell fusion and pheromone production through a pathway parallel to and independent of the pheromone signaling cascade. Surprisingly, Znf3 participates in transposon silencing during unisexual reproduction and may serve as a link between RNAi silencing and sexual development. Our studies illustrate the power of unbiased genetic screens to reveal both novel and conserved circuits that operate sexual reproduction.

Behavioural and physiological consequences of male reproductive trade-offs in edible dormice ( Glis glis)

NASA Astrophysics Data System (ADS)

Fietz, Joanna; Klose, Stefan M.; Kalko, Elisabeth K. V.

2010-10-01

Testosterone mediates male reproductive trade-offs in vertebrates including mammals. In male edible dormice ( Glis glis), reproductivity linked to high levels of testosterone reduces their ability to express torpor, which may be expected to dramatically increase thermoregulatory costs. Aims of this study were therefore to analyse behavioural and physiological consequences of reproductive activity in male edible dormice under ecologically and evolutionary relevant conditions in the field. As we frequently encountered sleeping groups in the field, we hypothesized that social thermoregulation should be an important measure to reduce energy expenditure especially in sexually active male edible dormice. Our results revealed that the occurrence of sleeping groups was negatively influenced by male body mass but not by reproductive status or ambient temperature. In reproductive as in non-reproductive males, the number of individuals huddling together was negatively influenced by their body mass. Thus in general males with a high body mass were sitting in smaller groups than males with a low body mass. However, in reproductive males group size was further negatively affected by ambient temperature and positively by testes size. Thus breeders formed larger sleeping groups at lower ambient temperatures and males with larger testes were found in larger groups than males with smaller testes. Measurements of oxygen consumption demonstrated that grouping behaviour represents an efficient strategy to reduce energy expenditure in edible dormice as it reduced energy requirements by almost 40%. In summary, results of this field study showcase how sexually active male edible dormice may, through behavioural adjustment, counterbalance high thermoregulatory costs associated with reproductive activity.

Reproductive competition between females in the matrilineal Mosuo of southwestern China

PubMed Central

Ji, Ting; Wu, Jia-Jia; He, Qiao-Qiao; Xu, Jing-Jing; Mace, Ruth; Tao, Yi

2013-01-01

The matrilineal Mosuo of southwestern China live in communal households where brothers and sisters of three generations live together (duolocal residence), and men visit their wives, who reside elsewhere, only at night in ‘visiting’ marriages. Here we show that these communally breeding sisters are in reproductive conflict, in the sense that they share the resources needed to reproduce. We analyse determinants of reproductive success in females and males, and show that co-resident female kin are in competition; the more female kin reside in the household, the more reproductive success is reduced. Male reproductive success, however, is not determined by the kin in his natal household; duolocal males are not in reproductive conflict with their siblings. Competition with female cousins can be worse than that between sisters. We also find that female work on the farm (which is the main communal resource) is not equal. We use a ‘tug-of-war’ model of reproductive skew generated by incomplete control, to model the patterns of effort put into competition between sisters and cousins. The model predicts that more dominant (older) sisters will put less effort into reproductive conflict than will less dominant (younger) sisters; but younger sisters will also have lower reproductive success because they are less efficient at gaining access to the shared resource. Both predictions are consistent with our data. Younger sisters work less in the fields than do older sisters, which may represent a form of conflict or may be because their average relatedness to the household is lower than that of their more fertile older sisters. PMID:24167311

Tissue-Specific Transcriptomics Reveals an Important Role of the Unfolded Protein Response in Maintaining Fertility upon Heat Stress in Arabidopsis

PubMed Central

Zhang, Shuang-Shuang; Yang, Hongxing; Ding, Lan; Song, Ze-Ting; Ma, Hong; Chang, Fang

2017-01-01

High temperatures have a great impact on plant reproductive development and subsequent fruit and seed set, but the underlying molecular mechanisms are not well understood. We used transcriptome profiling to investigate the effect of heat stress on reproductive development of Arabidopsis thaliana plants and observed distinct response patterns in vegetative versus reproductive tissues. Exposure to heat stress affected reproductive developmental programs, including early phases of anther/ovule development and meiosis. Also, genes participating in the unfolded protein response (UPR) were enriched in the reproductive tissue-specific genes that were upregulated by heat. Moreover, we found that the UPR-deficient bzip28 bzip60 double mutant was sensitive to heat stresses and had reduced silique length and fertility. Comparison of heat-responsive wild type versus bzip28 bzip60 plants identified 521 genes that were regulated by bZIP28 and bZIP60 upon heat stress during reproductive stages, most of which were noncanonical UPR genes. Chromatin immunoprecipitation coupled with high-throughput sequencing analyses revealed 133 likely direct targets of bZIP28 in Arabidopsis seedlings subjected to heat stress, including 27 genes that were also upregulated by heat during reproductive development. Our results provide important insights into heat responsiveness in Arabidopsis reproductive tissues and demonstrate the protective roles of the UPR for maintaining fertility upon heat stress. PMID:28442596

Phthalate Esters and Reproductive Toxicity** Presentation requested by State of Mass Use Reductions Committee-TURI

EPA Science Inventory

Phthalate esters and reproductive toxicity the presentation described the uses of phthalates, the toxicity to mammals with a focus on reproductive toxicity and the potency of these chemicals to disrupt mammalian reproductive development in utero

Unique strategies to control reproduction in camels.

PubMed

Skidmore, J A; Morton, K M; Billah, M

2010-01-01

The reproductive efficiency of camels is low under natural pastural conditions and so the use of artifical insemination and embryo transfer are becoming increasingly important to improve their breeding potential. Methods to control their reproductive cycle are therefore essential. This review describes characteristics of the ovarian follicular wave pattern in camels and exogenous hormonal control of ovulation. It also summarizes the difficulties involved with artifical insemination and analyzing the highly gelatinous semen, and reports on the latest methods used to try and reduce the viscosity and liquefy camel semen. In addition an account is given of different hormonal and physical methods used to synchronise follicular waves, and various hormone treatments used to broaden the availability of ovulated, asynchronous and non-ovulated recipients are discussed.

Culture time of vitrified/warmed zygotes before microinjection affects the production efficiency of CRISPR-Cas9-mediated knock-in mice.

PubMed

Nakagawa, Yoshiko; Sakuma, Tetsushi; Nishimichi, Norihisa; Yokosaki, Yasuyuki; Takeo, Toru; Nakagata, Naomi; Yamamoto, Takashi

2017-05-15

Robust reproductive engineering techniques are required for the efficient and rapid production of genetically modified mice. We have reported the efficient production of genome-edited mice using reproductive engineering techniques, such as ultra-superovulation, in vitro fertilization (IVF) and vitrification/warming of zygotes. We usually use vitrified/warmed fertilized oocytes created by IVF for microinjection because of work efficiency and flexible scheduling. Here, we investigated whether the culture time of zygotes before microinjection influences the efficiency of producing knock-in mice. Knock-in mice were generated using clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9) system and single-stranded oligodeoxynucleotide (ssODN) or PITCh (Precise Integration into Target Chromosome) system, a method of integrating a donor vector assisted by microhomology-mediated end-joining. The cryopreserved fertilized oocytes were warmed, cultured for several hours and microinjected at different timings. Microinjection was performed with Cas9 protein, guide RNA(s), and an ssODN or PITCh donor plasmid for the ssODN knock-in and the PITCh knock-in, respectively. Different production efficiencies of knock-in mice were observed by changing the timing of microinjection. Our study provides useful information for the CRISPR-Cas9-based generation of knock-in mice. © 2017. Published by The Company of Biologists Ltd.

The 'Dream Team' for sexual, reproductive, maternal, newborn and adolescent health: an adjusted service target model to estimate the ideal mix of health care professionals to cover population need.

PubMed

Ten Hoope-Bender, Petra; Nove, Andrea; Sochas, Laura; Matthews, Zoë; Homer, Caroline S E; Pozo-Martin, Francisco

2017-07-04

A competent, enabled and efficiently deployed health workforce is crucial to the achievement of the health-related sustainable development goals (SDGs). Methods for workforce planning have tended to focus on 'one size fits all' benchmarks, but because populations vary in terms of their demography (e.g. fertility rates) and epidemiology (e.g. HIV prevalence), the level of need for sexual, reproductive, maternal, newborn and adolescent health (SRMNAH) workers also varies, as does the ideal composition of the workforce. In this paper, we aim to provide proof of concept for a new method of workforce planning which takes into account these variations, and allocates tasks to SRMNAH workers according to their competencies, so countries can assess not only the needed size of the SRMNAH workforce, but also its ideal composition (the 'Dream Team'). An adjusted service target model was developed, to estimate (i) the amount of health worker time needed to deliver essential SRMNAH care, and (ii) how many workers from different cadres would be required to meet this need if tasks were allocated according to competencies. The model was applied to six low- and middle-income countries, which varied in terms of current levels of need for health workers, geographical location and stage of economic development: Azerbaijan, Malawi, Myanmar, Peru, Uzbekistan and Zambia. Countries with high rates of fertility and/or HIV need more SRMNAH workers (e.g. Malawi and Zambia each need 44 per 10,000 women of reproductive age, compared with 20-27 in the other four countries). All six countries need between 1.7 and 1.9 midwives per 175 births, i.e. more than the established 1 per 175 births benchmark. There is a need to move beyond universal benchmarks for SRMNAH workforce planning, by taking into account demography and epidemiology. The number and range of workers needed varies according to context. Allocation of tasks according to health worker competencies represents an efficient way to allocate resources and maximise quality of care, and therefore will be useful for countries working towards SDG targets. Midwives/nurse-midwives who are educated according to established global standards can meet 90% or more of the need, if they are part of a wider team operating within an enabled environment.

Does integration of HIV and sexual and reproductive health services improve technical efficiency in Kenya and Swaziland? An application of a two-stage semi parametric approach incorporating quality measures

PubMed Central

Obure, Carol Dayo; Jacobs, Rowena; Guinness, Lorna; Mayhew, Susannah; Vassall, Anna

2016-01-01

Theoretically, integration of vertically organized services is seen as an important approach to improving the efficiency of health service delivery. However, there is a dearth of evidence on the effect of integration on the technical efficiency of health service delivery. Furthermore, where technical efficiency has been assessed, there have been few attempts to incorporate quality measures within efficiency measurement models particularly in sub-Saharan African settings. This paper investigates the technical efficiency and the determinants of technical efficiency of integrated HIV and sexual and reproductive health (SRH) services using data collected from 40 health facilities in Kenya and Swaziland for 2008/2009 and 2010/2011. Incorporating a measure of quality, we estimate the technical efficiency of health facilities and explore the effect of integration and other environmental factors on technical efficiency using a two-stage semi-parametric double bootstrap approach. The empirical results reveal a high degree of inefficiency in the health facilities studied. The mean bias corrected technical efficiency scores taking quality into consideration varied between 22% and 65% depending on the data envelopment analysis (DEA) model specification. The number of additional HIV services in the maternal and child health unit, public ownership and facility type, have a positive and significant effect on technical efficiency. However, number of additional HIV and STI services provided in the same clinical room, proportion of clinical staff to overall staff, proportion of HIV services provided, and rural location had a negative and significant effect on technical efficiency. The low estimates of technical efficiency and mixed effects of the measures of integration on efficiency challenge the notion that integration of HIV and SRH services may substantially improve the technical efficiency of health facilities. The analysis of quality and efficiency as separate dimensions of performance suggest that efficiency may be achieved without sacrificing quality. PMID:26803655

Does integration of HIV and sexual and reproductive health services improve technical efficiency in Kenya and Swaziland? An application of a two-stage semi parametric approach incorporating quality measures.

PubMed

Obure, Carol Dayo; Jacobs, Rowena; Guinness, Lorna; Mayhew, Susannah; Vassall, Anna

2016-02-01

Theoretically, integration of vertically organized services is seen as an important approach to improving the efficiency of health service delivery. However, there is a dearth of evidence on the effect of integration on the technical efficiency of health service delivery. Furthermore, where technical efficiency has been assessed, there have been few attempts to incorporate quality measures within efficiency measurement models particularly in sub-Saharan African settings. This paper investigates the technical efficiency and the determinants of technical efficiency of integrated HIV and sexual and reproductive health (SRH) services using data collected from 40 health facilities in Kenya and Swaziland for 2008/2009 and 2010/2011. Incorporating a measure of quality, we estimate the technical efficiency of health facilities and explore the effect of integration and other environmental factors on technical efficiency using a two-stage semi-parametric double bootstrap approach. The empirical results reveal a high degree of inefficiency in the health facilities studied. The mean bias corrected technical efficiency scores taking quality into consideration varied between 22% and 65% depending on the data envelopment analysis (DEA) model specification. The number of additional HIV services in the maternal and child health unit, public ownership and facility type, have a positive and significant effect on technical efficiency. However, number of additional HIV and STI services provided in the same clinical room, proportion of clinical staff to overall staff, proportion of HIV services provided, and rural location had a negative and significant effect on technical efficiency. The low estimates of technical efficiency and mixed effects of the measures of integration on efficiency challenge the notion that integration of HIV and SRH services may substantially improve the technical efficiency of health facilities. The analysis of quality and efficiency as separate dimensions of performance suggest that efficiency may be achieved without sacrificing quality. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Interactions of the hormones leptin, ghrelin, adiponectin, resistin, and PYY3-36 with the reproductive system.

PubMed

Budak, Erdal; Fernández Sánchez, Manuel; Bellver, José; Cerveró, Ana; Simón, Carlos; Pellicer, Antonio

2006-06-01

To summarize the effects of novel hormones (leptin, ghrelin, adiponectin, resistin, and PYY3-36) secreted from adipose tissue and the gastrointestinal tract that have been discovered to exert different effects on several reproductive functions, such as the hypothalamic-pituitary-gonadal axis, embryo development, implantation physiology, and clinically relevant conditions. A MEDLINE computer search was performed to identify relevant articles. Leptin and ghrelin exert important roles on body weight regulation, eating behavior, and reproduction, acting on the central nervous system and target reproductive organs. As a marker of adequate nutritional stores, these hormones may act on the central nervous system to initiate the complex process of puberty and maintain normal reproductive function. In addition, leptin and ghrelin and their receptors are involved in reproductive events such as gonadal function, embryo development, and embryo-endometrial interaction. Leptin and ghrelin and other adipose tissue-secreted hormones have significant effects on reproduction. Acting through the brain, these hormones may serve as links between adipose tissue and the reproductive system to supply and regulate energy needs for normal reproduction and pregnancy. Future studies are needed to further clarify the role of these hormones in reproductive events and other related gynecological conditions.

Identification of sites of STAT3 action in the female reproductive tract through conditional gene deletion.

PubMed

Robker, Rebecca L; Watson, Laura N; Robertson, Sarah A; Dunning, Kylie R; McLaughlin, Eileen A; Russell, Darryl L

2014-01-01

The STAT3 transcription factor is a pleiotropic transducer of signalling by hormones, growth factors and cytokines that has been identified in the female reproductive tract from oocytes and granulosa cells of the ovary to uterine epithelial and stromal cells. In the present study we used transgenic models to investigate the importance of STAT3 for reproductive performance in these different tissues. The Cre-LoxP system was used to delete STAT3 in oocytes by crossing Stat3fl/fl with Zp3-cre+ mice, or in ovarian granulosa cells and uterine stroma by crossing with Amhr2-Cre+ mice. Surprisingly, deletion of STAT3 in oocytes had no effect on fertility indicating that the abundance of STAT3 protein in maturing oocytes and fertilized zygotes is not essential to these developmental stages. In Stat3fl/fl;Amhr2-cre+ females impaired fertility was observed through significantly fewer litters and smaller litter size. Ovulation rate, oocyte fertilization and development to blastocyst were unaffected in this line; however, poor recombination efficiency in granulosa cells had yielded no net change in STAT3 protein abundance. In contrast, uteri from these mice showed STAT3 protein depletion selectively from the stomal compartment. A significant reduction in number of viable fetuses on gestational day 18, increased fetal resorptions and disrupted placental morphology were evident causes of the reduced fertility. In conclusion, this study defines an important role for STAT3 in uterine stromal cells during embryo implantation and the development of a functional placenta.

Modeling malaria and typhoid fever co-infection dynamics.

PubMed

Mutua, Jones M; Wang, Feng-Bin; Vaidya, Naveen K

2015-06-01

Malaria and typhoid are among the most endemic diseases, and thus, of major public health concerns in tropical developing countries. In addition to true co-infection of malaria and typhoid, false diagnoses due to similar signs and symptoms and false positive results in testing methods, leading to improper controls, are the major challenges on managing these diseases. In this study, we develop novel mathematical models describing the co-infection dynamics of malaria and typhoid. Through mathematical analyses of our models, we identify distinct features of typhoid and malaria infection dynamics as well as relationships associated to their co-infection. The global dynamics of typhoid can be determined by a single threshold (the typhoid basic reproduction number, R0(T)) while two thresholds (the malaria basic reproduction number, R0(M), and the extinction index, R0(MM)) are needed to determine the global dynamics of malaria. We demonstrate that by using efficient simultaneous prevention programs, the co-infection basic reproduction number, R0, can be brought down to below one, thereby eradicating the diseases. Using our model, we present illustrative numerical results with a case study in the Eastern Province of Kenya to quantify the possible false diagnosis resulting from this co-infection. In Kenya, despite having higher prevalence of typhoid, malaria is more problematic in terms of new infections and disease deaths. We find that false diagnosis-with higher possible cases for typhoid than malaria-cause significant devastating impacts on Kenyan societies. Our results demonstrate that both diseases need to be simultaneously managed for successful control of co-epidemics. Copyright © 2015 Elsevier Inc. All rights reserved.

Application of video recording technology to improve husbandry and reproduction in the carmine bee-eater (Merops n. nubicus).

PubMed

Ferrie, Gina M; Sky, Christy; Schutz, Paul J; Quinones, Glorieli; Breeding, Shawnlei; Plasse, Chelle; Leighty, Katherine A; Bettinger, Tammie L

2016-01-01

Incorporating technology with research is becoming increasingly important to enhance animal welfare in zoological settings. Video technology is used in the management of avian populations to facilitate efficient information collection on aspects of avian reproduction that are impractical or impossible to obtain through direct observation. Disney's Animal Kingdom(®) maintains a successful breeding colony of Northern carmine bee-eaters. This African species is a cavity nester, making their nesting behavior difficult to study and manage in an ex situ setting. After initial research focused on developing a suitable nesting environment, our goal was to continue developing methods to improve reproductive success and increase likelihood of chicks fledging. We installed infrared bullet cameras in five nest boxes and connected them to a digital video recording system, with data recorded continuously through the breeding season. We then scored and summarized nesting behaviors. Using remote video methods of observation provided much insight into the behavior of the birds in the colony's nest boxes. We observed aggression between birds during the egg-laying period, and therefore immediately removed all of the eggs for artificial incubation which completely eliminated egg breakage. We also used observations of adult feeding behavior to refine chick hand-rearing diet and practices. Although many video recording configurations have been summarized and evaluated in various reviews, we found success with the digital video recorder and infrared cameras described here. Applying emerging technologies to cavity nesting avian species is a necessary addition to improving management in and sustainability of zoo avian populations. © 2015 Wiley Periodicals, Inc.

Embryogenic plant cells in microgravity

NASA Technical Reports Server (NTRS)

Krikorian, Abraham D.

1991-01-01

In view of circumstantial evidence for the role of gravity (g) in shaping the embryo environment, normal embryo development may not occur reliably and efficiently in the microgravity environment of space. Attention must accordingly be given to those aspects of higher plant reproductive biology in space environments required for the production of viable embryos in a 'seed to seed to seed' experiment. It is suggested that cultured cells can be grown to be morphogenetically competent, and can be evaluated as to their ability to simulate embryogenic events usually associated with fertilized eggs in the embryo sac of the ovule in the ovary.

Plant reproduction in spaceflight environments

NASA Technical Reports Server (NTRS)

Musgrave, M. E.; Kuang, A.; Porterfield, D. M.

1997-01-01

Because plant reproduction is a complex developmental process there are many possible sites of perturbation by the unusual environments of orbital spacecraft. Previous long-duration experiments on Soviet platforms shared features of slowed development through the vegetative stage of plant growth and aborted reproductive function. Our goal has been to understand how special features of the spaceflight environment impact physiological function and reproductive development. In a series of short-duration experiments in the Shuttle mid-deck we studied early reproductive development in Arabidopsis thaliana. Pollen and ovule development aborted at an early stage in the first experiment on STS-54 which utilized closed plant growth chambers. Post-flight analysis suggested that the plants may have been carbon dioxide limited. Subsequent experiments utilized carbon dioxide enrichment (on STS-51) and cabin air flow-through with an air exchange system (on STS-68). Both modifications allowed pollen and ovule development to occur normally on orbit, and full reproductive development up to the stage of an immature seed occurred on STS-68. However, analysis of plant roots from these experiments demonstrated a limitation in rootzone aeration in the spaceflight material that was not mitigated by these procedures. In the future, additional resources (crew time, upgraded flight hardware, and special platforms) will invite more elaborate, long-duration experimentation. On the ISS, a variable speed centrifuge and upgraded plant habitats will permit detailed experiments on the role of gravity in shaping the plant micro-environment, and what influence this plays during reproduction.

Guiding bioprocess design by microbial ecology.

PubMed

Volmer, Jan; Schmid, Andreas; Bühler, Bruno

2015-06-01

Industrial bioprocess development is driven by profitability and eco-efficiency. It profits from an early stage definition of process and biocatalyst design objectives. Microbial bioprocess environments can be considered as synthetic technical microbial ecosystems. Natural systems follow Darwinian evolution principles aiming at survival and reproduction. Technical systems objectives are eco-efficiency, productivity, and profitable production. Deciphering technical microbial ecology reveals differences and similarities of natural and technical systems objectives, which are discussed in this review in view of biocatalyst and process design and engineering strategies. Strategies for handling opposing objectives of natural and technical systems and for exploiting and engineering natural properties of microorganisms for technical systems are reviewed based on examples. This illustrates the relevance of considering microbial ecology for bioprocess design and the potential for exploitation by synthetic biology strategies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Investigation of a functional role for Titin in the bovine ovary based on the results of an initial whole genome scan for antral follicle count

USDA-ARS?s Scientific Manuscript database

A world-wide food shortage is predicted by the year 2050, and biotechnologies are needed to improve production efficiency in agriculture. Biotechnologies that improve reproductive efficiency in domestic farm species will improve the availability and price of food for the growing world population. ...

[Prevention and protection of workers' reproductive health].

PubMed

Sivochalova, O V; Fesenko, M A; Golovaneva, G V; Morozova, T V; Fedorova, E V; Irmiakova, A R; Gromova, E Iu; Stepanian, I V; Vuĭtsik, P A

2013-01-01

The article mentiones issues of preserving and strengthening the reproductive health of women workers, dealed by researchers of the laboratory, established in 1974. It describes the developed concept of the reproductive health problems and scientific research areas, developed documents, including legislative fields, formulates main prospects of the laboratory to meet the requirements of the present moment. Noted the role of the Problem Commission "Scientific basis for the reproductive health of workers", in the work of the Scientific Council on medical and environmental issues of workers' health.

Advanced seasonal reproductive development in a male urban bird is reflected in earlier plasma luteinizing hormone rise but not energetic status.

PubMed

Davies, Scott; Behbahaninia, Hirbod; Giraudeau, Mathieu; Meddle, Simone L; Waites, Kyle; Deviche, Pierre

2015-12-01

Urban animals inhabit an environment considerably different than do their non-urban conspecifics, and to persist urban animals must adjust to these novel environments. The timing of seasonal reproductive development (i.e., growth of gonads and secondary sex organs) is a fundamental determinant of the breeding period and is frequently advanced in urban bird populations. However, the underlying mechanism(s) by which birds adjust the timing of reproductive development to urban areas remain(s) largely unknown. Here, we compared the timing of vernal reproductive development in free-ranging urban and non-urban male Abert's Towhees, Melozone aberti, in Phoenix, Arizona, USA, and tested the non-mutually exclusive hypotheses that earlier reproductive development is due to improved energetic status and/or earlier increase in endocrine activity of the reproductive system. We found that urban birds initiated testicular development earlier than non-urban birds, but this disparity was not associated with differences in body condition, fat stores, or innate immune performance. These results provide no support for the hypothesis that energetic constraints are responsible for delayed reproductive development of non-urban relative to urban male Abert's Towhees. Urban birds did, however, increase their plasma luteinizing hormone, but not plasma testosterone, earlier than non-urban birds. These findings suggest that adjustment to urban areas by Abert's Towhees involves increases in the endocrine activity of the anterior pituitary gland and/or hypothalamus earlier than non-urban towhees. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Oocyte cryopreservation for donor egg banking.

PubMed

Cobo, Ana; Remohí, José; Chang, Ching-Chien; Nagy, Zsolt Peter

2011-09-01

Oocyte donation is an efficient alternative to using own oocytes in IVF treatment for different indications. Unfortunately, 'traditional' (fresh) egg donations are challenged with inefficiency, difficulties of synchronization, very long waiting periods and lack of quarantine measures. Given the recent improvements in the efficiency of oocyte cryopreservation, it is reasonable to examine if egg donation through oocyte cryopreservation has merits. The objective of the current manuscript is to review existing literature on this topic and to report on the most recent outcomes from two established donor cryobank centres. Reports on egg donation using slow freezing are scarce and though results are encouraging, outcomes are not yet comparable to a fresh egg donation treatment. Vitrification on the other hand appears to provide high survival rates (90%) of donor oocytes and comparable fertilization, embryo development, implantation and pregnancy rates to traditional (fresh) egg donation. Besides the excellent outcomes, the ease of use for both donors and recipients, higher efficiency, lower cost and avoiding the problem of synchronization are all features associated with the benefit of a donor egg cryobank and makes it likely that this approach becomes the future standard of care. Oocyte donation is one of the last resorts in IVF treatment for couples challenged with infertility problems. However, traditional (fresh) egg donation, as it is performed today, is not very efficient, as typically all eggs from one donor are given to only one recipient, it is arduous as it requires an excellent synchronization between the donor and recipient and there are months or years of waiting time. Because of the development of an efficient oocyte cryopreservation technique, it is now possible to cryo-store donor (as well as non-donor) eggs, maintaining their viability and allowing their use whenever there is demand. Therefore, creating a donor oocyte cryobank would carry many advantages. In the present manuscript, the current experience with oocyte donation using cryopreservation technology is reviewed. The outcomes of two recently established donor egg cryobanks at Instituto Valenciano de Infertilidad in Spain and Reproductive Biology Associates in the USA (involving a large number of cases) demonstrate that egg cryo-survival is high and that fertilization, embryo development, implantation and pregnancy rates are similar to those reported after fresh egg donation. It also provides additional advantages of being more efficient, more economical, easier for both donors and recipients and potentially also safer, because eggs can now be quarantined for 6 months (or longer) to retest for infectious diseases in the donors. It is the opinion of the authors, based on several advantages associated with the use of donor egg cryobanking, that in the future there will be fewer traditional egg donations and increasingly more cryo-egg donations. Copyright © 2011 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Endometrial gene expression profile of pregnant sows with extreme phenotypes for reproductive efficiency.

PubMed

Córdoba, S; Balcells, I; Castelló, A; Ovilo, C; Noguera, J L; Timoneda, O; Sánchez, A

2015-10-05

Prolificacy can directly impact porcine profitability, but large genetic variation and low heritability have been found regarding litter size among porcine breeds. To identify key differences in gene expression associated to swine reproductive efficiency, we performed a transcriptome analysis of sows' endometrium from an Iberian x Meishan F2 population at day 30-32 of gestation, classified according to their estimated breeding value (EBV) as high (H, EBV > 0) and low (L, EBV < 0) prolificacy phenotypes. For each sample, mRNA and small RNA libraries were RNA-sequenced, identifying 141 genes and 10 miRNAs differentially expressed between H and L groups. We selected four miRNAs based on their role in reproduction, and five genes displaying the highest differences and a positive mapping into known reproductive QTLs for RT-qPCR validation on the whole extreme population. Significant differences were validated for genes: PTGS2 (p = 0.03; H/L ratio = 3.50), PTHLH (p = 0.03; H/L ratio = 3.69), MMP8 (p = 0.01; H/L ratio =4.41) and SCNN1G (p = 0.04; H/L ratio = 3.42). Although selected miRNAs showed similar expression levels between H and L groups, significant correlation was found between the expression level of ssc-miR-133a (p < 0.01) and ssc-miR-92a (p < 0.01) and validated genes. These results provide a better understanding of the genetic architecture of prolificacy-related traits and embryo implantation failure in pigs.

Manager's handbook for oaks in the north-central states.

Treesearch

Ivan L. Sander

1977-01-01

Presents a key for choosing management options. Discusses silvicultural treatments to ensure reproduction and regulate stand density for efficient timber production. Also discusses water, wildlife, esthetics, and their effects on timber production.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eskenazi, B.; Kimmel, G.

This summary report focuses on current studies on reproductive effects reported at the workshop on Perinatal Exposure to Dioxin-like Compounds and supporting data noted in the discussion. Recent laboratory studies have suggested that altered development (e.g., low birth weight, spontaneous abortion, congenital malformation) and reproductive health (e.g., fertility, sex organ development, reproductive behavior) may be among the most sensitive end points when examining the effects of dioxin-like compounds. Thus, future research should target the reproductive health of both males and females exposed postnatally and prenatally. Studies in humans are needed and are on-going. In animal models, postnatal exposure to dioxinmore » or dioxinlike compounds has been associated with abnormal spermatogenesis and abnormal testicular morphology and size in males and with reduced fertility and endometriosis in females. In utero exposure may also produce profound reproductive consequences in both males and females including delays in sexual maturation, abnormalities in development of sexual organs, and abnormal sexual behavior. The mechanism by which dioxin-like compounds cause reproductive effects is not well delineated. 13 refs.« less

Gender issues in reproductive health: a review.

PubMed

Adinma, Echendu D; Adinma, Brian-D J I

2011-01-01

Gender, for its impact on virtually every contemporary life issue, can rightly be regarded as a foremost component of reproductive health. Reproductive health basically emphasises on people and their rights to sexuality, reproduction, and family planning, and the information to actualize these right, which has been inextricably linked to development at the International Conference on Population and Development (ICPD) held in Cairo, Egypt, in 1994. Women's sexual and reproductive rights became recognised as universal human right, violations of which occur in some reproductive health areas including gender concerns. Gender inequality and inequity encompass gender based violence as well as gender discrimination which cuts across the life cycle of the woman; attitudes, religious and cultural practices of various nations; and issues related to employment, economy, politics, and development. The redress of gender inequality is a collective responsibility of nations and supranational agencies. Nations should adopt a framework hinged on three pedestals--legal, institutional and policy, employing the three recommended approaches of equal treatment, positive action, and gender mainstreaming.

Timing of shoot development transitions affects degree of perenniality in Arabidopsis lyrata (Brassicaceae).

PubMed

Remington, David L; Figueroa, Jennifer; Rane, Mitali

2015-09-17

Perenniality is best understood in quantitative terms, involving the relationship between production vs. turnover of meristems, biomass, or energy reserves. Previous quantitative trait locus (QTL) studies using divergent populations of the perennial rock cress Arabidopsis lyrata have shown that trade-offs in vegetative growth vs. reproduction are due to cascading effects of differences in early vegetative development, which contribute to local adaptation. However, details of the developmental differences and how they affect perenniality remained unclear. In this study, we investigated in detail the developmental differences in perenniality between populations. A. lyrata from Norway and North Carolina populations, representing contrasting environments and degrees of perenniality, were grown under controlled conditions, and data were collected on plant phenology and shoot-level development. We tested hypotheses that differences in perenniality involve strict allocation of lateral meristems to vegetative vs. reproductive fates, or alternatively quantitative effects of pre-reproductive vegetative development. The two populations showed large differences in the degree of vegetative development on individual shoots prior to reproductive transitions. The number of leaves produced on shoots prior to bolting, and not strict meristem allocation or variation in apical dominance, was able to explain variation in the number of inflorescences on individual plants. These results suggested that allocation of time to shoot vegetative vs. reproductive development could be a major factor in resource allocation differences between the populations. Based on these results and those of previous QTL studies, we propose a model in which the degree of shoot vegetative development shapes the developmental context for reproduction and subsequent vegetative growth in different environments. Climate-specific effects of shoot development patterns on reproductive output and survival may result in divergent evolutionary trajectories along a perenniality continuum, which may have broader relevance for plant life history evolution.

Alterations in flowering strategies and sexual allocation of Caragana stenophylla along a climatic aridity gradient.

PubMed

Xie, Lina; Guo, Hongyu; Ma, Chengcang

2016-09-15

Plant can alter reproductive strategies for adaptation to different environments. However, alterations in flowering strategies and sexual allocation for the same species growing in different environments still remain unclear. We examined the sexual reproduction parameters of Caragana stenophylla across four climatic zones from semi-arid, arid, very arid, to intensively arid zones in the Inner Mongolia Steppe, China. Under the relatively favorable climatic conditions of semi-arid zone, C. stenophylla took a K-strategy for flowering (fewer but bigger flowers, and higher seed set). In contrast, under the harsher climatic conditions of intensively arid zone, C. stenophylla took an r-strategy for flowering (more but smaller flowers, and lower seed set). In arid and very arid zones, C. stenophylla exhibited intermediate flowering strategies between K- and r-strategies. In semi-arid, arid and very arid zones, sexual allocation and sexual allocation efficiency (SAE) of C. stenophylla were high, and the population recruitment might be mainly through sexual reproduction; in intensively arid zone, however, sexual allocation and SAE were very low, seed production was very limited, and clonal reproduction might compensate for the decrease in sexual reproduction. Our results suggested that C. stenophylla adapted to the climatic aridity gradient by alterations in flowering strategies and reproductive allocation.

FACTORS AFFECTING REPRODUCTION AND THE IMPORTANCE OF ADULT SIZE ON REPRODUCTIVE OUTPUT OF THE MIDGE, CHIRONOMUS TENTANS

EPA Science Inventory

Incorporating reproductive endpoints into sediment toxicity tests has become an important consideration in ecological risk assessments. The capacity to assess reproduction was one of the primary objectives underlying the recent development of a life-cycle test with the midge, Ch...

Toxic plants: Effects on reproduction and fetal and embryonic development in livestock

USDA-ARS?s Scientific Manuscript database

Reproductive success is dependent on a large number of carefully orchestrated biological events that must occur in a specifically timed sequence. The interference with one of more of these sequences or events may result in total reproductive failure or a more subtle reduction in reproductive potent...

Production and reproduction of Fleckvieh, Brown Swiss, and 2 strains of Holstein-Friesian cows in a pasture-based, seasonal-calving dairy system.

PubMed

Piccand, V; Cutullic, E; Meier, S; Schori, F; Kunz, P L; Roche, J R; Thomet, P

2013-08-01

The first objective of this study was to compare the productive and reproductive performance of Holstein-Friesian (CH HF), Fleckvieh (CH FV), and Brown Swiss (CH BS) cows of Swiss origin with New Zealand Holstein-Friesian (NZ HF) cows in pasture-based compact-calving systems; NZ HF cows were chosen as the reference population for such grazing systems. The second objective was to analyze the relationships within and between breeds regarding reproductive performance, milk yield, and body condition score (BCS) dynamics. On 15 commercial Swiss farms, NZ HF cows were paired with Swiss cows over 3 yr. Overall, the study involved 259 complete lactations from 134 cows: 131 from 58 NZ HF, 40 from 24 CH HF, 43 from 27 CH FV, and 45 from 25 CH BS cows. All production parameters were affected by cow breed. Milk and energy-corrected milk yield over 270 d of lactation differed by 1,000 kg between the 2 extreme groups; CH HF having the highest yield and CH BS the lowest. The NZ HF cows had the greatest milk fat and protein concentrations over the lactation and exhibited the highest lactation persistency. Body weight differed by 90 kg between extreme groups; NZ HF and CH BS being the lightest and CH HF and CH FV the heaviest. As a result, the 2 HF strains achieved the highest milk production efficiency (270-d energy-corrected milk/body weight(0.75)). Although less efficient at milk production, CH FV had a high 21-d submission rate (86%) and a high conception rate within 2 inseminations (89%), achieving high pregnancy rates within the first 3 and 6 wk of the breeding period (65 and 81%, respectively). Conversely, poorer reproductive performance was recorded for CH HF cows, with NZ HF and CH BS being intermediate. Both BCS at nadir and at 100 d postpartum had a positive effect on the 6-wk pregnancy rate, even when breed was included in the model. The BCS at 100 d of lactation also positively affected first service conception rate. In conclusion, despite their high milk production efficiency, even in low-input systems, CH HF were not suited to pasture-based seasonal-calving production systems due to poor reproductive performance. On the contrary, CH FV fulfilled the compact-calving reproduction objectives and deserve further consideration in seasonal calving systems, despite their lower milk production potential. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Longitudinal changes in reproductive hormones and menstrual cyclicity in cynomolgus monkeys during strenuous exercise training: abrupt transition to exercise-induced amenorrhea.

PubMed

Williams, N I; Caston-Balderrama, A L; Helmreich, D L; Parfitt, D B; Nosbisch, C; Cameron, J L

2001-06-01

Cross-sectional studies of exercise-induced reproductive dysfunction have documented a high proportion of menstrual cycle disturbances in women involved in strenuous exercise training. However, longitudinal studies have been needed to examine individual susceptibility to exercise-induced reproductive dysfunction and to elucidate the progression of changes in reproductive function that occur with strenuous exercise training. Using the female cynomolgus monkey (Macaca fascicularis), we documented changes in menstrual cyclicity and patterns of LH, FSH, estradiol, and progesterone secretion as the animals developed exercise-induced amenorrhea. As monkeys gradually increased running to 12.3 +/- 0.9 km/day, body weight did not change significantly although food intake remained constant. The time spent training until amenorrhea developed varied widely among animals (7-24 months; mean = 14.3 +/- 2.2 months) and was not correlated with initial body weight, training distance, or food intake. Consistent changes in function of the reproductive axis occurred abruptly, one to two menstrual cycles before the development of amenorrhea. These included significant declines in plasma reproductive hormone concentrations, an increase in follicular phase length, and a decrease in luteal phase progesterone secretion. These data document a high level of interindividual variability in the development of exercise-induced reproductive dysfunction, delineate the progression of changes in reproductive hormone secretion that occur with exercise training, and illustrate an abrupt transition from normal cyclicity to an amenorrheic state in exercising individuals, that is not necessarily associated with weight loss.

Reproduction trends and the emergence of moral panic.

PubMed

Hanmer, J

1987-01-01

Are we witnessing a moral panic or a moral evaluation in the responses to the new reproductive technologies? Locating women in reproductive technology is a particularly powerful way into a discussion of values and consequences, intended or unintended. Twelve areas are isolated for discussion beginning with issues of definition and location: What is reproductive and genetic engineering? and How does human reproduction fit into bio-technological developments generally? Next issues are raised about how the new developments are being shaped ideologically and how they are being promoted by the state. A series of legal issues affecting women, men, children, embryos and fetuses follow. The focus then shifts to the way women are ideologically constructed: Why is there an assumption that woman = mother, and mother = heterosexual married or stable cohabiting woman?--and socially controlled: Why assume technological change in human reproductive processes means the basic subordination of women to men will not alter? The usefulness of the new technologies in relieving involuntary childlessness is then queried which leads on to a questioning of whether these developments are qualitatively different from other technologies used in human reproduction. Futuristic concerns such as the importance of the male pregnancy and the social consequences of fully medicalising human reproduction are raised. The last area to be considered is protest by women and suggested alternative approaches to increase the social visibility and recognition of the needs and interest of women in the current and potential use of the new medical and scientific developments.

Tissue-Specific Transcriptomics Reveals an Important Role of the Unfolded Protein Response in Maintaining Fertility upon Heat Stress in Arabidopsis.

PubMed

Zhang, Shuang-Shuang; Yang, Hongxing; Ding, Lan; Song, Ze-Ting; Ma, Hong; Chang, Fang; Liu, Jian-Xiang

2017-05-01

High temperatures have a great impact on plant reproductive development and subsequent fruit and seed set, but the underlying molecular mechanisms are not well understood. We used transcriptome profiling to investigate the effect of heat stress on reproductive development of Arabidopsis thaliana plants and observed distinct response patterns in vegetative versus reproductive tissues. Exposure to heat stress affected reproductive developmental programs, including early phases of anther/ovule development and meiosis. Also, genes participating in the unfolded protein response (UPR) were enriched in the reproductive tissue-specific genes that were upregulated by heat. Moreover, we found that the UPR-deficient bzip28 bzip60 double mutant was sensitive to heat stresses and had reduced silique length and fertility. Comparison of heat-responsive wild type versus bzip28 bzip60 plants identified 521 genes that were regulated by bZIP28 and bZIP60 upon heat stress during reproductive stages, most of which were noncanonical UPR genes. Chromatin immunoprecipitation coupled with high-throughput sequencing analyses revealed 133 likely direct targets of bZIP28 in Arabidopsis seedlings subjected to heat stress, including 27 genes that were also upregulated by heat during reproductive development. Our results provide important insights into heat responsiveness in Arabidopsis reproductive tissues and demonstrate the protective roles of the UPR for maintaining fertility upon heat stress. © 2017 American Society of Plant Biologists. All rights reserved.

Lake trout restoration in the Great Lakes: stock-size criteria for natural reproduction

USGS Publications Warehouse

Selgeby, James H.; Bronte, Charles R.; Brown, Edward H.; Hansen, Michael J.; Holey, Mark E.; VanAmberg, Jan P.; Muth, Kenneth M.; Makauskas, Daniel B.; Mckee, Patrick; Anderson, David M.; Ferreri, C. Paola; Schram, Stephen T.

1995-01-01

We examined the question of whether the lake trout restoration program in the Great Lakes has developed brood stocks of adequate size to sustain natural reproduction. Stock size criteria were developed from areas of the Great Lakes where natural reproduction has been successful (defined as detection of age-1 or older recruits by assessment fishing). We contrasted them with stocks in areas with no natural reproduction. Based on the relative abundance of spawners measured in the fall and the presence or absence of natural reproduction in 24 areas of the Great Lakes, we found three distinct sets of lake trout populations. In seven areas of successful natural reproduction, the catch-per-unit-effort (CPE) of spawners ranged from 17 to 135 fish/305 m of gillnet. Stock sizes in these areas were used as a gauge against which stocks in other areas were contrasted. We conclude that stock densities of 17-135 fish/305 m of gill net are adequate for natural reproduction, provided that all other requirements are met. No natural reproduction has been detected in seven other areas, where CPEs of spawners ranged from only 3 to 5 fish/305 m. We conclude that spawning stocks of only 3-5 fish/305 m of net are inadequate to develop measurable natural reproduction. Natural reproduction has also not been detected in ten areas where CPEs of spawners ranged from 43 to 195 fish/305 m of net. We conclude that spawning stocks in these ten areas were adequate to sustain natural reproduction, but that some factor other than parental stock size prevented recruitment of wild lake trout.

Impact of selection for residual feed intake on breeding soundness and reproductive performance of bulls on pasture-based multisire mating.

PubMed

Wang, Z; Colazo, M G; Basarab, J A; Goonewardene, L A; Ambrose, D J; Marques, E; Plastow, G; Miller, S P; Moore, S S

2012-09-01

There is concern in the beef industry that selecting bulls for feed efficiency based on residual feed intake (RFI) may have a negative impact on bull reproductive performance and fertility. Here we investigated the impact of selection of bulls for low RFI on breeding soundness evaluation (BSE), reproductive performance, and fertility of bulls under natural service in multisire mating groups on pasture. Of the 412 RFI-tested bulls available, 98 (23.8%) were culled for performance, type, temperament, or other reasons, and 88 (21.4%) were culled for failing BSE, for an overall cull rate of 45.1%. From among the 314 bulls subjected to BSE, 32 (10.2%), 20 (6.4%), and 36 (11.4%) were culled for poor feet and legs, scrotal circumference, and semen quality, respectively. The BSE traits were not different (P > 0.10) between bulls categorized as either inefficient (+RFI) or efficient (-RFI), but the proportion of bulls that failed to meet the 60% minimum sperm motility requirement tended (P = 0.07) to be greater in the -RFI group than in the +RFI group (10.2% vs. 4.4%, respectively). In a subpopulation of 115 bulls, individual progressive sperm motility was greater (P < 0.05) in +RFI (85%) than -RFI (80%) bulls. A multisire natural mating experiment was conducted during 2 consecutive breeding seasons (2006 to 2007 and 2007 to 2008) using 18 +RFI and 18 -RFI bulls. The overall calving rate (calves born/cows exposed) was 72.9%. Mean number of progeny per sire was significantly greater (P < 0.01) in -RFI bulls (18.3) than in +RFI bulls (11.8). Selection for feed efficiency based on RFI appears to have no detrimental impact on reproductive performance and fertility in beef bulls bred in multisire groups on pasture. However, the decreased sperm motility and the greater number of progeny per sire associated with -RFI status need further investigation.

A 25 years experience of group-housed sows–reproduction in animal welfare-friendly systems

PubMed Central

2014-01-01

Since January 1 2013, group housing of sows has been compulsory within the European Union (EU) in all pig holdings with more than ten sows. Sows and gilts need to be kept in groups from 4 weeks after service to 1 week before the expected time of farrowing (Article 3(4) of Directive 2008/120/EC on the protection of pigs). The legislation regarding group housing was adopted already in 2001 and a long transitional period was allowed to give member states and producers enough time for adaptation. Even so, group housing of sows still seems to be uncommon in the EU, and is also uncommon in commercial pig farming systems in the rest of the world. In this review we share our experience of the Swedish 25 years of animal welfare legislation stipulating that sows must be loose-housed which de facto means group housed. The two most important concerns related to reproductive function among group-housed sows are the occurrence of lactational oestrus when sows are group-housed during lactation, and the stress that is associated with group housing during mating and gestation. Field and clinical observations in non-lactating, group-housed sows in Sweden suggest that by making basic facts known about the pig reproductive physiology related to mating, we might achieve application of efficient batch-wise breeding without pharmacological interventions. Group housing of lactating sows has some production disadvantages and somewhat lower productivity would likely have to be expected. Recordings of behavioural indicators in different housing systems suggest a lower welfare level in stalled animals compared with group-housed ones. However, there are no consistent effects on the reproductive performance associated with different housing systems. Experimental studies suggest that the most sensitive period, regarding disturbance of reproductive functions by external stressors, is the time around oestrus. We conclude that by keeping sows according to the pig welfare-friendly Directive 2008/120/EC, it is possible to combine group-housing of sows with good reproductive performance and productivity. However, substantially increased research and development is needed to optimize these systems. PMID:24910081

Broodstock management and hormonal manipulations of fish reproduction.

PubMed

Mylonas, Constantinos C; Fostier, Alexis; Zanuy, Silvia

2010-02-01

Control of reproductive function in captivity is essential for the sustainability of commercial aquaculture production, and in many fishes it can be achieved by manipulating photoperiod, water temperature or spawning substrate. The fish reproductive cycle is separated in the growth (gametogenesis) and maturation phase (oocyte maturation and spermiation), both controlled by the reproductive hormones of the brain, pituitary and gonad. Although the growth phase of reproductive development is concluded in captivity in most fishes-the major exemption being the freshwater eel (Anguilla spp.), oocyte maturation (OM) and ovulation in females, and spermiation in males may require exogenous hormonal therapies. In some fishes, these hormonal manipulations are used only as a management tool to enhance the efficiency of egg production and facilitate hatchery operations, but in others exogenous hormones are the only way to produce fertilized eggs reliably. Hormonal manipulations of reproductive function in cultured fishes have focused on the use of either exogenous luteinizing hormone (LH) preparations that act directly at the level of the gonad, or synthetic agonists of gonadotropin-releasing hormone (GnRHa) that act at the level of the pituitary to induce release of the endogenous LH stores, which, in turn act at the level of the gonad to induce steroidogenesis and the process of OM and spermiation. After hormonal induction of maturation, broodstock should spawn spontaneously in their rearing enclosures, however, the natural breeding behavior followed by spontaneous spawning may be lost in aquaculture conditions. Therefore, for many species it is also necessary to employ artificial gamete collection and fertilization. Finally, a common question in regards to hormonal therapies is their effect on gamete quality, compared to naturally maturing or spawning broodfish. The main factors that may have significant consequences on gamete quality-mainly on eggs-and should be considered when choosing a spawning induction procedure include (a) the developmental stage of the gonads at the time the hormonal therapy is applied, (b) the type of hormonal therapy, (c) the possible stress induced by the manipulation necessary for the hormone administration and (d) in the case of artificial insemination, the latency period between hormonal stimulation and stripping for in vitro fertilization. Copyright 2009 Elsevier Inc. All rights reserved.

Population dynamics with a mixed type of sexual and asexual reproduction in a fluctuating environment

PubMed Central

2012-01-01

Background Carassius gibelio, a cyprinid fish from Eurasia, has the ability to reproduce both sexually and asexually. This fish is also known as an invasive species which colonized almost all continental Europe, most likely originating from Asia and Eastern Europe. Populations of both sexually and asexually reproducing individuals exist in sympatry. In this study we try to elucidate the advantages of such a mixed type of reproduction. We investigate the dynamics of two sympatric populations with sexual and asexual reproduction in a periodically fluctuating environment. We define an individual-based computational model in which genotypes are represented by L loci, and the environment is composed of L resources for which the two populations compete. Results Our model demonstrates advantageous population dynamics where the optimal percentage of asexual reproduction depends on selection strength, on the number of selected loci and on the timescale of environmental fluctuations. We show that the sexual reproduction is necessary for "generating" fit genotypes, while the asexual reproduction is suitable for "amplifying" them. The simulations show that the optimal percentage of asexual reproduction increases with the length of the environment stability period and decrease with the strength of the selection and the number of loci. Conclusions In this paper we addressed the advantages of a mixed type of sexual and asexual reproduction in a changing environment and explored the idea that a species that is able to adapt itself to environmental fluctuation can easily colonize a new habitat. Our results could provide a possible explanation for the rapid and efficient invasion of species with a variable ratio of sexual and asexual reproduction such as Carassius gibelio. PMID:22489797

[In vitro development and chimeric efficiency of mouse-porcine interspecies chimeric embryos in different culture systems].

PubMed

Wang, Ying; Ren, Jilong; Song, Yuran; Hai, Tang; Zhou, Qi; Liu, Zhonghua

2016-07-25

With the advancements of stem cells and regenerative medicine, interspecies chimera has become a hot topic and will pave a new way of providing donor sources in organ transplantation. However, the interspecies chimera is confronted with a number of scientific questions and technical obstacles, including selections of appropriate embryonic stage and appropriate culture medium; those factors will deeply influence the developmental balance between donor cells and receptor embryos. Due to its relatively rapid reproductive cycle and similar organ size to human's, porcine is a very potential donor candidate to study these questions. To compare the development and chimeric efficiency of interspecies embryos, we tested and evaluated three different culture systems, PZM-3 (Porcine zygotic medium), culture medium for iPSCs (N2B27) and 3.5 h of N2B27 before PZM-3 (N2B27(3.5 h)), and two different embryonic stages, 8-cell and blastocyst in mouse-porcine chimeric embryos using parthenogenetically activated porcine embryos and mouse induced pluripotent stem cells (miPS). The results showed that, PZM-3 was beneficial for both development of chimeric embryos and miPSCs proliferation in porcine embryos in the 8-cell injection group. After early blastocyst injection, the chimeric efficiency did not appear significantly different among the three culture systems but was lower than 8-cell injection. In summary, the results suggest that 8-cell injection and PZM-3 culture medium are more beneficial to the in vitro development and chimeric efficiency of mouse-porcine chimeric embryos.

Ensuring the inclusion of sexual and reproductive health and rights under a sustainable development goal on health in the post-2015 human rights framework for development.

PubMed

Haslegrave, Marianne

2013-11-01

Since the 1994 International Conference on Population and Development (ICPD) in Cairo placed reproductive health and rights firmly on the international agenda, civil society and other advocates have worked ceaselessly to ensure that they remain central to women's empowerment and have taken all opportunities to expand the framework to include sexual health and rights. When the development process changed with the introduction of the Millennium Development Goals (MDGs) in 2000, sexual and reproductive health and rights were excluded, and only in 2007 was universal access to reproductive health added back in. In 2014 and 2015, the future of ICPD Beyond 2014, the MDGs and the post-2015 development framework will be decided, following consultations and meetings across the globe. This paper takes stock of the key influences on efforts to achieve the ICPD agenda and summarises the past, current and planned future events, reports and processes between 1994 and 2014, leading up to the determination of the post-2015 development framework and sustainable development goals. It concludes that the one thing we cannot afford to allow is what happened with the MDGs in 2000. We must not leave the room empty-handed, but must instead ensure the inclusion of sexual and reproductive health and rights as a priority under a new health goal. Copyright © 2013 Reproductive Health Matters. Published by Elsevier Ltd. All rights reserved.

NTP-CERHR Monograph on the Potential Human Reproductive and Developmental Effects of Di-n-Butyl Phthalate (DBP).

PubMed

2003-04-01

TThe National Toxicology Program (NTP) Center for the Evaluation of Risks to Human Reproduction (CERHR) conducted an evaluation of the potential for di-n-butyl phthalate (DBP) to cause adverse effects on reproduction and development in humans. DBP is one of 7 phthalate chemicals evaluated by the NTP CERHR Phthalates Expert Panel. These phthalates were selected for evaluation because of high production volume, extent of human exposures, use in children's products, and/or published evidence of reproductive or developmental toxicity. Unlike many phthalates, DBP is not currently used as a plasticizer in polyvinyl chloride plastics. DBP is a component of latex adhesives and is used in cosmetics and other personal care products, as a plasticizer in cellulose plastics, and as a solvent for dyes. The results of this evaluation on DBP are published in a NTP-CERHR monograph which includes: 1) the NTP Brief, 2) the Expert Panel Report on the Reproductive and Developmental Toxicity of Di-n-Butyl Phthalate, and 3) public comments received on the Expert Panel Report. As stated in the NTP Brief, the NTP reached the following conclusions regarding the possible effects of exposure to DBP on human development and reproduction. First, although DBP could possibly affect human reproduction and development if exposures are sufficiently high, the NTP concludes that there is negligible concern for reproductive toxicity in exposed adults. Second, the NTP concludes that there is minimal concern for developmental effects when pregnant women are exposed to DBP levels estimated by the panel (2-10 mug/kg body weight/day). There is no direct evidence that exposure of people to DBP adversely affects reproduction or development, but studies reviewed by the expert panel show that oral exposure to high doses of DBP (>/=100 mg/kg body weight/day) may adversely affect the prenatal and early postnatal development in rodents. Finally, based on exposure estimates in women of reproductive age, the NTP concludes that there is some concern for DBP causing adverse effects to human development, particularly development of the male reproductive system. NTP-CERHR monographs are transmitted to federal and state agencies, interested parties, and the public and are available electronically in PDF format on the CERHR web site (http://cerhr.niehs.nih.gov) and in printed text or CD-ROM from the CERHR (National Institute of Environmental Health Sciences, P.O. Box 12233, MD EC-32, Research Triangle Park, NC; fax: 919-316-4511).

Norwegian honey bees surviving Varroa destructor mite infestations by means of natural selection.

PubMed

Oddie, Melissa A Y; Dahle, Bjørn; Neumann, Peter

2017-01-01

Managed, feral and wild populations of European honey bee subspecies, Apis mellifera , are currently facing severe colony losses globally. There is consensus that the ectoparasitic mite Varroa destructor , that switched hosts from the Eastern honey bee Apis cerana to the Western honey bee A. mellifera , is a key factor driving these losses. For >20 years, breeding efforts have not produced European honey bee colonies that can survive infestations without the need for mite control. However, at least three populations of European honey bees have developed this ability by means of natural selection and have been surviving for >10 years without mite treatments. Reduced mite reproductive success has been suggested as a key factor explaining this natural survival. Here, we report a managed A. mellifera population in Norway, that has been naturally surviving consistent V. destructor infestations for >17 years. Surviving colonies and local susceptible controls were evaluated for mite infestation levels, mite reproductive success and two potential mechanisms explaining colony survival: grooming of adult worker bees and Varroa Sensitive Hygiene (VSH): adult workers specifically detecting and removing mite-infested brood. Mite infestation levels were significantly lower in surviving colonies and mite reproductive success was reduced by 30% when compared to the controls. No significant differences were found between surviving and control colonies for either grooming or VSH. Our data confirm that reduced mite reproductive success seems to be a key factor for natural survival of infested A. mellifera colonies. However, neither grooming nor VSH seem to explain colony survival. Instead, other behaviors of the adult bees seem to be sufficient to hinder mite reproductive success, because brood for this experiment was taken from susceptible donor colonies only. To mitigate the global impact of V. destructor , we suggest learning more from nature, i.e., identifying the obviously efficient mechanisms favored by natural selection.

Norwegian honey bees surviving Varroa destructor mite infestations by means of natural selection

PubMed Central

Dahle, Bjørn; Neumann, Peter

2017-01-01

Background Managed, feral and wild populations of European honey bee subspecies, Apis mellifera, are currently facing severe colony losses globally. There is consensus that the ectoparasitic mite Varroa destructor, that switched hosts from the Eastern honey bee Apis cerana to the Western honey bee A. mellifera, is a key factor driving these losses. For >20 years, breeding efforts have not produced European honey bee colonies that can survive infestations without the need for mite control. However, at least three populations of European honey bees have developed this ability by means of natural selection and have been surviving for >10 years without mite treatments. Reduced mite reproductive success has been suggested as a key factor explaining this natural survival. Here, we report a managed A. mellifera population in Norway, that has been naturally surviving consistent V. destructor infestations for >17 years. Methods Surviving colonies and local susceptible controls were evaluated for mite infestation levels, mite reproductive success and two potential mechanisms explaining colony survival: grooming of adult worker bees and Varroa Sensitive Hygiene (VSH): adult workers specifically detecting and removing mite-infested brood. Results Mite infestation levels were significantly lower in surviving colonies and mite reproductive success was reduced by 30% when compared to the controls. No significant differences were found between surviving and control colonies for either grooming or VSH. Discussion Our data confirm that reduced mite reproductive success seems to be a key factor for natural survival of infested A. mellifera colonies. However, neither grooming nor VSH seem to explain colony survival. Instead, other behaviors of the adult bees seem to be sufficient to hinder mite reproductive success, because brood for this experiment was taken from susceptible donor colonies only. To mitigate the global impact of V. destructor, we suggest learning more from nature, i.e., identifying the obviously efficient mechanisms favored by natural selection. PMID:29085753

Effects of Perinatal Polychlorinated Biphenyls on Adult Female Rat Reproduction: Development, Reproductive Physiology, and Second Generational Effects

PubMed Central

Steinberg, Rebecca M.; Walker, Deena M.; Juenger, Thomas E.; Woller, Michael J.; Gore, Andrea C.

2009-01-01

Perinatal exposures to endocrine-disrupting chemicals such as polychlorinated biphenyls (PCBs) can cause latent effects on reproductive function. Here, we tested whether PCBs administered during late pregnancy would compromise reproductive physiology in both the fetally-exposed female offspring (F1 generation), as well as in their female offspring (F2 generation). Pregnant Sprague-Dawley rats were treated with the PCB mixture Aroclor (A) 1221 (0, 0.1, 1 or 10 mg/kg) on embryonic days 16 and 18. Somatic and reproductive development of F1 and their F2 female offspring were monitored, including ages of eye opening, pubertal landmarks, and serum reproductive hormones. The results showed that low doses of A1221 given during this critical period of neuroendocrine development caused differential effects of A1221 on F1 and F2 female rats. In both generations, litter sex ratio was skewed towards females. In the F1 generation, additional effects were found including a significant alteration of serum luteinizing hormone (LH) in the 1 mg/kg A1221 group. The F2 generation showed more profound alterations, particularly with respect to fluctuations in hormones and reproductive tract tissues across the estrous cycle. On proestrus, the day of the preovulatory GnRH/gonadotropin surge, F2 females whose mothers had been perinatally exposed to A1221 exhibited substantially suppressed LH and progesterone concentrations, and correspondingly smaller uterine and ovarian weights on estrus, compared to F2 decendants of control rats. These latter changes suggest a dysregulation of reproductive physiology. Thus, low levels of exposure to PCBs during late fetal development cause significant consequences on the maturation and physiology of two generations of female offspring. These findings have implications for reproductive health and fertility of wildlife and humans. PMID:18305224

The evolution of reproductive diversity in Afrobatrachia: A phylogenetic comparative analysis of an extensive radiation of African frogs

PubMed Central

Portik, Daniel M.; Blackburn, David C.

2016-01-01

The reproductive modes of anurans (frogs and toads) are the most diverse of terrestrial vertebrates, and a major challenge is identifying selective factors that promote the evolution or retention of reproductive modes across clades. Terrestrialized anuran breeding strategies have evolved repeatedly from the plesiomorphic fully aquatic reproductive mode, a process thought to occur through intermediate reproductive stages. Several selective forces have been proposed for the evolution of terrestrialized reproductive traits, but factors such as water systems and co‐evolution with ecomorphologies have not been investigated. We examined these topics in a comparative phylogenetic framework using Afrobatrachian frogs, an ecologically and reproductively diverse clade representing more than half of the total frog diversity found in Africa (∼400 species). We infer direct development has evolved twice independently from terrestrialized reproductive modes involving subterranean or terrestrial oviposition, supporting evolution through intermediate stages. We also detect associations between specific ecomorphologies and oviposition sites, and demonstrate arboreal species exhibit an overall shift toward using lentic water systems for breeding. These results indicate that changes in microhabitat use associated with ecomorphology, which allow access to novel sites for reproductive behavior, oviposition, or larval development, may also promote reproductive mode diversity in anurans. PMID:27402182

Prebiological evolution and the metabolic origins of life.

PubMed

Pratt, Andrew J

2011-01-01

The chemoton model of cells posits three subsystems: metabolism, compartmentalization, and information. A specific model for the prebiological evolution of a reproducing system with rudimentary versions of these three interdependent subsystems is presented. This is based on the initial emergence and reproduction of autocatalytic networks in hydrothermal microcompartments containing iron sulfide. The driving force for life was catalysis of the dissipation of the intrinsic redox gradient of the planet. The codependence of life on iron and phosphate provides chemical constraints on the ordering of prebiological evolution. The initial protometabolism was based on positive feedback loops associated with in situ carbon fixation in which the initial protometabolites modified the catalytic capacity and mobility of metal-based catalysts, especially iron-sulfur centers. A number of selection mechanisms, including catalytic efficiency and specificity, hydrolytic stability, and selective solubilization, are proposed as key determinants for autocatalytic reproduction exploited in protometabolic evolution. This evolutionary process led from autocatalytic networks within preexisting compartments to discrete, reproducing, mobile vesicular protocells with the capacity to use soluble sugar phosphates and hence the opportunity to develop nucleic acids. Fidelity of information transfer in the reproduction of these increasingly complex autocatalytic networks is a key selection pressure in prebiological evolution that eventually leads to the selection of nucleic acids as a digital information subsystem and hence the emergence of fully functional chemotons capable of Darwinian evolution.

Three-dimensional imaging of the developing mouse female reproductive organs with optical coherence tomography

NASA Astrophysics Data System (ADS)

Burton, Jason C.; Wang, Shang; Behringer, Richard R.; Larina, Irina V.

2016-03-01

Infertility is a known major health concern and is estimated to impact ~15% of couples in the U.S. The majority of failed pregnancies occur before or during implantation of the fertilized embryo into the uterus. Understanding the mechanisms regulating development by studying mouse reproductive organs could significantly contribute to an improved understanding of normal development of reproductive organs and developmental causes of infertility in humans. Towards this goal, we report a three-dimensional (3D) imaging study of the developing mouse reproductive organs (ovary, oviduct, and uterus) using optical coherence tomography (OCT). In our study, OCT was used for 3D imaging of reproductive organs without exogenous contrast agents and provides micro-scale spatial resolution. Experiments were conducted in vitro on mouse reproductive organs ranging from the embryonic day 14.5 to adult stages. Structural features of the ovary, oviduct, and uterus are presented. Additionally, a comparison with traditional histological analysis is illustrated. These results provide a basis for a wide range of infertility studies in mouse models. Through integration with traditional genetic and molecular biology approaches, this imaging method can improve understanding of ovary, oviduct, and uterus development and function, serving to further contribute to our understanding of fertility and infertility.

Colour change in a structural ornament is related to individual quality, parasites and mating patterns in the blue tit

NASA Astrophysics Data System (ADS)

Badás, E. P.; Martínez, J.; Rivero-de Aguilar, J.; Ponce, C.; Stevens, M.; Merino, S.

2018-02-01

Carry-over effects refer to processes that occur in one season and influence fitness in the following. In birds, two costly activities, namely reproduction and moult, are restricted to a small time window, and sometimes overlap. Thus, colour in newly moulted feathers is likely to be affected by the costs of reproduction. Using models of bird vision we investigated male colour change in a free-living population of blue tits ( Cyanistes caeruleus) in three sampling occasions: spring 1, winter and spring 2. We related crown, tail, breast and cheek feather colouration after the moult (winter) to the intensity of infections by blood parasites during reproduction (spring 1). In the following spring (spring 2), we explored mating patterns with respect to changes in feather colour (springs 1 vs. 2). Males that were less intensely infected by the malaria parasite Plasmodium while breeding showed purer white cheek feathers in winter, which may indicate higher feather quality. Increased brightness in the white cheek was associated with better body condition during reproduction. In the following season, males with brighter cheeks paired with females that had noticeably brighter cheek patches compared to the male's previous mate. These results suggest that the conditions experienced during reproduction are likely to affect moult and thus feather colouration, at least in the white patch. High quality individuals may allocate resources efficiently during reproduction increasing future reproductive success through variation in mating patterns. Carry-over effects from reproduction might extend not only to the non-breeding phase, but also to the following breeding season.

Colour change in a structural ornament is related to individual quality, parasites and mating patterns in the blue tit.

PubMed

Badás, E P; Martínez, J; Rivero-de Aguilar, J; Ponce, C; Stevens, M; Merino, S

2018-02-06

Carry-over effects refer to processes that occur in one season and influence fitness in the following. In birds, two costly activities, namely reproduction and moult, are restricted to a small time window, and sometimes overlap. Thus, colour in newly moulted feathers is likely to be affected by the costs of reproduction. Using models of bird vision we investigated male colour change in a free-living population of blue tits (Cyanistes caeruleus) in three sampling occasions: spring 1, winter and spring 2. We related crown, tail, breast and cheek feather colouration after the moult (winter) to the intensity of infections by blood parasites during reproduction (spring 1). In the following spring (spring 2), we explored mating patterns with respect to changes in feather colour (springs 1 vs. 2). Males that were less intensely infected by the malaria parasite Plasmodium while breeding showed purer white cheek feathers in winter, which may indicate higher feather quality. Increased brightness in the white cheek was associated with better body condition during reproduction. In the following season, males with brighter cheeks paired with females that had noticeably brighter cheek patches compared to the male's previous mate. These results suggest that the conditions experienced during reproduction are likely to affect moult and thus feather colouration, at least in the white patch. High quality individuals may allocate resources efficiently during reproduction increasing future reproductive success through variation in mating patterns. Carry-over effects from reproduction might extend not only to the non-breeding phase, but also to the following breeding season.

Environmental and genetic correlates of allocation to sexual reproduction in the circumpolar plant Bistorta vivipara.

PubMed

Bills, John W; Roalson, Eric H; Busch, Jeremiah W; Eidesen, Pernille B

2015-07-01

• Sexual reproduction often requires more energy and time than clonal reproduction. In marginal arctic conditions, species that can reproduce both sexually and clonally dominate. Plants with this capacity may thrive because they can alter reproduction depending on environmental conditions. Bistorta vivipara is a circumpolar herb that predominately reproduces clonally, but certain environmental conditions promote higher investment in flowers (and possible sexual reproduction). Despite largely reproducing clonally, the herb has high levels of genetic variation, and the processes underlying this paradoxical pattern of variation remain unclear. Here we identified environmental factors associated with sexual investment and examined whether sexual reproduction is associated with higher levels of genetic variation.• We sampled 20 populations of B. vivipara across the high Arctic archipelago of Svalbard. In each population, we measured reproductive traits, environmental variables, and collected samples for genetic analyses. These samples permitted hypotheses to be tested regarding sexual investment and ecological and genetic correlates.• Increased soil nitrogen and organic matter content and decreased elevation were positively associated with investment in flowers. Increased investment in flowers significantly correlated with more genotypes per population. Linkage disequilibrium was consistent with predominant clonality, but several populations showed higher genetic variation and lower differentiation than expected. There was no geographical genetic structure.• In B. vivipara, sexual investment is positively associated with habitat quality. Bistorta vivipara predominantly reproduces clonally, but occasional outcrossing, efficient clonal reproduction, and dispersal by bulbils can explain the considerable genetic variation and weak genetic structure in B. vivipara. © 2015 Botanical Society of America, Inc.

Reproductive effects on skeletal health in Shuar women of Amazonian Ecuador: a life history perspective.

PubMed

Madimenos, Felicia C; Snodgrass, J Josh; Liebert, Melissa A; Cepon, Tara J; Sugiyama, Lawrence S

2012-01-01

Clinical and epidemiological research suggest that bone mineral density (BMD) in women is shaped by various reproductive factors such as parity and lactation patterns. However, the extent of these effects on BMD remains unclear because of contradictory findings and a focus on industrialized populations. Because fertility patterns in these groups are vastly different than those of women from non-Western, subsistence populations, our current understanding of the reproductive effects on skeletal health is incomplete. Using a life history perspective, this study examines the relationship between reproductive factors and bone density among women from the Indigenous Shuar population, an Amazonian Ecuadorian forager-horticulturalist group. This preliminary, cross-sectional study included 130 premenopausal and postmenopausal women (14-86 years old) from the Morona-Santiago region of Ecuador. Anthropometrics were recorded, as was estimated BMD using a calcaneal ultrasonometer. A reproductive history questionnaire was administered that included questions regarding menarche, parity, lactation patterns, and menopause. Among postmenopausal women, early menarche and greater stature were significantly associated with higher bone density values. Among premenopausal women, few significant relationships between bone values and reproductive variables were documented; effects of lactation appeared to be transient and restored following weaning. Although preliminary and not based on longitudinal data, these findings suggest that the effects of reproduction are transient as the system of calcium homeostasis in premenopausal women efficiently restores the bone loss that results from metabolically active reproductive states. Further, this research suggests that the timing of early life history events may canalize bone density phenotype. Copyright © 2012 Wiley Periodicals, Inc.

Angiogenesis and microvasculature in the female reproductive organs: physiological and pathological implications.

PubMed

Shimizu, Takashi; Hoshino, Yumi; Miyazaki, Hitoshi; Sato, Eimei

2012-01-01

The female reproductive organs such as ovary, uterus, and placenta are some of the few adult tissues that exhibit regular intervals of rapid growth, and are highly vascularized and have high rates of blood flow. Angiogenesis is a process of vascular growth that is mainly limited to the reproductive system in healthy adult animals. The development of new blood vessels in the ovary and uterus is essential to guarantee the necessary supply of nutrients and hormones. The genetic and molecular mechanisms that control the development of capillary blood vessels in the reproductive organs are beginning to be elucidated. Reproductive organs contain and produce angiogenic factors which may act alone or in concert to regulate the process of vasculature. Vascular endothelial growth factors (VEGFs) and fibroblast growth factor (FGFs) are key factors for vascular system in the reproductive organs. Recent numerous studies reported several roles of VEGFs and FGFs on ovarian and uterine functions. In this review, we focus on the involvement of VEGFs and FGFs as angiogenic factors on reproductive organs and vascular therapy for diseases of reproductive organs using anti-angiogenic agents.

Impact of endocrine disrupting chemicals on onset and development of female reproductive disorders and hormone-related cancer.

PubMed

Scsukova, Sona; Rollerova, Eva; Bujnakova Mlynarcikova, Alzbeta

2016-12-01

A growing body of evidence suggests that exposure to chemical substances designated as endocrine disrupting chemicals (EDCs) due to their ability to disturb endocrine (hormonal) activity in humans and animals, may contribute to problems with fertility, pregnancy, and other aspects of reproduction. The presence of EDCs has already been associated with reproductive malfunction in wildlife species, but it remains difficult to prove causal relationships between the presence of EDCs and specific reproductive problems in vivo, especially in females. On the other hand, the increasing number of experiments with laboratory animals and in vitro research indicate the ability of different EDCs to influence the normal function of female reproductive system, and even their association with cancer development or progression. Research shows that EDCs may pose the greatest risk during prenatal and early postnatal development when organ and neural systems are forming. In this review article, we aim to point out a possible contribution of EDCs to the onset and development of female reproductive disorders and endocrine-related cancers with regard to the period of exposure to EDCs and affected endpoints (organs or processes). Copyright © 2016. Published by Elsevier Urban & Partner Sp. z o.o.

In vitro development of Haemoproteus parasites: the efficiency of reproductive cells increase during simultaneous sexual process of different lineages.

PubMed

Valkiūnas, Gediminas; Palinauskas, Vaidas; Ilgūnas, Mikas; Bernotienė, Rasa; Iezhova, Tatjana A

2014-04-01

Recent in vitro experimental studies reported the complex patterns of haemosporidian (Haemosporida) between-lineage interactions, which prevent mixing of lineages during simultaneous sexual process. Numerous anomalous ookinetes have been observed; these are not involved in sporogony. Massive development of such ookinetes might influence parasite transmission but is insufficiently investigated. The simultaneous sexual process of several lineages is a common phenomenon in vectors due to high prevalence of haemosporidian co-infections in wildlife. It remains unclear if the number of anomalous ookinetes changes during dual-infection sporogony in comparison with the single-infection process. We calculated proportions of the anomalous and normal ookinetes, which developed during single-infection (control) and dual-infection experiments in vitro conditions. Three mitochondrial cytochrome b lineages belonging to three Haemoproteus spp. (Haemosporida, Haemoproteidae) were isolated from naturally infected passerine birds. Sexual process and ookinete development were initiated in vitro by mixing blood containing mature gametocytes of two different parasites; the following experiments were performed: (1) Haemoproteus tartakovskyi (lineage hSISKIN1) × Haemoproteus lanii (lineage hRBS4) and (2) Haemoproteus belopolskyi (hHIICT3) × H. lanii (hRBS4). Genetic difference between lineages was 5.0-5.9%. Normal and anomalous ookinetes developed in all control and dual-infection experiments. The number of anomalous ookinetes markedly decreased, and normal ookinetes increased in all dual-infection experiments in comparison with those in controls, except for H. belopolskyi, in which proportion of the anomalous and normal ookinetes did not change. This study shows that simultaneous sexual process of two genetically distant lineages of haemosporidian parasites might increase the efficiency of reproductive cells, resulting in the development of a greater number of normal ookinetes. The marked increase of the number of normal ookinetes, which is involved in sporogony, indicates the success of sporogony in dual infections. Some haemosporidian lineages might benefit from simultaneous sporogony. Widespread avian Haemoproteus spp. are convenient and laboratory-friendly organisms for in vitro experimental research addressing between-lineage interaction in parasites during the sexual process.

Vouchers for family planning and sexual and reproductive health services: a review of voucher programs involving Marie Stopes International among 11 Asian and African countries.

PubMed

Eva, Gillian; Quinn, Andrew; Ngo, Thoai D

2015-08-01

To evaluate provision of vouchers for family planning and sexual and reproductive health (SRH) services. A review was conducted to assess the effects of 24 voucher programs in Marie Stopes International programs across 11 countries in Asia and Africa between 2005 and the present. The outcome measures were uptake of services; service use among specific subgroups; user satisfaction with service quality; and efficiency of service delivery. Twelve of the 24 programs covered family planning only, whereas the other 12 programs covered family planning and/or SRH. Service uptake increased following implementation, although voucher redemption rates varied by program (44.1%-92.4%). Most programs were successful in reaching subgroups, such as the poor and young (under 25years), although this outcome depended on the targeting approach. Most programs recorded high user satisfaction; however, the evidence regarding efficiency was mixed. Vouchers increased uptake of services and, in some cases, improved service quality and reach to specific groups. Nevertheless, robust evaluation designs are required to measure efficiency. Copyright © 2015. Published by Elsevier Ireland Ltd.

Effects of dietary omega-3/omega-6 fatty acid ratios on reproduction in the young breeder rooster.

PubMed

Feng, Yun; Ding, Yu; Liu, Juan; Tian, Ye; Yang, Yanzhou; Guan, Shuluan; Zhang, Cheng

2015-03-21

Polyunsaturated fatty acids (PUFAs) are necessary for the body's metabolism, growth and development. Although PUFAs play an important role in the regulation of reproduction, their role in testis development in the rooster is unknown. The present study was conducted to investigate the effects of omega-3/omega-6 (n-3/n-6, PUFAs) ratios on reproductive performance in young breeder roosters. Plasma levels of reproductive hormones, testis development, and reproductive hormone receptor and StAR mRNA expression were also assessed. Although PUFAs (n-3/n-6: 1/4.15) had no significant effect on the testis index (P > 0.05), the spermatogonial development and germ cell layers were increased. Moreover, serum levels of hormones (GnRH, FSH, LH and T) on day 35 were also significantly increased by PUFAs (n-3/n-6: 1/4.15). To investigate whether PUFAs regulate the expression of hormone receptors and StAR, real time-PCR was used to measure GnRHR, FSHR, LHR and StAR mRNA levels. PUFAs significantly increased the mRNA levels of all of these genes. These results indicate that PUFAs enhance the reproductive performance of young roosters by increasing hormone secretion and function, the latter by up-regulating receptor expression. These findings provide a sound basis for a balanced n-3/n-6 PUFA ratio being beneficial to young rooster reproduction.

Heterochronic expression of sexual reproductive programs during apomictic development in Tripsacum.

PubMed Central

Grimanelli, Daniel; García, Marcelina; Kaszas, Etienne; Perotti, Enrico; Leblanc, Olivier

2003-01-01

Some angiosperms reproduce by apomixis, a natural way of cloning through seeds. Apomictic plants bypass both meiosis and egg cell fertilization, producing progeny that are genetic replicas of the mother plant. In this report, we analyze reproductive development in Tripsacum dactyloides, an apomictic relative of maize, and in experimental apomictic hybrids between maize and Tripsacum. We show that apomictic reproduction is characterized by an alteration of developmental timing of both sporogenesis and early embryo development. The absence of female meiosis in apomictic Tripsacum results from an early termination of female meiosis. Similarly, parthenogenetic development of a maternal embryo in apomicts results from precocious induction of early embryogenesis events. We also show that male meiosis in apomicts is characterized by comparable asynchronous expression of developmental stages. Apomixis thus results in an array of possible phenotypes, including wild-type sexual development. Overall, our observations suggest that apomixis in Tripsacum is a heterochronic phenotype; i.e., it relies on a deregulation of the timing of reproductive events, rather than on the alteration of a specific component of the reproductive pathway. PMID:14668399

Reflections on the reproductive sciences in agriculture in the UK and US, ca. 1900-2000+.

PubMed

Clarke, Adele E

2007-06-01

This paper provides a brief comparative overview of the development of the reproductive sciences especially in agriculture in the UK and the US. It begins with the establishment by F. H. A. Marshall in 1910 of the boundaries that framed the reproductive sciences as distinct from genetics and embryology. It then examines how and where the reproductive sciences were taken up in agricultural research settings, focusing on the differential development of US and UK institutions. The reproductive sciences were also pursued in medical and biological settings, and I discuss how the intersections among all three allowed the circulation of both ideas and scientists' careers. Across the twentieth century, scientific leadership in the reproductive sciences alternated between the UK and US, and these patterns are elucidated. I conclude with thoughts on future research that might emphasize the elaboration of industrialization processes in agriculture and new capacities to transform both reproductive processes and their products--life itself--as biopower comes to be more ambitiously understood as extending across all species.

Current issues in medically assisted reproduction and genetics in Europe: research, clinical practice, ethics, legal issues and policy.

PubMed

Harper, Joyce; Geraedts, Joep; Borry, Pascal; Cornel, Martina C; Dondorp, Wybo J; Gianaroli, Luca; Harton, Gary; Milachich, Tanya; Kääriäinen, Helena; Liebaers, Inge; Morris, Michael; Sequeiros, Jorge; Sermon, Karen; Shenfield, Françoise; Skirton, Heather; Soini, Sirpa; Spits, Claudia; Veiga, Anna; Vermeesch, Joris Robert; Viville, Stéphane; de Wert, Guido; Macek, Milan

2014-08-01

How has the interface between genetics and assisted reproduction technology (ART) evolved since 2005? The interface between ART and genetics has become more entwined as we increase our understanding about the genetics of infertility and we are able to perform more comprehensive genetic testing. In March 2005, a group of experts from the European Society of Human Genetics and European Society of Human Reproduction and Embryology met to discuss the interface between genetics and ART and published an extended background paper, recommendations and two Editorials. An interdisciplinary workshop was held, involving representatives of both professional societies and experts from the European Union Eurogentest2 Coordination Action Project. In March 2012, a group of experts from the European Society of Human Genetics, the European Society of Human Reproduction and Embryology and the EuroGentest2 Coordination Action Project met to discuss developments at the interface between clinical genetics and ART. As more genetic causes of reproductive failure are now recognized and an increasing number of patients undergo testing of their genome prior to conception, either in regular health care or in the context of direct-to-consumer testing, the need for genetic counselling and PGD may increase. Preimplantation genetic screening (PGS) thus far does not have evidence from RCTs to substantiate that the technique is both effective and efficient. Whole genome sequencing may create greater challenges both in the technological and interpretational domains, and requires further reflection about the ethics of genetic testing in ART and PGD/PGS. Diagnostic laboratories should be reporting their results according to internationally accepted accreditation standards (ISO 15189). Further studies are needed in order to address issues related to the impact of ART on epigenetic reprogramming of the early embryo. The legal landscape regarding assisted reproduction is evolving, but still remains very heterogeneous and often contradictory. The lack of legal harmonization and uneven access to infertility treatment and PGD/PGS fosters considerable cross-border reproductive care in Europe, and beyond. This continually evolving field requires communication between the clinical genetics and IVF teams and patients to ensure that they are fully informed and can make well-considered choices. Funding was received from ESHRE, ESHG and EuroGentest2 European Union Coordination Action project (FP7 - HEALTH-F4-2010-26146) to support attendance at this meeting. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

GENOMIC AND PROTEOMIC TECHNIQUES APPLIED TO REPRODUCTIVE BIOLOGY

EPA Science Inventory

Genomic and proteomic techniques applied to reproductive biology
John C. Rockett
Reproductive Toxicology Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, United States Environmental Protection Agency, Research Tria...

Transrectal ultrasound evaluation in tropical dairy goats: an indispensable tool for the diagnosis of reproductive disorders.

PubMed

Maia, A L R S; Brandão, F Z; Souza-Fabjan, J M G; Veiga, M O; Balaro, M F A; Facó, O; Fonseca, J F

2018-04-01

In Brazil, great milk productivity was achieved after the implementation of a genetic improvement program. However, reproductive efficiency is still far from optimal, possibly due to the high number of undiagnosed disorders that may affect fertility. The aim of this study was to evaluate occurrences of the main reproductive disorders in dairy goats in southeastern Brazil. Data were collected between January 2015 and May 2017 from 23 commercial herds of different breeds, with goats ranging from 8 months to 12 years of age. Transrectal ultrasound exams were performed in 2680 goats. A total of 14.8% of the does showed a disorder in the reproductive tract: hydrometra (10.0%), ovarian follicular cysts (2.3%), gestational loss (1.5%), and hydrosalpinx (1.1%). This was the first study evaluating reproductive disorders in live animals that used a high number of Brazilian dairy goats. Considering that all these diseases affect fertility to different degrees, the performance of transrectal ultrasonography exams twice a year is strongly suggested, in order to guide precocious treatment or discard the animal as soon as possible, thus reducing economic losses in dairy goat farming.

Mathematical modeling of the female reproductive system: from oocyte to delivery.

PubMed

Clark, Alys R; Kruger, Jennifer A

2017-01-01

From ovulation to delivery, and through the menstrual cycle, the female reproductive system undergoes many dynamic changes to provide an optimal environment for the embryo to implant, and to develop successfully. It is difficult ethically and practically to observe the system over the timescales involved in growth and development (often hours to days). Even in carefully monitored conditions clinicians and biologists can only see snapshots of the development process. Mathematical models are emerging as a key means to supplement our knowledge of the reproductive process, and to tease apart complexity in the reproductive system. These models have been used successfully to test existing hypotheses regarding the mechanisms of female infertility and pathological fetal development, and also to provide new experimentally testable hypotheses regarding the process of development. This new knowledge has allowed for improvements in assisted reproductive technologies and is moving toward translation to clinical practice via multiscale assessments of the dynamics of ovulation, development in pregnancy, and the timing and mechanics of delivery. WIREs Syst Biol Med 2017, 9:e1353. doi: 10.1002/wsbm.1353 For further resources related to this article, please visit the WIREs website. © 2016 Wiley Periodicals, Inc.

Temperature stress and plant sexual reproduction: uncovering the weakest links.

PubMed

Zinn, Kelly E; Tunc-Ozdemir, Meral; Harper, Jeffrey F

2010-04-01

The reproductive (gametophytic) phase in flowering plants is often highly sensitive to hot or cold temperature stresses, with even a single hot day or cold night sometimes being fatal to reproductive success. This review describes studies of temperature stress on several crop plants, which suggest that pollen development and fertilization may often be the most sensitive reproductive stage. Transcriptome and proteomic studies on several plant species are beginning to identify stress response pathways that function during pollen development. An example is provided here of genotypic differences in the reproductive stress tolerance between two ecotypes of Arabidopsis thaliana Columbia (Col) and Hilversum (Hi-0), when reproducing under conditions of hot days and cold nights. Hi-0 exhibited a more severe reduction in seed set, correlated with a reduction in pollen tube growth potential and tropism defects. Hi-0 thus provides an Arabidopsis model to investigate strategies for improved stress tolerance in pollen. Understanding how different plants cope with stress during reproductive development offers the potential to identify genetic traits that could be manipulated to improve temperature tolerance in selected crop species being cultivated in marginal climates.

The role of early life nutrition in programming of reproductive function.

PubMed

Chadio, S; Kotsampasi, B

2014-02-01

Accumulating evidence suggest that the concept of programming can also be applied to reproductive development and function, representing an ever expanding research area. Recently issues such as peri- or even preconceptional nutrition, transgenerational effects and underlying mechanisms have received considerable attention. The present chapter presents the existed evidence and reviews the available data from numerous animal and human studies on the effects of early life nutritional environment on adult reproductive function. Specific outcomes depend on the severity, duration and stage of development when nutritional perturbations are imposed, while sex-specific effects are also manifested. Apart from undernutrition, effects of relative overnutrition as well as the complex interactions between pre- and postnatal nutrition is of high importance, especially in the context of our days obesity epidemic. Mechanisms underlying reproductive programming are yet unclear, but may include a role for epigenetic modifications. Epigenetic modulation of critical genes involved in the control of reproductive function and potential intergenerational effects represent an exciting area of interdisciplinary research toward the development of new nutritional approaches during pre- and postnatal periods to ensure reproductive health in later life.

Cow-calf reproductive, genetic, and nutritional management to improve the sustainability of whole beef production systems.

PubMed

White, R R; Brady, M; Capper, J L; McNamara, J P; Johnson, K A

2015-06-01

Optimizing efficiency in the cow-calf sector is an important step toward improving beef sustainability. The objective of the study was to use a model to identify the relative roles of reproductive, genetic, and nutritional management in minimizing beef production systems' environmental impact in an economically viable, socially acceptable manner. An economic and environmental diet optimizer was used to identify ideal nutritional management of beef production systems varying in genetic and reproductive technology use. Eight management scenarios were compared to a least cost baseline: average U.S. production practices (CON), CON with variable nutritional management (NUT), twinning cattle (TWN), early weaning (EW), sire selection by EPD using either on-farm bulls (EPD-B) or AI (EPD-AI), decreasing the calving window (CW), or selecting bulls by EPD and reducing the calving window (EPD-CW). Diets to minimize land use, water use, and/or greenhouse gas (GHG) emissions were optimized under each scenario. Increases in diet cost attributable to reducing environmental impact were constrained to less than stakeholder willingness to pay for improved efficiency and reduced environmental impact. Baseline land use, water use, and GHG emissions were 188 m, 712 L, and 21.9 kg/kg HCW beef. The NUT scenario, which assessed opportunities to improve sustainability by altering nutritional management alone, resulted in a simultaneous 1.5% reduction in land use, water use, and GHG emissions. The CW scenario improved calf uniformity and simultaneously decreased land use, water use, and GHG emissions by 3.2%. Twinning resulted in a 9.2% reduction in the 3 environmental impact metrics. The EW scenario allowed for an 8.5% reduction in the 3 metrics. The EPD-AI scenario resulted in an 11.1% reduction, which was comparable to the 11.3% reduction achieved by EPD-B in the 3 metrics. Improving genetic selection by using AI or by purchasing on-farm bulls based on their superior EPD demonstrated clear opportunity to improve sustainability. When genetic and reproductive technologies were adopted, up to a 12.4% reduction in environmental impact was achievable. Given the modeling assumptions used in this study, optimizing nutritional management while concurrently improving genetic and reproductive efficiency may be promising avenues to improve productivity and sustainability of U.S. beef systems.

Reproductive toxicity in boron exposed workers in Bandirma, Turkey.

PubMed

Başaran, Nurşen; Duydu, Yalçin; Bolt, Hermann M

2012-06-01

Boric acid and sodium borates have been considered as being "toxic to reproduction and development", following results of animal studies with high doses. However unfavorable effects of boron exposure on reproduction and development have not been proved in epidemiological studies so far. The aim of the present study was to investigate the reproductive toxicity indicators in highly exposed workers employed in a boric acid production plant in Bandırma, Turkey. Two hundred and four workers participated in this study. The mean blood boron concentration of the high exposure group of workers was 223.89 ± 69.49 (152.82-454.02)ng/g. Unfavorable effects of boron exposure on the reproductive toxicity indicators were not observed. Copyright © 2012 Elsevier GmbH. All rights reserved.

Weather, hydroregime, and breeding effort influence juvenile recruitment of anurans: implications for climate change

DOE PAGES

Greenberg, C. H.; Zarnoch, S. J.; Austin, J. D.

2017-05-03

Amphibians that primarily breed in ephemeral wetlands are especially vulnerable to climate change because they rely on rainfall or temperature to initiate breeding and create suitable hydroregimes (water duration, timing, frequency, depth) for reproductive success. Hydroregime effects on reproductive success are likely to differ among species because of differences in reproductive strategies: the length and timing of breeding period, rate of larval development, and timing of metamorphosis. We applied an information-theoretic approach to 22 consecutive years of continuous amphibian trapping data at eight ephemeral wetlands to test hypotheses regarding environmental (hydroregime, weather) and biological (adult breeding effort) factors affecting juvenilemore » recruitment (JR) by six focal species representing four reproductive strategies. We hypothesized that (1) JR by species with similar reproductive strategies would be influenced by similar variables; (2) JR would be higher for all species when models encompassed the maximum time span of potential tadpole occurrence and development; and (3) JR rates within individual wetlands and breeding cycles would correlate most closely between species with similar breeding strategies. The best model for all focal species (except Scaphiopus holbrookii) encompassed the maximum time span and indicated that ≥1 hydroregime variable, total precipitation, or both were important drivers of reproductive success; average air temperature was not. Continuous hydroperiod through peak juvenile emigration was an important predictor of JR for species with prolonged breeding periods, slow larval development, and a “fixed” late spring start date for juvenile emigration (regardless of when oviposition occurred, or cohort age; Lithobates capito, Lithobates sphenocephalus), but not for species with rapid larval development and continual emigration as cohorts complete metamorphosis ( Anaxyrus terrestris, Anaxyrus quercicus, Gastrophryne carolinensis, S. holbrookii). Total rainfall was positively associated with recruitment for most species; depth characteristics affected species differently. Annual JR was positively correlated among species with similar reproductive strategies. Our results indicate that weather and hydroregime characteristics interact with reproductive strategies that differ among amphibian species and influence reproductive plasticity, opportunity, and success. In conclusion, effects of altered weather patterns associated with climate change on amphibian reproductive success may correspond more closely among species having similar reproductive strategies, with critical implications for population trends and assemblages.« less

Weather, hydroregime, and breeding effort influence juvenile recruitment of anurans: implications for climate change

DOE Office of Scientific and Technical Information (OSTI.GOV)

Greenberg, C. H.; Zarnoch, S. J.; Austin, J. D.

Amphibians that primarily breed in ephemeral wetlands are especially vulnerable to climate change because they rely on rainfall or temperature to initiate breeding and create suitable hydroregimes (water duration, timing, frequency, depth) for reproductive success. Hydroregime effects on reproductive success are likely to differ among species because of differences in reproductive strategies: the length and timing of breeding period, rate of larval development, and timing of metamorphosis. We applied an information-theoretic approach to 22 consecutive years of continuous amphibian trapping data at eight ephemeral wetlands to test hypotheses regarding environmental (hydroregime, weather) and biological (adult breeding effort) factors affecting juvenilemore » recruitment (JR) by six focal species representing four reproductive strategies. We hypothesized that (1) JR by species with similar reproductive strategies would be influenced by similar variables; (2) JR would be higher for all species when models encompassed the maximum time span of potential tadpole occurrence and development; and (3) JR rates within individual wetlands and breeding cycles would correlate most closely between species with similar breeding strategies. The best model for all focal species (except Scaphiopus holbrookii) encompassed the maximum time span and indicated that ≥1 hydroregime variable, total precipitation, or both were important drivers of reproductive success; average air temperature was not. Continuous hydroperiod through peak juvenile emigration was an important predictor of JR for species with prolonged breeding periods, slow larval development, and a “fixed” late spring start date for juvenile emigration (regardless of when oviposition occurred, or cohort age; Lithobates capito, Lithobates sphenocephalus), but not for species with rapid larval development and continual emigration as cohorts complete metamorphosis ( Anaxyrus terrestris, Anaxyrus quercicus, Gastrophryne carolinensis, S. holbrookii). Total rainfall was positively associated with recruitment for most species; depth characteristics affected species differently. Annual JR was positively correlated among species with similar reproductive strategies. Our results indicate that weather and hydroregime characteristics interact with reproductive strategies that differ among amphibian species and influence reproductive plasticity, opportunity, and success. In conclusion, effects of altered weather patterns associated with climate change on amphibian reproductive success may correspond more closely among species having similar reproductive strategies, with critical implications for population trends and assemblages.« less

The special programme of research in human reproduction: forty years of activities to achieve reproductive health for all.

PubMed

Benagiano, Giuseppe; d'Arcangues, Catherine; Harris Requejo, Jennifer; Schafer, Alessandra; Say, Lale; Merialdi, Mario

2012-01-01

The Special Programme of Research in Human Reproduction (HRP), co-sponsored by the UNDP, UNFPA, WHO, and the World Bank, is celebrating 40 years of activities with an expansion of its mandate and new co-sponsors. When it began, in 1972, the main focus was on evaluating the acceptability, effectiveness, and safety of existing fertility-regulating methods, as well as developing new, improved modalities for family planning. In 1994, HRP not only made major contributions to the Plan of Action of the International Conference on Population and Development (ICPD); it also broadened its scope of work to include other aspects of health dealing with sexuality and reproduction, adding a specific perspective on gender issues and human rights. In 2002, HRP's mandate was once again broadened to include sexually transmitted infections and HIV/AIDS and in 2003 it was further expanded to research activities on preventing violence against women and its many dire health consequences. Today, the work of the Programme includes research on: the sexual and reproductive health of adolescents, women, and men; maternal and perinatal health; reproductive tract and sexually transmitted infections (including HIV/AIDS); family planning; infertility; unsafe abortion; sexual health; screening for cancer of the cervix in developing countries, and gender and reproductive rights. Additional activities by the Programme have included: fostering international cooperation in the field of human reproduction; the elaboration of WHO's first Global Reproductive Health Strategy; work leading to the inclusion of ICPD's goal 'reproductive health for all by 2015' into the Millennium Development Goal framework; the promotion of critical interagency statements on the public health, legal, and human rights implications of female genital mutilation and gender-biased sex selection. Finally, HRP has been involved in the creation of guidelines and tools, such as the 'Medical eligibility criteria for contraceptive use', the 'Global handbook for family planning providers', the 'Definition of core competencies in primary health care', and designing tools for operationalizing a human rights approach to sexual and reproductive health programmes. Copyright © 2012 S. Karger AG, Basel.

[Nuclear transfer and therapeutic cloning].

PubMed

Xu, Xiao-Ming; Lei, An-Min; Hua, Jin-Lian; Dou, Zhong-Ying

2005-03-01

Nuclear transfer and therapeutic cloning have widespread and attractive prospects in animal agriculture and biomedical applications. We reviewed that the quality of oocytes and nuclear reprogramming of somatic donor cells were the main reasons of the common abnormalities in cloned animals and the low efficiency of cloning and showed the problems and outlets in therapeutic cloning, such as some basic problems in nuclear transfer affected clinical applications of therapeutic cloning. Study on isolation and culture of nuclear transfer embryonic stem (ntES) cells and specific differentiation of ntES cells into important functional cells should be emphasized and could enhance the efficiency. Adult stem cells could help to cure some great diseases, but could not replace therapeutic cloning. Ethics also impeded the development of therapeutic cloning. It is necessary to improve many techniques and reinforce the research of some basic theories, then somatic nuclear transfer and therapeutic cloning may apply to agriculture reproduction and benefit to human life better.

Evolutionary branching under multi-dimensional evolutionary constraints.

PubMed

Ito, Hiroshi; Sasaki, Akira

2016-10-21

The fitness of an existing phenotype and of a potential mutant should generally depend on the frequencies of other existing phenotypes. Adaptive evolution driven by such frequency-dependent fitness functions can be analyzed effectively using adaptive dynamics theory, assuming rare mutation and asexual reproduction. When possible mutations are restricted to certain directions due to developmental, physiological, or physical constraints, the resulting adaptive evolution may be restricted to subspaces (constraint surfaces) with fewer dimensionalities than the original trait spaces. To analyze such dynamics along constraint surfaces efficiently, we develop a Lagrange multiplier method in the framework of adaptive dynamics theory. On constraint surfaces of arbitrary dimensionalities described with equality constraints, our method efficiently finds local evolutionarily stable strategies, convergence stable points, and evolutionary branching points. We also derive the conditions for the existence of evolutionary branching points on constraint surfaces when the shapes of the surfaces can be chosen freely. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fertility in South Australian commercial Merino flocks: aspects of management.

PubMed

Kleemann, David O; Grosser, Timothy I; Walker, Simon K

2006-05-01

Wide variation in reproductive performance of commercial Merino flocks in south central Australia is the result of genetic and environmental influences that are both amenable to change through decisions of management. Relationships of reproductive traits (estrus, ovulation, fertility, fecundity, lamb survival, and lambs weaned) with variables that graziers can change or modify (strain of Merino, day or month of exposure of ewes to rams, ram effect or teasing, length of the mating period, ram percentage, days between weaning and next mating, stocking density and flock size at lambing, ewe liveweight, and condition) are reported in this paper, the third in a series. Small differences were observed between medium and strong-wool South Australian Merino strains for reproductive traits. Choosing the time of year that ewes are exposed to rams, between late spring to autumn, may result in reduced ovulation rate during early summer (December) giving a potentially smaller net reproductive efficiency (lambs weaned). The ram effect or teasing, used by about 50% of graziers to synchronise lambing, could be effectively employed to the end of January. The technique was not reproductively advantageous when compared with flocks that were not teased. The percentage of rams mated to ewes varied widely (approximately 1-3%) and did not alter flock fertility, suggesting that a substantial proportion of graziers could safely reduce the number of rams purchased. A positive relationship between incidence of estrus during the first 14 d of the cycle and the number of days from weaning to next mating and a negative relationship of returns to service with the same variable indicates that managers should consider increasing the time allowed for recovery of liveweight and body condition by adjusting age at weaning, length of the mating period, or both. Lamb survival was curvilinearly related to flock size and not stocking intensity, with the optimum size at about 400 ewes. The number of lambs weaned per 100 ewes exposed to rams increased by 1.0 kg(-1) increase in liveweight at mating. We concluded that the major factor controlling net reproductive efficiency is nutritional in origin through its effects on ewe liveweight and condition, and is a factor that can be largely manipulated through management.

Evaluation of the impact of the voucher and accreditation approach on improving reproductive behaviors and RH status: Bangladesh

PubMed Central

2011-01-01

Background Cost of delivering reproductive health services to low-income populations will always require total or partial subsidization by the government and/or development partners. Broadly termed "Demand-Side Financing" or "Output-Based Aid", includes a range of interventions that channel government or donor subsidies to the service user rather than the service provider. Initial findings from the few assessments of reproductive health voucher-and-accreditation programs suggest that, if implemented well, these programs have great potential for achieving the policy objectives of increasing access and use, reducing inequities and enhancing program efficiency and service quality. At this point in time, however, there is a paucity of evidence describing how the various voucher programs function in different settings, for various reproductive health services. Methods/Design Population Council-Nairobi, funded by the Bill and Melinda Gates Foundation, intends to address the lack of evidence around the pros and cons of 'voucher and accreditation' approaches to improving the reproductive health of low income women in five developing countries. In Bangladesh, the activities will be conducted in 11 accredited health facilities where Demand Side Financing program is being implemented and compared with populations drawn from areas served by similar non-accredited facilities. Facility inventories, client exit interviews and service provider interviews will be used to collect comparable data across each facility for assessing readiness and quality of care. In-depth interviews with key stakeholders will be conducted to gain a deeper understanding about the program. A population-based survey will also be carried out in two types of locations: areas where vouchers are distributed and similar locations where vouchers are not distributed. Discussion This is a quasi-experimental study which will investigate the impact of the voucher approach on improving maternal health behaviors and status and reducing inequities at the population level. We expect a significant increase in the utilization of maternal health care services by the accredited health facilities in the experimental areas compared to the control areas as a direct result of the interventions. If the voucher scheme in Bangladesh is found effective, it may help other countries to adopt this approach for improving utilization of maternity care services for reducing maternal mortality. PMID:21513528

Evaluation of the impact of the voucher and accreditation approach on improving reproductive behaviors and RH status: Bangladesh.

PubMed

Rob, Ubaidur; Rahman, Moshiur; Bellows, Benjamin

2011-04-22

Cost of delivering reproductive health services to low-income populations will always require total or partial subsidization by the government and/or development partners. Broadly termed "Demand-Side Financing" or "Output-Based Aid", includes a range of interventions that channel government or donor subsidies to the service user rather than the service provider. Initial findings from the few assessments of reproductive health voucher-and-accreditation programs suggest that, if implemented well, these programs have great potential for achieving the policy objectives of increasing access and use, reducing inequities and enhancing program efficiency and service quality. At this point in time, however, there is a paucity of evidence describing how the various voucher programs function in different settings, for various reproductive health services. Population Council-Nairobi, funded by the Bill and Melinda Gates Foundation, intends to address the lack of evidence around the pros and cons of 'voucher and accreditation' approaches to improving the reproductive health of low income women in five developing countries. In Bangladesh, the activities will be conducted in 11 accredited health facilities where Demand Side Financing program is being implemented and compared with populations drawn from areas served by similar non-accredited facilities. Facility inventories, client exit interviews and service provider interviews will be used to collect comparable data across each facility for assessing readiness and quality of care. In-depth interviews with key stakeholders will be conducted to gain a deeper understanding about the program. A population-based survey will also be carried out in two types of locations: areas where vouchers are distributed and similar locations where vouchers are not distributed. This is a quasi-experimental study which will investigate the impact of the voucher approach on improving maternal health behaviors and status and reducing inequities at the population level. We expect a significant increase in the utilization of maternal health care services by the accredited health facilities in the experimental areas compared to the control areas as a direct result of the interventions. If the voucher scheme in Bangladesh is found effective, it may help other countries to adopt this approach for improving utilization of maternity care services for reducing maternal mortality.

Within-litter variation in birth weight: impact of nutritional status in the sow.

PubMed

Yuan, Tao-lin; Zhu, Yu-hua; Shi, Meng; Li, Tian-tian; Li, Na; Wu, Guo-yao; Bazer, Fuller W; Zang, Jian-jun; Wang, Feng-lai; Wang, Jun-jun

2015-06-01

Accompanying the beneficial improvement in litter size from genetic selection for high-prolificacy sows, within-litter variation in birth weight has increased with detrimental effects on post-natal growth and survival due to an increase in the proportion of piglets with low birth-weight. Causes of within-litter variation in birth weight include breed characteristics that affect uterine space, ovulation rate, degree of maturation of oocytes, duration of time required for ovulation, interval between ovulation and fertilization, uterine capacity for implantation and placentation, size and efficiency of placental transport of nutrients, communication between conceptus/fetus and maternal systems, as well as nutritional status and environmental influences during gestation. Because these factors contribute to within-litter variation in birth weight, nutritional status of the sow to improve fetal-placental development must focus on the following three important stages in the reproductive cycle: pre-mating or weaning to estrus, early gestation and late gestation. The goal is to increase the homogeneity of development of oocytes and conceptuses, decrease variations in conceptus development during implantation and placentation, and improve birth weights of newborn piglets. Though some progress has been made in nutritional regulation of within-litter variation in the birth weight of piglets, additional studies, with a focus on and insights into molecular mechanisms of reproductive physiology from the aspects of maternal growth and offspring development, as well as their regulation by nutrients provided to the sow, are urgently needed.

Determinants of maternal health care services utilization in Pakistan: evidence from Pakistan demographic and health survey, 2012-13.

PubMed

Zakar, Rubeena; Zakar, Muhammad Zakria; Aqil, Nauman; Chaudhry, Ashraf; Nasrullah, Muazzam

2017-04-01

The aim of this study was to determine the association between maternal utilisation of health-care services and socio-demographic factors among reproductive-age women in Pakistan. We used the sample of ever-married reproductive-age women (n = 7446) from the Pakistan Demographic and Health Survey (PDHS), 2012-13. We measured maternal utilisation of health-care services by using three dependent variables: number of antenatal care (ANC) visits, delivery assistance by a skilled health provider, and delivery in a health-care facility. Around 36.6% of women had made four or more ANC visits, 59% had received assistance from skilled health providers during delivery, and 55.3% had given birth in a health-care facility. On multivariable logistic regression, all three variables were positively associated with education and wealth, and negatively associated with birth order and women's autonomy. Policymakers and health planners may use our findings to develop efficient strategies, particularly for uneducated women and those with poor economic status, to improve the utilisation of maternal health-care services in Pakistan.

Effects of gamma irradiation on different stages of mealybug Dysmicoccus neobrevipes (Hemiptera: Pseudococcidae)

NASA Astrophysics Data System (ADS)

The, Doan Thi; Khanh, Nguyen Thuy; Lang, Vo Thi Kim; Van Chung, Cao; An, Tran Thi Thien; Thi, Nguyen Hoang Hanh

2012-01-01

Utilization of phytosanitary irradiation as a potential treatment to disinfest agricultural commodities in trade has expanded rapidly in the recent years. Cobalt-60 gamma ray target doses of 100, 150, 200 and 250 Gy were used to irradiate immatures and adults of Dysmicoccus neobrevipes (Beardsley) (Hemiptera: Pseudococcidae) infesting dragon fruits to find the most tolerant stage and the most optimal dose range for quarantine treatment. In general, irradiation affected significantly all life stages of D. neobrevipes mortality and adult reproduction. The pattern of tolerance to irradiation in D. neobrevipes was 1st instars<2nd instars<3rd instars

Juvenile hormone, but not nutrition or social cues, affects reproductive maturation in solitary alkali bees (Nomia melanderi).

PubMed

Kapheim, Karen M; Johnson, Makenna M

2017-10-15

Eusocial insect colonies are defined by extreme variation in reproductive activity among castes, but the ancestral conditions from which this variation arose are unknown. Investigating the factors that contribute to variation in reproductive physiology among solitary insects that are closely related to social species can help to fill this gap. We experimentally tested the role of nutrition, juvenile hormone (JH) and social cues on reproductive maturation in solitary alkali bees (Halictidae: Nomia melanderi ). We found that alkali bee females emerge from overwintering with small Dufour's glands and small ovaries, containing oocytes in the early stages of development. Oocyte maturation occurs rapidly, and is staggered between the two ovaries. Lab-reared females reached reproductive maturity without access to mates or nesting opportunities, and many had resorbed oocytes. Initial activation of these reproductive structures does not depend on pollen consumption, though dietary protein or lipids may be necessary for long-term reproductive activity. JH is likely to be a limiting factor in alkali bee reproductive activation, as females treated with JH were more likely to develop mature oocytes and Dufour's glands. Unlike for related social bees, the effects of JH were not suppressed by the presence of older, reproductive females. These results provide valuable insight into the factors that influence reproductive activity in an important native pollinator, and those that may have been particularly influential in the evolution of reproductive castes. © 2017. Published by The Company of Biologists Ltd.

Effects of ozonated sewage effluent on reproduction and behavioral endpoints in zebrafish (Danio rerio).

PubMed

Pohl, Johannes; Björlenius, Berndt; Brodin, Tomas; Carlsson, Gunnar; Fick, Jerker; Larsson, D G Joakim; Norrgren, Leif; Örn, Stefan

2018-04-25

Pharmaceutical residues and other micro-contaminants may enter aquatic environments through effluent from sewage treatment plants (STPs) and could cause adverse effects in wild fish. One strategy to alleviate this situation is to improve wastewater treatment by ozonation. To test the effectiveness of full-scale wastewater effluent ozonation at a Swedish municipal STP, the added removal efficiency was measured for 105 pharmaceuticals. In addition, gene expression, reproductive and behavioral endpoints were analyzed in zebrafish (Danio rerio) exposed on-site over 21 days to ozonated or non-ozonated effluents as well as to tap water. Ozone treatment (7 g O 3 /m 3 ) removed pharmaceuticals by an average efficiency of 77% in addition to the conventional treatment, leaving 11 screened pharmaceuticals above detection limits. Differences in biological responses of the exposure treatments were recorded in gene expression, reproduction and behavior. Hepatic vitellogenin gene expression was higher in male zebrafish exposed to the ozonated effluent compared to the non-ozonated effluent and tap water treatments. The reproductive success was higher in fish exposed to ozonated effluent compared to non-ozonated effluent and to tap water. The behavioral measurements showed that fish exposed to the ozonated STP effluent were less active in swimming the first minute after placed in a novel vessel. Ozonation is a capable method for removing pharmaceuticals in effluents. However, its implementation should be thoroughly evaluated for any potential biological impact. Future research is needed for uncovering the factors which produced the in vivo responses in fish. Copyright © 2018 Elsevier B.V. All rights reserved.

Comprehensive evaluation of contemporary assisted reproduction technology laboratory operations to determine staffing levels that promote patient safety and quality care.

PubMed

Alikani, Mina; Go, Kathryn J; McCaffrey, Caroline; McCulloh, David H

2014-11-01

To consider how staffing requirements have changed with evolving and increasingly more complex assisted reproduction technology (ART) laboratory practice. Analysis by four laboratory directors from three different ART programs of the level of complexity and time requirements for contemporary ART laboratory activities to determine adequate staffing levels. University-based and private ART programs. None. None. Human resource requirements for ART procedures. Both complexity and time required for completion of a contemporary ART cycle have increased significantly compared with the same requirements for the "traditional cycle" of the past. The latter required roughly 9 personnel hours, but a contemporary cycle can require up to 20 hours for completion. Consistent with this increase, a quantitative analysis shows that the number of embryologists required for safe and efficient operation of the ART laboratory has also increased. This number depends on not only the volume but also the types of procedures performed: the higher the number of complex procedures, the more personnel required. An interactive Personnel Calculator is introduced that can help determine staffing needs. The increased complexity of the contemporary ART laboratory requires a new look at the allocation of human resources. Our work provides laboratory directors with a practical, individualized tool to determine their staffing requirements with a view to increasing the safety and efficiency of operations. The work could serve as the basis for revision of the 2008 American Society for Reproductive Medicine (ASRM) staffing guidelines. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Impact of reproductive technologies on dairy food production in the dairy industry.

PubMed

Stevenson, Jeffrey S

2014-01-01

Reproductive technologies drive the efficiency of managing dairy cows because the lactation cycle of the dairy cow depends on regular calving to renew lactation yields. Achieving timely pregnancies to allow calving every 12-14 months, therefore, is critical in modern dairy production. To meet the demands to produce sufficient milk for fluid and dairy products, various technologies are applied to enhance efficiencies on the dairy farm. Artificial insemination (AI), embryo transfer, ultrasonographic and chemical detection of pregnancy, various monitors that detect or predict estrus, and handheld communication and testing devices allow managers to retrieve information to make cow-side decisions about health and reproductive status. Genomic testing of young potential sires or young heifers is now possible and can provide information about their genetic merit years before any progeny tests can be completed. In many countries, the challenge faced by dairy producers is their ability to afford these technologies in the face of rising feed and labor costs and volatile milk prices received at the farm gate. Government policies often place obstacles, trade barriers, and unfunded mandates that preclude operations from making a modest profit. Unlike nearly all other manufacturing industries, agriculture producers have little control over the price received for their products. Therefore, dairy production is vulnerable to many uncontrolled factors including climate, government policy, economic conditions, and skilled labor shortages. It is clear that the impact of emerging and current reproductive technologies is critical to the management of dairy cattle to produce sufficient milk to meet consumer demands for quality fluid and dairy products.

The evolution of reproductive diversity in Afrobatrachia: A phylogenetic comparative analysis of an extensive radiation of African frogs.

PubMed

Portik, Daniel M; Blackburn, David C

2016-09-01

The reproductive modes of anurans (frogs and toads) are the most diverse of terrestrial vertebrates, and a major challenge is identifying selective factors that promote the evolution or retention of reproductive modes across clades. Terrestrialized anuran breeding strategies have evolved repeatedly from the plesiomorphic fully aquatic reproductive mode, a process thought to occur through intermediate reproductive stages. Several selective forces have been proposed for the evolution of terrestrialized reproductive traits, but factors such as water systems and co-evolution with ecomorphologies have not been investigated. We examined these topics in a comparative phylogenetic framework using Afrobatrachian frogs, an ecologically and reproductively diverse clade representing more than half of the total frog diversity found in Africa (∼400 species). We infer direct development has evolved twice independently from terrestrialized reproductive modes involving subterranean or terrestrial oviposition, supporting evolution through intermediate stages. We also detect associations between specific ecomorphologies and oviposition sites, and demonstrate arboreal species exhibit an overall shift toward using lentic water systems for breeding. These results indicate that changes in microhabitat use associated with ecomorphology, which allow access to novel sites for reproductive behavior, oviposition, or larval development, may also promote reproductive mode diversity in anurans. © 2016 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

[Benefit of network education to college students' knowledge about sexual and reproductive health in Ningbo city].

PubMed

Wang, Guo-yao; Ji, Yun-xin; Ding, Hui-qing; Gui, Zhong-bao; Liang, Xiao-ming; Fu, Jian-fei; Cheng, Yue

2015-12-01

To investigate how network education can improve college students' knowledge on sexual and reproductive health in Ningbo city. From December 2012 to June 2013, we conducted a questionnaire investigation among college students in Ningbo city about the effects of network education on their knowledge about sexual psychology, sexual physiology, sexual ethics, and reproductive health. A total of 7 362 college students accomplished the investigation, of whom 2 483 (42.1% males and 57.9% females) received network education, while the other 4 879 (24.1% males and 75.9% females) did not. Approximately 47.1% of the male and 28.0% of the female students acquired sexual and reproductive knowledge via network education. Reproductive health-related network education significantly enriched the students' knowledge about the reproductive system and sex, pubertal development, sexual physiology, conception and embryonic development, methods of contraception, sexual psychology, sexually transmitted diseases and their prevention, pregnancy care and eugenics, and environment- and occupation-related reproductive health (P < 0.01). It also remarkably improved their cognitive attitude towards reproductive health knowledge (P < 0.01). Those who received reproductive health-related network education showed a significantly higher rate of masturbation (P < 0.01) but markedly later time of the first masturbation (P < 0.01) than those who did not. Network education can enhance the effect of reproductive health education among college students and improve their sexual experience and health.

Phenology of sexual reproduction in the common coral reef sponge, Carteriospongia foliascens

NASA Astrophysics Data System (ADS)

Abdul Wahab, M. A.; de Nys, R.; Webster, N.; Whalan, S.

2014-06-01

Understanding processes that contribute to population maintenance is critical to the management and conservation of species. Despite this, very little is currently known about the reproductive biology of Great Barrier Reef (GBR) sponge species. Here, we established reproductive parameters including mode of sexuality and development, seasonality, sex ratios, gametogenesis, reproductive output, and size at sexual maturity for the common phototrophic intertidal sponge, Carteriospongia foliascens, in the central GBR over two reproductive cycles. A population sexual productivity index (PoSPi) integrating key reproductive parameters was formulated to compare population larval supply over time. This study shows that C. foliascens is reproductive all year round, gonochoric and viviparous, with larvae developing asynchronously throughout the mesohyl. The influence of environmental parameters relevant to C. foliascens reproduction [i.e., sea surface temperature (SST), photoperiod, and rainfall] was also examined, and SST was found to have the most significant effect on phenology. C. foliascens reproduction exhibited annual mono-cyclic patterns closely resembling SST fluctuations. Reproductive output was depressed at low SST (<23 °C) and increased at temperatures above 23 °C. Peak sperm release occurred at temperatures above 25 °C, while peak larval release occurred during the annual temperature maxima (>28 °C). A twofold increase in maximum larval production (PoSPi) in C. foliascens was observed in the second reproductive cycle, following a depressed PoSPi in the first cycle. This reduction in PoSPi in the first reproductive cycle was associated with elevated SST and rainfall, coinciding with one of the strongest La Niña events on record.

"Will my work affect my pregnancy?" Resources for anticipating and answering patients' questions.

PubMed

Grajewski, Barbara; Rocheleau, Carissa M; Lawson, Christina C; Johnson, Candice Y

2016-05-01

Authoritative information on occupational reproductive hazards is scarce and complex because exposure levels vary, multiple exposures may be present, and the reproductive toxicity of many agents remains unknown. For these reasons, women's health providers may find it challenging to effectively address workplace reproductive health issues with their patients who are pregnant, breast-feeding, or considering pregnancy. Reproductive epidemiologists at the Centers for Disease Control and Prevention National Institute for Occupational Safety and Health answered >200 public requests for occupational reproductive health information during 2009 through 2013. The most frequent occupations represented were health care (41%) and laboratory work (18%). The most common requests for exposure information concerned solvents (14%), anesthetic gases (10%), formaldehyde (7%), infectious agents in laboratories (7%) or health care settings (7%), and physical agents (14%), including ionizing radiation (6%). Information for developing workplace policies or guidelines was sought by 12% of the requestors. Occupational exposure effects on breast-feeding were an increasing concern among working women. Based on information developed in response to these requestors, information is provided for discussing workplace exposures with patients, assessing potential workplace reproductive hazards, and helping patients determine the best options for safe work in pregnancy. Appendices provide resources to address specific occupational exposures, employee groups, personal protective equipment, breast-feeding, and workplace regulations regarding work and pregnancy. These tools can help identify those most at risk of occupational reproductive hazards and improve workers' reproductive health. The information can also be used to inform research priorities and assist the development of workplace reproductive health policies. Published by Elsevier Inc.

Changes in sex steroid hormone levels reflect the reproductive status of captive female zebra sharks (Stegostoma fasciatum).

PubMed

Nozu, Ryo; Murakumo, Kiyomi; Yano, Nagisa; Furuyama, Rina; Matsumoto, Rui; Yanagisawa, Makio; Sato, Keiichi

2018-03-03

Captive breeding in aquaria is a useful means for ex situ preservation of threatened elasmobranch species. To promote captive breeding, it is important to determine the female reproductive status. However, information regarding reproductive status in female elasmobranchs is limited. Here, we used zebra sharks, Stegostoma fasciatum, as a model for elasmobranch reproduction in captivity. We investigated the relationships among changes in the sex steroid hormone levels, follicle size, and egg-laying period to develop indicators for the female reproductive status. We confirmed that mature female zebra sharks undergo an annual reproductive cycle. Additionally, we showed that the variations in sex steroid hormone levels correlated with reproductive status in mature female zebra sharks. Plasma estradiol-17ß (E2) concentrations increased two months before ovarian follicle development and decreased along with follicle regression. Interestingly, E2 levels were inversely correlated with water temperature (R = -0.901). Moreover, high levels of testosterone (T) correlated well with the laying period. These results strongly suggest that E2 is an indicator for ovarian follicle development, and that T is a useful indicator for both the onset and end of the egg-laying period in captive zebra sharks. Copyright © 2018 Elsevier Inc. All rights reserved.

The influence of control group reproduction on the statistical ...

EPA Pesticide Factsheets

Because of various Congressional mandates to protect the environment from endocrine disrupting chemicals (EDCs), the United States Environmental Protection Agency (USEPA) initiated the Endocrine Disruptor Screening Program. In the context of this framework, the Office of Research and Development within the USEPA developed the Medaka Extended One Generation Reproduction Test (MEOGRT) to characterize the endocrine action of a suspected EDC. One important endpoint of the MEOGRT is fecundity of breeding pairs of medaka. Power analyses were conducted to determine the number of replicates needed in proposed test designs and to determine the effects that varying reproductive parameters (e.g. mean fecundity, variance, and days with no egg production) will have on the statistical power of the test. A software tool, the MEOGRT Reproduction Power Analysis Tool, was developed to expedite these power analyses by both calculating estimates of the needed reproductive parameters (e.g. population mean and variance) and performing the power analysis under user specified scenarios. The manuscript illustrates how the reproductive performance of the control medaka that are used in a MEOGRT influence statistical power, and therefore the successful implementation of the protocol. Example scenarios, based upon medaka reproduction data collected at MED, are discussed that bolster the recommendation that facilities planning to implement the MEOGRT should have a culture of medaka with hi

Proceedings of the Summit on Environmental Challenges to Reproductive Health and Fertility: Executive Summary

PubMed Central

Woodruff, Tracey J.; Carlson, Alison; Schwartz, Jackie M.; Giudice, Linda C.

2008-01-01

The 2007 Summit on “Environmental Challenges to Reproductive Health and Fertility” convened scientists, health care professionals, community groups, political representatives and the media to hear presentations on the impact of environmental contaminants on reproductive health and fertility and to discuss opportunities to improve health through research, education, communication and policy. Environmental reproductive health focuses on exposures to environmental contaminants, particularly during critical periods of development, and their potential effects on future reproductive health, including conception, fertility, pregnancy, adolescent development and adult health. Approximately 87,000 chemical substances are registered for use in commerce in the US, with ubiquitous human exposures to environmental contaminants in air, water, food and consumer products. Exposures during critical windows of susceptibility may result in adverse effects with lifelong and even intergenerational health impacts. Effects can include impaired development and function of the reproductive tract and permanently altered gene expression, leading to metabolic and hormonal disorders, reduced fertility and fecundity and illnesses such as testicular, prostate, uterine and cervical cancers later in life. This executive summary reviews effects of pre- and post-natal exposures on male and female reproductive health and provides a series of recommendations for advancing the field in the areas of research, policy, health care and community action. PMID:18275883

Efficient production of cynomolgus monkeys with a toolbox of enhanced assisted reproductive technologies

PubMed Central

Ma, Yunhan; Li, Jiayu; Wang, Ge; Ke, Qiong; Qiu, Sien; Gao, Liang; Wan, Haifeng; Zhou, Yang; Xiang, Andy Peng; Huang, Qunshan; Feng, Guoping; Zhou, Qi; Yang, Shihua

2016-01-01

The efficiency of assisted reproductive technologies (ARTs) in nonhuman primates is low due to no screening criterions for selecting sperm, oocyte, and embryo as well as its surrogate mothers. Here we analyzed 15 pairs of pregnant and non-pregnant cynomolgus monkeys, each pair of which received embryos from one batch of fertilized oocytes, and found ratio of endometrial to myometrial thicknesses in abdominal ultrasonic transverse section of uterus is a reliable indicator for selection of recipients for embryo transfer. We performed 305 ovarian stimulations in 128 female cynomolgus monkeys and found that ovarian stimulation can be performed in a whole year and repeated up to six times in the same monkey without deteriorating fertilization potential of eggs until a poor response to stimulation happened. Fertilization can be efficiently achieved with both conventional and piezo-driven intracytoplasmic sperm injection procedures. In semen collection, semen quality is higher with the penile robe electrical stimulus method compared with the rectal probe method. Moreover, caesarean section is an effective strategy for increasing baby survival rates of multiple pregnancies. These findings provide a practical guidance for the efficient use of ARTs, facilitating their use in genetic engineering of macaque monkeys for basic and translational neuroscience research. PMID:27173128

Nest establishment, pollination efficiency, and reproductive success of Megachile rotundata (Hymenoptera: Megachilidae) in relation to resource availability in field enclosures.

PubMed

Pitts-Singer, Theresa L; Bosch, Jordi

2010-02-01

The alfalfa leafcutting bee, Megachile rotundata (Fabricius), is used to pollinate alfalfa, Medicago sativa L., for seed production in the United States and Canada. It is difficult to reliably sustain commercial M. rotundata populations in the United States because of problems with disease, parasites, predators, and unexplained mortality. One possible explanation for early immature mortality is that, relative to floral availability, superfluous numbers of bees are released in alfalfa fields where resources quickly become limited. Our objective was to determine how M. rotundata density affects bee nesting, pollination efficiency, and reproductive success. Various numbers of bees were released into enclosures on an alfalfa field, but only 10-90% of released female bees established nests. Therefore, a "bee density index" was derived for each enclosure from the number of established females and number of open flowers over time. As the density index increased, significant reductions occurred in the number of pollinated flowers, number of nests, and number of cells produced per bee, as well as the percentage of cells that produced viable prepupae by summer's end and the percentage that produced adult bees. The percentage of cells resulting in early brood mortality (i.e., pollen balls) significantly increased as the density index increased. We conclude that bee nest establishment, pollination efficiency, and reproductive success are compromised when bee densities are high relative to floral resource availability. Open field studies are needed to determine commercial bee densities that result in sustainable bee populations and adequate pollination for profitable alfalfa seed production.

Effects of free-air CO2 and temperature enrichment on soybean growth and development

NASA Astrophysics Data System (ADS)

Ruiz Vera, U. M.; Bernacchi, C. J.

2012-12-01

According to the growing degree days approach, the progression of plant developmental stages requires certain accumulation of heat; therefore greenhouse gas-induced warming of the atmosphere could contribute to more rapid plant development. However, the influence of rising carbon dioxide concentration ([CO2]) on development of crops is uncertain, accelerating and other times delaying certain developmental stages. In soybean, the increase of [CO2] is shown to delay reproductive development, which is attributed to a higher investment of resources into extra nodes. The combined effects of elevated temperature and [CO2] can have significant changes in the progression through development that can influence on total grain production, carbon uptake, and susceptibility to early end-of-season frosts. We designed the Temperature by Free Air CO2 Enrichment (T-FACE) experiment to test over two growing seasons (2009 and 2011) and under field conditions the impact of increased temperature and/or [CO2] on soybean. The heated T-FACE subplots were situated in the larger FACE plots at 385 or 585 ppm of [CO2] and subjected to either ambient or heated (+~3.5°C) temperatures. The experiment is full factorial with ambient temperature and [CO2] (control), elevated temperature (eT), elevated [CO2] (eC) and combined (eT+eC) treatments. We hypothesized that soybean grown (1) under elevated [CO2] will produce more nodes than control, (2) under high temperature will produce nodes faster than control and (3) under both elevated temperature and [CO2] will produce more nodes in less time than control. For reproductive development, we hypothesized that (1) reproductive development will initiate simultaneously regardless of increased [CO2] or temperature because soybean reproduction is triggered by day length, (2) elevated temperature will accelerate the progression through key reproductive stages and (3) the delay in soybean reproductive development by elevated [CO2] will be ameliorated by the raise in temperature. Soybean developmental stages were recorded on six plants per subplot three times per week from emergence to senescence. In 2009, no temperature effect was detected on the vegetative development, but in 2011 temperature accelerates node formation. Elevated [CO2] was not significant on vegetative development, however plants under this effect produced more nodes than control. Reproductive development was delayed by elevated [CO2]. High temperature accelerated reproductive stages only in 2009, ameliorating the effect of elevated [CO2] in eT+eC. In 2011 elevated temperature delayed reproductive stages, a response that could be related with stress imposed by the weather conditions of that season. In the Midwest, the soybean cultivars generally mature before the first frost of the year avoiding seed damage. The delayed in soybean maturation by the increasing of [CO2] could potentially reduce yield; however the increase of temperature could diminish this risk by mitigating this delay. Alternatively, the more rapid progression through the reproductive stages could decrease the translocation of resources to pods, thereby negatively impacting yields. Using soybean as a model for leguminous C3 species suggested implications could arise for yield in crop plants and reproductive fitness in native vegetation.

Phthalates as developmental reproductive toxicants

EPA Science Inventory

PE are a large family ofcompounds used in a wide array ofconsumer, industrial and medical products. Studies have shown that in utero treatment with PE such as diethyl hexyl phthalate (DEHP) during the critical period offetal reproductive development produced male reproductive mal...

A DATABASE FOR TRACKING REPRODUCTIVE TOXICOGENOMIC DATA

EPA Science Inventory

A Database for Tracking Reproductive Toxicogenomic Data
Wenjun Bao, Judy Schmid, Amber Goetz, Hongzu Ren and David Dix
Reproductive Toxicology Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Pr...

Population, sexual and reproductive health, rights and sustainable development: forging a common agenda.

PubMed

Newman, Karen; Fisher, Sarah; Mayhew, Susannah; Stephenson, Judith

2014-05-01

This article suggests that sexual and reproductive health and rights activists seeking to influence the post-2015 international development paradigm must work with sustainable development advocates concerned with a range of issues, including climate change, environmental issues, and food and water security, and that a way of building bridges with these communities is to demonstrate how sexual and reproductive health and rights are relevant for these issues. An understanding of population dynamics, including urbanization and migration, as well as population growth, can help to clarify these links. This article therefore suggests that whether or not sexual and reproductive health and rights activists can overcome resistance to discussing "population", become more knowledgeable about other sustainable development issues, and work with others in those fields to advance the global sustainable development agenda are crucial questions for the coming months. The article also contends that it is possible to care about population dynamics (including ageing and problems faced by countries with a high proportion of young people) and care about human rights at the same time. It expresses concern that, if sexual and reproductive health and rights advocates do not participate in the population dynamics discourse, the field will be left free for those for whom respecting and protecting rights may be less of a priority. Copyright © 2014 Reproductive Health Matters. Published by Elsevier Ltd. All rights reserved.

Text recycling: acceptable or misconduct?

PubMed

Harriman, Stephanie; Patel, Jigisha

2014-08-16

Text recycling, also referred to as self-plagiarism, is the reproduction of an author's own text from a previous publication in a new publication. Opinions on the acceptability of this practice vary, with some viewing it as acceptable and efficient, and others as misleading and unacceptable. In light of the lack of consensus, journal editors often have difficulty deciding how to act upon the discovery of text recycling. In response to these difficulties, we have created a set of guidelines for journal editors on how to deal with text recycling. In this editorial, we discuss some of the challenges of developing these guidelines, and how authors can avoid undisclosed text recycling.

The role of the leptin in reproduction.

PubMed

Cervero, Ana; Domínguez, Francisco; Horcajadas, José A; Quiñonero, Alicia; Pellicer, Antonio; Simón, Carlos

2006-06-01

Since its discovery in 1994, leptin has appeared to be a pleiotrophic hormone, governing energy homeostasis and affecting many tissues in the body. Numerous pieces of evidence have accumulated showing that leptin potentially plays an important role in the control of the reproductive function. This review presents the major concepts for the role of leptin in the modulation of reproductive function. As a marker of the nutritional status, leptin affects the hypothalamo-pituitary-gonadal axis, regulating gonadotrophin-releasing hormone and luteinising hormone secretion, and appears to be a permissive factor in the onset of the puberty. This protein and its receptor have been found in the reproductive tissues, indicating that this system could be also implicated in several processes such as embryo development, implantation and pregnancy. Moreover, disorders of the leptin system have been related to some reproductive pathologies such as pre-eclampsia and polycystic ovary syndrome. However, controversy surrounds several aspects of the action of leptin in reproduction that require a deeper investigation of this system. Results to date suggest that this system could be implicated in important reproductive processes such as embryonic development and implantation. Moreover, understanding the role of leptin might be useful for new treatments in reproductive pathologies.

Endocrine control of epigenetic mechanisms in male reproduction.

PubMed

Ankolkar, Mandar; Balasinor, N H

2016-01-01

Endocrine control of reproduction is very well known and has been echoed by many research groups. However, recent developments point to the ability of toxic endocrine disrupting chemicals (EDC) to alter epigenetic information of the gametes which gets transferred to the developing embryo and affects the immediate reproductive outcome or even persists transgenerationally. These epigenetic aberrations contribute to the ensuing pathophysiology of reproductive disorders. Investigations of the female in cases of poor reproductive outcome have been the main strategy towards diagnosis. However, despite the male partner contributing half of his genome to the progeny, thorough investigations in the male have been ignored. Environmental pollutants are all pervading and are encountered in our day-to-day life. Many of these pollutants have potential to disrupt the endocrine system. Here, we discuss how the male gametes (spermatozoa) are susceptible to a myriad of epigenetic insults inflicted by exposure to endocrine disruptors and how important is the contribution of the epigenetic marks of the spermatozoa in healthy reproduction. We advocate that sperm epigenetics should be considered as a significant contributor to reproductive health and should be researched further and be subsequently included in routine diagnostic workup in cases of poor reproductive outcome.

Phosphorous Nutritional Level, Carbohydrate Reserves and Flower Quality in Olives.

PubMed

Erel, Ran; Yermiyahu, Uri; Yasuor, Hagai; Cohen Chamus, Dan; Schwartz, Amnon; Ben-Gal, Alon; Dag, Arnon

2016-01-01

The olive tree is generally characterized by relatively low final fruit set consequential to a significant rate of undeveloped pistils, pistil abortion, and flower and fruitlet abscission. These processes are acknowledged to be governed by competition for resources between the developing vegetative and reproductive organs. To study the role of phosphorus (P) nutritional level on reproductive development, trees were grown under four levels of P for three years in large containers. Phosphorus nutritional level was positively related to rate of reproductive bud break, inflorescence weight, rate of hermaphrodite flowers, pistil weight, fruitlet persistence, fruit set and the consequential total number of fruits. The positive impact of P nutrition on the productivity parameters was not related to carbohydrate reserves or to carbohydrate transport to the developing inflorescence. Phosphorous deficient trees showed significant impairment of assimilation rate, and yet, carbohydrates were accumulated in inflorescences at levels comparable to or higher than trees receiving high P. In contrast to female reproductive organs, pollen viability was consistently higher in P deficient trees, possibly due to the enhanced carbohydrate availability. Overall, the positive effect of P on female reproductive development was found to be independent of the total carbohydrate availability. Hence, P is speculated to have a direct influence on reproductive processes.

Sexual and reproductive health and rights in the evolving post-2015 agenda: perspectives from key players from multilateral and related agencies in 2013.

PubMed

Brolan, Claire E; Hill, Peter S

2014-05-01

This paper reports the views of participants from key multilaterals and related agencies in the evolving global negotiations on the post-2015 development agenda on the strategic location of sexual and reproductive health and rights. The research was carried out in June and July 2013, following the release of the report of the High-Level Panel of Eminent Persons on the Post-2015 Development Agenda, and comprised 40 semi-structured interviews with 57 participants and two e-mail respondents. All respondents were responsible for the post-2015 health and development agenda, or the post-2015 agenda more broadly, within their organisations. The interviews provide an insight into the intention to ensure that sexual and reproductive health and rights are integrated into the post-2015 trajectory by key players who sit at the interface of UN and Member State interaction. They reveal both an awareness of the shortcomings of the Millennium Development Goal process and its impact on advocacy for sexual and reproductive health and rights in early post-2015 engagement, as well as the vulnerability of sexual and reproductive health and rights in the remaining phases of post-2015 negotiations. Recent events bear these concerns out. Ensuring sexual and reproductive health and rights are included in the final post-2015 outcome document in the time remaining for negotiations, will be anything but a "doddle". Copyright © 2014 Reproductive Health Matters. Published by Elsevier Ltd. All rights reserved.

Higher reproductive success of small males and greater recruitment of large females may explain strong reversed sexual dimorphism (RSD) in the northern goshawk.

PubMed

Pérez-Camacho, L; García-Salgado, G; Rebollo, S; Martínez-Hesterkamp, S; Fernández-Pereira, J M

2015-02-01

Reversed sexual dimorphism (RSD), which occurs when the female of a species is larger than the male, is the rule for most birds of prey but the exception among other bird and mammal species. The selective pressures that favour RSD are an intriguing issue in animal ecology. Despite the large number of hypotheses proposed to explain the evolution of RSD, there is still no consensus about the mechanisms involved and whether they act on one or both sexes, mainly because few intrapopulation studies have been undertaken and few raptor species have been investigated. Using the strongly size-dimorphic northern goshawk (Accipiter gentilis L.) as a model, we studied a population with one of the highest densities of breeding pairs reported in the literature in order to understand selective pressures that may favour RSD. We evaluated life-history processes, including recruitment of adult breeders and reproductive success, and we explored the mechanisms thought to act on each sex, including hunting efficiency, diet, body condition and mate choice. We found that smaller males produced more fledglings than larger ones, but there was no relationship between size and reproductive success for females. The mean body size of female breeders was larger than that of female fledglings, but male fledglings and breeders did not differ in size. Male body size was related to the type but not to the amount of prey captured during the nestling stage. We conclude that RSD may be favoured in this goshawk population because small males tend to enjoy higher reproductive success and large females greater recruitment. Our results do not support the hypotheses that evolutionary reduction in male size is driven by hunting efficiency, at least during the nestling stage, or the hypotheses that it is driven by greater recruitment. Our findings also suggest that increase in female size is driven by recruitment, rather than by reproductive success as previously postulated.

The Effects of Disaster on Women's Reproductive Health in Developing Countries

PubMed Central

Swatzyna, Ronald J.; Pillai, Vijayan K.

2013-01-01

The objective of this study is to empirically test the effects of disasters which include natural as well as human made disasters such as armed conflict on women's reproductive health in developing countries. Data from 128 developing countries are used. It was found that average number of deaths from natural disasters and armed conflict in the East Asia and Pacific region was not significantly different from the rest of the developing world. The data are examined using structural equation analysis. This study finds that ‘armed conflict’ in developing countries presents significant reproductive health risks. The implications are discussed. PMID:23777727

Intraspecific variation in body size and the rate of reproduction in female insects - adaptive allometry or biophysical constraint?

PubMed

Berger, David; Olofsson, Martin; Friberg, Magne; Karlsson, Bengt; Wiklund, Christer; Gotthard, Karl

2012-11-01

1. A high rate of reproduction may be costly if ecological factors limit immediate reproductive output as a fast metabolism compromises own future survival. Individuals with more reserves need more time and opportunity to realize their reproductive potential. Theory therefore predicts that the reproductive rate, defined as the investment in early reproduction in proportion to total potential, should decrease with body size within species. 2. However, metabolic constraints on body size- and temperature-dependent biological rates may impede biophysical adaptation. Furthermore, the sequential manner resources that are allocated to somatic vs. reproductive tissue during ontogeny may, when juveniles develop in unpredictable environments, further contribute to non-adaptive variation in adult reproductive rates. 3. With a model on female egg laying in insects, we demonstrate how variation in body reserves is predicted to affect reproductive rate under different ecological scenarios. Small females always have higher reproductive rates but shorter lifespans. However, incorporation of female host selectivity leads to more similar reproductive rates among female size classes, and oviposition behaviour is predicted to co-evolve with reproductive rate, resulting in small females being more selective in their choice and gaining relatively more from it. 4. We fed simulations with data on the butterfly Pararge aegeria to compare model predictions with reproductive rates of wild butterflies. However, simulated reproductive allometry was a poor predictor of that observed. Instead, reproductive rates were better explained as a product of metabolic constraints on rates of egg maturation, and an empirically derived positive allometry between reproductive potential and size. However, fitness is insensitive to moderate deviations in reproductive rate when oviposition behaviour is allowed to co-evolve in the simulations, suggesting that behavioural compensation may mitigate putative metabolic and developmental constraints. 5. More work is needed to understand how physiology and development together with compensatory behaviours interact in shaping reproductive allometry. Empirical studies should evaluate adaptive hypotheses against proper null hypotheses, including prediction from metabolic theory, preferentially by studying reproductive physiology in combination with behaviour. Conversely, inferences of constraint explanations on reproductive rates must take into consideration that adaptive scenarios may predict similar allometric exponents. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.

Inequity in India: the case of maternal and reproductive health

PubMed Central

Sanneving, Linda; Trygg, Nadja; Saxena, Deepak; Mavalankar, Dileep; Thomsen, Sarah

2013-01-01

Background Millennium Development Goal (MDG) 5 is focused on reducing maternal mortality and achieving universal access to reproductive health care. India has made extensive efforts to achieve MDG 5 and in some regions much progress has been achieved. Progress has been uneven and inequitable however, and many women still lack access to maternal and reproductive health care. Objective In this review, a framework developed by the Commission on Social Determinants of Health (CSDH) is used to categorize and explain determinants of inequity in maternal and reproductive health in India. Design A review of peer-reviewed, published literature was conducted using the electronic databases PubMed and Popline. The search was performed using a carefully developed list of search terms designed to capture published papers from India on: 1) maternal and reproductive health, and 2) equity, including disadvantaged populations. A matrix was developed to sort the relevant information, which was extracted and categorized based on the CSDH framework. In this way, the main sources of inequity in maternal and reproductive health in India and their inter-relationships were determined. Results Five main structural determinants emerged from the analysis as important in understanding equity in India: economic status, gender, education, social status (registered caste or tribe), and age (adolescents). These five determinants were found to be closely interrelated, a feature which was reflected in the literature. Conclusion In India, economic status, gender, and social status are all closely interrelated when influencing use of and access to maternal and reproductive health care. Appropriate attention should be given to how these social determinants interplay in generating and sustaining inequity when designing policies and programs to reach equitable progress toward improved maternal and reproductive health. PMID:23561028

Expression analysis of fertilization/early embryogenesis-associated genes in Phalaenopsis orchids.

PubMed

Chen, Jhun-Chen; Wei, Miao-Ju; Fang, Su-Chiung

2016-10-02

One of the distinct reproductive programs in orchid species is pollination-triggered ovule development and megasporogenesis. During sexual reproduction, fertilization occurs days to months after pollination. The molecular mechanisms evolved to carry out this strategic reproductive program remain unclear. In the August issue of Plant Physiology 1 , we report comprehensive studies of comparative genome-wide gene expression in various reproductive tissues and the molecular events associated with developmental transitions unique to sexual reproduction of Phalaenopsis aphrodite. Transcriptional factors and signaling components whose expression is specifically enriched in interior ovary tissues when fertilization occurs and embryos start to develop have been identified. Here, we report verification of additional fertilization-associated genes, DOMAINS REARRANGED METHYLTRANSFERASE 1 (PaDRM1), CHROMOMETHYLTRANSFERASE 1 (PaCMT1), SU(VAR)3-9 RELATED PROTEIN 1 (PaSUVR1), INDOLE-3-ACETIC ACID inducible 30-like 1 (PaIAA30L1), and ETHYLENE INSENSITIVE 3-like 1 (PaEIN3L1), and discuss their potential roles in gametophyte development, epigenetic reprogramming, and hormone regulation during fertilization and establishment of embryo development in Phalaenopsis orchids.

Reproductive health/family planning and the health of infants, girls and women.

PubMed

Sadik, N

1997-01-01

The 1994 International Conference on Population and Development developed international consensus amongst health providers, policy makers, and group representing the whole of civil society regarding the concept of reproductive health and its definition. In line with this definition, reproductive health care is defined as the constellation of methods, techniques and services that contribute to reproductive health and well-being by preventing and solving reproductive health problems. Reproductive health care saves lives and prevents significant levels of morbidity through family planning programmes, antenatal, delivery and post-natal services, prevention and management programmes for reproductive tract infections (including sexually transmitted diseases and HIV/AIDS), prevention of abortion and management of its complications, cancers of the reproductive system, and harmful practices that impact on reproductive function. Reproductive health care needs are evident at all stages of the life cycle and account for a greater proportion of disability adjusted life years (DALYS) in girls and women than in boys and men. Reproductive health protects infant health by enabling birth spacing and birth limitation to be practiced through family planning. The prevention and early detection of reproductive tract infections, including sexually transmitted diseases and HIV, through the integration of preventive measures in family planning service delivery not only improves the quality of care provided but is also directly responsible for improvement in survival and health of infants. Addressing harmful practices such as son preference, sex selection, sexual violence and female genital mutilation complements the positive impact of planned and spaced children through family planning services on infant mortality and the reproductive health of young girls and women. They are also in addition to prenatal, delivery and postnatal services, positive determinants of low maternal mortality and morbidity and are integral to the promotion of reproductive health in women of child bearing age. Reproductive tract infections, including sexually transmitted diseases and HIV contribute to significant level of ill-health in women of reproductive age and continue to pose a threat through the menopause which in turn brings with it increasing risk of cancers of the reproductive system.

Plant germline formation: common concepts and developmental flexibility in sexual and asexual reproduction.

PubMed

Schmidt, Anja; Schmid, Marc W; Grossniklaus, Ueli

2015-01-15

The life cycle of flowering plants alternates between two heteromorphic generations: a diploid sporophytic generation and a haploid gametophytic generation. During the development of the plant reproductive lineages - the germlines - typically, single sporophytic (somatic) cells in the flower become committed to undergo meiosis. The resulting spores subsequently develop into highly polarized and differentiated haploid gametophytes that harbour the gametes. Recent studies have provided insights into the genetic basis and regulatory programs underlying cell specification and the acquisition of reproductive fate during both sexual reproduction and asexual (apomictic) reproduction. As we review here, these recent advances emphasize the importance of transcriptional, translational and post-transcriptional regulation, and the role of epigenetic regulatory pathways and hormonal activity. © 2015. Published by The Company of Biologists Ltd.

Pollination crisis in the butterfly-pollinated wild carnation Dianthus carthusianorum?

PubMed

Bloch, Daniel; Werdenberg, Niels; Erhardt, Andreas

2006-01-01

Knowledge of pollination services provided by flower visitors is a prerequisite for understanding (co)evolutionary processes between plants and their pollinators, for evaluating the degree of specialization in the pollination system, and for assessing threats from a potential pollination crisis. This study examined pollination efficiency and visitation frequency of pollinators--key traits of pollinator-mediated fecundity--in a natural population of the wild carnation Dianthus carthusianorum. The five lepidopteran pollinator species observed differed in pollination efficiency and visitation frequency. Pollinator importance, the product of pollination efficiency and visitation frequency, was determined by the pollinator's visitation frequency. Pollination of D. carthusianorum depended essentially on only two of the five recorded pollinator species. Seed set was pollen-limited and followed a saturating dose-response function with a threshold of c. 50 deposited pollen grains for fruit development. Our results confirm that D. carthusianorum is specialized to lepidopteran pollinators, but is not particularly adapted to the two main pollinator species identified. The local persistence of D. carthusianorum is likely to be at risk as its reproduction depends essentially on only two of the locally abundant, but generally vulnerable, butterfly species.

Land-based production of animal protein: impacts, efficiency, and sustainability.

PubMed

Wu, Guoyao; Bazer, Fuller W; Cross, H Russell

2014-11-01

Land-based production of high-quality protein by livestock and poultry plays an important role in improving human nutrition, growth, and health, as well as economical and social developments worldwide. With exponential growth of the global population and marked rises in meat consumption per capita, demands for animal-source protein are expected to increase by 72% between 2013 and 2050. This raises concerns about the sustainability and environmental impacts of animal agriculture. An attractive solution to meeting the increasing needs for animal products and mitigating undesired effects of agricultural practices is to enhance the efficiency of animal growth, reproduction, and lactation. Breeding techniques may help achieve this goal, but have only met with limited success. A promising, mechanism-based approach is to optimize the proportion and amounts of amino acids in diets for maximizing whole-body protein synthesis and feed efficiency. Improvements in farm animal productivity will not only decrease the contamination of soils, groundwater, and air by excessive manure, but will also help sustain animal agriculture to produce high-quality protein for the expanding population in the face of diminishing resources. © 2014 New York Academy of Sciences.

Life history strategy of the honey bee, Apis mellifera.

PubMed

Seeley, Thomas D

1978-01-01

The feral honey bee queens (colonies) of central New York State (USA) show a K-type life history strategy. Their demographic characteristics include low early life mortality, low reproductive rate, long lifespan, high population stability and repeated reproductions. Identifying the life history strategy of these bees reveals the general pattern of selection for competitive ability, rather than productivity, which has shaped their societies. Selection for competitive power explains the adaptiveness (compared with alternatives found in many other insect societies) of the large perennial colonies, infrequent but expensive offspring, and efficient foraging which characterize the social organization of these bees.

ACCUMULATION AND EFFECTS OF PFOS ON THE REPRODUCTIVE ENDOCRINOLOGY OF THE FATHEAD MINNOW

EPA Science Inventory

Perfluorooctane sulfonate (PFOS) is a globally-distributed contaminant in fish and wildlife. Comparatively little is known, however, concerning potential adverse effects of PFOS on reproduction and development of fish. There is some indication that PFOS could affect reproductive ...

The impact of environmental stress on male reproductive development in plants: biological processes and molecular mechanisms

PubMed Central

de Storme, Nico; Geelen, Danny

2014-01-01

In plants, male reproductive development is extremely sensitive to adverse climatic environments and (a)biotic stress. Upon exposure to stress, male gametophytic organs often show morphological, structural and metabolic alterations that typically lead to meiotic defects or premature spore abortion and male reproductive sterility. Depending on the type of stress involved (e.g. heat, cold, drought) and the duration of stress exposure, the underlying cellular defect is highly variable and either involves cytoskeletal alterations, tapetal irregularities, altered sugar utilization, aberrations in auxin metabolism, accumulation of reactive oxygen species (ROS; oxidative stress) or the ectopic induction of programmed cell death (PCD). In this review, we present the critically stress-sensitive stages of male sporogenesis (meiosis) and male gametogenesis (microspore development), and discuss the corresponding biological processes involved and the resulting alterations in male reproduction. In addition, this review also provides insights into the molecular and/or hormonal regulation of the environmental stress sensitivity of male reproduction and outlines putative interaction(s) between the different processes involved. PMID:23731015

Frost resistance of reproductive tissues during various stages of development in high mountain plants.

PubMed

Neuner, Gilbert; Erler, Agnes; Ladinig, Ursula; Hacker, Jürgen; Wagner, Johanna

2013-01-01

Frost resistance of reproductive vs aboveground vegetative structures was determined for six common European high alpine plant species that can be exposed to frosts throughout their whole reproductive cycle. Freezing tests were carried out in the bud, anthesis and fruit stage. Stigma and style, ovary, placenta, ovule, flower stalk/peduncle and, in Ranunculus glacialis, the receptacle were separately investigated. In all species, the vegetative organs tolerated on an average 2-5 K lower freezing temperatures than the most frost-susceptible reproductive structures that differed in their frost resistance. In almost all species, stigma, style and the flower stalk/peduncle were the most frost-susceptible reproductive structures. Initial frost damage (LT₁₀) to the most susceptible reproductive structure usually occurred between -2 and -4°C independent of the reproductive stage. The median LT₅₀ across species for stigma and style ranged between -3.4 and -3.7°C and matched the mean ice nucleation temperature (-3.7 ± 1.4°C). In R. glacialis, the flower stalk was the most frost-susceptible structure (-5.4°C), and was in contrast to the other species ice-tolerant. The ovule and the placenta were usually the most frost-resistant structures. During reproductive development, frost resistance (LT₅₀) of single reproductive structures mostly showed no significant change. However, significant increases or decreases were also observed (2.1 ± 1.2 K). Reproductive tissues of nival species generally tolerated lower temperatures than species occurring in the alpine zone. The low frost resistance of reproductive structures before, during and shortly after anthesis increases the probability of frost damage and thus, may restrict successful sexual plant reproduction with increasing altitude. Copyright © Physiologia Plantarum 2012.

Age-dependent trade-offs between immunity and male, but not female, reproduction.

PubMed

McNamara, Kathryn B; van Lieshout, Emile; Jones, Therésa M; Simmons, Leigh W

2013-01-01

Immune function is costly and must be traded off against other life-history traits, such as gamete production. Studies of immune trade-offs typically focus on adult individuals, yet the juvenile stage can be a highly protracted period when reproductive resources are acquired and immune challenges are ubiquitous. Trade-offs during development are likely to be important, yet no studies have considered changes in adult responses to immune challenges imposed at different stages of juvenile development. By manipulating the timing of a bacterial immune challenge to the larvae of the cotton bollworm moth, we examined potential trade-offs between investment into immunity at different stages of juvenile development (early or late) and subsequent adult reproductive investment into sperm or egg production. Our data reveal an age-dependent trade-off between juvenile immune function and adult male reproductive investment. Activation of the immune response during late development resulted in a reduced allocation of resources to eupyrene (fertilizing) sperm production. Immune activation from the injection procedure itself (irrespective of whether individuals were injected with an immune elicitor or a control solution) also caused reproductive trade-offs; males injected early in development produced fewer apyrene (nonfertilizing) sperm. Contrary to many other studies, our study demonstrates these immune trade-offs under ad libitum nutritional conditions. No trade-offs were observed between female immune activation and adult reproductive investment. We suggest the differences in trade-offs observed between male sperm types and the absence of reproductive trade-offs in females may be the result of ontogenetic differences in gamete production in this species. Our data reveal developmental windows when trade-offs between immune function and gametic investment are made, and highlight the importance of considering multiple developmental periods when making inferences regarding the fundamental trade-offs expected between immune function and reproduction. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.

Time‐efficient and flexible design of optimized multishell HARDI diffusion

PubMed Central

Tournier, J. Donald; Price, Anthony N.; Cordero‐Grande, Lucilio; Hughes, Emer J.; Malik, Shaihan; Steinweg, Johannes; Bastiani, Matteo; Sotiropoulos, Stamatios N.; Jbabdi, Saad; Andersson, Jesper; Edwards, A. David; Hajnal, Joseph V.

2017-01-01

Purpose Advanced diffusion magnetic resonance imaging benefits from collecting as much data as is feasible but is highly sensitive to subject motion and the risk of data loss increases with longer acquisition times. Our purpose was to create a maximally time‐efficient and flexible diffusion acquisition capability with built‐in robustness to partially acquired or interrupted scans. Our framework has been developed for the developing Human Connectome Project, but different application domains are equally possible. Methods Complete flexibility in the sampling of diffusion space combined with free choice of phase‐encode‐direction and the temporal ordering of the sampling scheme was developed taking into account motion robustness, internal consistency, and hardware limits. A split‐diffusion‐gradient preparation, multiband acceleration, and a restart capacity were added. Results The framework was used to explore different parameters choices for the desired high angular resolution diffusion imaging diffusion sampling. For the developing Human Connectome Project, a high‐angular resolution, maximally time‐efficient (20 min) multishell protocol with 300 diffusion‐weighted volumes was acquired in >400 neonates. An optimal design of a high‐resolution (1.2 × 1.2 mm2) two‐shell acquisition with 54 diffusion weighted volumes was obtained using a split‐gradient design. Conclusion The presented framework provides flexibility to generate time‐efficient and motion‐robust diffusion magnetic resonance imaging acquisitions taking into account hardware constraints that might otherwise result in sub‐optimal choices. Magn Reson Med 79:1276–1292, 2018. © 2017 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. PMID:28557055

Male subfertility and the role of micronutrient supplementation: clinical and economic issues

PubMed Central

Salma, Umme; Gill, Harjinder Kaur; Keith, Louis G.; Tilmon, Sandra; Jones, Christopher A.; Sobti, Anjali; Patel, Ashlesha

2011-01-01

The concept of male subfertility has evolved rapidly since 2000. This term is discussed based upon evidence relating to its first entrance into the literature, along with contemporary references to its purported incidence and prevalence. Factors affecting sperm quality are described in detail, and available data pertaining to the effects of micronutrients on spermatic parameters and resulting pregnancies are described. The first cost-efficiency analysis of the use of micronutrients vs. assisted reproductive technologies is presented. This paper also describes a therapeutic approach to males, recognizing that many potential fathers have no recourse to medical facilities to evaluate their fertility. At a time when medical dollars are either nonexistent or precious, such an approach using micronutrient supplementation may be cost-effective in developing and possibly even in developed countries. PMID:21991290

Unrelated secondary reproductives in the neotropical termite Silvestritermes euamignathus (Isoptera: Termitidae)

NASA Astrophysics Data System (ADS)

Haifig, Ives; Vargo, Edward L.; Labadie, Paul; Costa-Leonardo, Ana Maria

2016-02-01

A termite colony is usually founded by a pair of alates, the primary reproductives, which produce all the nestmates. In some species, secondary reproductives appear to either replace the primaries or supplement colony reproduction. In termites, secondary reproductives are generally ergatoids derived from workers or nymphoids derived from nymphs. Silvestritermes euamignathus is a termite species that forms multiple nymphoid reproductives, and to date it was hypothesized that these secondary reproductives were the progeny of the primary founding reproductives. We developed markers for 12 microsatellite loci and used COI mitochondrial DNA (mtDNA) to genotype 59 nymphoid neotenics found in a colony of S. euamignathus to test this hypothesis. Our results showed that nymphoids of S. euamignathus are not all siblings. The microsatellite analysis suggests that the secondary reproductives derived from a minimum of four different pairs of reproductives belonging to at least two different matrilines. This is the first record of non-sibling secondary reproductives occupying the same nest in a higher termite. These unrelated reproductives might be the result of either pleometrotic colony foundation or colony fusion.

Effects of parasite pressure on parasite mortality and reproductive output in a rodent-flea system: inferring host defense trade-offs.

PubMed

Warburton, Elizabeth M; Kam, Michael; Bar-Shira, Enav; Friedman, Aharon; Khokhlova, Irina S; Koren, Lee; Asfur, Mustafa; Geffen, Eli; Kiefer, Daniel; Krasnov, Boris R; Degen, A Allan

2016-09-01

Evaluating host resistance via parasite fitness helps place host-parasite relationships within evolutionary and ecological contexts; however, few studies consider both these processes simultaneously. We investigated how different levels of parasite pressure affect parasite mortality and reproductive success in relationship to host defense efforts, using the rodent Gerbillus nanus and the flea Xenopsylla conformis as a host-parasite system. Fifteen immune-naïve male rodents were infested with 20, 50, or 100 fleas for four weeks. During this time number of new imagoes produced per adult flea (our flea reproductive output metric), flea mortality, and change in circulating anti-flea immunoglobulin G (our measure of adaptive immune defense) were monitored. Three hypotheses guided this work: (1) increasing parasite pressure would heighten host defenses; (2) parasite mortality would increase and parasite reproductive output would decrease with increasing investment in host defense; and (3) hosts under high parasite pressure could invest in behavioral and/or immune responses. We predicted that at high infestation levels (a) parasite mortality would increase; (b) flea reproductive output per individual would decrease; and (c) host circulating anti-flea antibody levels would increase. The hypotheses were partially supported. Flea mortality significantly increased and flea reproductive output significantly decreased as flea pressure increased. Host adaptive immune defense did not significantly change with increasing flea pressure. Therefore, we inferred that investment in host behavioral defense, either alone or in combination with density-dependent effects, may be more efficient at increasing flea mortality and decreasing flea reproductive output than antibody production during initial infestation in this system.

Developing Predictive Approaches to Characterize Adaptive Responses of the Reproductive Endocrine Axis to Aromatase Inhibition II: Computational Modeling

EPA Science Inventory

ABSTRACT Exposure to endocrine disrupting chemicals can affect reproduction and development in both humans and wildlife. We developed a mechanistic mathematical model of the hypothalamic­ pituitary-gonadal (HPG) axis in female fathead minnows to predic...

Human reproduction: Jewish perspectives.

PubMed

Schenker, Joseph G

2013-11-01

Developments in science and technology and corresponding clinical applications raise new religious questions, often without clear answers. The role of theology in bioethics is integral to clarify perceived attitudes toward these developments for different religious communities. The Jewish attitude towards procreation is derived from the first commandment of God to Adam to 'Be fruitful and multiply'. Judaism allows the practice of all techniques of assisted reproduction when the oocyte and spermatozoon originate from the wife and husband respectively. This paper presents the attitude of Jewish Law -- Halacha to therapeutic procedures, such as IVF-embryo transfer, spermatozoa, oocytes, embryo donation, cryopreservation of genetic material, surrogacy, posthumous reproduction, gender preselection, reproductive and therapeutic cloning.

Effects of short-term grazing exclusion on plant phenology and reproductive succession in a Tibetan alpine meadow.

PubMed

Zhu, Juntao; Zhang, Yangjian; Liu, Yaojie

2016-06-15

Grazing exclusion (GE) has been widely considered as an effective avenue for restoring degraded grasslands throughout the world. GE, via modifying abiotic and biotic environments, inevitably affects phenological development. A five-year manipulative experiment was conducted in a Tibetan alpine meadow to examine the effects of GE on phenological processes and reproductive success. The study indicated that GE strongly affected phenological development of alpine plant species. Specifically, the low-growing, shallow-rooted species (LSS), such as Kobresia pygmaea, are more sensitive to GE-caused changes on upper-soil moisture and light. GE advanced each phonological process of K. pygmaea, except in the case of the treatment of fencing for 5 years (F5), which postponed the reproductive stage and lowered the reproductive success of K. pygmaea. Increased soil moisture triggered by GE, especially in the upper soil, may stimulate growth of LSS. However, the thick litter layer under the F5 treatment can influence the photoperiod of LSS, resulting in suppression of its reproductive development. These findings indicate that plant traits associated with resource acquisition, such as rooting depth and plant height, mediate plant phenology and reproductive responses to grazing exclusion treatments.

[Explore microcosmic connection between autophagy mechanism and follicular development based on "kidney governing reproduction" theory].

PubMed

Bai, Jun; Wu, Ke-Ming; Gao, Ran-Ran

2018-03-01

In the theory of traditional Chinese medicine(TCM) that "kidney storing essence and governing reproduction", reproductive essence is an important part of the kidney essence and acts as the original material of offspring embryos. Sperm, oocyte and zygote should be all included in the range of reproductive essence. Ovum is the essence of reproduction from inborn. The follicles maturation depends on the quality of oocyte and the vigor of kidney essence. Meanwhile, discharge of mature ovum relies on the stimulation and promotion by kidney Qi. Autophagy almost exists in different cells stages and all various of mammalian cells. Many studies have found that autophagy not only participates in the formation of follicles, but also in every phase of the follicles development, and is involved in the occurrence and development of ovarian diseases. Recently, more and more scholars believe that autophagy is a new field to explore the microcosmic relationship between autophagy and TCM. Kidney-nourishing TCM could promote follicular growth and improve variety clinical symptoms by inhibiting the apoptosis of ovarian granulosa cells and reducing follicular atresia. Meanwhile, apoptosis of ovarian granulosa cells is closely related to autophagy of ovarian granulosa cells. In order to provide some theoretical foundation for kidney-nourishing therapy's promoting effect on follicular growth and improving effect on ovarian function, also to further explore the molecular mechanism of kidney-nourishing medicine in promoting follicular development, this paper would explain the microcosmic relationship between autophagy and follicular development based on the theory of "kidney governing reproduction". All of these would be of great significance to prevent and intervene the diseases of reproductive system timely and effectively. Copyright© by the Chinese Pharmaceutical Association.

Fern Gametophytes in Culture--A Simple System for Studying Plant Development and Reproduction.

ERIC Educational Resources Information Center

Dyer, A. F.

1983-01-01

Discusses fern life cycle and basic techniques for culturing fern gametophytes in the classroom. Also discusses investigations into the reproductive biology of ferns and into the early development of gametophytes. (JN)

Oxidative shielding and the cost of reproduction.

PubMed

Blount, Jonathan D; Vitikainen, Emma I K; Stott, Iain; Cant, Michael A

2016-05-01

Life-history theory assumes that reproduction and lifespan are constrained by trade-offs which prevent their simultaneous increase. Recently, there has been considerable interest in the possibility that this cost of reproduction is mediated by oxidative stress. However, empirical tests of this theory have yielded equivocal support. We carried out a meta-analysis to examine associations between reproduction and oxidative damage across markers and tissues. We show that oxidative damage is positively associated with reproductive effort across females of various species. Yet paradoxically, categorical comparisons of breeders versus non-breeders reveal that transition to the reproductive state is associated with a step-change reduction in oxidative damage in certain tissues and markers. Developing offspring may be particularly sensitive to harm caused by oxidative damage in mothers. Therefore, such reductions could potentially function to shield reproducing mothers, gametes and developing offspring from oxidative insults that inevitably increase as a consequence of reproductive effort. According to this perspective, we hypothesise that the cost of reproduction is mediated by dual impacts of maternally-derived oxidative damage on mothers and offspring, and that mothers may be selected to diminish such damage. Such oxidative shielding may explain why many existing studies have concluded that reproduction has little or no oxidative cost. Future advance in life-history theory therefore needs to take account of potential transgenerational impacts of the mechanisms underlying life-history trade-offs. © 2015 Cambridge Philosophical Society.

Di-isoheptyl Phthalate (DIHP) in utero exposure reduces testicular testosterone (T) production in fetal Sprague Dawley (SD) rats

EPA Science Inventory

Exposure to DIHP, a commercial phthalate ester plasticizer used in flooring manufacturing, during the fetal period of sexual differentiation disrupts male reproductive development resulting in reproductive malformations and reduced androgen-dependent reproductive tissue weights i...

Incorporating Temperature-driven Seasonal Variation in Survival, Growth, and Reproduction Models for Small Fish

EPA Science Inventory

Seasonal variation in survival and reproduction can be a large source of prediction uncertainty in models used for conservation and management. A seasonally varying matrix population model is developed that incorporates temperature-driven differences in mortality and reproduction...

Current knowledge and future challenges in camelid reproduction.

PubMed

Tibary, A; Anouassi, A; Sghiri, A; Khatir, H

2007-01-01

Reproductive biology research on camelids offers some interesting peculiarities and challenges to scientists and animal production specialists. The objective of this paper is to review camelid reproduction, advances in reproductive physiology and reproductive biotechnologies in camelids and discuss some areas for further research. In the female, the focus has been on understanding follicular dynamics. This has allowed development of synchronization and superovulation strategies to support embryo transfer technologies which are now commonly used in camels. Some advances have been achieved in preservation of embryos by vitrification. Fertilization, early embryo development and embryo signaling for maternal recognition of pregnancy are still not fully understood. New information on the interaction of the developing embryo and the endometrium may shed some light on this signaling as well as the mechanism of prevention of luteolysis. The presence of a seminal ovulation-inducing factor (OIF) was confirmed in llamas and alpacas. Chronology of oocytes maturation has been described. In vitro production of embryos has been achieved resulting in successful pregnancies and births in the dromedary. These techniques offer a new tool for the production and study of interspecies/cross-species embryos and their effect on pregnancy. Male reproductive function remains poorly studied. Semen preservation and artificial insemination still present many challenges and are not used in production at the moment. The involvement of climatic and nutritional conditions as well as the role of leptin in the regulation of reproductive function need to be evaluated.

The role of tyramine and octopamine in the regulation of reproduction in queenless worker honeybees

NASA Astrophysics Data System (ADS)

Salomon, Mor; Malka, Osnat; Meer, Robert K. Vander; Hefetz, Abraham

2012-02-01

In honeybees, workers under queenless condition compete for reproduction and establish reproductive dominance hierarchy. Ovary activation is generally accompanied by the expression of queen-like pheromones. Biogenic amines (BAs), in particular dopamine, are believed to be involved in this process by regulating ovarian development. However, the role of BAs in establishing reproductive dominance or their effect on queen-like pheromone production was not investigated. Here, we explored the effect of octopamine (OA) and tyramine (TA) oral treatments on the propensity of treated bees to become reproductively dominant and produce queen-like pheromones in Dufour's and mandibular glands. One bee in a pair was treated with either OA or TA while the other was fed sugar solution. TA was found to enhance ovary development and the production of esters in the Dufour's gland and 9HDA (queen component) in the mandibular glands, thus facilitating worker reproductive dominance. OA, on the other hand, did not enhance ovarian development or ester production, but increased the production of 10HDA (worker major component) in the mandibular glands of their sugar-paired mates. OA is known to induce foraging behavior by workers, while increased production of 10HDA characterizes nursing workers. Therefore, we suggest that TA induces reproductive division of labor, while OA treatment results in caste differentiation of workers to foragers and nurses.

Hormonal regulation of reproductive growth under normal and heat-stress conditions in legume and other model crop species.

PubMed

Ozga, Jocelyn A; Kaur, Harleen; Savada, Raghavendra P; Reinecke, Dennis M

2017-04-01

Legume crops are grown throughout the world and provide an excellent food source of digestible protein and starch, as well as dietary fibre, vitamins, minerals, and flavonoids. Fruit and seeds from legumes are also an important source of vegetables for a well-balanced diet. A trend in elevated temperature as a result of climate change increases the risk of a heat stress-induced reduction in legume crop yield. High temperatures during the crop reproductive development phase are particularly detrimental to fruit/seed production because the growth and development of the reproductive tissues are sensitive to small changes in temperature. Hormones are signalling molecules that play important roles in a plant's ability to integrate different environmental inputs and modify their developmental processes to optimize growth, survival, and reproduction. This review focuses on the hormonal regulation of reproductive development and heat stress-induced alteration of this regulation during (i) pollination, (ii) early fruit set, and (iii) seed development that affects fruit/seed yield in legume and other model crops. Further understanding of hormone-regulated reproductive growth under non-stress and heat-stress conditions can aid in trait selection and the development of gene modification strategies and cultural practices to improve heat tolerance in legume crops contributing to improved food security. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

The mixed mating system of the sea palm kelp Postelsia palmaeformis: few costs to selfing

PubMed Central

Barner, Allison K.; Pfister, Catherine A.; Wootton, J. Timothy

2011-01-01

Naturally isolated populations have conflicting selection pressures for successful reproduction and inbreeding avoidance. These species with limited seasonal reproductive opportunities may use selfing as a means of reproductive assurance. We quantified the frequency of selfing and the fitness consequences for inbred versus outcrossed progeny of an annual kelp, the sea palm (Postelsia palmaeformis). Using experimentally established populations and microsatellite markers to assess the extent of selfing in progeny from six founding parents, we found the frequency of selfing was higher than expected in every population, and few fitness costs were detected in selfed offspring. Despite a decline in heterozygosity of 30 per cent in the first generation of selfing, self-fertilization did not affect individual size or reproduction, and correlated only with a marginally significant decline in survival. Our results suggest both that purging of deleterious recessive alleles may have already occurred and that selfing may be key to reproductive assurance in this species with limited dispersal. Postelsia has an alteration of a free-living diploid and haploid stage, where the haploid stage may provide increased efficiency for purging the genetic load. This life history is shared by many seaweeds and may thus be an important component of mating system evolution in the sea. PMID:20961896

Developing Predictive Approaches to Characterize Adaptive Responses of the Reproductive Endocrine Axis to Aromatase Inhibition: Computational Modeling

EPA Science Inventory

Exposure to endocrine disrupting chemicals can affect reproduction and development in both humans and wildlife. We developed a mechanistic mathematical model of the hypothalamic-pituitary-gonadal (HPG) axis in female fathead minnows to predict dose-response and time-course (DRTC)...

Windows of susceptibility and consequences of early life exposures to 17β–estradiol on medaka (Oryzias latipes) reproductive success

USGS Publications Warehouse

Lee Pow, Crystal S. D.; Tilahun, Kedamawit; Creech, Kari; Law, J. Mac; Cope, W. Gregory; Kwak, Thomas J.; Rice, James A.; Aday, D. Derek; Kullman, Seth W.

2017-01-01

Estrogens and estrogen mimics are commonly found in surface waters and are associated with deleterious effects in fish populations. Impaired fertility and fecundity in fish following chronic exposures to estrogens and estrogen mimics during critical windows in development are well documented. However, information regarding differential reproductive effects of exposure within defined developmental stages remains sparse. In this study, reproductive capacity was assessed in Japanese medaka (Oryzias latipes) after exposure to two concentrations of 17β–estradiol (E2β; 2 ng/L and 50 ng/L) during four distinct stages of development: gonad development, gonad differentiation, development of secondary sex characteristics (SSC) and gametogenesis. Exposure to E2β did not adversely impact survival, hatch success, growth, or genotypic ratios. In contrast, exposure to 50 ng/L E2β during SSC development altered phenotypic ratios and SSC. Exposure to both E2β treatments reduced reproductive capacity (fertility, fecundity) by 7.3–57.4% in adult medaka breeding pairs, with hindrance of SSC development resulting in the largest disruption in breeding capacity (51.6–57.4% decrease) in the high concentration. This study documents differential effects among four critical stages of development and provides insight into factors (window of exposure, exposure concentration and duration of exposure period) contributing to reproductive disruption in fish.

Is a Water Content of 60% Maximum Water Holding Capacity Suitable for Folsomia candida Reproduction Tests? A Study with Silver Nanoparticles and AgNO3

PubMed Central

McKee, Moira S.; Megía Guerrero, Amelia; Filser, Juliane

2018-01-01

Silver nanoparticles (AgNP) are increasingly emitted to the environment due to a rise in application in various products; therefore, assessment of their potential risks for biota is important. In this study the effects of AgNP at environmentally relevant concentrations (0.6–375 µg kg−1 soil) on the soil invertebrate Folsomia candida in OECD (Organisation for Economic Co-operation and Development) soil was examined at different soil water contents. Animals were retrieved by heat extraction, which had an efficiency of about 90% compared with the floatation method. The tested water content range is set by OECD Guideline 232 (40–60% of the maximum water holding capacity, WHC), and we detected significant differences in toxicity due to these. With AgNO3, used as an ionic control, the number of juveniles significantly decreased only at 40% WHC, which might be due to dilution of the toxicant at higher soil water content. In turn, at 60% WHC, the reproduction of F. candida significantly increased in the presence of AgNP compared with in the control. However, at this water content, the required number of juveniles in the control treatment was not reached in three independent tests. The fact that the OECD validity criterion is not met indicates that the soil conditions are not suitable for reproduction at 60% WHC. PMID:29614765

Current Development in Reproductive Toxicity Testing of Pesticides

EPA Science Inventory

A protocol to evaluate the potential developmental and reproductive effects of test chemicals has been developed by the Life Stages Task Force of the International Life Sciences Institute (ILSI)/Health and Environmental Sciences Institute (HESI) Agricultural Chemical Safety Asses...

EFFECTS OF ENVIRONMENTAL ANTIANDROGENS ON REPRODUCTIVE DEVELOPMENT IN EXPERIMENTAL ANIMALS

EPA Science Inventory

In mammals, the androgens testosterone (T) and dihydrotestosterone (DHT) are critical for normal male reproductive development and function. In humans, drugs that act as androgen receptor (AR) agonists and antagonists or inhibit fetal steroidogenesis can cause pseudohermaphrodi...

Reproduction capacity of Potamogeton crispus fragments and its role in water purification and algae inhibition in eutrophic lakes.

PubMed

Zhou, Yiwen; Zhou, Xiaohong; Han, Ruiming; Xu, Xiaoguang; Wang, Guoxiang; Liu, Xiansheng; Bi, Fengzhi; Feng, Deyou

2017-02-15

The role of fragments in restoring eutrophic lakes remains unclear despite the importance of re-establishing submerged macrophytes via fragments. This study established a manipulative experiment using different biomass fragments of Potamogeton crispus. This approach was adapted to study the reproductive capacity, nutrient removal efficiency, and algae inhibitory effect of fragments. Results showed that fragments could grow throughout a 49-day experiment by maintaining the stable photosynthesis efficiency of leaves and lengthening the stems. These floating fragments could regenerate by producing turions for the maintenance of their species. Moreover, the increasing removal efficiency of TP, TN, NH 4 + -N, and NO 3 - -N in water with the increase of fragment biomass indicates that the fragments could effectively purify water quality. Floating fragments competed with algae for nutrients, occupied a favorable ecological niche, and reduced algae biomass. They altered the structure of algae community and shifted the dominated green algae to cyanobacteria, the green algae of phytoplankton, and benthic algae. Findings imply that the postponable regulation of fragments is necessary for the ecological restoration of eutrophic lakes. Copyright © 2016 Elsevier B.V. All rights reserved.

Development and Application of a Two-Tier Multiple-Choice Diagnostic Test for High School Students' Understanding of Cell Division and Reproduction

ERIC Educational Resources Information Center

Sesli, Ertugrul; Kara, Yilmaz

2012-01-01

This study involved the development and application of a two-tier diagnostic test for measuring students' understanding of cell division and reproduction. The instrument development procedure had three general steps: defining the content boundaries of the test, collecting information on students' misconceptions, and instrument development.…

The Development of Adultoid Reproductives and Brachypterous Neotenic Reproductives From the Last Instar Nymphs in Reticulitermes labralis (Isoptera: Rhinotermitidae): A Comparative Study

PubMed Central

Su, Xiao Hong; Xue, Wei; Liu, He; Chen, Jiao Ling; Zhang, Xiao Jing; Xing, Lian Xi; Liu, Ming Hua

2015-01-01

Secondary reproductives develop primarily from nymphs. However, they have been rarely studied; in particular, the development of adultoid reproductives (AR) with floppy wings is still unclear. In this study, the change in juvenile hormone (JH) levels, vitellogenin gene expression, and oogenesis during the development of AR and brachypterous neotenic reproductives (BN) from the last instar nymphs of Reticulitermes labralis are investigated and compared. The results showed that the AR derived from the last instar nymphs by molting, and they were more similar to neotenic reproductives in morphology. In addition, the paired AR were not able to survive in the absence of workers. In R. labralis, the process of the last instar nymphs developing into AR and BN took an increase in JH level as a starting point. The JH level of the last instar nymphs molting into BN was approximately 1.5-fold higher than that of the AR. Additionally, The JHIII level of BN peaked on day 5, and that of AR peaked on day 10, which induced the onset of vitellogenesis in BN and AR, respectively. After molting, the vitellogenin gene expression levels of both BN and AR initially increased and then declined, and the expression levels in the BN were significantly higher than those in the AR. In addition, the oocytes of BN matured earlier than those of the AR, and the number of eggs laid by the BN was higher than the number laid by the AR. Our results demonstrate that, in R. labralis, the last instar nymphs can develop into AR, which are significantly different from BN in their development. PMID:26494776

Detection of quantitative trait loci affecting response to crowding stress in rainbow trout

USDA-ARS?s Scientific Manuscript database

Aquaculture environmental stressors such as handling, overcrowding, sub-optimal water quality parameters and social interactions negatively impact growth, feed intake, feed efficiency, disease resistance, flesh quality and reproductive performance in rainbow trout. To identify QTL affecting response...

Assessment of reproductive parameters in female Dwarf goat (Capra hircus) on the basis of progesterone profiles.

PubMed

Khanum, Shahnaz Adeeb; Hussain, Mujahid; Kausar, Rehana

2007-12-01

A study was undertaken to look into the reproductive performance of female Dwarf goats reared under traditional conditions at NIAB Farm, Faisalabad, Pakistan. The serum progesterone profile was used to monitor various reproductive parameters (length of postpartum period, resumption of cyclicity, gestation period, prepartum period, parturition) in two lots of goats. Litter size, birth weight of kids and kidding interval were also observed. Most of the animals conceived within 15-59 days of postpartum period. All the does conceived at first or second estrus. During gestation period, higher levels of progesterone were maintained with wide variations falling in the range of 3-13 ng ml(-1). However, a few days before parturition a decline was noticed at 6+/-0.9 days and it reached to the basal level of 0.1 ng ml(-1) after the completion of parturition process. The length of gestation period was found to be 145.8+/-5 days in the first lot and 145.2+/-4 days in the second lot. A very short kidding interval (203.7+/-46 days) and considerably bigger litter size (1.8+/-0.8) was observed. All the parturitions were normal and a considerable weight gain (8.2+/-0.3 kg) of mothers was recorded during pregnancy. The initial birth weight of kids was averaged as 2.1+/-0.5 kg in the first and 1.6+/-0.2 kg in the second lot. It was concluded that Dwarf goat has short gestation length, postpartum period and kidding interval along with multiple births being common. Due to these factors, its reproductive efficiency can be exploited for efficient goat meat production.

Sex steroid hormone determination of the maternal brain: effects beyond reproduction.

PubMed

Kinsley, C H; Meyer, E; Rafferty, K A

2012-10-01

Herein we discuss the effects of hormones on reproduction, but with a focus on the ripples that emanate from the main effects. That is, the role of hormones in reproductive events is both well-known and well accepted; less studied and understood are effects that appear to be ancillary to the primary objectives of the hormonal effects, which support, complement and extend their primary effects. We present evidence for how the hormonal stimulation of pregnancy constructs the maternal brain; makes it more efficient; enhances cognition; regulates stress responsiveness; modifies sensory systems (we discuss mainly olfaction); neurogenesis; and learning. Thus, steroid and other hormones and neuropeptides restructure the nervous system, particularly of females, to produce and regulate maternal behavior as well as behaviors and physiological systems that contribute to and support what is arguably the primary function of the hormones: survival and effective nurturance of the female's metabolic and genetic investment.

Optimal time--energy allocation and the evolution of colony demography among eusocial insects. [Polistes fuscatus, Vespa orientalis, ants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Macevicz, S.C.

1979-05-09

This thesis attempts to explain the evolution of certain features of social insect colony population structure by the use of optimization models. Two areas are examined in detail. First, the optimal reproductive strategies of annual eusocial insects are considered. A model is constructed for the growth of workers and reproductives as a function of the resources allocated to each. Next the allocation schedule is computed which yields the maximum number of reproductives by season's end. The results indicate that if there is constant return to scale for allocated resources the optimal strategy is to invest in colony growth until approximatelymore » one generation before season's end, whereupon worker production ceases and reproductive effort is switched entirely to producing queens and males. Furthermore, the results indicate that if there is decreasing return to scale for allocated resources then simultaneous production of workers and reproductives is possible. The model is used to explain the colony demography of two species of wasp, Polistes fuscatus and Vespa orientalis. Colonies of these insects undergo a sudden switch from the production of workers to the production of reproductives. The second area examined concerns optimal forager size distributions for monomorphic ant colonies. A model is constructed that describes the colony's energetic profit as a function which depends on the size distribution of food resources as well as forager efficiency, metabolic costs, and manufacturing costs.« less

[LEAFY, a master regulator of flower development].

PubMed

Vachon, Gilles; Tichtinsky, Gabrielle; Parcy, François

2012-01-01

Flowering plants or angiosperms constitute the vast majority of plant species. Their evolutionary success is largely due to the efficiency of the flower as reproductive structure. Work performed on model plant species in the last 20 years has identified the LEAFY gene as a key regulator of flower development. LEAFY is a unique plant transcription factor responsible for the formation of the earliest floral stage as well as for the induction of homeotic genes triggering floral organ determination. But LEAFY is also present in non-flowering plants such as mosses, ferns and gymnosperms. Recent studies suggest that LEAFY might play a role in cell division and meristem development in basal plants, a function that is probably more ancestral than the later acquired floral function. Analyzing the evolution of the role and the biochemical properties of this peculiar regulator starts to shade light on the mysterious origin of flowering plants. © Société de Biologie, 2012.

Genome engineering through CRISPR/Cas9 technology in the human germline and pluripotent stem cells.

PubMed

Vassena, R; Heindryckx, B; Peco, R; Pennings, G; Raya, A; Sermon, K; Veiga, A

2016-06-01

With the recent development of CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 genome editing technology, the possibility to genetically manipulate the human germline (gametes and embryos) has become a distinct technical possibility. Although many technical challenges still need to be overcome in order to achieve adequate efficiency and precision of the technology in human embryos, the path leading to genome editing has never been simpler, more affordable, and widespread. In this narrative review we seek to understand the possible impact of CRISR/Cas9 technology on human reproduction from the technical and ethical point of view, and suggest a course of action for the scientific community. This non-systematic review was carried out using Medline articles in English, as well as technical documents from the Human Fertilisation and Embryology Authority and reports in the media. The technical possibilities of the CRISPR/Cas9 technology with regard to human reproduction are analysed based on results obtained in model systems such as large animals and laboratory rodents. Further, the possibility of CRISPR/Cas9 use in the context of human reproduction, to modify embryos, germline cells, and pluripotent stem cells is reviewed based on the authors' expert opinion. Finally, the possible uses and consequences of CRISPR/cas9 gene editing in reproduction are analysed from the ethical point of view. We identify critical technical and ethical issues that should deter from employing CRISPR/Cas9 based technologies in human reproduction until they are clarified. Overcoming the numerous technical limitations currently associated with CRISPR/Cas9 mediated editing of the human germline will depend on intensive research that needs to be transparent and widely disseminated. Rather than a call to a generalized moratorium, or banning, of this type of research, efforts should be placed on establishing an open, international, collaborative and regulated research framework. Equally important, a societal discussion on the risks, benefits, and preferred applications of the new technology, including all relevant stakeholders, is urgently needed and should be promoted, and ultimately guide research priorities in this area. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Resource partitioning to male and female flowers of Spinacia oleracea L. in relation to whole-plant monocarpic senescence

PubMed Central

Sklensky, Diane E.; Davies, Peter J.

2011-01-01

Male plants of spinach (Spinacea oleracea L.) senesce following flowering. It has been suggested that nutrient drain by male flowers is insufficient to trigger senescence. The partitioning of radiolabelled photosynthate between vegetative and reproductive tissue was compared in male (staminate) versus female (pistillate) plants. After the start of flowering staminate plants senesce 3 weeks earlier than pistillate plants. Soon after the start of flowering, staminate plants allocated several times as much photosynthate to flowering structures as did pistillate plants. The buds of staminate flowers with developing pollen had the greatest draw of photosynthate. When the staminate plants begin to show senescence 68% of fixed C was allocated to the staminate reproductive structures. In the pistillate plants, export to the developing fruits and young flowers remained near 10% until mid-reproductive development, when it increased to 40%, declining to 27% as the plants started to senesce. These differences were also present on a sink-mass corrected basis. Flowers on staminate spinach plants develop faster than pistillate flowers and have a greater draw of photosynthate than do pistillate flowers and fruits, although for a shorter period. Pistillate plants also produce more leaf area within the inflorescence to sustain the developing fruits. The 14C in the staminate flowers declined due to respiration, especially during pollen maturation; no such loss occurred in pistillate reproductive structures. The partitioning to the reproductive structures correlates with the greater production of floral versus vegetative tissue in staminate plants and their more rapid senescence. As at senescence the leaves still had adequate carbohydrate, the resources are clearly phloem-transported compounds other than carbohydrates. The extent of the resource redistribution to reproductive structures and away from the development of new vegetative sinks, starting very early in the reproductive phase, is sufficient to account for the triggering of senescence in the rest of the plant. PMID:21565983

Normal development of the female reproductive system

EPA Science Inventory

The embryonic development of the female reproductive system involves a progression of events that is conserved across vertebrate species. The early gonad progresses from a form that is undifferentiated in both genotypic males and females. Rudimentary male (Wolffian) and female (M...

Reproductive Management for Optimal Oocyte Development to Enhance Fertility

USDA-ARS?s Scientific Manuscript database

There are multiple steps associated with the ovulatory follicle that affect oocyte growth, fertilization, embryo development and establishment of pregnancy. When estrous cycles are manipulated with assisted reproductive technologies and ovulation induced, some of these variables become more importa...

Male Reproductive System

MedlinePlus

... sexual intercourse. The male reproductive system also produces sex hormones, which help a boy develop into a sexually mature man during puberty . ... Understanding Early Sexual Development Questions and Answers About Sex Talking to Your ... Torsion For Boys: Trouble "Down There" Boys and Puberty All About ...

The safe use of Doliocarpus dentatus in the gestational period: Absence of changes in maternal reproductive performance, embryo-fetal development and DNA integrity.

PubMed

Ishikawa, Raissa Borges; Vani, Juliana Miron; das Neves, Silvia Cordeiro; Rabacow, Ana Paula Maluf; Kassuya, Cândida Aparecida Leite; Croda, Júlio; Cardoso, Claudia Andrea Lima; Monreal, Antônio Carlos Duenhas Ferreira; Antoniolli, Andreia Conceição Milan Brochado; Cunha-Laura, Andréa Luiza; Oliveira, Rodrigo Juliano

2018-05-10

Doliocarpus dentatus (Dilleniaceae) is commonly used in Brazil for the treatment of inflammatory process pain and urinary retention. Previous studies of our group have demonstrated the anti-inflammatory and antimycobacterial action of the ethanolic extract of Doliocarpus dentatus (EEDd) as well as the safety of its use. we investigated the effects of EEDd on reproductive performance, fetal development and DNA integrity in pregnant female Swiss mice. thirty female Swiss mice were divided into three experimental groups (n = 10): control group treated with 1% tween-80 and EEDd1 and EEDd2 groups treated with EEDd at doses of 100 and 1000 mg/kg, respectively. The treatment occurred by oral gavage throughout the gestational period. At the end of pregnancy, parameters related to reproductive performance, embryofoetal development and DNA integrity was evaluated. both doses of the extract tested did not alter the reproductive parameters, did not present significant differences in the embryofetal development when compared to the control group and also did not induce the formation of micronuclei. the EEDd do not alter the reproductive parameters, embryofetal development and DNA integrity, ensuring its safe use during pregnancy. Copyright © 2018 Elsevier B.V. All rights reserved.

Androgen Receptor (AR) Physiological Roles in Male and Female Reproductive Systems: Lessons Learned from AR-Knockout Mice Lacking AR in Selective Cells1

PubMed Central

Chang, Chawnshang; Lee, Soo Ok; Wang, Ruey-Sheng; Yeh, Shuyuan; Chang, Ta-Min

2013-01-01

ABSTRACT Androgens/androgen receptor (AR) signaling is involved primarily in the development of male-specific phenotypes during embryogenesis, spermatogenesis, sexual behavior, and fertility during adult life. However, this signaling has also been shown to play an important role in development of female reproductive organs and their functions, such as ovarian folliculogenesis, embryonic implantation, and uterine and breast development. The establishment of the testicular feminization (Tfm) mouse model exploiting the X-linked Tfm mutation in mice has been a good in vivo tool for studying the human complete androgen insensitivity syndrome, but this mouse may not be the perfect in vivo model. Mouse models with various cell-specific AR knockout (ARKO) might allow us to study AR roles in individual types of cells in these male and female reproductive systems, although discrepancies are found in results between labs, probably due to using various Cre mice and/or knocking out AR in different AR domains. Nevertheless, no doubt exists that the continuous development of these ARKO mouse models and careful studies will provide information useful for understanding AR roles in reproductive systems of humans and may help us to develop more effective and more specific therapeutic approaches for reproductive system-related diseases. PMID:23782840

Development and psychometric evaluation of a women shift workers' reproductive health questionnaire: study protocol for a sequential exploratory mixed-method study.

PubMed

Nikpour, Maryam; Tirgar, Aram; Ebadi, Abbas; Ghaffari, Fatemeh; Firouzbakht, Mojgan; Hajiahmadi, Mahmod

2018-02-06

Although shift works is a certain treat for female reproductive health, but currently, there is no standardized instrument for measuring reproductive health among female shift workers. This study aims to develop and evaluate the psychometric properties of a Women Shift Workers' Reproductive Health Questionnaire (WSW-RHQ). This is a sequential exploratory mixed-method study with a qualitative and a quantitative phase. In the qualitative phase, semi-structured interviews will be held with female shift workers who live in Mazandaran Province, Iran, additionally, the literature review will be performed by searching electronic databases. Sampling will be done in different workplaces and with maximum variation respecting female shift workers' age and job and educational and different economic situation. Interview data will be analyzed using conventional content analysis and then, the primary item pool for the questionnaire will be developed. In the quantitative phase, we will evaluate the psychometric properties of the questionnaire, i.e. its face, content, construct as well as reliability via the internal consistency, stability. Finally, a scoring system will be developed for the questionnaire. The development of WSW-RHQ will facilitate the promotion and implementation of reproductive health interventions and assessment of their effectiveness. Other scholars can cross-culturally adapt and use the questionnaire according to their immediate contexts.

Primates and the evolution of long, slow life histories.

PubMed

Jones, James Holland

2011-09-27

Primates are characterized by relatively late ages at first reproduction, long lives and low fertility. Together, these traits define a life-history of reduced reproductive effort. Understanding the optimal allocation of reproductive effort, and specifically reduced reproductive effort, has been one of the key problems motivating the development of life-history theory. Because of their unusual constellation of life-history traits, primates play an important role in the continued development of life-history theory. In this review, I present the evidence for the reduced reproductive effort life histories of primates and discuss the ways that such life-history tactics are understood in contemporary theory. Such tactics are particularly consistent with the predictions of stochastic demographic models, suggesting a key role for environmental variability in the evolution of primate life histories. The tendency for primates to specialize in high-quality, high-variability food items may make them particularly susceptible to environmental variability and explains their low reproductive-effort tactics. I discuss recent applications of life-history theory to human evolution and emphasize the continuity between models used to explain peculiarities of human reproduction and senescence with the long, slow life histories of primates more generally. Copyright © 2011 Elsevier Ltd. All rights reserved.

Primates and the Evolution of Long-Slow Life Histories

PubMed Central

Jones, James Holland

2011-01-01

Summary Primates are characterized by relatively late ages at first reproduction, long lives and low fertility. Together, these traits define a life-history of reduced reproductive effort. Understanding the optimal allocation of reproductive effort, and specifically reduced reproductive effort, has been one of the key problems motivating the development of life history theory. Because of their unusual constellation of life-history traits, primates play an important role in the continued development of life history theory. In this review, I present the evidence for the reduced reproductive effort life histories of primates and discuss the ways that such life-history tactics are understood in contemporary theory. Such tactics are particularly consistent with the predictions of stochastic demographic models, suggesting a key role for environmental variability in the evolution of primate life histories. The tendency for primates to specialize in high-quality, high-variability food items may make them particularly susceptible to environmental variability and explain their low reproductive-effort tactics. I discuss recent applications of life history theory to human evolution and emphasize the continuity between models used to explain peculiarities of human reproduction and senescence with the long, slow life histories of primates more generally. PMID:21959161

Effects of Fetal Exposure to Asian Sand Dust on Development and Reproduction in Male Offspring.

PubMed

Yoshida, Seiichi; Ichinose, Takamichi; Arashidani, Keiichi; He, Miao; Takano, Hirohisa; Shibamoto, Takayuki

2016-11-23

In recent experimental studies, we reported the aggravating effects of Asian sand dust (ASD) on male reproduction in mice. However, the effects of fetal ASD exposure on male reproduction have not been investigated. The present study investigated the effects of fetal ASD exposure on reproduction in male offspring. Using pregnant CD-1 mice, ASD was administered intratracheally on days 7 and 14 of gestation, and the reproduction of male offspring was determined at 5, 10, and 15 weeks after birth. The secondary sex ratio was significantly lower in the fetal ASD-exposed mice than in the controls. Histologic examination showed partial vacuolation of seminiferous tubules in immature mice. Moreover, daily sperm production (DSP) was significantly less in the fetal ASD-exposed mice than in the controls. DSP in the fetal ASD-exposed mice was approximately 10% less than the controls at both 5 and 10 weeks. However, both the histologic changes and the DSP decrease were reversed as the mice matured. These findings suggest that ASD exposure affects both the fetal development and the reproduction of male offspring. In the future, it will be necessary to clarify the onset mechanisms of ASD-induced male fetus death and male reproductive disorders.

HIGH-THROUGHPUT CELLULAR ASSAYS FOR MODELING TOXICITY IN THE FISH REPRODUCTIVE SYSTEM

EPA Science Inventory

The most important benefit of this project is the experimental evaluation of all essential steps in the development and testing of adverse outcome pathways (AOP) for a diverse set of reproductive and non-reproductive toxicants. In contrast to human testing and the toxicity pat...

Free amino acid profiles in reproductive and rind portions of cotton fruiting bodies

USDA-ARS?s Scientific Manuscript database

Boll weevil, Anthonomus grandis grandis Boheman, nutrition, particularly in terms of amino acids found in its principle reproductive plant host (plants that enable boll weevil reproduction by supplying the nutrients and sites for development to adulthood) is not well understood. However, it is know...

Head butting as an early indicator of reproductive disinhibition in the termite zootermopsis nevadensis

USDA-ARS?s Scientific Manuscript database

In lower termites, functionally sterile larval helpers are totipotent, capable of becoming reproductively active with the loss of their colony’s king or queen. Full reproductive development may take several weeks, but initiation of this response most likely occurs shortly after colony members detect...

CHARACTERIZATION OF RESPONSES TO THE ANTIANDROGEN FLUTAMIDE IN A SHORT-TERM REPRODUCTION ASSAY WITH THE FATHEAD MINNOW

EPA Science Inventory

A short-term reproduction assay with the fathead minnow has been developed to detect chemicals with the potential to disrupt reproductive endocrine functions controlled by estrogen- and androgen-mediated pathways. The objective of this study was to characterize the responses of t...

Leucine aminopeptidase, HlLAP, from the ixodid tick Haemaphysalis longicornis, plays vital roles in the development of oocytes.

PubMed

Hatta, Takeshi; Tsuji, Naotoshi; Miyoshi, Takeharu; Islam, M Khyrul; Alim, M Abdul; Yamaji, Kayoko; Anisuzzaman; Fujisaki, Kozo

2010-06-01

Female ixodid ticks are amazing invertebrate animals which efficiently convert a large amount of nutrients derived from their ingested blood meals into eggs. Although oocyte development (vitellogenesis) in ticks is triggered by a blood meal and is assumed to be supported by nutrition derived from ovarian cells connecting oocytes, little is known about the ovarian molecules processing nutrient materials for the vitellogenesis. In this study, we have suggested a putative function of leucine aminopeptidase (HlLAP) in the ovary of parthenogenetic adult ixodid tick Haemaphysalis longicornis regarding a negative output of reproduction following disruption of HlLAP gene by RNA interference. Endogenous HlLAP was shown to be localized in the ovarian cells, including ovarian epithelial and pedicel cells which were assumed to provide nutrients for the developing oocytes. Histological studies demonstrated that a majority of immature oocytes in HlLAP gene knockdown ticks were transformed into abnormal morpho-histological oocytes with vacuolated cytoplasm and/or condensed nucleus. Taken together, a reduction of the numbers of laid eggs in the HlLAP gene knockdown ticks may be due to the degeneration of immature oocytes following deprivation of nutrients such as amino acids supplied not only by midgut HlLAP but also by the ovarian HlLAP. Regulation of the tick molecules involved in nutrient metabolism for the reproduction, including blood digestion and vitellogenesis, would help in controlling the tick population and tick-borne pathogens.

Reproductive health and access to healthcare facilities: risk factors for depression and anxiety in women with an earthquake experience

PubMed Central

2011-01-01

Background The reproductive and mental health of women contributes significantly to their overall well-being. Three of the eight Millennium Development Goals are directly related to reproductive and sexual health while mental disorders make up three of the ten leading causes of disease burden in low and middle-income countries. Among mental disorders, depression and anxiety are two of the most prevalent. In the context of slower progress in achieving Millennium Development Goals in developing countries and the ever-increasing man-made and natural disasters in these areas, it is important to understand the association between reproductive health and mental health among women with post-disaster experiences. Methods This was a cross-sectional study with a sample of 387 women of reproductive age (15-49 years) randomly selected from the October 2005 earthquake affected areas of Pakistan. Data on reproductive health was collected using the Centers for Disease Control reproductive health assessment toolkit. Depression and anxiety were measured using the Hopkins Symptom Checklist-25, while earthquake experiences were captured using the Harvard Trauma Questionnaire. The association of either depression or anxiety with socio-demographic variables, earthquake experiences, reproductive health and access to health facilities was estimated using multivariate logistic regression. Results Post-earthquake reproductive health events together with economic deprivation, lower family support and poorer access to health care facilities explained a significant proportion of differences in the experiencing of clinical levels of depression and anxiety. For instance, women losing resources for subsistence, separation from family and experiencing reproductive health events such as having a stillbirth, having had an abortion, having had abnormal vaginal discharge or having had genital ulcers, were at significant risk of depression and anxiety. Conclusion The relationship between women's post-earthquake mental health and reproductive health, socio-economic status, and health care access is complex and explained largely by the socio-cultural role of women. It is suggested that interventions that consider gender differences and that are culturally appropriate are likely to reduce the incidence. PMID:21718519

Reproductive health and access to healthcare facilities: risk factors for depression and anxiety in women with an earthquake experience.

PubMed

Anwar, Jasim; Mpofu, Elias; Matthews, Lynda R; Shadoul, Ahmed Farah; Brock, Kaye E

2011-06-30

The reproductive and mental health of women contributes significantly to their overall well-being. Three of the eight Millennium Development Goals are directly related to reproductive and sexual health while mental disorders make up three of the ten leading causes of disease burden in low and middle-income countries. Among mental disorders, depression and anxiety are two of the most prevalent. In the context of slower progress in achieving Millennium Development Goals in developing countries and the ever-increasing man-made and natural disasters in these areas, it is important to understand the association between reproductive health and mental health among women with post-disaster experiences. This was a cross-sectional study with a sample of 387 women of reproductive age (15-49 years) randomly selected from the October 2005 earthquake affected areas of Pakistan. Data on reproductive health was collected using the Centers for Disease Control reproductive health assessment toolkit. Depression and anxiety were measured using the Hopkins Symptom Checklist-25, while earthquake experiences were captured using the Harvard Trauma Questionnaire. The association of either depression or anxiety with socio-demographic variables, earthquake experiences, reproductive health and access to health facilities was estimated using multivariate logistic regression. Post-earthquake reproductive health events together with economic deprivation, lower family support and poorer access to health care facilities explained a significant proportion of differences in the experiencing of clinical levels of depression and anxiety. For instance, women losing resources for subsistence, separation from family and experiencing reproductive health events such as having a stillbirth, having had an abortion, having had abnormal vaginal discharge or having had genital ulcers, were at significant risk of depression and anxiety. The relationship between women's post-earthquake mental health and reproductive health, socio-economic status, and health care access is complex and explained largely by the socio-cultural role of women. It is suggested that interventions that consider gender differences and that are culturally appropriate are likely to reduce the incidence.

Genetic Counselors' Experiences Regarding Communication of Reproductive Risks with Autosomal Recessive Conditions found on Cancer Panels.

PubMed

Mets, Sarah; Tryon, Rebecca; Veach, Patricia McCarthy; Zierhut, Heather A

2016-04-01

The development of hereditary cancer genetic testing panels has altered genetic counseling practice. Mutations within certain genes on cancer panels pose not only a cancer risk, but also a reproductive risk for autosomal recessive conditions such as Fanconi anemia, constitutional mismatch repair deficiency syndrome, and ataxia telangiectasia. This study aimed to determine if genetic counselors discuss reproductive risks for autosomal recessive conditions associated with genes included on cancer panels, and if so, under what circumstances these risks are discussed. An on-line survey was emailed through the NSGC list-serv. The survey assessed 189 cancer genetic counselors' experiences discussing reproductive risks with patients at risk to carry a mutation or variant of uncertain significance (VUS) in a gene associated with both an autosomal dominant cancer risk and an autosomal recessive syndrome. Over half (n = 82, 55 %) reported having discussed reproductive risks; the remainder (n = 66, 45 %) had not. Genetic counselors who reported discussing reproductive risks primarily did so when patients had a positive result and were of reproductive age. Reasons for not discussing these risks included when a patient had completed childbearing or when a VUS was identified. Most counselors discussed reproductive risk after obtaining results and not during the informed consent process. There is inconsistency as to if and when the discussion of reproductive risks is taking place. The wide variation in responses suggests a need to develop professional guidelines for when and how discussions of reproductive risk for autosomal recessive conditions identified through cancer panels should occur with patients.

Shifting from clonal to sexual reproduction in aphids: physiological and developmental aspects.

PubMed

Le Trionnaire, Gaël; Hardie, Jim; Jaubert-Possamai, Stéphanie; Simon, Jean-Christophe; Tagu, Denis

2008-08-01

Developmental biology is one of the fastest growing and fascinating research fields in life sciences. Among the wide range of embryonic development, a fundamental difference exists between organisms with sexual or asexual development. Aphids are unusual organisms which display alternative pathways of sexual and asexual development, the orientation of the pathway being determined by environmental conditions. These insects offer an adapted system in which to study developmental plasticity, because a side-by-side comparison of sexual and asexual development can be made in individuals with the same genotype. In this review, we describe the developmental mechanisms that have evolved in aphids for alternative sexual and asexual reproduction. In particular, we discuss how environmental cues orientate the reproductive mode of aphids from signal perception to endocrine regulation, and propose a comparative analysis of sexual and asexual gametogenesis and embryogenesis, which has been possible due to the development of molecular methods. As a result of the recent development of genomic resources in aphids, we expect these species will permit major advances in the study of the genomic basis underlying the choice of developmental fate and multiple reproduction strategies.

From fresh heterologous oocyte donation to autologous oocyte banking.

PubMed

Stoop, D

2012-01-01

Today, oocyte donation has become well established, giving rise to thousands of children born worldwide annually. The introduction of oocyte cryopreservation through vitrification allows the introduction of egg banking, improving the efficiency and comfort of oocyte donation. Moreover, the vitrification technique can now enable autologous donation of oocytes to prevent future infertility. We evaluated fresh heterologous oocyte donation in terms of obstetrical and perinatal outcome as well as of the reproductive outcome of past donors. We then evaluated the efficiency of a closed vitrification device and its clinical applications within ART. Thirdly, we evaluated the opinion of women with regard to preventive egg freezing and the efficiency of a human oocyte in relation to age. Oocyte donation is associated with an increased risk of first trimester bleeding and pregnancy induced hypertension. Donating oocytes does not seem to increase the likelihood for a later need of fertility treatment. The chance of an oocyte to result in live birth (utilization rate) in women <37 years old remains constant with a mean of 4.47%. A significant proportion of young women would consider safeguarding their reproductive potential through egg freezing or are at least open to the idea. The introduction of efficient oocyte cryopreservation has revolutionized oocyte donation through the establishment of eggbank donation. The technique also enables women to perform autologous donation after preventive oocyte storage in order to circumvent their biological clock.

Modification of reproductive development in Arabidopsis thaliana under spaceflight conditions

NASA Technical Reports Server (NTRS)

Kuang, A.; Musgrave, M. E.; Matthews, S. W.

1996-01-01

Reproductive development in Arabidopsis thaliana (L.) Heynh. cv. Columbia plants was investigated under spaceflight conditions on shuttle mission STS-51. Plants launched just prior to initiation of the reproductive phase developed flowers and siliques during the 10-d flight. Approximately 500 flowers were produced in total by the 12 plants in both the ground control and spaceflight material, and there was no significant difference in the number of flowers in each size class. The flower buds and siliques of the spaceflight plants were not morphologically different from the ground controls. Pollen viability tests immediately post-flight using fluorescein diacetate indicated that about 35% of the pollen was viable in the spaceflight material. Light-microscopy observations on this material showed that the female gametophytes also had developed normally to maturity. However, siliques from the spaceflight plants contained empty, shrunken ovules, and no evidence of pollen transfer to stigmatic papillae was found by light microscopy immediately post-flight or by scanning electron microscopy on fixed material. Short stamen length and indehiscent anthers were observed in the spaceflight material, and a film-like substance inside the anther that connected to the tapetum appeared to restrict the release of pollen from the anthers. These observations indicate that given appropriate growing conditions, early reproductive development in A. thaliana can occur normally under spaceflight conditions. On STS-51, reproductive development aborted due to obstacles in pollination or fertilization.

From Millennium Development Goals to post-2015 sustainable development: sexual and reproductive health and rights in an evolving aid environment.

PubMed

Hill, Peter S; Huntington, Dale; Dodd, Rebecca; Buttsworth, Michael

2013-11-01

Using research from country case studies, this paper offers insights into the range of institutional and structural changes in development assistance between 2005 and 2011, and their impact on the inclusion of a sexual and reproductive health and rights agenda in national planning environments. At a global level during this period, donors supported more integrative modalities of aid - sector wide approaches, poverty reduction strategy papers, direct budgetary support - with greater use of economic frameworks in decision-making. The Millennium Development Goals brought heightened attention to maternal mortality, but at the expense of a broader sexual and reproductive health and rights agenda. Advocacy at the national planning level was not well linked to programme implementation; health officials were disadvantaged in economic arguments, and lacked financial and budgetary controls to ensure a connection between advocacy and action. With increasing competency in higher level planning processes, health officials are now refocusing the post-2015 development goals. If sexual and reproductive health and rights is to claim engagement across all its multiple elements, advocates need to link them to the key themes of sustainable development: inequalities in gender, education, growth and population, but also to urbanisation, migration, women in employment and climate change. Copyright © 2013 Reproductive Health Matters. Published by Elsevier Ltd. All rights reserved.

Switch from sexual to parthenogenetic reproduction in a zebra shark.

PubMed

Dudgeon, Christine L; Coulton, Laura; Bone, Ren; Ovenden, Jennifer R; Thomas, Severine

2017-01-16

Parthenogenesis is a natural form of asexual reproduction in which embryos develop in the absence of fertilisation. Most commonly found in plants and invertebrate organisms, an increasing number of vertebrate species have recently been reported employing this reproductive strategy. Here we use DNA genotyping to report the first demonstration of an intra-individual switch from sexual to parthenogenetic reproduction in a shark species, the zebra shark Stegostoma fasciatum. A co-housed, sexually produced daughter zebra shark also commenced parthenogenetic reproduction at the onset of maturity without any prior mating. The demonstration of parthenogenesis in these two conspecific individuals with different sexual histories provides further support that elasmobranch fishes may flexibly adapt their reproductive strategy to environmental circumstances.

Insulin: its Role in the Central Control of Reproduction

PubMed Central

Sliwowska, Joanna H.; Fergani, Chrysanthi; Gawałek, Monika; Skowronska, Bogda; Fichna, Piotr; Lehman, Michael N.

2014-01-01

Insulin has long been recognized as a key regulator of energy homeostasis via its actions at the level of the brain, but in addition, plays a role in regulating neural control of reproduction. In this review, we consider and compare evidence from animal models demonstrating a role for insulin for physiological control of reproduction by effects on GnRH/LH secretion. We also review the role that insulin plays in prenatal programming of adult reproduction, and consider specific candidate neurons in the adult hypothalamus by which insulin may act to regulate reproductive function. Finally, we review clinical evidence of the role that insulin may play in adult human fertility and reproductive disorders. Overall, while insulin appears to have a significant impact on reproductive neuroendocrine function, there are many unanswered questions regarding its precise sites and mechanisms of action, and their impact on developing and adult reproductive neuroendocrine function. PMID:24874777

Insulin: its role in the central control of reproduction.

PubMed

Sliwowska, Joanna H; Fergani, Chrysanthi; Gawałek, Monika; Skowronska, Bogda; Fichna, Piotr; Lehman, Michael N

2014-06-22

Insulin has long been recognized as a key regulator of energy homeostasis via its actions at the level of the brain, but in addition, plays a role in regulating neural control of reproduction. In this review, we consider and compare evidence from animal models demonstrating a role for insulin for physiological control of reproduction by effects on GnRH/LH secretion. We also review the role that insulin plays in prenatal programming of adult reproduction, and consider specific candidate neurons in the adult hypothalamus by which insulin may act to regulate reproductive function. Finally, we review clinical evidence of the role that insulin may play in adult human fertility and reproductive disorders. Overall, while insulin appears to have a significant impact on reproductive neuroendocrine function, there are many unanswered questions regarding its precise sites and mechanisms of action, and their impact on developing and adult reproductive neuroendocrine function. Copyright © 2014 Elsevier Inc. All rights reserved.

Physical and hormonal examination of Missouri River shovelnose sturgeon reproductive stage: A reference guide

USGS Publications Warehouse

Wildhaber, M.L.; Papoulias, D.M.; DeLonay, A.J.; Tillitt, D.E.; Bryan, J.L.; Annis, M.L.

2007-01-01

From May 2001 to June 2002 Wildhaber et al. (2005) conducted monthly sampling of Lower Missouri River shovelnose sturgeon (Scaphirhynchus platorynchus) to develop methods for determination of sex and the reproductive stage of sturgeons in the field. Shovelnose sturgeon were collected from the Missouri River and ultrasonic and endoscopic imagery and blood and gonadal tissue samples were taken. The full set of data was used to develop monthly reproductive stage profiles for S. platorynchus that could be compared to data collected on pallid sturgeon (Scaphirhynchus albus). This paper presents a comprehensive reference set of images, sex steroids, and vitellogenin (VTG, an egg protein precursor) data for assessing shovelnose sturgeon sex and reproductive stage. This reference set includes ultrasonic, endoscopic, histologic, and internal images of male and female gonads of shovelnose sturgeon at each reproductive stage along with complementary data on average 17-β estradiol, 11-ketotestosterone, VTG, gonadosomatic index, and polarization index.

Sheep models of polycystic ovary syndrome phenotype

PubMed Central

Veiga-Lopez, Almudena

2012-01-01

Polycystic ovary syndrome (PCOS) is a fertility disorder affecting 5–7% of reproductive-aged women. Women with PCOS manifest both reproductive and metabolic defects. Several animal models have evolved, which implicate excess steroid exposure during fetal life in the development of the PCOS phenotype. This review addresses the fetal and adult reproductive and metabolic consequences of prenatal steroid excess in sheep and the translational relevance of these findings to PCOS. By comparing findings in various breeds of sheep, the review targets the role of genetic susceptibility to fetal insults. Disruptions induced by prenatal testosterone excess are evident at both the reproductive and metabolic level with each influencing the other thus creating a self-perpetuating vicious cycle. The review highlights the need for identifying a common mediator of the dysfunctions at the reproductive and metabolic levels and developing prevention and treatment interventions targeting all sites of disruption in unison for achieving optimal success. PMID:23084976

Zika Virus in the Male Reproductive Tract.

PubMed

Stassen, Liesel; Armitage, Charles W; van der Heide, David J; Beagley, Kenneth W; Frentiu, Francesca D

2018-04-16

Arthropod-borne viruses (arboviruses) are resurging across the globe. Zika virus (ZIKV) has caused significant concern in recent years because it can lead to congenital malformations in babies and Guillain-Barré syndrome in adults. Unlike other arboviruses, ZIKV can be sexually transmitted and may persist in the male reproductive tract. There is limited information regarding the impact of ZIKV on male reproductive health and fertility. Understanding the mechanisms that underlie persistent ZIKV infections in men is critical to developing effective vaccines and therapies. Mouse and macaque models have begun to unravel the pathogenesis of ZIKV infection in the male reproductive tract, with the testes and prostate gland implicated as potential reservoirs for persistent ZIKV infection. Here, we summarize current knowledge regarding the pathogenesis of ZIKV in the male reproductive tract, the development of animal models to study ZIKV infection at this site, and prospects for vaccines and therapeutics against persistent ZIKV infection.

ADVERSE EFFECTS OF ENVIRONMENTAL ANTIANDROGENS AND ANDROGENS ON REPRODUCTIVE DEVELOPMENT IN MAMMALS

EPA Science Inventory

Within the last decade, several classes of chemicals have been shown in laboratory studies to disrupt reproductive development by acting as androgen receptor (AR) antagonists and/or inhibitors of fetal Leydig cell testosterone production. Some phthalate esters alter gubernacular...

Developing a High Level Data Base to Teach Reproductive Endocrinology Using the HyperCard Program.

ERIC Educational Resources Information Center

Friedler, Yael; Shabo, Amnon

1990-01-01

Describes a database courseware using the HyperCard program on the subject of human reproductive endocrinology and feedback mechanisms. Discusses some issues concerning database courseware development. Presents several examples of the courseware display. (Author/YP)

GENE-ENVIRONMENT INTERACTIONS: A REVIEW OF EFFECTS ON REPRODUCTION AND DEVELOPMENT

EPA Science Inventory

Polymorphisms in genes can lead to differences in the level of susceptibility of individuals to potentially adverse effects of environmental influences, such as chemical exposure, on prenatal development or male or female reproductive function. We have reviewed the literature in ...

Paying for family planning.

PubMed

Lande, R E; Geller, J S

1991-11-01

This report discusses the challenges and costs involved in meeting the future needs for family planning in developing countries. Estimates of current expenditures for family planning go as high as $4.5 billion. According to a UNFPA report, developing country governments contribute 75% of the payments for family planning, with donor agencies contributing 15%, and users paying for 10%. Although current expenditures cover the needs of about 315 million couples of reproductive age in developing countries, this number of couples accounts for only 44% of all married women of reproductive age. Meeting all current contraceptive needs would require an additional $1 to $1.4 billion. By the year 2000, as many as 600 million couples could require family planning, costing as much as $11 billion a year. While the brunt of the responsibility for covering these costs will remain in the hand of governments and donor agencies (governments spend only 0.4% of their total budget on family planning and only 1% of all development assistance goes towards family planning), a wide array of approaches can be utilized to help meet costs. The report provides detailed discussions on the following approaches: 1) retail sales and fee-for-services providers, which involves an expanded role for the commercial sector and an increased emphasis on marketing; 2) 3rd-party coverage, which means paying for family planning service through social security institutions, insurance plans, etc.; 3) public-private collaboration (social marketing, employment-based services, etc.); 4) cost recovery, such as instituting fees in public and private nonprofit family planning clinics; and 5) improvements in efficiency.

Herbivore-mediated ecological costs of reproduction shape the life history of an iteroparous plant.

PubMed

Miller, Tom E X; Tenhumberg, Brigitte; Louda, Svata M

2008-02-01

Plant reproduction yields immediate fitness benefits but can be costly in terms of survival, growth, and future fecundity. Life-history theory posits that reproductive strategies are shaped by trade-offs between current and future fitness that result from these direct costs of reproduction. Plant reproduction may also incur indirect ecological costs if it increases susceptibility to herbivores. Yet ecological costs of reproduction have received little empirical attention and remain poorly integrated into life-history theory. Here, we provide evidence for herbivore-mediated ecological costs of reproduction, and we develop theory to examine how these costs influence plant life-history strategies. Field experiments with an iteroparous cactus (Opuntia imbricata) indicated that greater reproductive effort (proportion of meristems allocated to reproduction) led to greater attack by a cactus-feeding insect (Narnia pallidicornis) and that damage by this herbivore reduced reproductive success. A dynamic programming model predicted strongly divergent optimal reproductive strategies when ecological costs were included, compared with when these costs were ignored. Meristem allocation by cacti in the field matched the optimal strategy expected under ecological costs of reproduction. The results indicate that plant reproductive allocation can strongly influence the intensity of interactions with herbivores and that associated ecological costs can play an important selective role in the evolution of plant life histories.

Short term post-partum heat stress in dairy cows

NASA Astrophysics Data System (ADS)

Fuquay, J. W.; Chapin, L. T.; Brown, W. H.

1980-06-01

Since many dairy cows calve during late summer, the objective was to determine if heat stress immediately post-partum would (1) alter metabolism, thus, increasing susceptibility to metabolic disorders, (2) affect lactation and/or (3) affect reproduction. Forty four cows, calving during late summer, were paired with one member of each pair stressed (HS) for the first 10 post-partum days in a hot barn. Controls (CC) were kept in a cooled section of the barn. Plasma drawn weekly for 7 weeks was analyzed in an autoanalyzer for calcium, inor. phosphorus, protein, glucose and cholesterol and by radioimmunoassay for cortisol and progesterone. Ovaries and uteri were palpated weekly. Rectal temperatures were significant higher for HS during the first 10 post-partum days. No significant effects on plasma constituents were observed during the 10-day treatment period. For the 7-week period, glucose and cholesterol were lower in HS, as were cyclic peaks of progesterone and cortisol. Both calcium and inorganic phosphorus remained clinically low for the 7 weeks, but no treatment effects were seen. Uteri of HS involuted more rapidly than the CC. Treatment did not affect reproductive efficiency. Lactation milk yields did not differ, but milk fat percent was lower in HS. Heat stress immediately post-partum altered lipid metabolism, but the animal's compensatory mechanisms prevented reduction in milk production or reproductive efficiency.

State-dependent physiological maintenance in a long-lived ectotherm, the painted turtle (Chrysemys picta).

PubMed

Schwanz, Lisa; Warner, Daniel A; McGaugh, Suzanne; Di Terlizzi, Roberta; Bronikowski, Anne

2011-01-01

Energy allocation among somatic maintenance, reproduction and growth varies not only among species, but among individuals according to states such as age, sex and season. Little research has been conducted on the somatic (physiological) maintenance of long-lived organisms, particularly ectotherms such as reptiles. In this study, we examined sex differences and age- and season-related variation in immune function and DNA repair efficiency in a long-lived reptile, the painted turtle (Chrysemys picta). Immune components tended to be depressed during hibernation, in winter, compared with autumn or spring. Increased heterophil count during hibernation provided the only support for winter immunoenhancement. In juvenile and adult turtles, we found little evidence for senescence in physiological maintenance, consistent with predictions for long-lived organisms. Among immune components, swelling in response to phytohemagglutinin (PHA) and control injection increased with age, whereas basophil count decreased with age. Hatchling turtles had reduced basophil counts and natural antibodies, indicative of an immature immune system, but demonstrated higher DNA repair efficiency than older turtles. Reproductively mature turtles had reduced lymphocytes compared with juvenile turtles in the spring, presumably driven by a trade-off between maintenance and reproduction. Sex had little influence on physiological maintenance. These results suggest that components of physiological maintenance are modulated differentially according to individual state and highlight the need for more research on the multiple components of physiological maintenance in animals of variable states.

HT-COMET: a novel automated approach for high throughput assessment of human sperm chromatin quality.

PubMed

Albert, Océane; Reintsch, Wolfgang E; Chan, Peter; Robaire, Bernard

2016-05-01

Can we make the comet assay (single-cell gel electrophoresis) for human sperm a more accurate and informative high throughput assay? We developed a standardized automated high throughput comet (HT-COMET) assay for human sperm that improves its accuracy and efficiency, and could be of prognostic value to patients in the fertility clinic. The comet assay involves the collection of data on sperm DNA damage at the level of the single cell, allowing the use of samples from severe oligozoospermic patients. However, this makes comet scoring a low throughput procedure that renders large cohort analyses tedious. Furthermore, the comet assay comes with an inherent vulnerability to variability. Our objective is to develop an automated high throughput comet assay for human sperm that will increase both its accuracy and efficiency. The study comprised two distinct components: a HT-COMET technical optimization section based on control versus DNAse treatment analyses ( ITALIC! n = 3-5), and a cross-sectional study on 123 men presenting to a reproductive center with sperm concentrations categorized as severe oligozoospermia, oligozoospermia or normozoospermia. Sperm chromatin quality was measured using the comet assay: on classic 2-well slides for software comparison; on 96-well slides for HT-COMET optimization; after exposure to various concentrations of a damage-inducing agent, DNAse, using HT-COMET; on 123 subjects with different sperm concentrations using HT-COMET. Data from the 123 subjects were correlated to classic semen quality parameters and plotted as single-cell data in individual DNA damage profiles. We have developed a standard automated HT-COMET procedure for human sperm. It includes automated scoring of comets by a fully integrated high content screening setup that compares well with the most commonly used semi-manual analysis software. Using this method, a cross-sectional study on 123 men showed no significant correlation between sperm concentration and sperm DNA damage, confirming the existence of hidden chromatin damage in men with apparently normal semen characteristics, and a significant correlation between percentage DNA in the tail and percentage of progressively motile spermatozoa. Finally, the use of DNA damage profiles helped to distinguish subjects between and within sperm concentration categories, and allowed a determination of the proportion of highly damaged cells. The main limitations of the HT-COMET are the high, yet indispensable, investment in an automated liquid handling system and heating block to ensure accuracy, and the availability of an automated plate reading microscope and analysis software. This standardized HT-COMET assay offers many advantages, including higher accuracy and evenness due to automation of sensitive steps, a 14.4-fold increase in sample analysis capacity, and an imaging and scoring time of 1 min/well. Overall, HT-COMET offers a decrease in total experimental time of more than 90%. Hence, this assay constitutes a more efficient option to assess sperm chromatin quality, paves the way to using this assay to screen large cohorts, and holds prognostic value for infertile patients. Funded by the CIHR Institute of Human Development, Child and Youth Health (IHDCYH; RHF 100625). O.A. is a fellow supported by the Fonds de la Recherche du Québec - Santé (FRQS) and the CIHR Training Program in Reproduction, Early Development, and the Impact on Health (REDIH). B.R. is a James McGill Professor. The authors declare no conflicts of interest. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Marx, Irigaray, and the politics of reproduction.

PubMed

Weinbaum, A E

1994-01-01

Both the concept and practice of reproduction have been newly configured, with reproductive labor assuming an abstract value as social labor and women around the globe work to produce baby commodities which enter the market along with other domestic and imported products. This situation dictates that surrogacy not be treated as an aberration. One must instead reconceptualize the maternal body as a reproductive resource and rethink the relationship between mother and fetus. This paper attempts to develop a materialist analysis of reproductive labor by offering a strategy for renarrativizing the mother. It briefly explains what feminists involved in the pro-abortion movement could gain by incorporating a Marxist understanding of reproductive labor as productive in the strictest sense, and then suggests, through an analysis of the work of Luce Irigaray, the simultaneous need for a self-reflexive renarrativization of the maternal body which may account for women's role as reproductive laborers. Sections are on reproduction, maternal as mimetic matrix, and reproductive ethics and sexual rights.

Impact of Marine Drugs on Animal Reproductive Processes

PubMed Central

Silvestre, Francesco; Tosti, Elisabetta

2009-01-01

The discovery and description of bioactive substances from natural sources has been a research topic for the last 50 years. In this respect, marine animals have been used to extract many new compounds exerting different actions. Reproduction is a complex process whose main steps are the production and maturation of gametes, their activation, the fertilisation and the beginning of development. In the literature it has been shown that many substances extracted from marine organisms may have profound influence on the reproductive behaviour, function and reproductive strategies and survival of species. However, despite the central importance of reproduction and thus the maintenance of species, there are still few studies on how reproductive mechanisms are impacted by marine bioactive drugs. At present, studies in either marine and terrestrial animals have been particularly important in identifying what specific fine reproductive mechanisms are affected by marine-derived substances. In this review we describe the main steps of the biology of reproduction and the impact of substances from marine environment and organisms on the reproductive processes. PMID:20098597

Color reproduction for advanced manufacture of soft tissue prostheses.

PubMed

Xiao, Kaida; Zardawi, Faraedon; van Noort, Richard; Yates, Julian M

2013-11-01

The objectives of this study were to develop a color reproduction system in advanced manufacture technology for accurate and automatic processing of soft tissue prostheses. The manufacturing protocol was defined to effectively and consistently produce soft tissue prostheses using a 3D printing system. Within this protocol printer color profiles were developed using a number of mathematical models for the proposed 3D color printing system based on 240 training colors. On this basis, the color reproduction system was established and their system errors including accuracy of color reproduction, performance of color repeatability and color gamut were evaluated using 14 known human skin shades. The printer color profile developed using the third-order polynomial regression based on least-square fitting provided the best model performance. The results demonstrated that by using the proposed color reproduction system, 14 different skin colors could be reproduced and excellent color reproduction performance achieved. Evaluation of the system's color repeatability revealed a demonstrable system error and this highlighted the need for regular evaluation. The color gamut for the proposed 3D printing system was simulated and it was demonstrated that the vast majority of skin colors can be reproduced with the exception of extreme dark or light skin color shades. This study demonstrated that the proposed color reproduction system can be effectively used to reproduce a range of human skin colors for application in advanced manufacture of soft tissue prostheses. Copyright © 2013 Elsevier Ltd. All rights reserved.

Thyroid hormone actions on male reproductive system of teleost fish.

PubMed

Tovo-Neto, Aldo; da Silva Rodrigues, Maira; Habibi, Hamid R; Nóbrega, Rafael Henrique

2018-04-17

Thyroid hormones (THs) play important roles in the regulation of many biological processes of vertebrates, such as growth, metabolism, morphogenesis and reproduction. An increasing number of studies have been focused on the involvement of THs in the male reproductive system of vertebrates, in particular of fish. Therefore, this mini-review aims to summarize the main findings on THs role in male reproductive system of fish, focusing on sex differentiation, testicular development and spermatogenesis. The existing data in the literature have demonstrated that THs exert their roles at the different levels of the hypothalamic-pituitary-gonadal (HPG) axis. In general a positive correlation has been shown between THs and fish reproductive status; where THs are associated with testicular development, growth and maturation. Recently, the molecular mechanisms underlying the role of THs in spermatogenesis have been unraveled in zebrafish testis. THs promote germ cell proliferation and differentiation by increasing a stimulatory growth factor of spermatogenesis produced by Sertoli cells. In addition, THs enhanced the gonadotropin-induced androgen release in zebrafish testis. Next to their functions in the adult testis, THs are involved in the gonadal sex differentiation through modulating sex-related gene expression, and testicular development via regulation of Sertoli cell proliferation. In conclusion, this mini-review showed that THs modulate the male reproductive system during the different life stages of fish. The physiological and molecular mechanisms showed a link between the thyroid and reproduction, suggesting a possibly co-evolution and interdependence of these two systems. Copyright © 2018 Elsevier Inc. All rights reserved.

Effects of elevated glucocorticoids on reproduction and development: relevance to endocrine disruptor screening.

PubMed

Witorsch, Raphael J

2016-01-01

This article reviews the influence of the hypothalamo-pituitary-adrenocortical (HPA) axis on mammalian male and female reproduction and development of offspring and its potential impact on the identification of endocrine disruptive chemicals by in vivo assays. In the adult male rat and baboon, stress suppresses testosterone secretion via a direct inhibitory effect of elevated glucocorticoids on Leydig cells. In adult female sheep, stress disrupts reproductive function via multi-stage mechanisms involving glucocorticoid-mediated suppression of LH secretion, LH action on the ovary and the action of estradiol on its target cells (e.g., uterus). While physiological concentrations of endogenous glucocorticoids are supportive of fetal development, excessive glucocorticoids in utero (i.e., maternal stress) adversely affect mammalian offspring by "programing" abnormalities that are primarily manifest postpartum. The influence of stress on reproduction and development can also be mediated by 11β-hydroxysteroid dehydrogenase (HSD), a bi-directional oxidative:reductive pathway, which governs the balance between biologically active (reduced) endogenous glucocorticoid and inactive (oxidized) metabolites. This pathway is mediated primarily by two isozymes, 11β - HSD1 (reductase) and 11β-HSD2 (oxidase) which act both in an intracrine (intracellular) and endocrine (systemic) fashion. The 11β-HSD pathway appears to play a variety of physiological roles in mammalian reproduction and development and is a target for selected xenobiotics. The effects of the HPA axis on mammalian reproduction and development are potential confounders for in vivo bioassays in rodents employed to identify endocrine disruptive chemicals. Accordingly, consideration of the impact of the HPA axis should be incorporated into the design of bioassays for evaluating endocrine disruptors.

Incorporating reproductive management of beef heifers into a veterinary practice.

PubMed

Poock, Scott E; Payne, Craig A

2013-11-01

Veterinarians play an important role in reproductive management of dairy herds across the United States; however, in many cases, their involvement in reproductive management of beef herds has been limited. The reasons for this vary; however, there are ways for veterinarians to become more actively involved in reproductive management of US beef herds. Veterinarians can have an impact on producers' profits by implementing their skills and knowledge to beef heifer development programs. This article provides an overview of the services veterinarians can provide to beef cattle producers that pertain to reproductive management of replacement beef heifers. Published by Elsevier Inc.

ATP-binding cassette transporters in reproduction: a new frontier

PubMed Central

Bloise, E.; Ortiga-Carvalho, T.M.; Reis, F.M.; Lye, S.J.; Gibb, W.; Matthews, S.G.

2016-01-01

BACKGROUND The transmembrane ATP-binding cassette (ABC) transporters actively efflux an array of clinically relevant compounds across biological barriers, and modulate biodistribution of many physiological and pharmacological factors. To date, over 48 ABC transporters have been identified and shown to be directly and indirectly involved in peri-implantation events and fetal/placental development. They efflux cholesterol, steroid hormones, vitamins, cytokines, chemokines, prostaglandins, diverse xenobiotics and environmental toxins, playing a critical role in regulating drug disposition, immunological responses and lipid trafficking, as well as preventing fetal accumulation of drugs and environmental toxins. METHODS This review examines ABC transporters as important mediators of placental barrier functions and key reproductive processes. Expression, localization and function of all identified ABC transporters were systematically reviewed using PubMed and Google Scholar websites to identify relevant studies examining ABC transporters in reproductive tissues in physiological and pathophysiological states. Only reports written in English were incorporated with no restriction on year of publication. While a major focus has been placed on the human, extensive evidence from animal studies is utilized to describe current understanding of the regulation and function of ABC transporters relevant to human reproduction. RESULTS ABC transporters are modulators of steroidogenesis, fertilization, implantation, nutrient transport and immunological responses, and function as ‘gatekeepers’ at various barrier sites (i.e. blood-testes barrier and placenta) against potentially harmful xenobiotic factors, including drugs and environmental toxins. These roles appear to be species dependent and change as a function of gestation and development. The best-described ABC transporters in reproductive tissues (primarily in the placenta) are the multidrug transporters p-glycoprotein and breast cancer-related protein, the multidrug resistance proteins 1 through 5 and the cholesterol transporters ABCA1 and ABCG1. CONCLUSIONS The ABC transporters have various roles across multiple reproductive tissues. Knowledge of efflux direction, tissue distribution, substrate specificity and regulation of the ABC transporters in the placenta and other reproductive tissues is rapidly expanding. This will allow better understanding of the disposition of specific substrates within reproductive tissues, and facilitate development of novel treatments for reproductive disorders as well as improved approaches to protecting the developing fetus. PMID:26545808

Sex-specific inhibition and stimulation of worker-reproductive transition in a termite.

PubMed

Sun, Qian; Haynes, Kenneth F; Hampton, Jordan D; Zhou, Xuguo

2017-09-06

In social insects, the postembryonic development of individuals exhibits strong phenotypic plasticity in response to the environment, thus generating the caste system. Different from eusocial Hymenoptera, in which queens dominate reproduction and inhibit worker fertility, the primary reproductive caste in termites (kings and queens) can be replaced by neotenic reproductives derived from functionally sterile individuals. Feedback regulation of nestmate differentiation into reproductives has been suggested, but the sex specificity remains inconclusive. In the eastern subterranean termite, Reticulitermes flavipes, we tested the hypothesis that neotenic reproductives regulate worker-reproductive transition in a sex-specific manner. With this R. flavipes system, we demonstrate a sex-specific regulatory mechanism with both inhibitory and stimulatory functions. Neotenics inhibit workers of the same sex from differentiating into additional reproductives but stimulate workers of the opposite sex to undergo this transition. Furthermore, this process is not affected by the presence of soldiers. Our results highlight the reproductive plasticity of termites in response to social cues and provide insights into the regulation of reproductive division of labor in a hemimetabolous social insect.

Sex-specific inhibition and stimulation of worker-reproductive transition in a termite

NASA Astrophysics Data System (ADS)

Sun, Qian; Haynes, Kenneth F.; Hampton, Jordan D.; Zhou, Xuguo

2017-10-01

In social insects, the postembryonic development of individuals exhibits strong phenotypic plasticity in response to the environment, thus generating the caste system. Different from eusocial Hymenoptera, in which queens dominate reproduction and inhibit worker fertility, the primary reproductive caste in termites (kings and queens) can be replaced by neotenic reproductives derived from functionally sterile individuals. Feedback regulation of nestmate differentiation into reproductives has been suggested, but the sex specificity remains inconclusive. In the eastern subterranean termite, Reticulitermes flavipes, we tested the hypothesis that neotenic reproductives regulate worker-reproductive transition in a sex-specific manner. With this R. flavipes system, we demonstrate a sex-specific regulatory mechanism with both inhibitory and stimulatory functions. Neotenics inhibit workers of the same sex from differentiating into additional reproductives but stimulate workers of the opposite sex to undergo this transition. Furthermore, this process is not affected by the presence of soldiers. Our results highlight the reproductive plasticity of termites in response to social cues and provide insights into the regulation of reproductive division of labor in a hemimetabolous social insect.

Deciphering structural and temporal interplays during the architectural development of mango trees.

PubMed

Dambreville, Anaëlle; Lauri, Pierre-Éric; Trottier, Catherine; Guédon, Yann; Normand, Frédéric

2013-05-01

Plant architecture is commonly defined by the adjacency of organs within the structure and their properties. Few studies consider the effect of endogenous temporal factors, namely phenological factors, on the establishment of plant architecture. This study hypothesized that, in addition to the effect of environmental factors, the observed plant architecture results from both endogenous structural and temporal components, and their interplays. Mango tree, which is characterized by strong phenological asynchronisms within and between trees and by repeated vegetative and reproductive flushes during a growing cycle, was chosen as a plant model. During two consecutive growing cycles, this study described vegetative and reproductive development of 20 trees submitted to the same environmental conditions. Four mango cultivars were considered to assess possible cultivar-specific patterns. Integrative vegetative and reproductive development models incorporating generalized linear models as components were built. These models described the occurrence, intensity, and timing of vegetative and reproductive development at the growth unit scale. This study showed significant interplays between structural and temporal components of plant architectural development at two temporal scales. Within a growing cycle, earliness of bud burst was highly and positively related to earliness of vegetative development and flowering. Between growing cycles, flowering growth units delayed vegetative development compared to growth units that did not flower. These interplays explained how vegetative and reproductive phenological asynchronisms within and between trees were generated and maintained. It is suggested that causation networks involving structural and temporal components may give rise to contrasted tree architectures.

In-vitro developmental potential of individual mouse blastomeres cultured with and without zona pellucida: future implications for human assisted reproduction.

PubMed

Illmensee, K; Kaskar, K; Zavos, P M

2006-08-01

This study was designed to compare the developmental potential of individual blastomeres derived from 2-, 4-, 6- and 8-cell mouse embryos cultured with and without zona pellucida (ZP). In the first series, one, three, five and seven blastomeres were biopsied from 2-, 4-, 6- and 8-cell embryos respectively, and inserted individually into empty ZP recipients, leaving the remaining blastomere within its original ZP. In the second series, the same protocol was used except that the biopsied blastomeres were cultured without ZP and compared with the remaining blastomere within its original ZP. For the first series, individual blastomeres derived from 2-, 4-, 6- and 8-cell embryos cultured with ZP showed blastocyst development of 82.4, 68.6, 44.4 and 23.1% respectively, with corresponding hatching rates of 70.6, 60.0, 25.9 and 7.7%. For the second series, individual blastomeres cultured without ZP progressed with blastocyst development of 73.3, 64.5, 35.7 and 22.7% respectively. Blastocyst multiplication was achieved most efficiently when using individual blastomeres from 4- and 6-cell embryos. This is the first report on comparative in-vitro propagation of single blastomeres derived from various cleavage stages in a mammalian species. Blastomere cloning with its multiple applications may be envisaged for human assisted reproductive technologies.

Selective progesterone receptor modulators in reproductive medicine: pharmacology, clinical efficacy and safety.

PubMed

Bouchard, Philippe; Chabbert-Buffet, Nathalie; Fauser, Bart C J M

2011-11-01

To discuss the mechanism of action of selective progesterone receptor modulators (SPRMs) and summarize the preclinical and clinical efficacy and safety data supporting the potential use of these compounds for gynecologic indications. Relevant publications from 2005 onward were identified using a PubMed search. Additional relevant articles were identified from citations within these publications. None. None. None. None. Mifepristone was first developed as a progesterone receptor antagonist and licensed for pregnancy termination because of the unique property of this compound to terminate pregnancy when associated with prostaglandins. Then SPRMs were developed, and among those ulipristal acetate, an efficient emergency contraceptive. Because SPRMs effectively inhibit endometrial proliferation and reduce endometriotic lesions in animal models, this suggests a possible role in the treatment of endometriosis in humans. Finally, a number of double-blind, randomized, placebo-controlled trials have demonstrated the efficacy of asoprisnil, mifepristone, telapristone acetate, and ulipristal acetate in reducing leiomyoma and uterine volume, and suppressing bleeding in women with uterine fibroids. Mifepristone in combination with prostaglandins has been licensed for pregnancy termination because of its unique ability is this area. Ulipristal acetate is available for emergency contraception. Several SPRMs hold further promise as an effective medical therapy for patients suffering from endometriosis and leiomyoma. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Consilience and Life History Theory: From Genes to Brain to Reproductive Strategy

ERIC Educational Resources Information Center

Figueredo, Aurelio Jose; Vasquez, Geneva; Brumbach, Barbara H.; Schneider, Stephanie M. R.; Sefcek, Jon A.; Tal, Ilanit R.; Hill, Dawn; Wenner, Christopher J.; Jacobs, W. Jake

2006-01-01

We describe an integrated theory of individual differences that traces the behavioral development of life history from genes to brain to reproductive strategy. We provide evidence that a single common factor, the K-Factor, underpins a variety of life-history parameters, including an assortment of sexual, reproductive, parental, familial, and…

ASSESSMENT OF A FATHEAD MINNOW REPRODUCTION ASSAY FOR IDENTIFYING ENDOCRINE-DISRUPTING CHEMICALS WITH DIVERSE MODES OF ACTION

EPA Science Inventory

The US EPA has developed a short-term reproduction test with the fathead minnow to identify potential endocrine disrupting chemicals (EDCs). The assay is initiated by collecting baseline spawning data from reproductively-active adult fathead minnows for 21 d, followed by a 21 d e...

Economic benefits of using adaptive predictive models of reproductive toxicity in the context of a tiered testing program

EPA Science Inventory

A predictive model of reproductive toxicity, as observed in rat multigeneration reproductive (MGR) studies, was previously developed using high throughput screening (HTS) data from 36 in vitro assays mapped to 8 genes or gene-sets from Phase I of USEPA ToxCast research program, t...

Asynchronous development of Honey Bee host and Varroa destructor (Mesostigmata: Varroidae) influences reproductive potential of mites

USDA-ARS?s Scientific Manuscript database

A high proportion of non-reproductive (NR) Varroa destructor, is commonly observed in honey bee colonies displaying the Varroa sensitive hygienic trait (VSH). These studies were conducted to determine the influence of brood removal and subsequent host re-invasion of Varroa mites on mite reproduction...

Toxic plants: Effects on reproduction and fetal and embryonic development in livestock

USDA-ARS?s Scientific Manuscript database

Reproductive performance not only relates to an animal’s ability to produce offspring, but to produce it at a proper time interval and provide proper neonatal care and nutrition. The recognition that poisonous plants may have a major impact on reproductive performance is relatively new and not full...

Soy protein isolate feeding does not result in reproductive toxicity in the pre-pubertal rat testis

USDA-ARS?s Scientific Manuscript database

The isoflavone phytoestrogens found in the soy protein isolate used in soy infant formulas have been shown to have estrogenic actions in the developing male reproductive tract resulting in reproductive toxicity. However, few studies have examined potential estrogenicity of soy protein isolate as opp...

ANDROGENS AND ENVIRONMENTAL ANTIANDROGENS AFFECT REPRODUCTIVE DEVELOPMENT AND PLAY BEHAVIOR IN THE SPRAGUE-DAWLEY RAT

EPA Science Inventory

Abstract: In mammals, exposure to androgens early in development is essential for masculinization of the male reproductive phenotype. Male fetuses exposed to antiandrogens during perinatal life are permanently demasculinized in their morphology and physiology, whereas exposure to...

Aflatoxin B₁-Induced Developmental and DNA Damage in Caenorhabditis elegans.

PubMed

Feng, Wei-Hong; Xue, Kathy S; Tang, Lili; Williams, Phillip L; Wang, Jia-Sheng

2016-12-26

Aflatoxin B₁ (AFB₁) is a ubiquitous mycotoxin produced by toxicogenic Aspergillus species. AFB₁ has been reported to cause serious adverse health effects, such as cancers and abnormal development and reproduction, in animals and humans. AFB₁ is also a potent genotoxic mutagen that causes DNA damage in vitro and in vivo. However, the link between DNA damage and abnormal development and reproduction is unclear. To address this issue, we examined the DNA damage, germline apoptosis, growth, and reproductive toxicity following exposure to AFB₁, using Caenorhabditis elegans as a study model. Results found that AFB₁ induced DNA damage and germline apoptosis, and significantly inhibited growth and reproduction of the nematodes in a concentration-dependent manner. Exposure to AFB₁ inhibited growth or reproduction more potently in the DNA repair-deficient xpa-1 nematodes than the wild-type N2 strain. According to the relative expression level of pathway-related genes measured by real-time PCR, the DNA damage response (DDR) pathway was found to be associated with AFB₁-induced germline apoptosis, which further played an essential role in the dysfunction of growth and reproduction in C. elegans .

Ascorbic acid supplementation partially prevents the delayed reproductive development in juvenile male rats exposed to rosuvastatin since prepuberty.

PubMed

Leite, Gabriel Adan Araújo; Figueiredo, Thamiris Moreira; Sanabria, Marciana; Dias, Ana Flávia Mota Gonçalves; Silva, Patrícia Villela E; Martins Junior, Airton da Cunha; Barbosa Junior, Fernando; Kempinas, Wilma De Grava

2017-10-01

Dyslipidemias are occurring earlier in the population due to the increase of obesity and bad eating habits. Rosuvastatin inhibits the enzyme HMG-CoA reductase, decreasing total cholesterol. Ascorbic acid is an important antioxidant compound for male reproductive system. This study aimed to evaluate whether ascorbic acid supplementation may prevent the reproductive damage provoked by rosuvastatin administration at prepuberty. Male pups were distributed into six experimental groups that received saline solution 0.9%, 3 or 10mg/kg/day of rosuvastatin, 150mg/day of ascorbic acid, or 150mg/day of ascorbic acid associated with 3 or 10mg/kg/day of rosuvastatin from post-natal day (PND) 23 until PND53. Rosuvastatin-treated groups showed delayed puberty installation, androgen depletion and impairment on testicular and epididymal morphology. Ascorbic acid partially prevented these reproductive damages. In conclusion, rosuvastatin exposure is a probable risk to reproductive development and ascorbic acid supplementation may be useful to prevent the reproductive impairment of rosuvastatin exposure. Copyright © 2017 Elsevier Inc. All rights reserved.

Infection, Reproduction Potential, and Root Galling by Root-knot Nematode Species and Concomitant Populations on Peanut and Tobacco

PubMed Central

Hirunsalee, Anan; Barker, K. R.; Beute, M. K.

1995-01-01

Single populations of Meloidogyne arenaria races 1 (MA1) and 2 (MA2) and M. hapla (MH), and mixed populations of MA1 + MA2 and MA1 + MH with four inoculum levels of eggs were tested on peanut cv. 'Florigiant' and M. incognita-resistant tobacco cv. 'McNair 373' in a greenhouse experiment. Root infection, female development, and reproduction of MA2 on peanut and MA1 on resistant tobacco were limited at 2 and 6 weeks. MA1, MH, and MA1 + MH on peanut had similar root infection (total parasitic forms per root unit) at both 2 and 6 weeks, and similar female development and reproduction potentials at 6 weeks. MA2 tended to depress root infection, female development, and reproduction of MA1 on peanut. MH had little effect on MA1 on this crop. On tobacco, MA2 population had greater incidence of root infection than did MH at 2 weeks. The two nematode species had similar development in roots at 6 weeks. All of these processes were restricted when either MA2 or MH was present together with MA1. As initial inoculum level of parasitically fit populations increased, relative infection ratio on both peanut and tobacco, and reproduction factor on peanut decreased. Populations that had high infection incidence and reproduction rates induced greater root galling than did other populations. Root galling was suppressed in the presence of antagonistic response between nematode populations. PMID:19277277

Cysteine-rich peptides (CRPs) mediate diverse aspects of cell-cell communication in plant reproduction and development.

PubMed

Marshall, Eleanor; Costa, Liliana M; Gutierrez-Marcos, Jose

2011-03-01

Cell-cell communication in plants is essential for the correct co-ordination of reproduction, growth, and development. Studies to dissect this mode of communication have previously focussed primarily on the action of plant hormones as mediators of intercellular signalling. In animals, peptide signalling is a well-documented intercellular communication system, however, relatively little is known about this system in plants. In recent years, numerous reports have emerged about small, secreted peptides controlling different aspects of plant reproduction. Interestingly, most of these peptides are cysteine-rich, and there is convincing evidence suggesting multiple roles for related cysteine-rich peptides (CRPs) as signalling factors in developmental patterning as well as during plant pathogen responses and symbiosis. In this review, we discuss how CRPs are emerging as key signalling factors in regulating multiple aspects of vegetative growth and reproductive development in plants.

Male reprotoxicity and endocrine disruption

PubMed Central

Campion, Sarah; Catlin, Natasha; Heger, Nicholas; McDonnell, Elizabeth V.; Pacheco, Sara E.; Saffarini, Camelia; Sandrof, Moses A.; Boekelheide, Kim

2013-01-01

Mammalian reproductive tract development is a tightly regulated process that can be disrupted following exposure to drugs, toxicants, endocrine disrupting chemicals or other compounds via alterations to gene and protein expression or epigenetic regulation. Indeed, the impacts of developmental exposure to certain toxicants may not be fully realized until puberty or adulthood when the reproductive tract becomes sexually mature and altered functionality is manifested. Exposures that occur later in life, once development is complete, can also disrupt the intricate hormonal and paracrine interactions responsible for adult functions, such as spermatogenesis. In this chapter, the biology and toxicology of the male reproductive tract is explored, proceeding through the various life stages including in utero development, puberty, adulthood and senescence. Special attention is given to the discussion of endocrine disrupting chemicals, chemical mixtures, low dose effects, transgenerational effects, and potential exposure-related causes of male reproductive tract cancers. PMID:22945574

Litter size influences lamb weight and ovarian reserve but not reproductive tract development or expression of genes involved in early follicular development

USDA-ARS?s Scientific Manuscript database

In ruminants, development of the female reproductive tract starts before birth, and primordial follicles in the ovaries activate during the third trimester of gestation. Lambs born as twins have lower birth weights and smaller ovarian reserves than lambs born as singletons. We hypothesized that ew...

How Effective Is Peer Education in Addressing Young People's Sexual and Reproductive Health Needs in Developing Countries?

ERIC Educational Resources Information Center

Price, Neil; Knibbs, Sarah

2009-01-01

This review article questions the assumptions at the core of peer education interventions adopted in young people's sexual and reproductive health programmes in developing countries. Peer education is a more complex and problematic approach than its popularity with development agencies and practitioners implies. Its rise to prominence is more…

Gestational bisphenol A exposure and testis development.

PubMed

Williams, Cecilia; Bondesson, Maria; Krementsov, Dimitry N; Teuscher, Cory

Virtually all humans are exposed to bisphenol A (BPA). Since BPA can act as a ligand for estrogen receptors, potential hazardous effects of BPA should be evaluated in the context of endogenous estrogenic hormones. Because estrogen is metabolized in the placenta, developing fetuses are normally exposed to very low endogenous estrogen levels. BPA, on the other hand, passes through the placenta and might have distinct adverse consequences during the sensitive stages of fetal development. Testicular gametogenesis and steroidogenesis begin early during fetal development. These processes are sensitive to estrogens and play a role in determining the number of germ stem cells, sperm count, and male hormone levels in adulthood. Although studies have shown a correlation between BPA exposure and perturbed reproduction, a clear consensus has yet to be established as to whether current human gestational BPA exposure results in direct adverse effects on male genital development and reproduction. However, studies in animals and in vitro have provided direct evidence for the ability of BPA exposure to influence male reproductive development. This review discusses the current knowledge of potential effects of BPA exposure on male reproductive health and whether gestational exposure adversely affects testis development.

[Effects of red tide microalgae Alexandrium tamarense on the life history of rotifer Brachionus plicatilis].

PubMed

Xie, Zhi-Hao; Xiao, Huh; Cai, Heng-Jiang; Wang, Ren-Jun; Tang, Xue-Xi

2007-12-01

In this paper, life-table method was used to study the effects of different concentration Alexandrium tamarense on the durations of different development stages of Brachionus plicatilis and the characters of its population growth. The results showed that A. tamarense had significant effects on the growth and development of B. plicatilis via prolonging the durations of the rotifer' s pre-reproduction and generation succession, shortening the durations of its reproduction and post-reproduction and its mean lifespan, and reducing its laying eggs and fecundity. The net reproduction rate and intrinsic increasing rate of B. plicatilis decreased significantly, in comparison with those of the control. B. plicatilis could maintain definite population increase at the presence of different concentration A. tamarense.

Reproductive Cycle of Hard Clam, Meretrix lyrata Sowerby, 1851 (Bivalvia: Veneridae) from Sarawak, Malaysia.

PubMed

Hamli, Hadi; Idris, Mohd Hanafi; Rajaee, Amy Halimah; Kamal, Abu Hena Mustafa

2015-12-01

A study of the reproductive cycle of the hard clam, Meretrix lyrata, was documented based on histological observation and Gonad Index (GI). Samples were taken from estuarine waters of the Buntal River in Sarawak, Malaysia. The gonad of M. lyrata started to develop in September 2013. Gametogenesis continued to develop until the maturation and spawning stage from February to April 2014. The GI pattern for a one-year cycle showed a significant correlation with chlorophyll a. The corresponding GI with chlorophyll a suggested that the development of the reproductive cycle of M. lyrata required a high amount of food to increase gametogenesis.

Reproductive Cycle of Hard Clam, Meretrix lyrata Sowerby, 1851 (Bivalvia: Veneridae) from Sarawak, Malaysia

PubMed Central

Hamli, Hadi; Idris, Mohd Hanafi; Rajaee, Amy Halimah; Kamal, Abu Hena Mustafa

2015-01-01

A study of the reproductive cycle of the hard clam, Meretrix lyrata, was documented based on histological observation and Gonad Index (GI). Samples were taken from estuarine waters of the Buntal River in Sarawak, Malaysia. The gonad of M. lyrata started to develop in September 2013. Gametogenesis continued to develop until the maturation and spawning stage from February to April 2014. The GI pattern for a one-year cycle showed a significant correlation with chlorophyll a. The corresponding GI with chlorophyll a suggested that the development of the reproductive cycle of M. lyrata required a high amount of food to increase gametogenesis. PMID:26868710

Identification of epitopes on nonstructural protein 7 of porcine reproductive and respiratory syndrome virus recognized by monoclonal antibodies using phage-display technology.

PubMed

Wang, Heng; Liu, Rongchang; Zhang, Weidong; Sun, Lingshuang; Ning, Zhangyong; Ji, Fangxiao; Cui, Jin; Zhang, Guihong

2017-08-01

Nonstructural protein 7 (nsp7) of porcine reproductive and respiratory syndrome virus (PRRSV) is considered to be a suitable reagent for the development of serological diagnostic assays. It can be expressed as a soluble recombinant protein in Escherichia coli, and its antibody response may continue up to 202 days post-infection. Furthermore, the region encoded by nsp7 is highly homologous among various strains within the genotype, and the results of nsp7-based enzyme-linked immunosorbent assay (ELISA) showed high agreement with previous Idexx ELISA results. All these evidences suggest the existence of important epitopes on nsp7, though the characteristics of these epitopes remain unclear. In the present study, we prepared three monoclonal antibodies against nsp7 protein and used them to screen the epitope-distribution characteristics of PRRSV nsp7 protein by phage-display technology. We identified a linear epitope NAWGDEDRLN at amino acids 153-162 type II PRRSV nsp7β subunit. This newly defined epitope showed excellent reactivity with PRSSV-positive serum samples. These results further our understanding of the antigenic structure of nsp7 protein, and provide efficient reagents for PRRSV serological tests.

Noncontact laser microsurgery of three-dimensional living objects for use in reproductive and regenerative medicine

NASA Astrophysics Data System (ADS)

Sitnikov, D. S.; Ilina, I. V.; Kosheleva, N. V.; Khramova, Yu V.; Filatov, M. A.; Semenova, M. L.; Zurina, I. M.; Gorkun, A. A.; Saburina, I. N.

2018-01-01

Laser microsurgery has enabled us to make highly precise and delicate processing of living biological specimens. We present the results of using femtosecond (fs) laser pulses in assisted reproductive technologies. Femtosecond laser dissection of outer shells of embryos (so-called laser-assisted hatching) as well as laser-mediated detachment of the desired amount of trophectoderm cells (so-called embryo biopsy) required for preimplantaion genetic diagnosis were successfully performed. The parameters of laser radiation were optimized so as to efficiently perform embryo biopsy and preserve the viability of the treated embryos. Effects of application of fs-laser radiation in the infrared (1028 nm) and visible (514 nm) wavelength ranges were studied. We also applied laser microsurgery to develop a new simple reproducible model for studying repair and regeneration in vitro. Nanosecond laser pulses were applied to perform localized microdissection of cell spheroids. After microdissection, the edges of the wound surface opened, the destruction of the initial spheroid structure was observed in the wound area, with surviving cells changing their shape into a round one. It was shown that the spheroid form partially restored in the first six hours with subsequent complete restoration within seven days due to remodeling of surviving cells.

At the crossroads of physiology and ecology: food supply and the timing of avian reproduction.

PubMed

Davies, Scott; Deviche, Pierre

2014-06-01

This article is part of a Special Issue “Energy Balance”. The decision of when to breed is crucial to the reproductive success and fitness of seasonally breeding birds. The availability of food for adults prior to breeding has long been thought to play a critical role in timing the initiation of seasonal reproductive events, in particular laying. However, unequivocal evidence for such a role remains limited and the physiological mechanisms by which an increase in food availability results in seasonal activation of the reproductive system are largely speculative. This lack of mechanistic information partly reflects a lack of integration of ecological and physiological approaches to study seasonal reproduction. Indeed, most work pertaining to the role of food availability for adults on the timing of avian reproduction has been ecological and has focused almost exclusively on female traits associated with reproductive timing (e.g., lay date and clutch size). By contrast, most work on the physiological bases of the relationship between food availability and the timing of reproduction has investigated male traits associated with reproductive development (e.g., reproductive hormones and gonadal development). To advance our understanding of these topics, we review the role of proximate factors including food availability, social factors, and ambient temperature in the control of breeding decisions, and discuss the role of three potential candidates (leptin, glucocorticoids, and GnIH-neuropeptide Y) that may mediate the effects of food availability on these decisions. We emphasize that future progress in this area is heavily contingent upon the use of physiology-based approaches and their integration into current ecological frameworks. Published by Elsevier Inc.

Review: Behavioral signs of estrus and the potential of fully automated systems for detection of estrus in dairy cattle.

PubMed

Reith, S; Hoy, S

2018-02-01

Efficient detection of estrus is a permanent challenge for successful reproductive performance in dairy cattle. In this context, comprehensive knowledge of estrus-related behaviors is fundamental to achieve optimal estrus detection rates. This review was designed to identify the characteristics of behavioral estrus as a necessary basis for developing strategies and technologies to improve the reproductive management on dairy farms. The focus is on secondary symptoms of estrus (mounting, activity, aggressive and agonistic behaviors) which seem more indicative than standing behavior. The consequences of management, housing conditions and cow- and environmental-related factors impacting expression and detection of estrus as well as their relative importance are described in order to increase efficiency and accuracy of estrus detection. As traditional estrus detection via visual observation is time-consuming and ineffective, there has been a considerable advancement of detection aids during the last 10 years. By now, a number of fully automated technologies including pressure sensing systems, activity meters, video cameras, recordings of vocalization as well as measurements of body temperature and milk progesterone concentration are available. These systems differ in many aspects regarding sustainability and efficiency as keys to their adoption for farm use. As being most practical for estrus detection a high priority - according to the current research - is given to the detection based on sensor-supported activity monitoring, especially accelerometer systems. Due to differences in individual intensity and duration of estrus multivariate analysis can support herd managers in determining the onset of estrus. Actually, there is increasing interest in investigating the potential of combining data of activity monitoring and information of several other methods, which may lead to the best results concerning sensitivity and specificity of detection. Future improvements will likely require more multivariate detection by data and systems already existing on farms.

Cytological characterization of anther development in Panax ginseng Meyer.

PubMed

Kim, Yu-Jin; Jang, Moon-Gi; Zhu, Lu; Silva, Jeniffer; Zhu, Xiaolei; Sukweenadhi, Johan; Kwon, Woo-Saeng; Yang, Deok-Chun; Zhang, Dabing

2016-07-01

Ginseng (Panax ginseng), a valued medicinal herb, is a slow-growing plant that flowers after 3 years of growth with the formation of a solitary terminal umbel inflorescence. However, little is known about cytological events during ginseng reproduction, such as the development of the male organ, the stamen. To better understand the mechanism controlling ginseng male reproductive development, here, we investigated the inflorescence and flower structure of ginseng. Moreover, we performed cytological analysis of anther morphogenesis and showed the common and specialized cytological events including the formation of four concentric cell layers surrounding male reproductive cells followed by subsequent cell differentiation and degeneration of tapetal cells, as well as the formation of mature pollen grains via meiosis and mitosis during ginseng anther development. Particularly, our transverse section and microscopic observations showed that the ginseng tapetal layer exhibits obvious nonsynchronous cell division evidenced by the observation of one or two tapetal layers frequently observed in one anther lobe, suggesting the unique control of cell division. To facilitate the future study on ginseng male reproduction, we grouped the anther development into 10 developmental stages according to the characterized cytological events.

Reproductive strategy, sexual development and attraction to facial characteristics

PubMed Central

Cornwell, R. Elisabeth; Law Smith, Miriam J; Boothroyd, Lynda G; Moore, Fhionna R; Davis, Hasker P; Stirrat, Michael; Tiddeman, Bernard; Perrett, David I

2006-01-01

Sexual reproduction strategies vary both between and within species in the level of investment in offspring. Life-history theories suggest that the rate of sexual maturation is critically linked to reproductive strategy, with high investment being associated with few offspring and delayed maturation. For humans, age of puberty and age of first sex are two developmental milestones that have been associated with reproductive strategies. Stress during early development can retard or accelerate sexual maturation and reproduction. Early age of menarche is associated with absence of younger siblings, absence of a father figure during early life and increased weight. Father absence during early life is also associated with early marriage, pregnancy and divorce. Choice of partner characteristics is critical to successful implementation of sexual strategies. It has been suggested that sexually dimorphic traits (including those evident in the face) signal high-quality immune function and reproductive status. Masculinity in males has also been associated with low investment in mate and offspring. Thus, women's reproductive strategy should be matched to the probability of male investment, hence to male masculinity. Our review leads us to predict associations between the rate of sexual maturation and adult preferences for facial characteristics (enhanced sexual dimorphism and attractiveness). We find for men, engaging in sex at an early age is related to an increased preference for feminized female faces. Similarly, for women, the earlier the age of first sex the greater the preference for masculinity in opposite-sex faces. When we controlled sexual dimorphism in male faces, the speed of sexual development in women was not associated with differences in preference for male facial attractiveness. These developmental influences on partner choice were not mediated by self-rated attractiveness or parental relationships. We conclude that individuals assort in preferences based on the rapidity of their sexual development. Fast developing individuals prefer opposite-sex partners with an increased level of sexually dimorphic facial characteristics. PMID:17118929

Reproductive strategy, sexual development and attraction to facial characteristics.

PubMed

Cornwell, R Elisabeth; Law Smith, Miriam J; Boothroyd, Lynda G; Moore, Fhionna R; Davis, Hasker P; Stirrat, Michael; Tiddeman, Bernard; Perrett, David I

2006-12-29

Sexual reproduction strategies vary both between and within species in the level of investment in offspring. Life-history theories suggest that the rate of sexual maturation is critically linked to reproductive strategy, with high investment being associated with few offspring and delayed maturation. For humans, age of puberty and age of first sex are two developmental milestones that have been associated with reproductive strategies. Stress during early development can retard or accelerate sexual maturation and reproduction. Early age of menarche is associated with absence of younger siblings, absence of a father figure during early life and increased weight. Father absence during early life is also associated with early marriage, pregnancy and divorce. Choice of partner characteristics is critical to successful implementation of sexual strategies. It has been suggested that sexually dimorphic traits (including those evident in the face) signal high-quality immune function and reproductive status. Masculinity in males has also been associated with low investment in mate and offspring. Thus, women's reproductive strategy should be matched to the probability of male investment, hence to male masculinity. Our review leads us to predict associations between the rate of sexual maturation and adult preferences for facial characteristics (enhanced sexual dimorphism and attractiveness). We find for men, engaging in sex at an early age is related to an increased preference for feminized female faces. Similarly, for women, the earlier the age of first sex the greater the preference for masculinity in opposite-sex faces. When we controlled sexual dimorphism in male faces, the speed of sexual development in women was not associated with differences in preference for male facial attractiveness. These developmental influences on partner choice were not mediated by self-rated attractiveness or parental relationships. We conclude that individuals assort in preferences based on the rapidity of their sexual development. Fast developing individuals prefer opposite-sex partners with an increased level of sexually dimorphic facial characteristics.

Automatic color preference correction for color reproduction

NASA Astrophysics Data System (ADS)

Tsukada, Masato; Funayama, Chisato; Tajima, Johji

2000-12-01

The reproduction of natural objects in color images has attracted a great deal of attention. Reproduction more pleasing colors of natural objects is one of the methods available to improve image quality. We developed an automatic color correction method to maintain preferred color reproduction for three significant categories: facial skin color, green grass and blue sky. In this method, a representative color in an object area to be corrected is automatically extracted from an input image, and a set of color correction parameters is selected depending on the representative color. The improvement in image quality for reproductions of natural image was more than 93 percent in subjective experiments. These results show the usefulness of our automatic color correction method for the reproduction of preferred colors.

Switch from sexual to parthenogenetic reproduction in a zebra shark

PubMed Central

Dudgeon, Christine L.; Coulton, Laura; Bone, Ren; Ovenden, Jennifer R.; Thomas, Severine

2017-01-01

Parthenogenesis is a natural form of asexual reproduction in which embryos develop in the absence of fertilisation. Most commonly found in plants and invertebrate organisms, an increasing number of vertebrate species have recently been reported employing this reproductive strategy. Here we use DNA genotyping to report the first demonstration of an intra-individual switch from sexual to parthenogenetic reproduction in a shark species, the zebra shark Stegostoma fasciatum. A co-housed, sexually produced daughter zebra shark also commenced parthenogenetic reproduction at the onset of maturity without any prior mating. The demonstration of parthenogenesis in these two conspecific individuals with different sexual histories provides further support that elasmobranch fishes may flexibly adapt their reproductive strategy to environmental circumstances. PMID:28091617

Growth Hormone and Reproduction: A Review of Endocrine and Autocrine/Paracrine Interactions

PubMed Central

Hull, Kerry L.; Harvey, Steve

2014-01-01

The somatotropic axis, consisting of growth hormone (GH), hepatic insulin-like growth factor I (IGF-I), and assorted releasing factors, regulates growth and body composition. Axiomatically, since optimal body composition enhances reproductive function, general somatic actions of GH modulate reproductive function. A growing body of evidence supports the hypothesis that GH also modulates reproduction directly, exerting both gonadotropin-dependent and gonadotropin-independent actions in both males and females. Moreover, recent studies indicate GH produced within reproductive tissues differs from pituitary GH in terms of secretion and action. Accordingly, GH is increasingly used as a fertility adjunct in males and females, both humans and nonhumans. This review reconsiders reproductive actions of GH in vertebrates in respect to these new conceptual developments. PMID:25580121

The potential of AOP networks for reproductive and developmental toxicity assay development

EPA Science Inventory

Historically, the prediction of reproductive and early developmental toxicity has largely relied on the use of animals. The Adverse Outcome Pathway (AOP) framework forms a basis for the development of new non-animal test methods. It also provides biological context for mechanisti...

EFFECTS OF ETHINYL ESTRADIOL ON GONDAL DEVELOPMENT AND PATHOLOGY IN CUNNER, TAUTOGOLABRUS ADSPERSUS

EPA Science Inventory

The intent of this study was to determine histopathologically the effect of ethinyl estradiol (EE2) on gonadal development, liver and kidney condition in reproductively active cunner, Tautogolabrus adspersus. Reproductively active cunner were treated by implanting EE2 in a slow r...

Simvastatin reduces fetal testosterone production and permanently alters reproductive tract development in the male rat

EPA Science Inventory

Androgen signaling by fetal Leydig cells is critical in the proper development of the male reproductive tract. As cholesterol is a precursor for hormone biosynthesis,inhibition of the cholesterol pathway during sex differentiation may reduce testosterone {T). We hypothesized tha...

The impact of sulfate restriction on seed yield and quality of winter oilseed rape depends on the ability to remobilize sulfate from vegetative tissues to reproductive organs

PubMed Central

Girondé, Alexandra; Dubousset, Lucie; Trouverie, Jacques; Etienne, Philippe; Avice, Jean-Christophe

2014-01-01

Our current knowledge about sulfur (S) management by winter oilseed rape to satisfy the S demand of developing seeds is still scarce, particularly in relation to S restriction. Our goals were to determine the physiological processes related to S use efficiency that led to maintain the seed yield and quality when S limitation occurred at the bolting or early flowering stages. To address these questions, a pulse-chase 34SO2−4 labeling method was carried out in order to study the S fluxes from uptake and remobilization at the whole plant level. In response of S limitation at the bolting or early flowering stages, the leaves are the most important source organ for S remobilization during reproductive stages. By combining 34S-tracer with biochemical fractionation in order to separate sulfate from other S-compounds, it appeared that sulfate was the main form of S remobilized in leaves at reproductive stages and that tonoplastic SULTR4-type transporters were specifically involved in the sulfate remobilisation in case of low S availability. In response to S limitation at the bolting stage, the seed yield and quality were dramatically reduced compared to control plants. These data suggest that the increase of both S remobilization from source leaves and the root proliferation in order to maximize sulfate uptake capacities, were not sufficient to maintain the seed yield and quality. When S limitation occurred at the early flowering stage, oilseed rape can optimize the mobilization of sulfate reserves from vegetative organs (leaves and stem) to satisfy the demand of seeds and maintain the seed yield and quality. Our study also revealed that the stem may act as a transient storage organ for remobilized S coming from source leaves before its utilization by seeds. The physiological traits (S remobilization, root proliferation, transient S storage in stem) observed under S limitation could be used in breeding programs to select oilseed rape genotypes with high S use efficiency. PMID:25566272

Optimization of a Host Diet for in vivo Production of Entomopathogenic Nematodes

PubMed Central

Shapiro-Ilan, David; Guadalupe Rojas, M.; Morales-Ramos, Juan A.; Louis Tedders, W.

2012-01-01

To facilitate improved in vivo culture of entomopathogenic nematodes, production of both insect hosts and nematodes should be optimized for maximum fitness, quality, and cost efficiency. In previous studies, we developed an improved diet for Tenebrio molitor, a host that is used for in vivo nematode production, and we demonstrated that single insect diet components (e.g., lipids and proteins) can have a positive or negative impact on entomopathogenic nematode fitness and quality. In this study, we tested components of our improved T. molitor diet (lipids, cholesterol, and a salt [MnSO4]) alone and in combination for effects on host susceptibility and reproductive capacity of Heterorhabditis indica and Steinernema carpocapsae. Our results indicated that moderate levels of lipids (10%) increased host susceptibility to S. carpocapsae but did not affect H. indica, whereas cholesterol and MnSO4 increased host susceptibility to H. indica but not S. carpocapsae. The combined T. molitor diet (improved for increased insect growth) increased host susceptibility to S. carpocapsae and had a neutral effect on H. indica; interactions among single diet ingredients were observed. No effects of insect host diet were detected on the reproductive capacity of either nematode species in T. molitor. Subsequently, progeny infective juveniles, derived from nematodes grown in T. molitor that were fed diets with varying nutritive components were tested for virulence to and reproduction capacity in the target pest Diaprepes abbreviatus. The progeny nematodes produced from differing T. molitor diet treatments did not differ in virulence except H. indica derived from a diet that lacked cholesterol or MnS04 (but contained lipids) did not cause significant D. abbreviatus suppression relative to the water control. We conclude that the improved insect host diet is compatible with production of H. indica and S. carpocapsae, and increases host susceptibility in S. carpocapsae. Furthermore, in a general sense, our results indicate host diets can be optimized for improved in vivo entomopathogenic nematode production efficiency. This is the first report of an insect diet that was optimized for both host and entomopathogenic nematode production. Additionally, our study indicates that host diet may impact broader aspects of entomopathogenic nematode ecology and pest control efficacy. PMID:23481558

Cluster Sampling with Referral to Improve the Efficiency of Estimating Unmet Needs among Pregnant and Postpartum Women after Disasters

PubMed Central

Horney, Jennifer; Zotti, Marianne E.; Williams, Amy; Hsia, Jason

2015-01-01

Introduction and Background Women of reproductive age, in particular women who are pregnant or fewer than 6 months postpartum, are uniquely vulnerable to the effects of natural disasters, which may create stressors for caregivers, limit access to prenatal/postpartum care, or interrupt contraception. Traditional approaches (e.g., newborn records, community surveys) to survey women of reproductive age about unmet needs may not be practical after disasters. Finding pregnant or postpartum women is especially challenging because fewer than 5% of women of reproductive age are pregnant or postpartum at any time. Methods From 2009 to 2011, we conducted three pilots of a sampling strategy that aimed to increase the proportion of pregnant and postpartum women of reproductive age who were included in postdisaster reproductive health assessments in Johnston County, North Carolina, after tornadoes, Cobb/Douglas Counties, Georgia, after flooding, and Bertie County, North Carolina, after hurricane-related flooding. Results Using this method, the percentage of pregnant and postpartum women interviewed in each pilot increased from 0.06% to 21%, 8% to 19%, and 9% to 17%, respectively. Conclusion and Discussion Two-stage cluster sampling with referral can be used to increase the proportion of pregnant and postpartum women included in a postdisaster assessment. This strategy may be a promising way to assess unmet needs of pregnant and postpartum women in disaster-affected communities. PMID:22365134

The invasiveness of Hypochaeris glabra (Asteraceae): Responses in morphological and reproductive traits for exotic populations.

PubMed

Martín-Forés, Irene; Acosta-Gallo, Belén; Castro, Isabel; de Miguel, José M; Del Pozo, Alejandro; Casado, Miguel A

2018-01-01

Scientists have been interested in many topics driven by biological invasions, such as shifts in the area of distribution of plant species and rapid evolution. Invasiveness of exotic plant species depends on variations on morphological and reproductive traits potentially associated with reproductive fitness and dispersal ability, which are expected to undergo changes during the invasion process. Numerous Asteraceae are invasive and display dimorphic fruits, resulting in a bet-hedging dispersal strategy -wind-dispersed fruits versus animal-dispersed fruits-. We explored phenotypic differentiation in seed morphology and reproductive traits of exotic (Chilean) and native (Spanish) populations of Hypochaeris glabra. We collected flower heads from five Spanish and five Chilean populations along rainfall gradients in both countries. We planted seeds from the ten populations in a common garden trial within the exotic range to explore their performance depending on the country of origin (native or exotic) and the environmental conditions at population origin (precipitation and nutrient availability). We scored plant biomass, reproductive traits and fruit dimorphism patterns. We observed a combination of bet-hedging strategy together with phenotypic differentiation. Native populations relied more on bet-hedging while exotic populations always displayed greater proportion of wind-dispersed fruits than native ones. This pattern may reflect a strategy that might entail a more efficient long distance dispersal of H. glabra seeds in the exotic range, which in turn can enhance the invasiveness of this species.

"Clean, green and ethical" animal production. Case study: reproductive efficiency in small ruminants.

PubMed

Martin, Graeme B; Kadokawa, Hiroya

2006-02-01

In response to changes in society and thus the marketplace, we need a vision for the future of our animal industries, including both on-farm and off-farm activities, that is "clean, green and ethical". Using small ruminants as a case study, we describe three "clean, green and ethical" strategies that farmers could use to improve reproductive performance. The first allows control of the timing of reproductive events by using socio-sexual signals (the "male effect") to induce synchronised ovulation in females. The second strategy, "focus feeding", is based on using short periods of nutritional supplements that are precisely timed and specifically designed for each event in the reproductive process (eg, gamete production, embryo survival, fetal programming, colostrum production). The third strategy aims to maximize offspring survival by a combination of management, nutrition and genetic selection for behaviour (temperament). All of these approaches involve non-pharmacological manipulation of the endogenous control systems of the animals and complement the detailed information from ultrasound that is now becoming available. Importantly, these approaches all have a solid foundation in reproductive biology. In several cases, they are currently used in commercial practice, but there is still room for improvement through both basic and applied research. Ultimately, these "clean, green and ethical" tools can be cost-effective, increase productivity and, at the same time, greatly improve the image of meat and milk industries in society and the marketplace.

Analgesic use in pregnancy and male reproductive development

PubMed Central

Hurtado-Gonzalez, Pablo; Mitchell, Rod T.

2017-01-01

Purpose of review Male reproductive disorders are common and increasing in incidence in many countries. Environmental factors (including pharmaceuticals) have been implicated in the development of these disorders. This review aims to summarise the emerging epidemiological and experimental evidence for a potential role of in-utero exposure to analgesics in the development of male reproductive disorders. Recent findings A number of epidemiological studies have demonstrated an association between in-utero exposure to analgesics and the development of cryptorchidism, although these findings are not consistent across all studies. Where present, these associations primarily relate to exposure during the second trimester of pregnancy. In-vivo and in-vitro experimental studies have demonstrated variable effects of exposure to analgesics on Leydig cell function in the fetal testis of rodents, particularly in terms of testosterone production. These effects frequently involve exposures that are in excess of those to which humans are exposed. Investigation of the effects of analgesics on human fetal testis have also demonstrated effects on Leydig cell function. Variation in species, model system, dosage and timing of exposure is likely to contribute to differences in the findings between studies. Summary There is increasing evidence for analgesic effects on the developing testis that have the potential to impair reproductive function. However, the importance of these findings in relation to human-relevant exposures and the risk of male reproductive disorders remains unclear. PMID:28277341

Can Reproductive Hormones Modulate Host Immunity to Breast Cancer Antigens

DTIC Science & Technology

2005-07-01

AD Award Number: W81XWH-04-1-0668 TITLE: Can Reproductive Hormones Modulate Host Immunity to Breast Cancer Antigens PRINCIPAL INVESTIGATOR: Richard T...AND SUBTITLE 5a. CONTRACT NUMBER Can Reproductive Hormones Modulate Host Immunity to Breast Cancer Antigens 5b. GRANT NUMBER W81XWH-04-!1-0668 5c...neu-N mice can be readily applied to clinical trial development. The goal of the present work is to test the hypothesis that reproductive hormones can

Pentacle gold-copper alloy nanocrystals: a new system for entering male germ cells in vitro and in vivo

NASA Astrophysics Data System (ADS)

Lin, Yu; He, Rong; Sun, Liping; Yang, Yushan; Li, Wenqing; Sun, Fei

2016-12-01

Gold-based nanocrystals have attracted considerable attention for drug delivery and biological applications due to their distinct shapes. However, overcoming biological barriers is a hard and inevitable problem, which restricts medical applications of nanomaterials in vivo. Seeking for an efficient transportation to penetrate biological barriers is a common need. There are three barriers: blood-testis barrier, blood-placenta barrier, and blood-brain barrier. Here, we pay close attention to the blood-testis barrier. We found that the pentacle gold-copper alloy nanocrystals not only could enter GC-2 cells in vitro in a short time, but also could overcome the blood-testis barrier and enter male germ cells in vivo. Furthermore, we demonstrated that the entrance efficiency would become much higher in the development stages. The results also suggested that the pentacle gold-copper alloy nanocrystals could easier enter to germ cells in the pathological condition. This system could be a new method for theranostics in the reproductive system.

Heterochrony, cannibalism, and the evolution of viviparity in Salamandra salamandra.

PubMed

Buckley, David; Alcobendas, Marina; García-París, Mario; Wake, Marvalee H

2007-01-01

The way in which novelties that lead to macroevolutionary events originate is a major question in evolutionary biology, and one that can be addressed using the fire salamander (Salamandra salamandra) as a model system. It is exceptional among amphibians in displaying intraspecific diversity of reproductive strategies. In S. salamandra, two distinct modes of reproduction co-occur: the common mode, ovoviviparity (females giving birth to many small larvae), and a phylogenetically derived reproductive strategy, viviparity (females producing only a few large, fully metamorphosed juveniles, which are nourished maternally). We examine the relationship between heterochronic modifications of the ontogeny and the evolution of the new reproductive mode in the fire salamander. The in vitro development of embryos of ovoviviparous and viviparous salamanders from fertilization to metamorphosis is compared, highlighting the key events that distinguish the two modes of reproduction. We identify the heterochronic events that, together with the intrauterine cannibalistic behavior, characterize the derived viviparous reproductive strategy. The ways in which evolutionary novelties can arise by modification of developmental programs can be studied in S. salamandra. Moreover, the variation in reproductive modes and the associated variation of sequences of development occur in neighboring, conspecific populations. Thus, S. salamandra is a unique biological system in which evolutionary developmental research questions can be addressed at the level of populations.

Laser-assisted in vitro fertilization facilitates fertilization of vitrified-warmed C57BL/6 mouse oocytes with fresh and frozen-thawed spermatozoa, producing live pups.

PubMed

Woods, Stephanie E; Qi, Peimin; Rosalia, Elizabeth; Chavarria, Tony; Discua, Allan; Mkandawire, John; Fox, James G; García, Alexis

2014-01-01

The utility of cryopreserved mouse gametes for reproduction of transgenic mice depends on development of assisted reproductive technologies, including vitrification of unfertilized mouse oocytes. Due to hardening of the zona pellucida, spermatozoa are often unable to penetrate vitrified-warmed (V-W) oocytes. Laser-assisted in vitro fertilization (LAIVF) facilitates fertilization by allowing easier penetration of spermatozoa through a perforation in the zona. We investigated the efficiency of V-W C57BL/6NTac oocytes drilled by the XYClone laser, compared to fresh oocytes. By using DAP213 for cryoprotection, 83% (1,470/1,762) of vitrified oocytes were recovered after warming and 78% were viable. Four groups were evaluated for two-cell embryo and live offspring efficiency: 1) LAIVF using V-W oocytes, 2) LAIVF using fresh oocytes, 3) conventional IVF using V-W oocytes and 4) conventional IVF using fresh oocytes. First, the groups were tested using fresh C57BL/6NTac spermatozoa (74% motile, 15 million/ml). LAIVF markedly improved the two-cell embryo efficiency using both V-W (76%, 229/298) and fresh oocytes (69%, 135/197), compared to conventional IVF (7%, 12/182; 6%, 14/235, respectively). Then, frozen-thawed C57BL/6NTac spermatozoa (35% motile, 15 million/ml) were used and LAIVF was again found to enhance fertilization efficiency, with two-cell embryo rates of 87% (298/343) using V-W oocytes (P<0.05, compared to fresh spermatozoa), and 73% (195/266) using fresh oocytes. Conventional IVF with frozen-thawed spermatozoa using V-W (6%, 10/168) and fresh (5%, 15/323) oocytes produced few two-cell embryos. Although live offspring efficiency following embryo transfer was greater with conventional IVF (35%, 18/51; LAIVF: 6%, 50/784), advantage was seen with LAIVF in live offspring obtained from total oocytes (5%, 50/1,010; conventional IVF: 2%, 18/908). Our results demonstrated that zona-drilled V-W mouse oocytes can be used for IVF procedures using both fresh and frozen-thawed spermatozoa, producing live pups. The ability to cryopreserve mouse gametes for LAIVF may facilitate management of large-scale transgenic mouse production facilities.

Review on research of suppression male fertility and male contraceptive drug development by natural products.

PubMed

Bajaj, Vijay Kumar; Gupta, Radhey S

2013-08-01

Male contraceptive development in the present scenario is most viable aspect of research due to uncontrolled population growth in the world. In this respect investigators are busy to find out a safe male contraceptive drug. Researchers have started their finding for a suitable drug from natural sources because these are safe and easily acceptable for common man, most of natural sources are plants and their products. In this review 137 plants and their effects on reproduction and reproductive physiology are summarized. Some of them have intense effect on male reproductive system and do not produce any side effects. Reproductive toxicological studies are also important aspects of these kinds of researches, so it is important that drugs are safe and widely acceptable. An ideal male contraceptive can influence semen, testes, hormone level, accessory reproductive organs and general physiology of animals and produced some alterations. Many plants in this review are showing antifertility as well as antispermatogenic effects, so these may be used for further study for contraceptives development but it is important to find out the mechanism of reaction and further laboratory and clinical research on some plants are needed for final male contraceptive drug development. In conclusion this review will help for finding suitable plant products for male contraceptive clinical and laboratory studies.

The Boron Efflux Transporter ROTTEN EAR Is Required for Maize Inflorescence Development and Fertility[C][W][OPEN

PubMed Central

Chatterjee, Mithu; Tabi, Zara; Galli, Mary; Malcomber, Simon; Buck, Amy; Muszynski, Michael; Gallavotti, Andrea

2014-01-01

Although boron has a relatively low natural abundance, it is an essential plant micronutrient. Boron deficiencies cause major crop losses in several areas of the world, affecting reproduction and yield in diverse plant species. Despite the importance of boron in crop productivity, surprisingly little is known about its effects on developing reproductive organs. We isolated a maize (Zea mays) mutant, called rotten ear (rte), that shows distinct defects in vegetative and reproductive development, eventually causing widespread sterility in its inflorescences, the tassel and the ear. Positional cloning revealed that rte encodes a membrane-localized boron efflux transporter, co-orthologous to the Arabidopsis thaliana BOR1 protein. Depending on the availability of boron in the soil, rte plants show a wide range of phenotypic defects that can be fully rescued by supplementing the soil with exogenous boric acid, indicating that rte is crucial for boron transport into aerial tissues. rte is expressed in cells surrounding the xylem in both vegetative and reproductive tissues and is required for meristem activity and organ development. We show that low boron supply to the inflorescences results in widespread defects in cell and cell wall integrity, highlighting the structural importance of boron in the formation of fully fertile reproductive organs. PMID:25035400

Metabolic control of oocyte development: linking maternal nutrition and reproductive outcomes

PubMed Central

Liu, Honglin; Gu, Xi; Boots, Christina; Moley, Kelle H.

2015-01-01

Obesity, diabetes, and related metabolic disorders are major health issues worldwide. As the epidemic of metabolic disorders continues, the associated medical comorbidities, including the detrimental impact on reproduction, increase as well. Emerging evidence suggests that the effects of maternal nutrition on reproductive outcomes are likely to be mediated, at least in part, by oocyte metabolism. Well-balanced and timed energy metabolism is critical for optimal development of oocytes. To date, much of our understanding of oocyte metabolism comes from the effects of extrinsic nutrients on oocyte maturation. In contrast, intrinsic regulation of oocyte development by metabolic enzymes, intracellular mediators, and transport systems is less characterized. Specifically, decreased acid transport proteins levels, increased glucose/lipid content and elevated reactive oxygen species in oocytes have been implicated in meiotic defects, organelle dysfunction and epigenetic alteration. Therefore, metabolic disturbances in oocytes may contribute to the diminished reproductive potential experienced by women with metabolic disorders. In-depth research is needed to further explore the underlying mechanisms. This review also discusses several approaches for metabolic analysis. Metabolomic profiling of oocytes, the surrounding granulosa cells, and follicular fluid will uncover the metabolic networks regulating oocyte development, potentially leading to the identification of oocyte quality markers and prevention of reproductive disease and poor outcomes in offspring. PMID:25280482

Multi-thread parallel algorithm for reconstructing 3D large-scale porous structures

NASA Astrophysics Data System (ADS)

Ju, Yang; Huang, Yaohui; Zheng, Jiangtao; Qian, Xu; Xie, Heping; Zhao, Xi

2017-04-01

Geomaterials inherently contain many discontinuous, multi-scale, geometrically irregular pores, forming a complex porous structure that governs their mechanical and transport properties. The development of an efficient reconstruction method for representing porous structures can significantly contribute toward providing a better understanding of the governing effects of porous structures on the properties of porous materials. In order to improve the efficiency of reconstructing large-scale porous structures, a multi-thread parallel scheme was incorporated into the simulated annealing reconstruction method. In the method, four correlation functions, which include the two-point probability function, the linear-path functions for the pore phase and the solid phase, and the fractal system function for the solid phase, were employed for better reproduction of the complex well-connected porous structures. In addition, a random sphere packing method and a self-developed pre-conditioning method were incorporated to cast the initial reconstructed model and select independent interchanging pairs for parallel multi-thread calculation, respectively. The accuracy of the proposed algorithm was evaluated by examining the similarity between the reconstructed structure and a prototype in terms of their geometrical, topological, and mechanical properties. Comparisons of the reconstruction efficiency of porous models with various scales indicated that the parallel multi-thread scheme significantly shortened the execution time for reconstruction of a large-scale well-connected porous model compared to a sequential single-thread procedure.

Development of a CRISPR-Cas9 System for Efficient Genome Editing of Candida lusitaniae.

PubMed

Norton, Emily L; Sherwood, Racquel K; Bennett, Richard J

2017-01-01

Candida lusitaniae is a member of the Candida clade that includes a diverse group of fungal species relevant to both human health and biotechnology. This species exhibits a full sexual cycle to undergo interconversion between haploid and diploid forms. C. lusitaniae is also an emerging opportunistic pathogen that can cause serious bloodstream infections in the clinic and yet has often proven to be refractory to facile genetic manipulations. In this work, we develop a clustered regularly interspaced short palindromic repeat (CRISPR) and CRISPR-associated gene 9 (Cas9) system to enable genome editing of C. lusitaniae . We demonstrate that expression of CRISPR-Cas9 components under species-specific promoters is necessary for efficient gene targeting and can be successfully applied to multiple genes in both haploid and diploid isolates. Gene deletion efficiencies with CRISPR-Cas9 were further enhanced in C. lusitaniae strains lacking the established nonhomologous end joining (NHEJ) factors Ku70 and DNA ligase 4. These results indicate that NHEJ plays an important role in directing the repair of DNA double-strand breaks (DSBs) in C. lusitaniae and that removal of this pathway increases integration of gene deletion templates by homologous recombination. The described approaches significantly enhance the ability to perform genetic studies in, and promote understanding of, this emerging human pathogen and model sexual species. IMPORTANCE The ability to perform efficient genome editing is a key development for detailed mechanistic studies of a species. Candida lusitaniae is an important member of the Candida clade and is relevant both as an emerging human pathogen and as a model for understanding mechanisms of sexual reproduction. We highlight the development of a CRISPR-Cas9 system for efficient genome manipulation in C. lusitaniae and demonstrate the importance of species-specific promoters for expression of CRISPR components. We also demonstrate that the NHEJ pathway contributes to non-template-mediated repair of DNA DSBs and that removal of this pathway enhances efficiencies of gene targeting by CRISPR-Cas9. These results therefore establish important genetic tools for further exploration of C. lusitaniae biology.

[Acceleration of Embryonic Development of Pinus sibirica Trees with a One-Year Reproductive Cycle].

PubMed

Tret'yakova, I N; Lukina, N V

2016-01-01

The study of the formation of embryonic structures in Pinus sibirica forms with a one-year reproductive cycle showed that the acceleration of the embryonic process manifested itself as a reduction of the coenocytic stage of the female gametophyte development (1.5 months instead of 1 year). The egg was not fertilized because of the asynchronous maturation of male and female gametophytes. Seeds without embryos were formed. We assumed that the acceleration of the reproductive process in Pinus sibirica was caused by a mutation in the female generative organs.

Patterns of fecal gonadal hormone metabolites in the maned wolf (Chrysocyon brachyurus).

PubMed

Songsasen, N; Rodden, M; Brown, J L; Wildt, D E

2006-10-01

Ex situ populations of maned wolves are not viable due to low reproductive efficiency. The objective of this study was to increase knowledge regarding the reproductive physiology of maned wolves to improve captive management. Fecal samples were collected 3-5 d/wk from 12 females of various reproductive age classes (young, prime breeding and aged) and reproductive histories (conceived and raised pups, conceived but lost pups, pseudo-pregnant and unpaired). Ovarian steroids were extracted from feces and assessed by enzyme immunoassay. Concentrations of estrogen metabolites gradually increased, beginning 2-5 d before breeding, and declined to baseline on the day of lordosis and copulation. Fecal progestin metabolite concentrations increased steadily during the periovulatory period, when sexual receptivity was observed, and remained elevated during pregnancy and pseudo-pregnancy. During the luteal phase, young and prime breeding-age females excreted larger amounts of progestins than those of older age classes. Furthermore, progestin concentrations were higher during the luteal phase of pregnant versus pseudo-pregnant bitches. Profiles of fecal progestin metabolites for three singleton females were unchanged throughout the breeding season, suggesting ovulation is induced in this species. However, this finding could be confounded by age, as these females were either young or aged.

Driving reproduction: RFamide peptides behind the wheel.

PubMed

Kriegsfeld, Lance J

2006-12-01

The availability of tools for probing the genome and proteome more efficiently has allowed for the rapid discovery of novel genes and peptides that play important, previously uncharacterized roles in neuroendocrine regulation. In this review, the role of a class of neuropeptides containing the C-terminal Arg-Phe-NH(2) (RFamide) in regulating the reproductive axis will be highlighted. Neuropeptides containing the C-terminal Phe-Met-Arg-Phe-NH(2) (FMRFamide) were first identified as cardioregulatory elements in the bi-valve mollusk Macrocallista nimbosa. During the past two decades, numerous studies have shown the presence of structurally similar peptides sharing the RFamide motif across taxa. In vertebrates, RFamide peptides have pronounced influences on opiatergic regulation and neuroendocrine function. Two key peptides in this family are emerging as important regulators of the reproductive axis, kisspeptin and gonadotropin-inhibitory hormone (GnIH). Kisspeptin acts as the accelerator, directly driving gonadotropin-releasing hormone (GnRH) neurons, whereas GnIH acts as the restraint. Recent evidence suggests that both peptides play a role in mediating the negative feedback effects of sex steroids. This review presents the hypothesis that these peptides share complementary roles by responding to internal and external stimuli with opposing actions to precisely regulate the reproductive axis.

Driving Reproduction: RFamide Peptides Behind the Wheel

PubMed Central

Kriegsfeld, Lance J.

2012-01-01

The availability of tools for probing the genome and proteome more efficiently has allowed for the rapid discovery of novel genes and peptides that play important, previously-uncharacterized roles in neuroendocrine regulation. In this review, the role of a class of neuropeptides containing the C-terminal Arg-Phe-NH2 (RFamide) in regulating the reproductive axis will be highlighted. Neuropeptides containing the C-terminal Phe- Met-Arg-Phe-NH2 (FMRFamide) were first identified as cardioregulatory elements in the bi-valve mollusk, Macrocallista nimbosa. During the past two decades, numerous studies have shown the presence of structurally-similar peptides sharing the RFamide motif across taxa. In vertebrates, RFamide peptides have pronounced influences on opiatergic regulation and neuroendocrine function. Two key peptides in this family are emerging as important regulators of the reproductive axis, kisspeptin and gonadotropin-inhibitory hormone (GnIH). Kisspeptin acts as the accelerator, directly driving gonadotropin-releasing hormone (GnRH) neurons, whereas GnIH acts as the restraint. Recent evidence suggests that both peptides play a role in mediating the negative feedback effects of sex steroids. This review presents the hypothesis that these peptides share complementary roles by responding to internal and external stimuli with opposing actions to precisely regulate the reproductive axis. PMID:16876801

A researcher's perceptions of United States Department of Agriculture funding in animal reproduction.

PubMed

Reeves, J J

2007-03-01

Dedicated funding for animal reproduction did not start until 1985 and was available primarily in the reproductive efficiency and physiology areas of the Animal Science Program. Funding for individual grants and duration of funding were similar between the National Institutes of Health and the USDA, typically in the range of 3 yr, with total direct costs of $150,000. The names of these programs have changed over time; the National Research Initiative Competitive Grants Program started in 1991 with a program in animal reproduction. The USDA did not change the award size for individual grants until 2001, when it gradually increased through 2003. The USDA then markedly increased individual grants in 2004 to a funding level of $300,000 to $500,000 over 3 to 4 yr. This has been beneficial for the funded scientist but discouraging to the applicants with high-ranking nonfunded grants. The number of grants funded per year is approaching a low critical number, with an average of only 10 new grants funded per year. At the present funding level it will be difficult for even the best scientist to sustain a research career based only on USDA funding.

Influence of season of birth on growth and reproductive development of Brahman bulls.

PubMed

Tatman, Shawn R; Neuendorff, Don A; Wilson, Timothy W; Randel, Ronald D

2004-07-01

Seasonal effects on reproduction are more dramatic in Bos indicus than Bos taurus cattle. This experiment evaluated reproductive development of fall- (n=7) versus spring- (n = 10) born Brahman bulls to determine if season of birth affects reproductive development. Measurements of growth and reproductive development began after weaning and continued at bi-weekly intervals until each bull reached sexual maturity. Different stages of sexual development were classified according to characteristics of the ejaculate and included first sperm in the ejaculate, puberty (> 50 x 10(6) sperm/ejaculate), and sexual maturity (two ejaculates with > 500 = 10(6) sperm/ejaculate). Average daily increases in all measured traits were similar in fall- and spring-born bulls and there were no differences in age, body weight, scrotal circumference, or paired testis volume between groups at first sperm or puberty. However, fall-born bulls were older (P < 0.05) than spring-born bulls at sexual maturity (553 days versus 481 days, respectively) as the interval between puberty and sexual maturity was longer (P < 0.05) in fall- than in spring-born bulls (82 days versus 54 days, respectively). The prolonged interval between puberty and sexual maturity in fall-born calves coincided with a short photoperiod (winter) whereas the short interval between puberty and sexual maturity in spring-born calves coincided with a long photoperiod (summer). In conclusion, season of birth affected sexual development; photoperiod might be involved in regulating testicular function immediately after puberty in Brahman bulls.

Plant Reproduction. Plant Life in Action[TM]. Schlessinger Science Library. [Videotape].

ERIC Educational Resources Information Center

2000

Plants are vital to all other life on this planet - without them, there would be no food, shelter or oxygen. Luckily, over millions of years plants have developed many different features in order to survive and reproduce. In Plant Reproduction, students will discover that primitive mosses and algae are dependent upon water for their reproduction.…

THE EFFECTS OF METHOXYCHLOR AND METHYLTESTOSTERONE ON REPRODUCTION IN A SHORT-TERM ASSAY USING THE FATHEAD MINNOW (PIMEPHALES PROMELAS)

EPA Science Inventory

The effect of chemicals on reproduction of fishes is an area of great uncertainty. Because full life cycle testing of fish is cost prohibitive, we have developed a short-term assay to assess the effects of chemicals on reproduction of adult fathead minnows (Pimephales promelas). ...

REPRODUCTIVE EFFECTS OF THE WATER DISINFECTANT BYPRODUCT BROMOCHLOROACETIC ACID (BCA) IN ADULT AND JUVENILE MALE C57BL/6 MICE

EPA Science Inventory

REPRODUCTIVE EFFECTS OF THE WATER DISINFECTANT BYPRODUCT BROMOCHLOROACETIC ACID (BCA) IN ADULT AND JUVENILE MALE C57BL/6 MICE.
JC Rockett, JC Luft, JB Garges and DJ Dix. Reproductive Toxicology Division, USEPA, RTP, NC, USA.
Sponsor: G Klinefelter
The development of wate...

Hardwood Regeneration After Seed Tree Cutting

Treesearch

Robert L. Johnson; R. M. Krinard

1976-01-01

Seed trees left at two sites did not appear to influence the establishment or development of reproduction . Seed trees were mainly sweetgum and red oaks. Most reproduction was from sprouting of the stumps and roots of cut trees or from advanced seedlings present in the understory at the time of cutting. Eighteen years after cutting, dominant trees of the reproduction...

Reproductive system, social organization, human disturbance and ecological dominance in native populations of the little fire ant, Wasmannia auropunctata.

PubMed

Foucaud, Julien; Orivel, Jérôme; Fournier, Denis; Delabie, Jacques H C; Loiseau, Anne; Le Breton, Julien; Cerdan, Philippe; Estoup, Arnaud

2009-12-01

The invasive ant species Wasmannia auropunctata displays both ecologically dominant and non-dominant populations within its native range. Three factors could theoretically explain the ecological dominance of some native populations of W. auropunctata: (i) its clonal reproductive system, through demographic and/or adaptive advantages; (ii) its unicolonial social organization, through lower intraspecific and efficient interspecific competition; (iii) the human disturbance of its native range, through the modification of biotic and abiotic environmental conditions. We used microsatellite markers and behavioural tests to uncover the reproductive modes and social organization of dominant and non-dominant native populations in natural and human-modified habitats. Microsatellite and mtDNA data indicated that dominant and non-dominant native populations (supercolonies as determined by aggression tests) of W. auropunctata did not belong to different evolutionary units. We found that the reproductive system and the social organization are neither necessary nor sufficient to explain W. auropunctata ecological dominance. Dominance rather seems to be set off by unknown ecological factors altered by human activities, as all dominant populations were recorded in human-modified habitats. The clonal reproductive system found in some populations of W. auropunctata may however indirectly contribute to its ecological dominance by allowing the species to expand its environmental niche, through the fixation over time of specific combinations of divergent male and female genotypes. Unicoloniality may rather promote the range expansion of already dominant populations than actually trigger ecological dominance. The W. auropunctata model illustrates the strong impact of human disturbance on species' ecological features and the adaptive potential of clonal reproductive systems.

Associations between management practices and major reproductive parameters of Holstein-Friesian replacement heifers.

PubMed

Fodor, I; Baumgartner, W; Abonyi-Tóth, Zs; Lang, Zs; Ózsvári, L

2018-01-01

The aim of this study was to assess the relationship between the reproductive management practices and the performance of replacement heifers on large commercial dairy farms. The individual data of 14,763 heifers, first inseminated in 2014, were analysed from 33 Holstein-Friesian dairy herds in Hungary. The relationships between management practices and major reproductive parameters (age at first service, AFS; age at first calving, AFC; conception risk to first insemination, CR1; and pregnancy status at 20 months of age) were examined by mixed-effects models, with the herd as the random effect. The results showed that farms using oestrus detection aids experienced reduced AFS (p<0.001) and AFC (p=0.001). Observation of oestrus for shorter periods instead of continuously showed a tendency towards lower AFC (p=0.057) and was associated with higher odds of pregnancy at 20 months of age (p=0.020). Heifers on farms using sexed semen had younger AFS, but poorer CR1, compared to those using conventional semen exclusively (p<0.05). In addition, the odds of heifers being pregnant by 20 months of age was higher on farms with more experience using sexed semen (p=0.020). Frequent pregnancy diagnosis (i.e. more than once per week) was associated with younger AFC (p=0.023). Our results suggest the use of certain advanced reproductive management practices for heifer reproductive management in large dairy herds (e.g. oestrus detection aids), which can improve reproductive efficiency considerably, but are currently used only to a limited extent. Copyright © 2017 Elsevier B.V. All rights reserved.

Fertility and Infertility.

ERIC Educational Resources Information Center

Orgebin-Crist, Marie-Claire; And Others

In this report, emphasis is placed on major research developments in the reproductive sciences, their impact on the health of individuals as well as on that of society, and on current trends that may provide new opportunities for future research in fertility and infertility. In the first section, major developments in the reproductive sciences are…

Youth Reproductive & Sexual Health in Nigeria

ERIC Educational Resources Information Center

Sampson, Melodi

2010-01-01

Nearly one third of Nigeria's total population of 148.1 million is between the ages of 10 and 24. Nigerian adolescents' sizeable share of the population makes them integral to the country's social, political and economic development. Nigeria's development is compromised by the sexual and reproductive health issues afflicting its youth. Lack of…

HORMONAL CONTROL OF OVARIAN FUNCTION FOLLOWING CHLOROTRIAZINE EXPOSURE: EFFECT ON REPRODUCTIVE FUNCTION AND MAMMARY GLAND TUMOR DEVELOPMENT

EPA Science Inventory

Hormonal Control of Ovarian Function Following Chlorotriazine Exposure: Effect on Reproductive Function and Mammary Gland Tumor Development.

Ralph L. Cooper, Susan C. Laws, Michael G. Narotsky, Jerome M. Goldman, and Tammy E. Stoker

Abstract
The studies review...

EFFECT OF CONAZOLE FUNGICIDES ON REPRODUCTIVE DEVELOPMENT IN THE FEMALE RAT

EPA Science Inventory

Three triazole fungicides were evaluated for effects on female rat reproductive development. Rats were exposed via feed to propiconazole (P) (100, 500, or 2500 ppm), myclobutanil (M) (100, 500, or 2000 ppm), or triadimefon (T) (100, 500, or 1800 ppm) from gestation day 6 to postn...

Self-organized amniogenesis by human pluripotent stem cells in a biomimetic implantation-like niche

NASA Astrophysics Data System (ADS)

Shao, Yue; Taniguchi, Kenichiro; Gurdziel, Katherine; Townshend, Ryan F.; Xue, Xufeng; Yong, Koh Meng Aw; Sang, Jianming; Spence, Jason R.; Gumucio, Deborah L.; Fu, Jianping

2017-04-01

Amniogenesis--the development of amnion--is a critical developmental milestone for early human embryogenesis and successful pregnancy. However, human amniogenesis is poorly understood due to limited accessibility to peri-implantation embryos and a lack of in vitro models. Here we report an efficient biomaterial system to generate human amnion-like tissue in vitro through self-organized development of human pluripotent stem cells (hPSCs) in a bioengineered niche mimicking the in vivo implantation environment. We show that biophysical niche factors act as a switch to toggle hPSC self-renewal versus amniogenesis under self-renewal-permissive biochemical conditions. We identify a unique molecular signature of hPSC-derived amnion-like cells and show that endogenously activated BMP-SMAD signalling is required for the amnion-like tissue development by hPSCs. This study unveils the self-organizing and mechanosensitive nature of human amniogenesis and establishes the first hPSC-based model for investigating peri-implantation human amnion development, thereby helping advance human embryology and reproductive medicine.

Flight performance in the altricial zebra finch: Developmental effects and reproductive consequences.

PubMed

Crino, Ondi L; Klaassen van Oorschot, Brett; Crandell, Kristen E; Breuner, Creagh W; Tobalske, Bret W

2017-04-01

The environmental conditions animals experience during development can have sustained effects on morphology, physiology, and behavior. Exposure to elevated levels of stress hormones (glucocorticoids, GCs) during development is one such condition that can have long-term effects on animal phenotype. Many of the phenotypic effects of GC exposure during development (developmental stress) appear negative. However, there is increasing evidence that developmental stress can induce adaptive phenotypic changes. This hypothesis can be tested by examining the effect of developmental stress on fitness-related traits. In birds, flight performance is an ideal metric to assess the fitness consequences of developmental stress. As fledglings, mastering takeoff is crucial to avoid bodily damage and escape predation. As adults, takeoff can contribute to mating and foraging success as well as escape and, thus, can affect both reproductive success and survival. We examined the effects of developmental stress on flight performance across life-history stages in zebra finches ( Taeniopygia guttata ). Specifically, we examined the effects of oral administration of corticosterone (CORT, the dominant avian glucocorticoid) during development on ground-reaction forces and velocity during takeoff. Additionally, we tested for associations between flight performance and reproductive success in adult male zebra finches. Developmental stress had no effect on flight performance at all ages. In contrast, brood size (an unmanipulated variable) had sustained, negative effects on takeoff performance across life-history stages with birds from small broods performing better than birds from large broods. Flight performance at 100 days posthatching predicted future reproductive success in males; the best fliers had significantly higher reproductive success. Our results demonstrate that some environmental factors experienced during development (e.g. clutch size) have stronger, more sustained effects than others (e.g. GC exposure). Additionally, our data provide the first link between flight performance and a direct measure of reproductive success.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, E.M.

Human reproduction and development is a cycle of interdependent events. Virtually all of its phases have been shown to be the primary target of one or more non-mutagenic exogenous agents. Such agents interfere with certain of the countless epigenetic or ontogenic events essential for normal completion of the cycle. Mutagens disrupt this cycle at some points, but the overwhelming majority of reproductive and developmental toxins are not mutagenic. As in all aspects of toxicology, the reproductive and developmental effects of chemicals are determined by the intrinsic nature of the chemical, the quantity of the chemical exposure, the duration of exposuremore » and the stage of the cycle at which it occurs. Signs of reproductive toxicity range from reduced fertility to spontaneous abortion. Adverse effects on the conceptus are categorized as functional deficits, developmental retardation, structural abnormality and death. One or more of these is anticipated to occur as a result of excess exposure to most chemicals. Although the degree of hazard and risk potential can be calculated in each instance, chemicals differ markedly in their ability to interfere with reproduction and/or development. Standardized methods for reproductive and developmental toxicity safety evaluation are available for detecting adverse effects upon any aspect of reproduction and development. Data currently available establish that these state-of-the-art tests conducted in laboratory animals are often highly predictive of the type of adverse effect a particular chemical will have in humans, as well as the exposure level at which it will occur. By adding a modest safety factor to the no-observed-effect-level of well-executed animal studies, safe human exposure levels can be established. 40 references.« less

Identification of a nonsense mutation in CWC15 associated with decreased reproductive efficiency in Jersey cattle

USDA-ARS?s Scientific Manuscript database

With the recent advent of genomic tools for cattle, several recessive conditions affecting fertility have been identified and selected against, such as deficiency of uridine monophosphate synthase, complex vertebral malformation, and brachyspina. The current report refines the location of a recessiv...

Physiological characterization of peanut cultivars, experimental lines and wild species for drought & heat tolerance

USDA-ARS?s Scientific Manuscript database

Peanut is an important crop grown worldwide for its nutritional value and economic significance. Although the demand for peanuts remains high, increasing drought episodes, combined with temperatures = 100°F, affect the reproductive efficiency of the crop and threaten the supply. Peanut plants are mo...

The relationship between sperm function and diet: toms are what they eat

USDA-ARS?s Scientific Manuscript database

It is well known that cryopreserved semen could be used to regenerate commercial or research poultry lines; however, fertility rates from poultry semen frozen with current methods are not reliable enough for germ-line retrieval, especially from lines with low reproductive efficiency. As part of a l...

Experience- and egg-mediated oviposition behaviour in the yellow fever mosquito Stegomyia aegypti (=Aedes aegypti)

USDA-ARS?s Scientific Manuscript database

Animals may adapt foraging behavior in variable environments using environmental information. For repeated behaviors such as feeding or reproduction, past experiences can provide this information to guide future decision-making. By changing behavior to be more efficient in an animal’s specific env...

Manure preferences and postemergence learning of two filth fly parasitoids, Spalangia cameroni and Muscidifurax raptor (Hymenoptera: Pteromalidae)

USDA-ARS?s Scientific Manuscript database

The efficiency of host-seeking behavior is a crucial determinant of the reproductive performance of female parasitoids. Initially, parasitoids may use chemical information generated from the microhabitat in which they emerge to locate hosts. Spalangia cameroni and Muscidifurax raptor are commerciall...

Nigerian lawyers and reproductive health rights: a survey of knowledge, practices and opinions on law reforms among the bar and bench in north eastern Nigeria.

PubMed

Mairiga, Abdulkarim Garba; Geidam, Ado Dan'azumi; Bako, Babagana; Ibrahim, Abdullahi

2012-03-01

The objective of this study was to determine the knowledge and attitudes of practicing Nigerian lawyers towards issues relating to reproductive health and reproductive rights, and their opinions about abortion law reform. It was a population- based study which consisted of interviews with practicing lawyers in north-east Nigeria. The results showed poor knowledge of issues related to reproductive health and reproductive rights among the lawyers. However, the majority (56.9%) disagreed that a woman can practice family planning without the consent of her husband. The prevalence of contraceptive use among the lawyers was low and attitude to abortion law not satisfactory. Only few lawyers (22.4%) supported safe abortion in cases of failed contraception. We conclude that reproductive health advocates must target legal professionals with a view to educating them on issues relating to sexual and reproductive health and rights. Lawyers in Nigeria should undergo capacity building in reproductive health laws and be encouraged to specialize in reproductive rights protection as obtainable in other developed countries.

Application of assisted reproduction for population management in felids: the potential and reality for conservation of small cats.

PubMed

Swanson, William F

2006-07-01

Assisted reproductive technology (ART), using the primary applied tools of AI, ET, and sperm and embryo cryopreservation, has been promoted over the past decades for its potential to conserve endangered wildlife, including felids. However, if the goal is efficient, consistent production of viable offspring for population management, then the 'potential' of ART has yet to become 'reality' for any non-domestic cat species. For the five small-sized felids (i.e., Brazilian ocelot, fishing cat, Pallas' cat, Arabian sand cat, black-footed cat) managed by Species Survival Plans (SSPs) in North American zoos, achieving this potential may be an absolute necessity if genetically viable captive populations are to be maintained into the next century. Modeling programs suggest that current SSP populations are not sustainable without periodic introduction of new founders and improved demographic parameters, including longer generation intervals and larger population sizes. ART provides the means to address each of these management challenges. In each small cat SSP species, fecal hormone metabolite assays and seminal analysis have proven useful for characterizing basal reproductive parameters, a necessary prerequisite to developing ART. Of the five SSP species, ART has been used to produce living offspring only in the ocelot, including after AI with frozen-thawed spermatozoa and following transfer of frozen-thawed IVF embryos. The true efficacy of these techniques, however, is still unknown. To improve the applicability of ART for population management, priorities for immediate research include further investigation of ovarian stimulation protocols, sperm and embryo cryopreservation methods, embryo culture systems, and fetal and neonatal viability following ART.

Ordinary kriging as a tool to estimate historical daily streamflow records

USGS Publications Warehouse

Farmer, William H.

2016-01-01

Efficient and responsible management of water resources relies on accurate streamflow records. However, many watersheds are ungaged, limiting the ability to assess and understand local hydrology. Several tools have been developed to alleviate this data scarcity, but few provide continuous daily streamflow records at individual streamgages within an entire region. Building on the history of hydrologic mapping, ordinary kriging was extended to predict daily streamflow time series on a regional basis. Pooling parameters to estimate a single, time-invariant characterization of spatial semivariance structure is shown to produce accurate reproduction of streamflow. This approach is contrasted with a time-varying series of variograms, representing the temporal evolution and behavior of the spatial semivariance structure. Furthermore, the ordinary kriging approach is shown to produce more accurate time series than more common, single-index hydrologic transfers. A comparison between topological kriging and ordinary kriging is less definitive, showing the ordinary kriging approach to be significantly inferior in terms of Nash–Sutcliffe model efficiencies while maintaining significantly superior performance measured by root mean squared errors. Given the similarity of performance and the computational efficiency of ordinary kriging, it is concluded that ordinary kriging is useful for first-order approximation of daily streamflow time series in ungaged watersheds.

Rapid and simple half-quantitative measurement alpha-fetoprotein by poly(dimethylsiloxane) microfluidic chip immunochromatographic assay

NASA Astrophysics Data System (ADS)

Tong, Chao; Jin, Qinghui; Zhao, Jianlong

2008-03-01

In this article, a kind of microfluidic method based on MEMS technology combined with gold immunochromatographic assay (GICA) is developed and discussed. Compared to the traditional GICA, this method supplies us convenient, multi-channel, in-parallel, low cost and similar efficiency approach in the fields of alpha-fetopro-tei (AFP)detection. Firstly, we improved the adhesion between the model material SU-8 and Silicon wafer, optimized approaches of the fabrication of the SU-8 model systematically, and fabricate the PDMS micro fluid chip with good reproduction successfully. Secondly, Surface modification and antibody immobilization methods with the GICA on the PDMS micro fluid analysis chip are studied, we choose the PDMS material and transfer GICA to the PDMS micro fluid chip successfully after researching the antibody immobilization efficiency of different materials utilized in fabrication of the micro fluid chip. In order to improve the reaction efficiency of the immobilized antibody, we studied the characteristics of micro fluid without the gas drive, and the fluid velocity control in our design; we also design structure of grove to strengthen the ability of immobilizing the antibody. The stimulation of the structure shows that it achieves great improvement and experiments prove the design is feasible.

Histological and morphological aspects of reproduction in the sandbar shark Carcharhinus plumbeus in the U.S. south-eastern Atlantic Ocean and Gulf of Mexico.

PubMed

Piercy, A N; Murie, D J; Gelsleichter, J J

2016-05-01

The reproduction of the sandbar shark Carcharhinus plumbeus in the U.S. south-eastern Atlantic Ocean including the Gulf of Mexico was examined using a combination of histological and morphological characteristics of C. plumbeus collected through fishery-dependent and -independent sampling programmes (n = 1,567). Indices of maturity were constructed using measurements of gonads, reproductive tracts and claspers, and sandbar sharks exhibited 50% maturity sizes of 140 and 148 cm fork length for males and females respectively. Gonado-somatic indices and variation in reproductive tract condition were used to determine seasonal trends in reproduction of mature C. plumbeus. Sandbar sharks have discrete seasonal reproductive cycles in which males produce sperm from January to May with a peak in May and females develop eggs from January to May with ovulation occurring in June. Females were shown to exhibit a >2 year reproductive cycle. Embryonic development was assessed through measurements of masses and lengths of uterine contents. Gestation was 12 months, from July to the following June, with parturition in late June. This research highlights a difference from previously reported data on the periodicity of female reproduction in C. plumbeus in the U.S. south-eastern Atlantic Ocean and Gulf of Mexico, which may have major effects on future C. plumbeus stock management. © 2016 The Fisheries Society of the British Isles.

Physiology of reproductive worker honey bees (Apis mellifera): insights for the development of the worker caste.

PubMed

Peso, Marianne; Even, Naïla; Søvik, Eirik; Naeger, Nicholas L; Robinson, Gene E; Barron, Andrew B

2016-02-01

Reproductive and behavioural specialisations characterise advanced social insect societies. Typically, the honey bee (Apis mellifera) shows a pronounced reproductive division of labour between worker and queen castes, and a clear division of colony roles among workers. In a queenless condition, however, both of these aspects of social organisation break down. Queenless workers reproduce, forage and maintain their colony operating in a manner similar to communal bees, rather than as an advanced eusocial group. This plasticity in social organisation provides a natural experiment for exploring physiological mechanisms of division of labour. We measured brain biogenic amine (BA) levels and abdominal fat body vitellogenin gene expression levels of workers in queenright and queenless colonies. Age, ovary activation and social environment influenced brain BA levels in honey bees. BA levels were most influenced by ovary activation state in queenless bees. Vitellogenin expression levels were higher in queenless workers than queenright workers, but in both colony environments vitellogenin expression was lower in foragers than non-foragers. We propose this plasticity in the interacting signalling systems that influence both reproductive and behavioural development allows queenless workers to deviate significantly from the typical worker bee reaction norm and develop as reproductively active behavioural generalists.

Ovarian function and reproductive senescence in the rat: role of ovarian sympathetic innervation.

PubMed

Cruz, Gonzalo; Fernandois, Daniela; Paredes, Alfonso H

2017-02-01

Successful reproduction is the result of a myriad interactions in which the ovary and the ovarian follicular reserve play a fundamental role. At present, women who delay maternity until after 30 years of age have a decreased fertility rate due to various causes, including damaged follicles and a reduction in the reserve pool of follicles. Therefore, the period just prior to menopause, also known as the subfertile period, is important. The possibility of modulating the follicular pool and the health of follicles during this period to improve fertility is worth exploring. We have developed an animal model to study the ovarian ageing process during this subfertile period to understand the mechanisms responsible for reproductive senescence. In the rat model, we have shown that the sympathetic nervous system participates in regulating the follicular development during ovarian ageing. This article reviews the existing evidence on the presence and functional role of sympathetic nerve activity in regulating the follicular development during ovarian ageing, with a focus on the subfertile period.Free Spanish abstract: A Spanish translation of this abstract is freely available at http://www.reproduction-online.org/content/153/2/R61/suppl/DC1. © 2017 Society for Reproduction and Fertility.

Experimental evaluation of reproductive response to climate warming in an oviparous skink.

PubMed

Lu, Hongliang; Wang, Yong; Tang, Wenqi; DU, Weiguo

2013-06-01

The impact of climate warming on organisms is increasingly being recognized. The experimental evaluation of phenotypically plastic responses to warming is a critical step in understanding the biological effects and adaptive capacity of organisms to future climate warming. Oviparous Scincella modesta live in deeply-shaded habitats and they require low optimal temperatures during embryonic development, which makes them suitable subjects for testing the effects of warming on reproduction. We raised adult females and incubated their eggs under different thermal conditions that mimicked potential climate warming. Female reproduction, embryonic development and hatchling traits were monitored to evaluate the reproductive response to warming. Experimental warming induced females to lay eggs earlier, but it did not affect the developmental stage of embryos at oviposition or the reproductive output. The high temperatures experienced by gravid females during warming treatments reduced the incubation period and increased embryonic mortality. The locomotor performance of hatchlings was not affected by the maternal thermal environment, but it was affected by the warming treatment during embryonic development. Our results suggest that climate warming might have a profound effect on fitness-relevant traits both at embryonic and post-embryonic stages in oviparous lizards. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

Evaluation of Follicular Synchronization Caused by Estrogen Administration and Its Reproductive Outcome

PubMed Central

Wu, Bi; Shi, Yan; Gong, Xia; Yu, Lin; Chen, Qiuju; Wang, Jian; Sun, Zhaogui

2015-01-01

To evaluate multiple follicular development synchronization after estrogen stimulation in prepubertal mice, follicular responsiveness to gonadotropin superovulation, the prospective reproductive potential and ovarian polycystic ovary syndrome (PCOS)-like symptoms at adulthood, prepubertal mice were intraperitoneally injected with estrogen to establish an animal model with solvent as control. When synchronized tertiary follicles in ovaries, in vitro oocyte maturation and fertilization rates, blastocyst formation rate, developmental potential into offspring by embryo transfer, adult fertility and PCOS-like symptoms, and involved molecular mechanisms were focused, it was found that estrogen stimulation (10μg/gBW) leads to follicular development synchronization at the early tertiary stage in prepubertal mice; reproduction from oocytes to offspring could be realized by means of the artificial reproductive technology though the model mice lost their natural fertility when they were reared to adulthood; and typical symptoms of PCOS, except changes in inflammatory pathways, were not remained up to adulthood. So in conclusion, estrogen can lead to synchronization in follicular development in prepubertal mice, but does not affect reproductive outcome of oocytes, and no typical symptoms of PCOS remained at adulthood despite changes related to inflammation. PMID:26010950

Reproductive Steroid Regulation of Mood and Behavior.

PubMed

Schiller, Crystal Edler; Johnson, Sarah L; Abate, Anna C; Schmidt, Peter J; Rubinow, David R

2016-06-13

In this article, we examine evidence supporting the role of reproductive steroids in the regulation of mood and behavior in women and the nature of that role. In the first half of the article, we review evidence for the following: (i) the reproductive system is designed to regulate behavior; (ii) from the subcellular to cellular to circuit to behavior, reproductive steroids are powerful neuroregulators; (iii) affective disorders are disorders of behavioral state; and (iv) reproductive steroids affect virtually every system implicated in the pathophysiology of depression. In the second half of the article, we discuss the diagnosis of the three reproductive endocrine-related mood disorders (premenstrual dysphoric disorder, postpartum depression, and perimenopausal depression) and present evidence supporting the relevance of reproductive steroids to these conditions. Existing evidence suggests that changes in reproductive steroid levels during specific reproductive states (i.e., the premenstrual phase of the menstrual cycle, pregnancy, parturition, and the menopause transition) trigger affective dysregulation in susceptible women, thus suggesting the etiopathogenic relevance of these hormonal changes in reproductive mood disorders. Understanding the source of individual susceptibility is critical to both preventing the onset of illness and developing novel, individualized treatments for reproductive-related affective dysregulation. © 2016 American Physiological Society. Compr Physiol 6:1135-1160, 2016e. Copyright © 2016 John Wiley & Sons, Inc.

Interannual variability of growth and reproduction in Bursera simaruba: the role of allometry and resource variability.

PubMed

Hulshof, Catherine M; Stegen, James C; Swenson, Nathan G; Enquist, Carolyn A F; Enquist, Brian J

2012-01-01

Plants are expected to differentially allocate resources to reproduction, growth, and survival in order to maximize overall fitness. Life history theory predicts that the allocation of resources to reproduction should occur at the expense of vegetative growth. Although it is known that both organism size and resource availability can influence life history traits, few studies have addressed how size dependencies of growth and reproduction and variation in resource supply jointly affect the coupling between growth and reproduction. In order to understand the relationship between growth and reproduction in the context of resource variability, we utilize a long-term observational data set consisting of 670 individual trees over a 10-year period within a local population of Bursera simaruba (L.) Sarg. We (1) quantify the functional form and variability in the growth-reproduction relationship at the population and individual-tree level and (2) develop a theoretical framework to understand the allometric dependence of growth and reproduction. Our findings suggest that the differential responses of allometric growth and reproduction to resource availability, both between years and between microsites, underlie the apparent relationship between growth and reproduction. Finally, we offer an alternative approach for quantifying the relationship between growth and reproduction that accounts for variation in allometries.

Reproduction, genetics and the law.

PubMed

Crockin, Susan L

2005-06-01

Both reproductive medicine and genetics are seeing rapid, and in some instances revolutionary, medical and scientific advances. Courts have been called upon to resolve a variety of novel disputes arising from these areas, and more can be anticipated as these technologies continue to develop and their use becomes more widespread. This article discusses some of the most relevant areas of the law and litigation that currently bear on reproduction and genetics or that may be anticipated to do so in the future. Specific developments and judicial decisions addressing them include: legal theories of wrongful birth and wrongful life and their application to children born with genetic impairments; a physician's duty to warn family members about a relative's genetic disease; disputes over reproductive materials and non-reproductive cells and tissues; unauthorized genetic testing in the workplace; and genetic discrimination. It is hoped that this discussion will be of value to medical and legal professionals and policy makers who work with these concepts in the increasingly inter-related fields of law and medicine.

Mutation independently affects reproductive traits and dauer larvae development in mutation accumulation lines of Caenorhabditis elegans.

PubMed

Hills, Arthur J; Green, James W M; Harvey, Simon C

2017-11-01

Developmental decisions are important in organismal fitness. For the nematode Caenorhabditis elegans, which is naturally found in the ephemeral food patches formed by rotting plant material, correctly committing to dauer or non-dauer larval development is key to genotype survival. To investigate the link between reproductive traits, which will determine how populations grow, and dauer larvae formation, we have analysed these traits in mutation accumulation lines of C. elegans. We find that reproductive traits of individual worms-the total number of progeny and the timing of progeny production-are highly correlated with the population size observed in growing populations. In contrast, we find no relationship between reproduction traits and the number of dauer larvae observed in growing populations. We also do not observe a mutational bias in dauer larvae formation. These results indicate that the control of dauer larvae formation is distinct from the control of reproduction and that differences in dauer larvae formation can evolve rapidly.

Cyclic variations in nitrogen uptake rate in soybean plants: uptake during reproductive growth

NASA Technical Reports Server (NTRS)

Vessey, J. K.; Raper, C. D. Jr; Henry, L. T.; Raper CD, J. r. (Principal Investigator)

1990-01-01

Net uptake of NO3- by non-nodulated soybean plants [Glycine max (L.) Merr. cv. Ransom] growing in flowing hydroponic culture was measured daily during a 63 d period of reproductive development between the first florally inductive photoperiod and [unknown word] seed growth. Removal of NO3- from a replenished solution containing 1.0 mol m-3 NO3- was determined by ion chromatography. Uptake of NO3- continued throughout reproductive development. The net uptake rate of NO3- cycled between maxima and minima with a periodicity of oscillation of 3 to 7 d during the floral stage and about 6 d during the fruiting stage. Coupled with increasing concentrations of carbon and C : N ratios in tissues, the oscillations in net uptake rates of NO3- are evidence that the demand for carbohydrate by reproductive organs is contingent on the availability of nitrogen in the shoot pool rather than that the demand for nitrogen follows the flux of carbohydrate into reproductive tissues.

Reproductive and Endocrine Biomarkers in Largemouth Bass (Micropterus salmoides) and Common Carp (Cyprinus carpio) from United States Waters

USGS Publications Warehouse

Goodbred, Steven L.; Smith, Stephen B.; Greene, Patricia S.; Rauschenberger, Richard H.; Bartish, Timothy M.

2007-01-01

A nationwide reconnaissance investigation was initiated in 1994 to develop and evaluate a suite of reproductive and endocrine biomarkers for their potential to assess reproductive health and status in teleost (bony) fish. Fish collections were made at 119 sites, representing many regions of the country and land- and water-use settings. Collectively, this report will provide a national and regional benchmark and a basis for evaluating biomarkers of endocrine and reproductive function. Approximately 2,200 common carp (Cyprinus carpio) and 650 largemouth bass (Micropterus salmoides) were collected from 1994 through 1997. The suite of biomarkers used for these studies included: the plasma sex-steroid hormones, 17?-estradiol (E2) and 11 ketotestosterone (11KT); the ratio of E2 to 11KT (E2:11KT); plasma vitellogenin (VTG); and stage of gonadal development. This data report provides fish size, stage and reproductive biomarker data for individual fish and for site and regional summaries of these variables.

'Man Up': the importance and strategy for placing male reproductive health centre stage in the political and research agenda.

PubMed

Barratt, Christopher L R; De Jonge, Christopher J; Sharpe, Richard M

2018-04-01

Approximately 1 in 20 young men today have sperm counts low enough to impair fertility, whereas this may not have been the case historically. The cause(s) of such a decline in male reproductive health is unknown, despite it being a global health issue. Concomitantly, little progress has been made in answering fundamental questions in andrology or in developing new diagnostic tools or alternative management strategies to ICSI in infertile men. We advocate formulation of a detailed roadmap for male reproductive health to facilitate development of a research agenda that highlights the present unmet needs and key unanswered questions, and seeks to deliver effective funding and investment to address them. This vision we term 'a Male Reproductive Health Ecosystem'.

Lysophosphatidic Acid (LPA) Signaling in Human and Ruminant Reproductive Tract

PubMed Central

Wocławek-Potocka, Izabela; Rawińska, Paulina; Kowalczyk-Zieba, Ilona; Boruszewska, Dorota; Sinderewicz, Emilia; Waśniewski, Tomasz; Skarzynski, Dariusz Jan

2014-01-01

Lysophosphatidic acid (LPA) through activating its G protein-coupled receptors (LPAR 1–6) exerts diverse cellular effects that in turn influence several physiological processes including reproductive function of the female. Studies in various species of animals and also in humans have identified important roles for the receptor-mediated LPA signaling in multiple aspects of human and animal reproductive tract function. These aspects range from ovarian and uterine function, estrous cycle regulation, early embryo development, embryo implantation, decidualization to pregnancy maintenance and parturition. LPA signaling can also have pathological consequences, influencing aspects of endometriosis and reproductive tissue associated tumors. The review describes recent progress in LPA signaling research relevant to human and ruminant reproduction, pointing at the cow as a relevant model to study LPA influence on the human reproductive performance. PMID:24744506

Reproductive Ontogeny of Wheat Grown on the MIR Space Station

NASA Technical Reports Server (NTRS)

Bubenheim, David L.; Stieber, Joseph

1997-01-01

The reproductive ontogeny of 'Super-Dwarf' wheat grown on the space station Mir is chronicled from the vegetative phase through flower development. Changes in the apical meristem associated with transition From the vegetative phase to floral initiation and development of the reproductive spike were all typical of 'Super Dwarf' wheat up to the point of anthesis. Filament elongation, which characteristically occurs just prior to anthesis and moves the anthers through the stigmatic branches thus facilitating pollination, did no1 xcur in the flowers of spikes grown on Mir. While development of spikes on tillers typically occurs later :han that of spikes on the main stem, all flowers appear to be arrested at the same developmental point.

DEVELOPMENT OF FILMSTRIP SEQUENCE PHOTOGRAPHS AND SOUND REPRODUCTION OF EDUCATIONAL TELEVISION PRESENTATIONS.

ERIC Educational Resources Information Center

MARTINI, HARRY R.

BLACK AND WHITE FILMSTRIPS THAT REPRODUCED STILL PICTURES AND SOUND TRACK FROM EDUCATIONAL TELEVISION BROADCASTS WERE USED TO STUDY THE EFFECTIVENESS OF ETV REPRODUCTIONS IN AIDING POOR ACHIEVERS. THE SPECIFIC ADVANTAGE OF SUCH A REPRODUCTION WAS THAT IT COULD BE PACED TO THE LEARNING TEMPO OF THE STUDENTS RATHER THAN USING THE TOO-FAST PACE OF A…

Regeneration Development Across a Range of Reproduction Cutting Methods in Shortleaf Pine and Pine-Hardwood Stands in the Interior Highlands

Treesearch

James M. Guldin; James B. Baker; Michael G. Shelton

2004-01-01

Abstract - Density, milacre stocking, and height of shortleaf pine ( Pinus echinata Mill.) regeneration under 13 reproduction cutting methods were measured after 5 growing seasons across a range of reproduction cutting treatments in shortleaf pine and pine-hardwood stands in the Interior Highlands of Arkansas and Oklahoma. A subset...

Religious aspects of assisted reproduction

PubMed Central

Sallam, HN; Sallam, NH

2016-01-01

Abstract Human response to new developments regarding birth, death, marriage and divorce is largely shaped by religious beliefs. When assisted reproduction was introduced into medical practice in the last quarter of the twentieth century, it was fiercely attacked by some religious groups and highly welcomed by others. Today, assisted reproduction is accepted in nearly all its forms by Judaism, Hinduism and Buddhism, although most Orthodox Jews refuse third party involvement. On the contrary assisted reproduction is totally unacceptable to Roman Catholicism, while Protestants, Anglicans, Coptic Christians and Sunni Muslims accept most of its forms, which do not involve gamete or embryo donation. Orthodox Christians are less strict than Catholic Christians but still refuse third party involvement. Interestingly, in contrast to Sunni Islam, Shi’a Islam accepts gamete donation and has made provisions to institutionalize it. Chinese culture is strongly influenced by Confucianism, which accepts all forms of assisted reproduction that do not involve third parties. Other communities follow the law of the land, which is usually dictated by the religious group(s) that make(s) the majority of that specific community. The debate will certainly continue as long as new developments arise in the ever-evolving field of assisted reproduction. PMID:27822349

Reproductive competence: a recurrent logic module in eukaryotic development

PubMed Central

Noble, Luke M.; Andrianopoulos, Alex

2013-01-01

Developmental competence is the ability to differentiate in response to an appropriate stimulus, as first elaborated by Waddington in relation to organs and tissues. Competence thresholds operate at all levels of biological systems from the molecular (e.g. the cell cycle) to the ontological (e.g. metamorphosis and reproduction). Reproductive competence, an organismal process, is well studied in mammals (sexual maturity) and plants (vegetative phase change), though far less than later stages of terminal differentiation. The phenomenon has also been documented in multiple species of multicellular fungi, mostly in early, disparate literature, providing a clear example of physiological differentiation in the absence of morphological change. This review brings together data on reproductive competence in Ascomycete fungi, particularly the model filamentous fungus Aspergillus nidulans, contrasting mechanisms within Unikonts and plants. We posit reproductive competence is an elementary logic module necessary for coordinated development of multicellular organisms or functional units. This includes unitary multicellular life as well as colonial species both unicellular and multicellular (e.g. social insects such as ants). We discuss adaptive hypotheses for developmental and reproductive competence systems and suggest experimental work to address the evolutionary origins, generality and genetic basis of competence in the fungal kingdom. PMID:23864594

From fresh heterologous oocyte donation to autologous oocyte banking

PubMed Central

Stoop, D.

2012-01-01

Introduction: Today, oocyte donation has become well established, giving rise to thousands of children born worldwide annually. The introduction of oocyte cryopreservation through vitrification allows the introduction of egg banking, improving the efficiency and comfort of oocyte donation. Moreover, the vitrification technique can now enable autologous donation of oocytes to prevent future infertility. Methods: We evaluated fresh heterologous oocyte donation in terms of obstetrical and perinatal outcome as well as of the reproductive outcome of past donors. We then evaluated the efficiency of a closed vitrification device and its clinical applications within ART. Thirdly, we evaluated the opinion of women with regard to preventive egg freezing and the efficiency of a human oocyte in relation to age. Results: Oocyte donation is associated with an increased risk of first trimester bleeding and pregnancy induced hypertension. Donating oocytes does not seem to increase the likelihood for a later need of fertility treatment. The chance of an oocyte to result in live birth (utilization rate) in women <37 years old remains constant with a mean of 4.47%. A significant proportion of young women would consider safeguarding their reproductive potential through egg freezing or are at least open to the idea. Discussion and Conclusion: The introduction of efficient oocyte cryopreservation has revolutionized oocyte donation through the establishment of eggbank donation. The technique also enables women to perform autologous donation after preventive oocyte storage in order to circumvent their biological clock. PMID:24753920

NTP-CERHR monograph on the potential human reproductive and developmental effects of di (2-ethylhexyl) phthalate (DEHP).

PubMed

Shelby, Michael D

2006-11-01

The National Toxicology Program (NTP) Center for the Evaluation of Risks to Human Reproduction (CERHR) conducted an updated evaluation of the potential for DEHP to cause adverse effects on reproduction and development in humans. The first CERHR expert panel evaluation of DEHP was completed in 2000 by the Phthalates Expert Panel. CERHR selected DEHP for an updated evaluation because of: (1) widespread human exposure, (2) public and government interest in adverse health effects, (3) recently available human exposure studies, and (4) the large number of relevant toxicity papers published since the earlier evaluation. DEHP (CAS RN: 117-81-7) is a high production volume chemical used as a plasticizer of polyvinyl chloride in the manufacture of a wide variety of consumer goods, such as building products, car products, clothing, food packaging, children's products (but not in toys intended for mouthing), and in medical devices made of polyvinyl chloride. The public can be exposed to DEHP by ingesting food, drink or dust that has been in contact with DEHP-containing materials, by inhaling contaminated air or dust, or by undergoing a medical procedure that uses polyvinyl chloride medical tubing or storage bags. It is estimated that the general population of the United States is exposed to DEHP levels ranging from 1 to 30 microg/kg bw/day (micrograms per kilogram body weight per day). The results of this DEHP update evaluation are published in an NTP-CERHR monograph that includes: (1) the NTP Brief, (2) the Expert Panel Update on the Reproductive and Developmental Toxicity of DEHP, and (3) public comments on the expert panel report. The NTP reached the following conclusions on the possible effects of exposure to DEHP on human development and reproduction. Note that the possible levels of concern, from lowest to highest, are negligible concern, minimal concern, some concern, concern, and serious concern. There is serious concern that certain intensive medical treatments of male infants may result in DEHP exposure levels that adversely affect development of the male reproductive tract. DEHP exposure from medical procedures in infants was estimated to be as high as 6000 microg/kg bw/day. There is concern for adverse effects on development of the reproductive tract in male offspring of pregnant and breast feeding women undergoing certain medical procedures that may result in exposure to high levels of DEHP. There is concern for effects of DEHP exposure on development of the male reproductive tract for infants less than one year old. Diet, mouthing of DEHP-containing objects, and certain medical treatments may lead to DEHP exposures that are higher than those experienced by the general population. There is some concern for effects of DEHP exposure on development of the reproductive tract of male children older than one year. As in infants, exposures of children to DEHP may be higher than in the general population. There is some concern for adverse effects of DEHP exposure on development of the male reproductive tract in male offspring of pregnant women not medically exposed to DEHP. Although DEHP exposures are assumed to be the same as for the general population, the developing male reproductive tract is sensitive to the adverse effects of DEHP. There is minimal concern for reproductive toxicity in adults exposed to DEHP at 1 - 30 microg/kg bw/day. This level of concern is not altered for adults medically exposed to DEHP. NTP will transmit the NTP-CERHR Monograph on DEHP to federal and state agencies, interested parties, and the public and it will be available in electronic PDF format on the CERHR web site http://cerhr.niehs.nih.gov and in printed text or CD-ROM from the CERHR.

The reproductive morphology and physiological age grading of the female Salvinia Weevil, Cyrtobagous salviniae Calder and Sands

USDA-ARS?s Scientific Manuscript database

The morphology of female Cyrtobagous salviniae Calder and Sands reproductive system is similar to other weevil species being meroistic and telotrophic and composed of two ovaries each with two tube-like ovarioles where the follicles develop and mature. A physiological age-grading system was develop...

Threat to food security under current levels of ground level ozone: A case study for Indian cultivars of rice

NASA Astrophysics Data System (ADS)

Rai, Richa; Agrawal, Madhoolika; Agrawal, S. B.

2010-11-01

A higher ozone concentration in rural agricultural region poses threat to food production in developing countries. The present study was conducted to evaluate the growth, biomass accumulation and allocation pattern, quantitative and qualitative characteristics of grains for two tropical rice cultivars ( Oryza sativa L. cv NDR 97 and Saurabh 950) at ambient O 3 concentrations at a rural site in the Indo Gangetic plains of India. Percent inhibition in number of leaves was higher for NDR 97, but in leaf area for Saurabh 950 grown in non filtered chambers (NFCs) compared to filtered chambers (FCs). Higher inhibition in root biomass was recorded in Saurabh 950 and in leaf and standing dead biomass for NDR 97. During vegetative phase, relative growth rate showed more percent inhibition in Saurabh 950, but at reproductive phase in NDR 97. Net assimilation rate showed higher values for Saurabh 950 than NDR 97 in NFCs but percent inhibition in leaf area ratio was higher for former than latter cultivar in NFCs. The ozone resistance was higher in NDR 97 during vegetative phase, but in Saurabh 950 at reproductive phase. Number of grains was higher in NDR 97 than Saurabh 950, but test weight and weight of grains m -2 showed reverse trends. Concentrations of starch, protein, P, N, Ca, Mg and K decreased, while reducing and total soluble sugar increased in grains of both the cultivars in NFCs compared to FCs. The study concluded that under ambient condition of O 3 exposure, the two cultivars responded differently. Saurabh 950 favoured biomass translocation priority towards ear in reproductive phase and hence showed higher resistivity due to maintenance of higher test weight. NDR 97, however, showed better growth during vegetative period, but could not allocate efficiently to developing ears, hence higher number of unfilled grains in NFCs led lower test weight.

Progress with oocyte cryopreservation.

PubMed

Porcu, Eleonora; Venturoli, Stefano

2006-06-01

This article reviews human oocyte cryopreservation, one of the most stimulating challenges of assisted reproduction technology. Since the first steps in assisted reproduction technology, researchers have pursued this goal, to greatly improve the management of infertility treatments. This present review depicts the present state of research and clinical applications of this methodology. Recent literature focuses on the possible mechanisms of oocyte damage caused by temperature and cryoprotectant injury and forecasts possible technological solutions. Several papers illustrate encouraging results in the increasing clinical application of this procedure. Findings give support to several indications of human female gamete cryostorage. Oocyte cryopreservation might replace embryo freezing. Egg freezing offers an alternative to women at risk of losing their reproductive function, caused by antineoplastic treatments, endometriosis, ovarian surgery or genetic premature ovarian failure. In addition, oocyte storage may contribute to an increase in in-vitro fertilization flexibility. Despite the early disappointing results, recent technical modifications have improved the clinical efficiency greatly, with the birth of several healthy children.

Characterization of the gut bacterial community in Manduca sexta and effect of antibiotics on bacterial diversity and nematode reproduction.

PubMed

van der Hoeven, Ransome; Betrabet, Geeta; Forst, Steven

2008-09-01

The tobacco hornworm, Manduca sexta, is a model lepidopteran insect used to study the pathogenic and mutualistic phases of entomopathogenic nematodes (EPNs) and their bacterial symbionts. While intestinal microbial communities could potentially compete with the EPN and its bacterial partner for nutrient resources of the insect, the microbial gut community had not been characterized previously. Here, we show that the midgut of M. sexta raised on an artificial diet contained mostly Gram-positive cocci and coryneforms including Staphylococcus, Pediococcus, Micrococcus and Corynebacterium. Major perturbation in the gut community was observed on addition of antibiotics to the diet. Paenibacillus and several Proteobacteria such as Methylobacterium, Sphingomonas and Acinetobacter were primary genera identified under these conditions. Furthermore, the reproduction of the nematode Steinernema carpocapsae was less efficient, and the level of nematode colonization by its symbiont Xenorhabdus nematophila reduced, in insects reared on a diet containing antibiotics. The effect of antibiotics and perturbation of gut microbiota on nematode reproduction is discussed.

A combinational theory for maintenance of sex

PubMed Central

Hörandl, E

2010-01-01

Sexual reproduction implies high costs, but it is difficult to give evidence for evolutionary advantages that would explain the predominance of meiotic sex in eukaryotes. A combinational theory discussing evolution, maintenance and loss of sex may resolve the problem. The main function of sex is the restoration of DNA and consequently a higher quality of offspring. Recombination at meiosis evolved, perhaps, as a repair mechanism of DNA strand damages. This mechanism is most efficient for DNA restoration in multicellular eukaryotes, because the initial cell starts with a re-optimized genome, which is passed to all the daughter cells. Meiosis acts also as creator of variation in haploid stages, in which selection can purge most efficiently deleterious mutations. A prolonged diploid phase buffers the effects of deleterious recessive alleles as well as epigenetic defects and is thus optimal for prolonged growth periods. For complex multicellular organisms, the main advantage of sexuality is thus the alternation of diploid and haploid stages, combining advantages of both. A loss of sex is constrained by several, partly group-specific, developmental features. Hybridization may trigger shifts from sexual to asexual reproduction, but crossing barriers of the parental sexual species limit this process. For the concerted break-up of meiosis-outcrossing cycles plus silencing of secondary features, various group-specific changes in the regulatory system may be required. An establishment of asexuals requires special functional modifications and environmental opportunities. Costs for maintenance of meiotic sex are consequently lower than a shift to asexual reproduction. PMID:19623209

Seasonal patterns of winter flounder Pseudopleuronectes americanus abundance and reproductive condition on the New York Bight continental shelf.

PubMed

Wuenschel, M J; Able, K W; Byrne, D

2009-05-01

To resolve varied and sometimes conflicting accounts of spawning and habitat characteristics for winter flounder Pseudopleuronectes americanus, seasonal patterns in abundance and reproductive condition were investigated in the New York Bight, near the southern edge of their current reproductive range. Fish were collected from trawl surveys on the inner continental shelf from October 2006 to October 2007. Pseudopleuronectes americanus were most abundant during January and April surveys, were rarely collected in August, with intermediate abundances in June and October. Measurements of fish condition [hepato-somatic index (I(H)), condition factor (K) and the per cent dry mass of muscle tissue (%M(D))] and reproductive condition [gonado-somatic index (I(G))] were determined to evaluate seasonal changes in energy accumulation and depletion and reproduction. Males and females had similar patterns in body and reproductive condition, although the magnitude of change was greater for females. I(H) values were highest during spring and early summer, suggesting increased feeding following spawning. K and %M(D) increased through spring and summer then declined in the autumn and winter concurrent with gonadal development. Gonads began developing in the autumn, and in January, I(G) values approached spawning levels, with many spent individuals collected in spring. Within these general patterns, however, there was a large degree of variability among individuals, and a few mature non-reproductive ('skipped spawning') females were observed. In the period after spawning, increased energy intake, indicated by increased I(H), may influence reproductive output since this energy is gradually transferred to the muscle and used for gonadal development in the forthcoming year. The occurrence of ripening individuals on the inner continental shelf in January suggests that these fish either rapidly move into estuaries to spawn by February-March or they remain on the inner shelf to spawn, or some combination of these. Future studies should evaluate these possibilities, as both estuarine and inner shelf habitats are potentially affected by activities such as dredging, sand dredging and wind energy development.

Polarity establishment, morphogenesis, and cultured plant cells in space

NASA Technical Reports Server (NTRS)

Krikorian, Abraham D.

1989-01-01

Plant development entails an orderly progression of cellular events both in terms of time and geometry. There is only circumstantial evidence that, in the controlled environment of the higher plant embryo sac, gravity may play a role in embryo development. It is still not known whether or not normal embryo development and differentiation in higher plants can be expected to take place reliably and efficiently in the micro g space environment. It seems essential that more attention be given to studying aspects of reproductive biology in order to be confident that plants will survive seed to seed to seed in a space environment. Until the time arrives when successive generations of plants can be grown, the best that can be done is utilize the most appropriate systems and begin, piece meal, to accumulate information on important aspects of plant reproduction. Cultured plant cells can play an important role in these activities since they can be grown so as to be morphogenetically competent, and thus can simulate those embryogenic events more usually identified with fertilized eggs in the embryo sac of the ovule in the ovary. Also, they can be manipulated with relative ease. The extreme plasticity of such demonstrably totipotent cell systems provides a means to test environmental effects such as micro g on a potentially free-running entity. The successful manipulation and management of plant cells and propagules in space also has significance for exploitation of biotechnologies in space since such systems, perforce, are an important vehicle whereby many genetic engineering manipulations are achieved.

Live Births from Domestic Dog (Canis familiaris) Embryos Produced by In Vitro Fertilization

PubMed Central

Nagashima, Jennifer B.; Sylvester, Skylar R.; Nelson, Jacquelyn L.; Cheong, Soon Hon; Mukai, Chinatsu; Lambo, Colleen; Flanders, James A.; Meyers-Wallen, Vicki N.; Songsasen, Nucharin; Travis, Alexander J.

2015-01-01

Development of assisted reproductive technologies (ART) in the dog has resisted progress for decades, due to their unique reproductive physiology. This lack of progress is remarkable given the critical role ART could play in conserving endangered canid species or eradicating heritable disease through gene-editing technologies—an approach that would also advance the dog as a biomedical model. Over 350 heritable disorders/traits in dogs are homologous with human conditions, almost twice the number of any other species. Here we report the first live births from in vitro fertilized embryos in the dog. Adding to the practical significance, these embryos had also been cryopreserved. Changes in handling of both gametes enabled this progress. The medium previously used to capacitate sperm excluded magnesium because it delayed spontaneous acrosome exocytosis. We found that magnesium significantly enhanced sperm hyperactivation and ability to undergo physiologically-induced acrosome exocytosis, two functions essential to fertilize an egg. Unlike other mammals, dogs ovulate a primary oocyte, which reaches metaphase II on Days 4–5 after the luteinizing hormone (LH) surge. We found that only on Day 6 are oocytes consistently able to be fertilized. In vitro fertilization of Day 6 oocytes with sperm capacitated in medium supplemented with magnesium resulted in high rates of embryo development (78.8%, n = 146). Intra-oviductal transfer of nineteen cryopreserved, in vitro fertilization (IVF)-derived embryos resulted in seven live, healthy puppies. Development of IVF enables modern genetic approaches to be applied more efficiently in dogs, and for gamete rescue to conserve endangered canid species. PMID:26650234

[The impact of the social economic conditions on the reproduction processes].

PubMed

Leonova, N G

2007-01-01

The social economic conditions of population reproduction in the Trans-Dniester Region with the emphasis on its specifics are analyzed. The natural dynamics of population is estimated including gender and age peculiarities, marriage and divorces statistics, migration processes and population health in the region. It is shown that the population reproduction dynamics follows the natural laws and processes. The role of the post-Soviet period social economic conditions harmful to health are considered. The interdependencies between the social economic development and population reproduction are revealed. The recommendations related to the means of the further enhancement of social economic conditions as related to population reproduction in the Trans-Dniester Region are proposed.

Life cycle biological efficiency of mice divergently selected for heat loss.

PubMed

Bhatnagar, A S; Nielsen, M K

2014-08-01

Divergent selection in mice for heat loss was conducted in 3 independent replicates creating a high maintenance, high heat loss (MH) and low maintenance, low heat loss (ML) line and unselected control (MC). Improvement in feed efficiency was observed in ML mice due to a reduced maintenance energy requirement but there was also a slight decline in reproductive performance, survivability, and lean content, particularly when compared to MC animals. The objective of this study was to model a life cycle scenario similar to a livestock production system and calculate total inputs and outputs to estimate overall biological efficiency of these lines and determine if reduced feed intake resulted in improved life cycle efficiency. Feed intake, reproductive performance, growth, and body composition were recorded on 21 mating pairs from each line × replicate combination, cohabitated at 7 wk of age and maintained for up to 1 yr unless culled. Proportion of animals at each parity was calculated from survival rates estimated from previous research when enforcing a maximum of 4, 8, or 12 allowed parities. This parity distribution was then combined with values from previous studies to calculate inputs and outputs of mating pairs and offspring produced in a single cycle at equilibrium. Offspring output was defined as kilograms of lean output of offspring at 49 d. Offspring input was defined as megacalories of energy intake for growing offspring from 21 to 49 d. Parent output was defined as kilograms of lean output of culled parents. Parent input was defined as megacalories of energy intake for mating pairs from weaning of one parity to weaning of the next. Offspring output was greatest in MC mice due to superior BW and numbers weaned, while output was lowest in ML mice due to smaller litter sizes and lean content. Parent output did not differ substantially between lines but was greatest in MH mice due to poorer survival rates resulting in more culled animals. Input was greatest in MH and lowest for ML mice for both offspring and parent pairs, consistent with previous results in these lines. Life cycle efficiency was similar in MC and ML mice, while MH mice were least efficient. Ultimately, superior output in MC mice slightly outweighed the lower inputs in ML animals resulting from decreased maintenance energy requirements. Therefore, selection to reduce maintenance energy requirements may be more useful in terminal crosses or in a selection index to reduce possible negative effects on output, especially reproductive performance.

Reproduction and Breast Cancer Risk

PubMed Central

Hanf, Volker; Hanf, Dorothea

2014-01-01

Summary Reproduction is doubtlessly one of the main biological meanings of life. It is therefore not surprising that various aspects of reproduction impact on breast cancer risk. Various developmental levels may become targets of breast tumorigenesis. This review follows the chronologic sequence of events in the life of a female at risk, starting with the intrauterine development. Furthermore, the influence of both contraceptive measures and fertility treatment on breast cancer development is dealt with, as well as various pregnancy-associated factors, events, and perinatal outcomes. Finally, the contribution of breast feeding to a reduced breast cancer risk is discussed. PMID:25759622

Effectiveness of a reproductive sexual health education package among school going adolescents.

PubMed

Nair, M K C; Paul, Mini K; Leena, M L; Thankachi, Yamini; George, Babu; Russell, P S; Pillai, H Vijayan

2012-01-01

To assess the effectiveness of a school based "Adolescent Reproductive Sexual Health Education (ARSHE) Package" in improving students' knowledge on reproductive sexual health matters. An ARSHE package originally developed at Child Development Centre, Kerala, modified and approved by ICMR taskforce group was administered in three urban schools (One boys only, one girls only and one co-education) and one co-education rural school at Thiruvananthapuram district, Kerala. The study sample consisted of 1,586 adolescents including 996 boys and 560 girls of class IX and XI. Pre and post intervention knowledge regarding reproductive sexual health matters was assessed using a self-administered questionnaire. In the pre-intervention period, it was observed that majority of adolescents were poorly informed about reproductive sexual health matters, particularly about contraceptives. As compared to boys, girls had much poorer knowledge about prevention of pregnancy and after intervention; there was a statistically significant increase in the knowledge in both boys and girls. Among girls percentage of poor knowledge had reduced significantly from 64.1% to 8.3% and among boys from 37.7% to 3.5%. Similarly, increase in knowledge level was also observed in various other aspects of reproductive and sexual health including, STI, HIV/AIDS and perceptions about premarital sex. The study results revealed the feasibility and effectiveness of school based reproductive and sexual health education intervention programs for adolescents.

Environmental endocrine disruptors: Effects on the human male reproductive system.

PubMed

Sweeney, M F; Hasan, N; Soto, A M; Sonnenschein, C

2015-12-01

Incidences of altered development and neoplasia of male reproductive organs have increased during the last 50 years, as shown by epidemiological data. These data are associated with the increased presence of environmental chemicals, specifically "endocrine disruptors," that interfere with normal hormonal action. Much research has gone into testing the effects of specific endocrine disrupting chemicals (EDCs) on the development of male reproductive organs and endocrine-related cancers in both in vitro and in vivo models. Efforts have been made to bridge the accruing laboratory findings with the epidemiological data to draw conclusions regarding the relationship between EDCs, altered development and carcinogenesis. The ability of EDCs to predispose target fetal and adult tissues to neoplastic transformation is best explained under the framework of the tissue organization field theory of carcinogenesis (TOFT), which posits that carcinogenesis is development gone awry. Here, we focus on the available evidence, from both empirical and epidemiological studies, regarding the effects of EDCs on male reproductive development and carcinogenesis of endocrine target tissues. We also critique current research methodology utilized in the investigation of EDCs effects and outline what could possibly be done to address these obstacles moving forward.

Male pregnancy in seahorses and pipefish: beyond the mammalian model.

PubMed

Stölting, Kai N; Wilson, Anthony B

2007-09-01

Pregnancy has been traditionally defined as the period during which developing embryos are incubated in the body after egg-sperm union. Despite strong similarities between viviparity in mammals and other vertebrate groups, researchers have historically been reluctant to use the term pregnancy for non-mammals in recognition of the highly developed form of viviparity in eutherians. Syngnathid fishes (seahorses and pipefishes) have a unique reproductive system, where the male incubates developing embryos in a specialized brooding structure in which they are aerated, osmoregulated, protected and likely provisioned during their development. Recent insights into physiological, morphological and genetic changes associated with syngnathid reproduction provide compelling evidence that male incubation in these species is a highly specialized form of reproduction akin to other forms of viviparity. Here, we review these recent advances, highlighting similarities and differences between seahorse and mammalian pregnancy. Understanding the changes associated with the parallel evolution of male pregnancy in the two major syngnathid lineages will help to identify key innovations that facilitated the development of this unique form of reproduction and, through comparison with other forms of live bearing, may allow the identification of a common set of characteristics shared by all viviparous organisms.

A transcriptomics investigation into pine reproductive organ development.

PubMed

Niu, Shihui; Yuan, Huwei; Sun, Xinrui; Porth, Ilga; Li, Yue; El-Kassaby, Yousry A; Li, Wei

2016-02-01

The development of reproductive structures in gymnosperms is still poorly studied because of a lack of genomic information and useful genetic tools. The hermaphroditic reproductive structure derived from unisexual gymnosperms is an even less studied aspect of seed plant evolution. To extend our understanding of the molecular mechanism of hermaphroditism and the determination of sexual identity of conifer reproductive structures in general, unisexual and bisexual cones from Pinus tabuliformis were profiled for gene expression using 60K microarrays. Expression patterns of genes during progression of sexual cone development were analysed using RNA-seq. The results showed that, overall, the transcriptomes of male structures in bisexual cones were more similar to those of female cones. However, the expression of several MADS-box genes in the bisexual cones was similar to that of male cones at the more juvenile developmental stage, while despite these expression shifts, male structures of bisexual cones and normal male cones were histologically indistinguishable and cone development was continuous. This study represents a starting point for in-depth analysis of the molecular regulation of cone development and also the origin of hermaphroditism in pine. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Reproductive strategy of the Patagonian catfish Hatcheria macraei.

PubMed

Chiarello-Sosa, J M; Battini, M A; Barriga, J P

2016-09-01

This study describes the reproductive strategy of the stream-dwelling catfish Hatcheria macraei in the Pichileufu River, Argentina. Gonad maturity phases, classified on the basis of histological analysis, stages of gamete development and the frequency distribution of oocyte size, were correlated with macroscopic features of the gonads. Hatcheria macraei has a cystovarian ovary, asynchronous oocyte development and lobular testes. Five oocyte and four spermatogenic stages were identified and related to macroscopic gonad characteristics, making it possible to divide gonad development into five phases for females and males. Mature oocyte diameter ranged from 922 to 1935 µm. Absolute fecundity in mature females varied from 115 to 480 oocytes. Hatcheria macraei has multiple spawning during a protracted reproductive season that extends from December to April. This, together with its small size, is characteristic of an opportunistic reproductive strategy, commonly found in species that inhabit adverse and unpredictable environments, such as the low-order rivers of Patagonia. © 2016 The Fisheries Society of the British Isles.

Autophagy, programmed cell death and reactive oxygen species in sexual reproduction in plants.

PubMed

Kurusu, Takamitsu; Kuchitsu, Kazuyuki

2017-05-01

Autophagy is one of the major cellular processes of recycling of proteins, metabolites and intracellular organelles, and plays crucial roles in the regulation of innate immunity, stress responses and programmed cell death (PCD) in many eukaryotes. It is also essential in development and sexual reproduction in many animals. In plants, although autophagy-deficient mutants of Arabidopsis thaliana show phenotypes in abiotic and biotic stress responses, their life cycle seems normal and thus little had been known until recently about the roles of autophagy in development and reproduction. Rice mutants defective in autophagy show sporophytic male sterility and immature pollens, indicating crucial roles of autophagy during pollen maturation. Enzymatic production of reactive oxygen species (ROS) by respiratory burst oxidase homologues (Rbohs) play multiple roles in regulating anther development, pollen tube elongation and fertilization. Significance of autophagy and ROS in the regulation of PCD of transient cells during plant sexual reproduction is discussed in comparison with animals.

Healthcare and development: a dialog with the thinking of Celso Furtado.

PubMed

Costa, Laís Silveira; Bahia, Ligia; Braga, Patrícia Seixas da Costa

2017-07-01

Understanding that conditions of health are dependent on more general nationwide factors relating to the level of development means admitting that 'sectorization' of health service is something that tends to limit the formation of knowledge. It also points to the importance of investigating the relationship between health and development, including issues about the processes that feed the persistence of the polarization between modernization and exclusion which has been a history of Brazil's contemporary development. This paper, based on a review of the literature, aims to look more deeply at the structural conditioning factors of the relationship between health and development, and their reproduction in the formation of contemporary knowledge, based on a dialog with the ideas of Celso Furtado. It concludes that a 'virtuous' articulation between health and development calls for policies that are able to reconcile the antagonistic factors represented by the interests of capitalism, and the interests of social wellbeing, in a harmonious co-existence. In Furtado's conception, this would be possible, if the process of social homogenization is correlated with an efficient production system that has a degree of technological autonomy.

Comparative morphology, biology and histology of reproductive development in three lines of Manihot esculenta Crantz (Euphorbiaceae: Crotonoideae).

PubMed

Perera, P I P; Quintero, M; Dedicova, B; Kularatne, J D J S; Ceballos, H

2013-01-01

Cassava (Manihot esculenta), a major food staple in the tropics and subtropics, thrives even in environments undergoing threatening climate change. To satisfy the increasing demand for crop improvement and overcome the limitations of conventional breeding, the introduction of inbreeding techniques such as the production of doubled haploid lines via androgenesis or gynogenesis offers advantages. However, comprehensive studies on cassava flower bud biology or structural development are lacking and precise structural and biological information is a prerequisite to enhance the efficiency of these techniques. The floral biology of three selected cassava lines was studied, focusing on morphology, phenology and pollen biology (quantity, viability and dimorphism). Histological studies were also conducted on microsporogenesis/microgametogenesis and megasporogenesis/megagameto-genesis to generate precise developmental data for these lines. Male and female cyathia have distinct developmental phases. Pollen viability was high during immature stages of plant development; however, pollen mortality was common at later stages. Pollen trimorphism in male gametophytes towards the larger or smaller pollen size, as compared with normal size, was observed. Ten characteristic events were identified in male gametogenesis and six in female gametogenesis that were correlated with flower bud diameter. Male gametophyte diameter at different developmental stages was also determined. Results indicate that the three lines did not differ significantly, except regarding a few morphological aspects such as plant height, flower colour and number of male cyathia. Pollen grains were initially viable, but viability decreased drastically at later stages of growth. Abnormal meiosis or mitosis triggered pollen trimorphism. The demonstrated sequential events of reproductive development generated valuable information at the cellular level, which will help close the current information gap for cassava improvement via breeding programmes and doubled haploid plant production.

Optimization of the development of reproductive organs celepuk jawa (otus angelinae) owl which supplemented by turmeric powder

NASA Astrophysics Data System (ADS)

Rini Saraswati, Tyas; Yuniwarti, Enny Yusuf W.; Tana, Silvan

2018-03-01

Otus angelinae is included as a protected animal because of its endangered existence. Whereas, it has many values such as for mice pest control. Therefore, this research aims to optimize the reproductive function of Otus angelinae by administering turmeric powder mixed in its feed. This study was held on a laboratory scale with two male and two female Otus angelinae three months of age. Each subject is divided into two groups: a control group and a treatment group which is treated with turmeric powder 108 mg/owl/day mixed in 30 g catfish/day for a month. The parameter observed were the development of hierarchy follicles and the ovarium weight of female Otus angelinae, whereas the testis organs and testes weight were observed for the male. Both the female’s and male’s body weight, liver weight and the length of ductus reproduction were also observed. The data was analyzed descriptively. The results showed that the administration of turmeric powder can induce the development of ovarian follicles hierarchy and the length of ductus reproduction of female Otus angelinae and also induce the development of the testes and the length of ductus reproduction of male Otus angelinae. The addition of turmeric powder increased the liver weight of the female Otus angelinae, however it does not affect the body weight.

Bringing sexual and reproductive health in the urban contexts to the forefront of the development agenda: the case for prioritizing the urban poor.

PubMed

Mberu, Blessing; Mumah, Joyce; Kabiru, Caroline; Brinton, Jessica

2014-09-01

Estimates suggest that over 90 % of population increase in the least developed countries over the next four decades will occur in urban areas. These increases will be driven both by natural population growth and rural-urban migration. Moreover, despite its status as the world's least urbanized region, the urban population in the sub-Saharan Africa region is projected to increase from under 40 % currently to over 60 % by 2050. Currently, approximately 70 % of all urban residents in the region live in slums or slum-like conditions. Sexual and reproductive health (SRH) risks for the urban poor are severe and include high rates of unwanted pregnancies, sexually transmitted infections, and poor maternal and child health outcomes. However, the links between poverty, urbanization, and reproductive health priorities are still not a major focus in the broader development agenda. Building on theoretical and empirical data, we show that SRH in urban contexts is critical to the development of healthy productive urban populations and, ultimately, the improvement of quality of life. We posit that a strategic focus on the sexual and reproductive health of urban residents will enable developing country governments achieve international goals and national targets by reducing health risks among a large and rapidly growing segment of the population. To that end, we identify key research, policy and program recommendations and strategies required for bringing sexual and reproductive health in urban contexts to the forefront of the development agenda.

Identification of High-Temperature-Responsive Genes in Cereals1[C][W

PubMed Central

Hemming, Megan N.; Walford, Sally A.; Fieg, Sarah; Dennis, Elizabeth S.; Trevaskis, Ben

2012-01-01

High temperature influences plant development and can reduce crop yields. We examined how ambient temperature influences reproductive development in the temperate cereals wheat (Triticum aestivum) and barley (Hordeum vulgare). High temperature resulted in rapid progression through reproductive development in long days, but inhibited early stages of reproductive development in short days. Activation of the long-day flowering response pathway through day-length-insensitive alleles of the PHOTOPERIOD1 gene, which result in high FLOWERING LOCUS T-like1 transcript levels, did not allow rapid early reproductive development at high temperature in short days. Furthermore, high temperature did not increase transcript levels of FLOWERING LOCUS T-like genes. These data suggest that genes or pathways other than the long-day response pathway mediate developmental responses to high temperature in cereals. Transcriptome analyses suggested a possible role for vernalization-responsive genes in the developmental response to high temperature. The MADS-box floral repressor HvODDSOC2 is expressed at elevated levels at high temperature in short days, and might contribute to the inhibition of early reproductive development under these conditions. FLOWERING PROMOTING FACTOR1-like, RNase-S-like genes, and VER2-like genes were also identified as candidates for high-temperature-responsive developmental regulators. Overall, these data suggest that rising temperatures might elicit different developmental responses in cereal crops at different latitudes or times of year, due to the interaction between temperature and day length. Additionally, we suggest that different developmental regulators might mediate the response to high temperature in cereals compared to Arabidopsis (Arabidopsis thaliana). PMID:22279145

The Response of the Alpine Dwarf Shrub Salix herbacea to Altered Snowmelt Timing: Lessons from a Multi-Site Transplant Experiment.

PubMed

Sedlacek, Janosch; Wheeler, Julia A; Cortés, Andrés J; Bossdorf, Oliver; Hoch, Guenter; Lexer, Christian; Wipf, Sonja; Karrenberg, Sophie; van Kleunen, Mark; Rixen, Christian

2015-01-01

Climate change is altering spring snowmelt patterns in alpine and arctic ecosystems, and these changes may alter plant phenology, growth and reproduction. To predict how alpine plants respond to shifts in snowmelt timing, we need to understand trait plasticity, its effects on growth and reproduction, and the degree to which plants experience a home-site advantage. We tested how the common, long-lived dwarf shrub Salix herbacea responded to changing spring snowmelt time by reciprocally transplanting turfs of S. herbacea between early-exposure ridge and late-exposure snowbed microhabitats. After the transplant, we monitored phenological, morphological and fitness traits, as well as leaf damage, during two growing seasons. Salix herbacea leafed out earlier, but had a longer development time and produced smaller leaves on ridges relative to snowbeds. Longer phenological development times and smaller leaves were associated with reduced sexual reproduction on ridges. On snowbeds, larger leaves and intermediate development times were associated with increased clonal reproduction. Clonal and sexual reproduction showed no response to altered snowmelt time. We found no home-site advantage in terms of sexual and clonal reproduction. Leaf damage probability depended on snowmelt and thus exposure period, but had no short-term effect on fitness traits. We conclude that the studied populations of S. herbacea can respond to shifts in snowmelt by plastic changes in phenology and leaf size, while maintaining levels of clonal and sexual reproduction. The lack of a home-site advantage suggests that S. herbacea may not be adapted to different microhabitats. The studied populations are thus unlikely to react to climate change by rapid adaptation, but their responses will also not be constrained by small-scale local adaptation. In the short term, snowbed plants may persist due to high stem densities. However, in the long term, reduction in leaf size and flowering, a longer phenological development time and increased exposure to damage may decrease overall performance of S. herbacea under earlier snowmelt.

Characterization and differential expression of three GnRH forms during reproductive development in cultured turbot Schophthalmus maximus

NASA Astrophysics Data System (ADS)

Zhao, Chunyan; Xu, Shihong; Feng, Chengcheng; Liu, Yifan; Yang, Yang; Wang, Yanfeng; Xiao, Yongshuang; Song, Zongcheng; Liu, Qinghua; Li, Jun

2017-10-01

Turbots (Schophthalmus maximus), one of the most important economic marine flatfish species, fail to undergo final spawning and spermiation naturally under artificial farming conditions. In vertebrates, reproduction is regulated by the brain-pituitary-gonadal axis (BPG-axis), and gonadotropin releasing hormone (GnRH) is one of its key components. Therefore, to better understand the physiology of reproduction in the turbot, three of the genes encoding GnRH subtypes—sbGnRH, cGnRH-II and sGnRH—were cloned and sequenced by isolating the cDNA sequences. The localizations and patterns of expression of their mRNAs were also evaluated during seasonal gonadal development. All three mRNAs were expressed abundantly in the brain; sbGnRH and sGnRH mRNAs were also detected in the gonads and pituitary gland, and sbGnRH expression was much higher than that of sGnRH, indicating the critical role of sbGnRH in regulating the BPG-axis. Moreover, the brain expression patterns of sbGnRH and sGnRH mRNAs showed an increased trend during gonadal development, peaking in mature stages. This indicated the direct regulation of gonadal development by the GnRH system. In addition, cGnRH-II mRNA expression showed no significant variations, suggesting that cGnRH-II is not critically involved in the control of reproduction. Further, the mRNA abundances of the three GnRH forms in the breeding season were significantly higher than those in immature and post-breeding stages in all analyzed brain areas. Therefore, we propose that sbGnRH is the most important hormone for the regulation of reproduction in turbot via the BPG-axis. These results will help in better understanding the reproductive endocrine mechanisms of turbots and lay the groundwork for additional studies aimed at comparing the reproductive physiology of wild individuals with those raised under artificial conditions.