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Journal articles on the topic 'Reproductive stages'
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1
Clark, Nathaniel L., Jan E. Aagaard, and Willie J. Swanson. "Evolution of reproductive proteins from animals and plants." Reproduction 131, no. 1 (2006): 11–22. http://dx.doi.org/10.1530/rep.1.00357.
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Sexual reproduction is a fundamental biological process common among eukaryotes. Because of the significance of reproductive proteins to fitness, the diversity and rapid divergence of proteins acting at many stages of reproduction is surprising and suggests a role of adaptive diversification in reproductive protein evolution. Here we review the evolution of reproductive proteins acting at different stages of reproduction among animals and plants, emphasizing common patterns. Although we are just beginning to understand these patterns, by making comparisons among stages of reproduction for diverse organisms we can begin to understand the selective forces driving reproductive protein diversity and the functional consequences of reproductive protein evolution.
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Escarré, Josep, Claudie Houssard, and Jean Paul Briane. "Évolution du rapport des sexes de populations de Rumex acetosella le long d'une succession postculturale." Canadian Journal of Botany 65, no. 12 (1987): 2668–75. http://dx.doi.org/10.1139/b87-357.
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The sex ratios of natural populations of Rumex acetosella L. have been recorded during two growing seasons, along a successional gradient of abandoned agricultural fields of various ages (from 6 months to 15 years old), south of Paris. At the same time, male and female ramets have been collected to determine the resource allocation pattern of the different organs. We have observed that females of Rumex acetosella L. were more frequent than males at the younger stages, and that males predominated at the older ones. Concomitantly, there was a decrease in aboveground biomass and in the reproductive effort of the two sexes in the field, with increasing community maturity. The decrease in reproductive effort was confirmed, in controlled conditions, in the female genets only. Females always produced a higher reproductive effort and a higher aboveground biomass than males, which may explain why they were more abundant in the younger successional stages. Otherwise, our results show that sexual reproduction represented a high energetic cost which tended to consume root resources. Females, and mainly those of the younger stages which presented a high reproductive effort, may suffer more than males. The latter, which were more vigorous in vegetative reproduction and less affected by flower production than females, prevailed at older stages.
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Victoria, A. Vekhnik, Ruf Thomas, and Bieber Claudia. "A Review on the Edible dormouse reproduction (Glis glis Linnaeus, 1766)." Journal of Wildlife and Biodiversity 6, Special issue (2022): 28–47. https://doi.org/10.5281/zenodo.7338112.
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The reproduction of the edible dormouse has a unique pattern. A characteristic feature of its reproductive ecology is the regular occurrence of reproductive failure years. This has been observed throughout the entire distribution range. Reproduction failure has different nature in eastern and western parts of the distributional range, depending on the tree stand composition. In the central and western parts of the area, the whole population and thus males and females do not invest in reproduction, if the yielding of broad-leaved tree species, mainly beech, is missing. During the years of beech mast failures, already most males remain reproductively inactive. The gonads remain in a prepuberty state, which is a typical pattern during hibernation in this species. In the eastern parts of the distribution area, reproductive success is determined mainly by females. The main factor is the appearance of oak sets, when the vast majority of female dormice are usually already pregnant. In years of reproductive failure, mating and pregnancy are observed. However, due to damage of the seed ripening the resorption of all embryos can be observed in dormice. In reproductive years, the litter size varies within wide limits (1-11). Several females can rear their offspring together, most likely the mothers are related. The periodicity of reproduction stages depends on the duration of the active period in different regions, sometimes showing a shift of up to two months. Costs of reproduction are revealed for males during and even before the mating period.
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Tkachenko, L. V., I. A. Gritsenko, K. Yu Tikhaeva, et al. "Abortion: reproductive choice or loss of reproduction?" Medical alphabet, no. 8 (June 11, 2021): 44–48. http://dx.doi.org/10.33667/2078-5631-2021-8-44-48.
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This literature review of articles devoted to the problem of abortion and pre-abortion counseling has been carried out. The legal features of the development of the right to abortion at the request of a woman are outlined. The main stages in the development of the concept of perinatal psychology and pre-abortion counseling are described. The procedure for conducting pre-abortion counseling in the Russian Federation has been studied. The effectiveness of the existing algorithm was assessed and the prospects for further research aimed at studying and improving the effectiveness of pre-abortion counseling were outlined.
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Chia, Tet-Fatt, and Choy-Sin Hew. "Effects of Floral Excision on Reversion from Reproductive to Vegetative Development in Strawberry." HortScience 22, no. 4 (1987): 672–73. http://dx.doi.org/10.21273/hortsci.22.4.672.
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Abstract In strawberry, vegetative reproduction occurs through runners or side shoots. In our studies it was possible to produce plantlets from reproductive structures through floral excision. In this report, we describe the induction, from a reproductive structure, of successive developmental stages leading to complete plant formation.
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Yahya AM, Floos. "Histological characterization of sexual reproduction in the coral Pocillopora damicornis (Coelenterata: Scleractinia) from the Red Sea." Open Journal of Biological Sciences 7, no. 1 (2022): 7–1. http://dx.doi.org/10.17352/ojbs.000030.
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The scleractinian coral is common along the Red Sea coast, and its reproductive mode and period of reproduction were assessed using histological preparations. the sexuality, and reproductive mod timing of reproductive of pocillopora damicornis from adjacent to the fringing reefs of the Ubhur Creek in the Red Sea, were assessed using a serial histological section. Sexual reproduction in pocillopora damicornis a shallow water hermatypic coral was studied from December 2011 to November 2012. pocillopora damicornis is a simultaneous hermaphrodite with ovary and testis in the project into the body cavity on the same mesentery. Sperm and eggs were usually released simultaneously from the same polyp. The onset of the reproductive period of pocillopora damicornis was found to be limited (April to May). In the number of eggs and testes observed in this period, the gonads were found in the polyps. The pocillopora damicornis egg size ranged from 49.80 µm (in March) to 125.0 µm (in May). Four stages were chosen, to reflect very immature ovaries, the early stages of oocyte development, ova near maturity, and mature ova, and also four distinct stages of sperm development were identified. The state of gonads development (eg. testis and eggs) was measured by a calibrated eyepiece micrometer of a compound light microscope. Zooxanthellae were presented in the mature oocytes in pocillopora damicornis. This study aimed to examine the reproduction mode and timing of pocillopora damicornis.
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Birget, Philip L. G., Charlotte Repton, Aidan J. O'Donnell, Petra Schneider, and Sarah E. Reece. "Phenotypic plasticity in reproductive effort: malaria parasites respond to resource availability." Proceedings of the Royal Society B: Biological Sciences 284, no. 1860 (2017): 20171229. http://dx.doi.org/10.1098/rspb.2017.1229.
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The trade-off between survival and reproduction is fundamental in the life history of all sexually reproducing organisms. This includes malaria parasites, which rely on asexually replicating stages for within-host survival and on sexually reproducing stages (gametocytes) for between-host transmission. The proportion of asexual stages that form gametocytes (reproductive effort) varies during infections—i.e. is phenotypically plastic—in response to changes in a number of within-host factors, including anaemia. However, how the density and age structure of red blood cell (RBC) resources shape plasticity in reproductive effort and impacts upon parasite fitness is controversial. Here, we examine how and why the rodent malaria parasite Plasmodium chabaudi alters its reproductive effort in response to experimental perturbations of the density and age structure of RBCs. We show that all four of the genotypes studied increase reproductive effort when the proportion of RBCs that are immature is elevated during host anaemia, and that the responses of the genotypes differ. We propose that anaemia (counterintuitively) generates a resource-rich environment in which parasites can afford to allocate more energy to reproduction (i.e. transmission) and that anaemia also exposes genetic variation to selection. From an applied perspective, adaptive plasticity in parasite reproductive effort could explain the maintenance of genetic variation for virulence and why anaemia is often observed as a risk factor for transmission in human infections.
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Ulrich, Michael R., and Leah R. Fowler. "Continuous Reproductive Surveillance." Journal of Law, Medicine & Ethics 51, no. 3 (2023): 570–74. http://dx.doi.org/10.1017/jme.2023.107.
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AbstractThe Dobbs opinion emphasizes that the state’s interest in the fetus extends to “all stages of development.” This essay briefly explores whether state legislators, agencies, and courts could use the “all stages of development” language to expand reproductive surveillance by using novel developments in consumer health technologies to augment those efforts.
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Oliveira Neto, C. F., A. K. S. Lobato, R. C. L. Costa, et al. "Nitrogen compounds and enzyme activities in sorghum induced to water deficit during three stages." Plant, Soil and Environment 55, No. 6 (2009): 238–44. http://dx.doi.org/10.17221/84/2009-pse.
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The aim of this study was to evaluate and explicate the changes in the nitrogen compounds and enzyme activities in <I>Sorghum bicolor</I> plants (cv. BR-700) submitted to water deficit during vegetative, reproductive and maturation stages. The experimental design used was entirely randomized in factorial scheme, with two conditions (control and stress) combined with three stages (vegetative, reproductive and maturation). The nitrate level was increased at 180.6, 72.9 and 78.9% during the vegetative, reproductive and maturation stages, respectively. The total soluble amino acids and glycinebetaine increased only during vegetative and reproductive stages, if compared with control plants. However, besides protein levels during all stages, significant reductions were reported in nitrate reductase and glutamine synthetase activities; free ammonium presented decreases at 37.3 and 77.6% in vegetative and reproductive stages, respectively, when compared with control plants.
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Pang, Tin Yau. "On age-specific selection and extensive lifespan beyond menopause." Royal Society Open Science 7, no. 5 (2020): 191972. http://dx.doi.org/10.1098/rsos.191972.
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Standard evolutionary theory of ageing predicts weaker purifying selection on genes critical to later life stages. Prolonged post-reproductive lifespan (PPRLS), observed only in a few species like humans, is likely a result of disparate relaxation of purifying selection on survival and reproduction in late life stages. While the exact origin of PPRLS is under debate, many researchers agree on hypotheses like mother-care and grandmother-care, which ascribe PPRLS to investment into future generations—provision to one’s descendants to enhance their overall reproductive success. Here, we simulate an agent-based model, which properly accounts for age-specific selection, to examine how different investment strategies affect the strength of purifying selection on survival and reproduction. We observed in the simulations that investment strategies that allow a female individual to remain contributive to its own descendants (infants and adults) at late life stages may lead to differential relaxation of selection on survival and reproduction, and incur the adaptive evolution of PPRLS.
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Vézina, François, and Katrina G. Salvante. "Behavioral and physiological flexibility are used by birds to manage energy and support investment in the early stages of reproduction." Current Zoology 56, no. 6 (2010): 767–92. http://dx.doi.org/10.1093/czoolo/56.6.767.
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Abstract Interest in phenotypic flexibility has increased dramatically over the last decade, but flexibility during reproduction has received relatively little attention from avian scientists, despite its possible impact on fitness. Because most avian species maintain atrophied reproductive organs when not active, reproduction in birds requires major tissue remodeling in preparation for breeding. Females undergo rapid (days) recrudescence and regression of their reproductive organs at each breeding attempt, while males grow their organs ahead of time at a much slower rate (weeks) and may maintain them at maximal size throughout the breeding season. Reproduction is associated with significant metabolic costs. Egg production leads to a 22%-27% increase in resting metabolic rate (RMR) over non-reproductive values. This is partly due to the activity of the oviduct, an organ that may allow females to adjust reproductive investment by modulating egg size and quality. In males, gonadal recrudescence may lead to a 30% increase in RMR, but the data are inconsistent and general conclusions regarding energetic costs of reproduction in males will require more research. Recent studies on captive female zebra finches describe the impacts of these costs on daily energy budgets and highlight the strategies used by birds to maintain their investment in reproduction when energy is limited. Whenever possible, birds use behavioral flexibility as a first means of saving energy. Decreasing locomotor activity saves energy during challenges such as egg production or exposure to cold temperatures and is an efficient way to buffer variation in individual daily energy budgets. However, when behavioral flexibility is not possible, birds must rely on flexibility at the physiological level to meet energy demands. In zebra finches breeding in the cold, this results in a reduced pace of laying, likely due to down-regulation of both reproductive and non-reproductive function, allowing females to defend minimal egg size and maintain reproductive success. More research involving a range of species in captive and free-living conditions is needed to determine how phenotypic flexibility during tissue remodeling and early reproductive investment translates to natural conditions and affects fitness.
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Reutemann, Anna Verena, Ana Isabel Honfi, Piyal Karunarathne, Fabiana Eckers, Diego Hernan Hojsgaard, and Eric Javier Martínez. "Variation of Residual Sexuality Rates along Reproductive Development in Apomictic Tetraploids of Paspalum." Plants 11, no. 13 (2022): 1639. http://dx.doi.org/10.3390/plants11131639.
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Most apomictic plants are facultative, maintaining the ability to reproduce sexually at different frequencies depending on the taxa, ploidy, and reproductive stage. In this context, Paspalum species are good model systems for studies evaluating the varying levels of apomixis expression. We aimed to identify, in apomictic tetraploid Paspalum species, the degree of apomixis and residual sexuality in three stages of reproductive development, and if their expression varies along them in order to predict their realized impact on the genetic diversity of future generations. Three main stages in the reproductive development (i.e., ovule, seed, and progeny) were studied in tetraploids from populations of P. cromyorhizon and P. maculosum. Mature ovules were studied using cytoembryological analysis, seeds by flow cytometry, and progeny tests with molecular markers. The expression of sexuality and apomixis was compared in each stage. We observed a decline in expression of sexual reproduction through the consecutive stages, jointly with an increase of apomixis expression. Both species showed at least one tetraploid plant capable of producing progeny by sexual means. These small rates of sexually originated progeny prove the ability of apomictic plants to produce low levels of genetic variation through rare events of sexuality. This study also demonstrates the importance of analyzing different reproductive stages in order to get a whole picture of the reproductive outcomes in plant evolution.
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Kovaleva, E. V. "Theoretical aspects of resource reproduction in agriculture." Machinery and Equipment for Rural Area, no. 1 (January 22, 2021): 2–6. http://dx.doi.org/10.33267/2072-9642-2021-1-2-6.
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The theoretical provisions of the reproductive process at different stages of development are discussed. The need for the reproduction of production relations, but not only the productive forces, is identified. The characteristics of the reproductive process being inherent in it at the present stage are formulated, while maintaining a cyclical nature taking into account the changing quality.
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Menzies, Brandon R., Thomas B. Hildebrandt, and Marilyn B. Renfree. "Unique reproductive strategy in the swamp wallaby." Proceedings of the National Academy of Sciences 117, no. 11 (2020): 5938–42. http://dx.doi.org/10.1073/pnas.1922678117.
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Reproduction in mammals requires distinct cycles of ovulation, fertilization, pregnancy, and lactation often interspersed with periods of anoestrus when breeding does not occur. Macropodids, the largest extant species of marsupials, the kangaroos and wallabies, have a very different reproductive strategy to most eutherian mammals whereby young are born at a highly altricial stage of development with the majority of development occurring over a lengthy lactation period. Furthermore, the timings of ovulation and birth in some species occurs within a very short interval of each other (sometimes hours). Female swamp wallabies have an oestrous cycle shorter than their pregnancy length and were, therefore, speculated to mate and form a new embryo before birth thereby supporting two conceptuses at different stages of pregnancy. To confirm this, we used high-resolution ultrasound to monitor reproduction in swamp wallabies during pregnancy. Here, we show that females ovulate, mate, and form a new embryo prepartum while still carrying a full-term fetus in the contralateral uterus. This embryo enters embryonic diapause until the newborn leaves the pouch 9 mo later. Thus, combined with embryonic diapause, females are continuously pregnant and lactating at the same time throughout their reproductive life, a unique reproductive strategy that completely blurs the normal staged system of reproduction in mammals.
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Rangel, BS, N. Hammerschlag, JA Sulikowski, and RG Moreira. "Dietary and reproductive biomarkers in a generalist apex predator reveal differences in nutritional ecology across life stages." Marine Ecology Progress Series 664 (April 15, 2021): 149–63. http://dx.doi.org/10.3354/meps13640.
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Knowledge of the nutritional requirements of apex predators is key for determining ecological interactions. However, an understanding of how diet is influenced by reproduction, and the consequences of foraging variation on the nutritional status of a predator, is limited. Here, we used short-term dietary markers (plasma and whole-blood fatty acids) integrated with reproductive hormones (17β-estradiol and testosterone) and ultrasonography as a non-lethal approach to investigate the effect of life stage on nutritional status and trophic dynamics of female tiger sharks Galeocerdo cuvier. Despite their generalist feeding behavior, female tiger sharks fed on different food sources and/or modulated their fatty acid metabolism depending on the reproductive context. This suggests some adjustment in their nutritional requirements associated with changes in their reproductive state. Plasma and whole-blood fatty acids indicated distinct dietary sources across life stages, with a high dependence on coastal/benthic food resources during juvenile life stages, and on pelagic/oceanic and reef-associated food resources during adult life stages. Higher percentages of highly unsaturated omega-3 fatty acids found in females during their reproductive cycles suggest the dependency on these fatty acids as a source of metabolic energy during reproduction. A high percentage of arachidonic acid (ARA) found in plasma of gravid females suggests the possibility of a selective diet of ARA-rich prey species and/or selective mobilization of ARA from stored energy during gestation. Based on our findings, we propose a conceptual model of expected changes in nutritional and trophic markers across life stages of female tiger sharks.
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Mitchell, J. H., S. L. Zulkafli, J. Bosse, et al. "Rice-cold tolerance across reproductive stages." Crop and Pasture Science 67, no. 8 (2016): 823. http://dx.doi.org/10.1071/cp15331.
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Cold temperature stress at the reproductive stage, particularly at booting and flowering stages can cause significant reductions in rice (Oryza sativa L.) yield particularly at high latitudes and elevation. Although genotypic variation for cold tolerance is known to exist, the tolerance mechanisms and genotypic consistency across the stages are yet to be understood for segregating populations. Three experiments were conducted under controlled temperature glasshouse conditions to determine floral characteristics that were associated with cold tolerance at the flowering stage and to determine genotypic consistency at the booting and flowering stages. Twenty F5 Reiziq × Lijiangheigu lines from two extreme phenotypic bulks selected for cold tolerance at booting stage in the F2 generation were utilised. Spikelet sterility under cold stress at booting was significantly correlated with spikelet sterility under cold stress at flowering (r = 0.62**) with five lines identified as cold tolerant across reproductive stages. There was also a positive correlation (r = 0.47*) between spikelet sterility under cold stress at booting at the F5 and at the F2 generation. The quantitative trait loci (QTL; qLTSPKST10.1) previously identified on chromosome 10 contributing to spikelet sterility within the F2 generation, was also identified in the F5 generation. Additionally, genomic regions displaying significant segregation between the progenies contrasting for their cold tolerance response phenotype were identified on chromosomes 5 and 7 with Lijiangheigu as allelic donor and an estimated reduction in spikelet sterility of 25% and 27%, respectively. Although genotypic variation in spikelet sterility at the booting stage was not related to the development rate for heading or flowering, those cold-tolerant genotypes at the flowering stage were the quickest to complete flowering. Cold-tolerant genotypes at the flowering stage had larger numbers of dehisced anthers and subsequently pollen number on stigma, which contributed to reduced spikelet sterility. It is concluded that enhanced anther dehiscence plays a significant role in improved cold tolerance at the flowering stage.
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Soules, Michael R., Sherry Sherman, Estella Parrott, et al. "Stages of Reproductive Aging Workshop (STRAW)." Journal of Women's Health & Gender-Based Medicine 10, no. 9 (2001): 843–48. http://dx.doi.org/10.1089/152460901753285732.
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Na, Mi, Cai Fu, Zhang Yushu, Ji Ruipeng, Zhang Shujie, and Wang Yang. "Differential responses of maize yield to drought at vegetative and reproductive stages." Plant, Soil and Environment 64, No. 6 (2018): 260–67. http://dx.doi.org/10.17221/141/2018-pse.
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Determining the effects of progressive drought (PD) on dry matter production, partitioning, and grain yield of maize will help in designing a suitable strategy for water management. Though influences of drought on maize growth and development have been investigated extensively, few of them focused on the effects of different duration and occurrence stage of PD on yield formation of maize. Six variations of PD, in the form of withholding irrigation for varying lengths of time from jointing or tasselling, were tested in the field, using a mobile rain shelter, in terms of their effects on aboveground biomass accumulation, partitioning, and grain yield in 2015–2016. The results showed that grain yield was significantly reduced by PD during either vegetative or reproductive stage, and the reduction in grain yield from reproductive PD (41.6–46.6%) was greater than that from vegetative PD (18.6–26.2%). The decrease in grain yield was largely caused by the decrease in kernels per ear (r<sup>2</sup> = 0.88, P &lt; 0.001). This research implied that guaranteeing water supply for maize during reproductive stage is crucially important to avoid the reduction in kernels per ear and grain yield.
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Wadood, Armughan Ahmed, and Xiquan Zhang. "The Omics Revolution in Understanding Chicken Reproduction: A Comprehensive Review." Current Issues in Molecular Biology 46, no. 6 (2024): 6248–66. http://dx.doi.org/10.3390/cimb46060373.
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Omics approaches have significantly contributed to our understanding of several aspects of chicken reproduction. This review paper gives an overview of the use of omics technologies such as genomics, transcriptomics, proteomics, and metabolomics to elucidate the mechanisms of chicken reproduction. Genomics has transformed the study of chicken reproduction by allowing the examination of the full genetic makeup of chickens, resulting in the discovery of genes associated with reproductive features and disorders. Transcriptomics has provided insights into the gene expression patterns and regulatory mechanisms involved in reproductive processes, allowing for a better knowledge of developmental stages and hormone regulation. Furthermore, proteomics has made it easier to identify and quantify the proteins involved in reproductive physiology to better understand the molecular mechanisms driving fertility, embryonic development, and egg quality. Metabolomics has emerged as a useful technique for understanding the metabolic pathways and biomarkers linked to reproductive performance, providing vital insights for enhancing breeding tactics and reproductive health. The integration of omics data has resulted in the identification of critical molecular pathways and biomarkers linked with chicken reproductive features, providing the opportunity for targeted genetic selection and improved reproductive management approaches. Furthermore, omics technologies have helped to create biomarkers for fertility and embryonic viability, providing the poultry sector with tools for effective breeding and reproductive health management. Finally, omics technologies have greatly improved our understanding of chicken reproduction by revealing the molecular complexities that underpin reproductive processes.
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Langvatn, Rolf. "Analysis of ovaries in studies of reproduction in red deer (Cervus elaphus, L.): Application and limitations." Rangifer 12, no. 3 (1992): 67. http://dx.doi.org/10.7557/2.12.2.1025.
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A set of definitions for luteal structures and their regressing stages in red deer ovaries is suggested. Structural characteristics in ovaries pertaining to reproductive analysis is compiled from relevant literature and combined with observations from the present study. Luteal structures and their regressing stages may be useful in assessment of reproductive status and history, provided the analysis is performed with a full understanding of the limitations of the criteria and the methodological approach. Primary corpus luteum (PCL), corpus luteum of pregnancy (CLV), and corpus rubrum (CR) are the most important structures in the quantitative analysis of reproduction, and they may be identified at a macroscopic level. However, confusion with other structures is conceiveable, and for an accurate analysis microscopic -examination of histological preparations is necessary. Different processing and analysing procedures are compared, illustrating differences in resolution and precision, especially in retrospective analysis. Data from hinds with known reproductive history indicate limitations and potential in analysis of ovaries as a technique to assess reproductive status and history in red deer.
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Gomiero, LM, L. Garuana, and FMS Braga. "Reproduction of Oligosarcus hepsetus (Cuvier, 1829) (Characiforms) in the Serra do Mar State Park, São Paulo, Brazil." Brazilian Journal of Biology 68, no. 1 (2008): 187–92. http://dx.doi.org/10.1590/s1519-69842008000100027.
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The purpose of this study was to characterize the reproduction of Oligosarcus hepsetus in the Grande river (Santa Virginia Unit - Serra do Mar State Park) based on the reproductive period, length of first gonadal maturation for both sexes, sexual proportion, oocyte development, type of spawn and fecundity. The Grande river was sampled monthly from January through December 2004. The numerical frequency of the stages of maturity and the volumetric method were utilized to determine the reproductive period and fecundity, respectively. The reproduction of Oligosarcus hepsetus was characterized by a long period, relatively low fecundity, precocious length of first gonadal maturation and parceled spawning.
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Brito, M. F. G., and N. Bazzoli. "Reproduction of the surubim catfish (Pisces, Pimelodidae) in the São Francisco River, Pirapora Region, Minas Gerais, Brazil." Arquivo Brasileiro de Medicina Veterinária e Zootecnia 55, no. 5 (2003): 624–33. http://dx.doi.org/10.1590/s0102-09352003000500018.
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The reproductive biology of the surubim, P. coruscans of the São Francisco River, in the Pirapora region was studied from December/98 to November/99. Reproduction occurred between October and January with high frequency of fishes in the advanced ripening/mature and spawned/spent stages along with higher values of the gonadosomatic index. Macroscopic and microscopic analyses indicated that P. coruscans presents total spawning. The reproductive period coincided with highest rainfall and water turbidity values in the region. The smallest male captured had a total length of 63.3cm and the smallest female 92.0cm in total length. The largest male in the maturation stage was recorded to be 97.0cm and the largest female 144.1cm in total length. Surubim were more frequently captured than females, at a proportion of approximately one female to three males. The gonadosomatic, hepatosomatic, stomach repletion, and coelomic fat indexes, as well as the condition factor were related to stages of the reproductive cycle.
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Ma, Xinwei, Zhao Su, and Hong Ma. "Molecular genetic analyses of abiotic stress responses during plant reproductive development." Journal of Experimental Botany 71, no. 10 (2020): 2870–85. http://dx.doi.org/10.1093/jxb/eraa089.
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Abstract Plant responses to abiotic stresses during vegetative growth have been extensively studied for many years. Daily environmental fluctuations can have dramatic effects on plant vegetative growth at multiple levels, resulting in molecular, cellular, physiological, and morphological changes. Plants are even more sensitive to environmental changes during reproductive stages. However, much less is known about how plants respond to abiotic stresses during reproduction. Fortunately, recent advances in this field have begun to provide clues about these important processes, which promise further understanding and a potential contribution to maximize crop yield under adverse environments. Here we summarize information from several plants, focusing on the possible mechanisms that plants use to cope with different types of abiotic stresses during reproductive development, and present a tentative molecular portrait of plant acclimation during reproductive stages. Additionally, we discuss strategies that plants use to balance between survival and productivity, with some comparison among different plants that have adapted to distinct environments.
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Martin, R. J., R. N. Gillespie, and T. L. Knight. "Prediction of reproductive growth stages in barley." New Zealand Journal of Crop and Horticultural Science 21, no. 1 (1993): 73–84. http://dx.doi.org/10.1080/01140671.1993.9513749.
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Begum, Shahina, Jean J. Schensul, Saritha Nair, and Balaiah Donta. "Initiating Smokeless Tobacco Use across Reproductive Stages." Asian Pacific Journal of Cancer Prevention 16, no. 17 (2015): 7547–54. http://dx.doi.org/10.7314/apjcp.2015.16.17.7547.
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Hanus, Robert, Vladimír Vrkoslav, Ivan Hrdý, Josef Cvačka, and Jan Šobotník. "Beyond cuticular hydrocarbons: evidence of proteinaceous secretion specific to termite kings and queens." Proceedings of the Royal Society B: Biological Sciences 277, no. 1684 (2009): 995–1002. http://dx.doi.org/10.1098/rspb.2009.1857.
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In 1959, P. Karlson and M. Lüscher introduced the term ‘pheromone’, broadly used nowadays for various chemicals involved in intraspecific communication. To demonstrate the term, they depicted the situation in termite societies, where king and queen inhibit the reproduction of nest-mates by an unknown chemical substance. Paradoxically, half a century later, neither the source nor the chemical identity of this ‘royal’ pheromone is known. In this study, we report for the first time the secretion of polar compounds of proteinaceous origin by functional reproductives in three termite species, Prorhinotermes simplex , Reticulitermes santonensis and Kalotermes flavicollis . Aqueous washes of functional reproductives contained sex-specific proteinaceous compounds, virtually absent in non-reproducing stages. Moreover, the presence of these compounds was clearly correlated with the age of reproductives and their reproductive status. We discuss the putative function of these substances in termite caste recognition and regulation.
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Ali, Sayid, Tamrat Degefa, and Alemayehu Lemma. "Morphometrical study of the reproductive tract in Boran (Bos indicus) heifers in Ethiopia." Ethiopian Veterinary Journal 25, no. 2 (2021): 1–13. http://dx.doi.org/10.4314/evj.v25i2.1.
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Boran breed is the most suitable type of cattle breed for arid and semi-arid regions of Ethiopia due to their adaptive characteristics. Understanding their reproductive anatomy is important for successful reproductive management and has many implications for the application of assisted reproductive technology, and interpretation of physiological changes at different stages of their reproductive cycle. In this study, data of the anatomical structures of the reproductive organs of 20 Boran heifers were measured and characterized at different stages of reproduction. The mean (±SE) length (L) of the vagina, cervix, and body of uterus were 13.17±2.98 cm, 7.19±1.28 cm, and 6.70±1.08cm, respectively. The mean (±SE) length of the right uterine horn and oviduct was 18.47 ±2.54 and 18.17 ±1.27cm, respectively and that of the left were 18.05±2.73 and 17.45±1.80 cm, respectively. The mean ±SE weight (W) of right and left ovaries were 2.44±1.51 gm and 2.44±1.51 gm, respectively. The mean ±SE Length x Width x Thickness of the right ovary was 2.10±0.59 x 1.75±0.35 x 0.83±0.36 and that of the left was 1.97±0.41 x 1.58±0.29 x 0.67±0.33 cm. The mean (±SE) weight of the whole reproductive organ (without the vulva) was 301.35±66.34gm. The ovarian size was influenced by the presence of the corpus luteum(CL) usually larger with its presence.
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Ferraz, Juliana F., Oliveira Rodrigo S. De, Cornélio S. Santiago, et al. "The marked dextro-dominance causes accentuated morphophysiological variations in the female reproductive organs of the bat Molossus molossus." Tissue and Cell 85 (June 12, 2023): 102245. https://doi.org/10.5281/zenodo.13490803.
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(Uploaded by Plazi for the Bat Literature Project) Molossus molossus is an insectivorous molossid bat that is important in the control of nocturnal insects. It is the nominal and the most representative species of the family. However, there are few studies about its reproduction. Thus, this study aimed to evaluate variations of its female reproductive organs during the different reproductive phases. Twenty adult females, divided into four sample groups (non-reproductive, early and advanced pregnancy and lactation), were submitted to morphological and morphometric analyses. Results show that the female reproductive system of M. molossus is composed of ovaries, a short bicornuate uterus, slightly convoluted uterine tubes and vagina. The system presents a distinct morphofunctional asymmetry, with a marked dextrodominance. The right ovaries of all analyzed groups (NON, P1, P2, and LAC) showed follicles at different stages of development, a large number of interstitial glands and a small, but persistent corpus luteum. Ovulation is simple, unilateral and preferential, occurring exclusively in the right ovary. Follicular development in the left ovary usually does not pass the secondary stage. Implantation is fundic and preferential, occurring exclusively in the right uterine horn. The placenta is formed with two distinct chorioallantoic portions, one diffuse endothe liochorial, which covers the entire uterine cavity and regresses in the final stages of pregnancy, and the principal discoidal hemochorial portion, formed in the implantation site. The uterine cervix presents a pseudostratified epithelium, while the vagina has a little keratinized stratified epithelium, which does not accentually vary in the different reproductive stages, but can disrupt and shed in some cases.
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Ferraz, Juliana F., Oliveira Rodrigo S. De, Cornélio S. Santiago, et al. "The marked dextro-dominance causes accentuated morphophysiological variations in the female reproductive organs of the bat Molossus molossus." Tissue and Cell 85 (June 7, 2023): 102245. https://doi.org/10.5281/zenodo.13490803.
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(Uploaded by Plazi for the Bat Literature Project) Molossus molossus is an insectivorous molossid bat that is important in the control of nocturnal insects. It is the nominal and the most representative species of the family. However, there are few studies about its reproduction. Thus, this study aimed to evaluate variations of its female reproductive organs during the different reproductive phases. Twenty adult females, divided into four sample groups (non-reproductive, early and advanced pregnancy and lactation), were submitted to morphological and morphometric analyses. Results show that the female reproductive system of M. molossus is composed of ovaries, a short bicornuate uterus, slightly convoluted uterine tubes and vagina. The system presents a distinct morphofunctional asymmetry, with a marked dextrodominance. The right ovaries of all analyzed groups (NON, P1, P2, and LAC) showed follicles at different stages of development, a large number of interstitial glands and a small, but persistent corpus luteum. Ovulation is simple, unilateral and preferential, occurring exclusively in the right ovary. Follicular development in the left ovary usually does not pass the secondary stage. Implantation is fundic and preferential, occurring exclusively in the right uterine horn. The placenta is formed with two distinct chorioallantoic portions, one diffuse endothe liochorial, which covers the entire uterine cavity and regresses in the final stages of pregnancy, and the principal discoidal hemochorial portion, formed in the implantation site. The uterine cervix presents a pseudostratified epithelium, while the vagina has a little keratinized stratified epithelium, which does not accentually vary in the different reproductive stages, but can disrupt and shed in some cases.
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Verdiyeva, Leyla Elman, Nailya Tofig Gurbanova, Aytan Azer Mammadova, Elmira Musallim Mammadova, and Ramil Mushfig Askerov. "TREATMENT OF ENDOMETRITIS." Deutsche internationale Zeitschrift für zeitgenössische Wissenschaft 61 (August 1, 2023): 63–65. https://doi.org/10.5281/zenodo.8204687.
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Timely detection and treatment of sick cows in the early stages of the disease will ensure rapid recovery and restoration of their reproductive ability. In the system of measures for the elimination of infertility and cow manure, accounting and analysis of reproduction is of great importance.
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Ivanova, Oksana, and Svetlana Belikova. "Assessment of the innovation ecosystem reproductive potential." E3S Web of Conferences 281 (2021): 08004. http://dx.doi.org/10.1051/e3sconf/202128108004.
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The technological development of the national economy in modern conditions is impossible without the creation of a stable innovation ecosystem, capable of a continuous process of the innovations expanded reproduction. Within the framework of the innovation ecosystem, conditions should be created not only for innovation, but also for the active introduction of innovative products. This is especially true for the construction industry, which is the engine of economic growth. In order to analyze the ability of an innovation ecosystem to reproduce innovations, the authors proposed a methodology for assessing the reproductive potential of an innovation ecosystem, which is based on the index method. A distinctive feature of the proposed methodology is the formation of a system of indicators relative to the main stages of innovation reproduction. In most scientific studies, the analysis is based on the assessment of the activities of economic entities involved in innovation. The methodology was tested at the regional level. In this case, an analysis of the industry specifics is possible. The results obtained make it possible to assess the reproductive potential of an innovation ecosystem, to identify the problematic stages in the innovations’ creation and implementation, which contributes to the possibility of using the additional levers for intensifying economic growth.
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Zhang, Jianchun, Jie Kong, Jiawang Cao, et al. "Reproductive Ability Disparity in the Pacific Whiteleg Shrimp (Penaeus vannamei): Insights from Ovarian Cellular and Molecular Levels." Biology 13, no. 4 (2024): 218. http://dx.doi.org/10.3390/biology13040218.
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The Pacific whiteleg shrimp (Penaeus vannamei) is a highly significant species in shrimp aquaculture. In the production of shrimp larvae, noticeable variations in the reproductive capacity among female individuals have been observed. Some females experience slow gonadal development, resulting in the inability to spawn, while others undergo multiple maturations and contribute to the majority of larval supply. Despite numerous studies that have been conducted on the regulatory mechanisms of ovarian development in shrimp, the factors contributing to the differences in reproductive capacity among females remain unclear. To elucidate the underlying mechanisms, this study examined the differences in the ovarian characteristics between high and low reproductive bulks at different maturity stages, focusing on the cellular and molecular levels. Transmission electron microscopy analysis revealed that the abundance of the endoplasmic reticulum, ribosomes, mitochondria, and mitochondrial cristae in oocytes of high reproductive bulk was significantly higher than that of the low reproductive bulk in the early stages of ovarian maturation (stages I and II). As the ovaries progressed to late-stage maturation (stages III and IV), differences in the internal structures of oocytes between females with different reproductive capacities gradually diminished. Transcriptome analysis identified differentially expressed genes (DEGs) related to the mitochondria between two groups, suggesting that energy production processes might play a crucial role in the observed variations in ovary development. The expression levels of the ETS homology factor (EHF) and PRDI-BF1 and RIZ homology domain containing 9 (PRDM9), which were significantly different between the two groups, were compared using qRT-PCR in individuals at different stages of ovarian maturation. The results showed a significantly higher expression of the EHF gene in the ovaries of high reproductive bulk at the II and IV maturity stages compared to the low reproductive bulk, while almost no expression was detected in the eyestalk tissue of the high reproductive bulk. The PRDM9 gene was exclusively expressed in ovarian tissue, with significantly higher expression in the ovaries of the high reproductive bulk at the four maturity stages compared to the low reproductive bulk. Fluorescence in situ hybridization further compared the expression patterns of EHF and PRDM9 in the ovaries of individuals with different fertility levels, with both genes showing stronger positive signals in the high reproductive bulk at the four ovarian stages. These findings not only contribute to our understanding of the regulatory mechanisms involved in shrimp ovarian development, but also provide valuable insights for the cultivation of new varieties aimed at improving shrimp fecundity.
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Rocha, Carolina, Eduarda De Favere, and Mariana da Silva Neri. "TÉCNICAS DE REPRODUÇÃO ASSISTIDA: ÊNFASE EM FERTILIZAÇÃO IN VITRO E INJEÇÃO INTRACITOPLASMÁTICA DE ESPERMATOZOIDES." Revista ft 28, no. 140 (2024): 18–19. http://dx.doi.org/10.69849/revistaft/pa10202411231618.
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This work sought to study the main aspects of human reproduction, addressing questions, methods and analyzing its technical processes, its indications, and the expected results in cases of severe infertility. The research includes an analysis of the stages of fertilization, and current reproductive technologies, such as in vitro fertilization (IVF), and intracytoplasmic sperm injection (ICSI) and used a literature review to demonstrate the advantages and disadvantages of each method and how Health conditions can affect reproductive capacity. It was also observed the biological processes involved, as well as the social and ethical implications. Thus, through a literature review, the work aimed to offer a comprehensive view of human reproduction, highlighting the importance of understanding the factors that affect fertility. It also sought to highlight how reproduction methods can help couples who face difficulties in searching for appropriate treatments to expand the possibilities of conception based on the various reproductive options, considering their limitations and factors such as age, health and personal circumstances.
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Khan, Muhammad Ibrahim, Muhammad Imran Khan, and Fazal Wahab. "Irisin in Reproduction: Its Roles and Therapeutic Potential in Male and Female Fertility Disorders." Biomolecules 14, no. 10 (2024): 1222. http://dx.doi.org/10.3390/biom14101222.
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The current study focused on identifying the potential of irisin in mammalian reproduction. The established role of irisin, a proteolytic product of FNDC5, in adipose tissue browning, energy metabolism, and thermogenesis suggests its role in reproductive health, often disturbed by metabolic imbalances. Various studies on mice demonstrated irisin′s role in improving spermatogenesis, sperm count, and testosterone levels by influencing the hypothalamus–pituitary–gonadal axis. Moreover, in females, there is a fluctuation in levels of irisin during critical reproductive stages, including menstrual cycles, puberty, and pregnancy. Conditions like pregnancy complications, precocious puberty, and polycystic ovary syndrome (PCOS) are found to have an association with abnormal irisin levels. The potential role of irisin in endometrial receptivity and preventing endometritis is also discussed in this review. Overall, the influence of irisin on female and male reproduction is evident from various studies. However, further research is needed to elucidate irisin mechanism in reproduction and its potential as a therapeutic or diagnostic tool for reproductive dysfunctions and infertility.
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Simoni, Maria Ester Ribeiro, Edson Bortoletto Garciov Filho, Paulo Guilherme Vasconcelos de Oliveira, Mariana Gomes do Rêgo, Fábio Hissa Vieira Hazin, and Paulo Travassos. "Reproductive biology of the mutton hamlet on the coast of Pernambuco, northeastern Brazil." Neotropical Biology and Conservation 14, no. 2 (2019): 157–68. http://dx.doi.org/10.3897/neotropical.14.e37601.
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This paper focuses on the reproductive biology of the Mutton Hamlet, Alphestesafer, a fish belonging to the family Epinephelidae, and aims to provide information on the main reproductive parameters of the species on the north coast of the state of Pernambuco, northeastern Brazil. From a total of 783 individuals, collected between March 2007 and June 2010, and from February to November 2014, the gonads of 322 fishes (235 females and 87 males) were analyzed, for the identification of sex and maturational stages. Females were more abundant and larger than males, with a sex ratio of 2.4 females: 1 male, during the reproduction season. The size at first maturity (L50) was estimated at 16.8 cm total length for females, and 16.2 cm for males. The gonadosomatic index (GSI) indicated that a reproductive cycle occurs all year round, while reproduction takes place from June to November. The fecundity of Alphestesafer ranged from 105,317 to 270,192 oocytes, averaging 173,458 oocytes. The females are more abundant than males due to the process of protogyny and also because individuals are regularly captured at growth stages above the L50, being a positive aspect for the sustainability of the fishery. According to the GSI, the species presents a split-type spawning with two peaks occurring throughout the year.
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Maruska, Karen P., and Russell D. Fernald. "Plasticity of the Reproductive Axis Caused by Social Status Change in an African Cichlid Fish: II. Testicular Gene Expression and Spermatogenesis." Endocrinology 152, no. 1 (2011): 291–302. http://dx.doi.org/10.1210/en.2010-0876.
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Abstract Reproduction in all vertebrates is controlled by the brain-pituitary-gonad (BPG) axis, which is regulated socially in males of the African cichlid fish Astatotilapia burtoni. Although social information influences GnRH1 neurons at the apex of the BPG axis, little is known about how the social environment and dominance affects the cellular and molecular composition of the testes to regulate reproductive capacity. We created an opportunity for reproductively suppressed males to ascend in status and then measured changes in gene expression and tissue morphology to discover how quickly the perception of this opportunity can influence the testes. Our results show rapid up-regulation of mRNA levels of FSH receptor and several steroid receptor subtypes in the testes during social ascent. In contrast, LH receptor was not elevated until 72 h after ascent, but this increase was coincident with elevated circulating androgens and early stages of spermatogenesis, suggesting a role in steroidogenesis. The spermatogenic potential of the testes, as measured by cellular composition, was also elevated before the overall increase in testes size. The presence of cysts at all stages of spermatogenesis, coupled with lower levels of gonadotropin and steroid receptors in subordinate males, suggests that the BPG axis and spermatogenesis are maintained at a subthreshold level in anticipation of the chance to gain a territory and become reproductively active. Our results show that the testis is stimulated extremely quickly after perception of social opportunity, presumably to allow suppressed males to rapidly achieve high reproductive success in a dynamic social environment.
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Hakberdiyeva, Shoira Tursunaliyevna Holtorayeva Laylo Ismail qizi. "REPRODUCTION AND DEVELOPMENT OF VERTEBRATES." American Journal of Advanced Scientific Research (AJASR) 2, no. 9 (2025): 201–3. https://doi.org/10.5281/zenodo.15055237.
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This article highlights the main processes and characteristicsrelated to the reproduction and development of vertebrates. It discusses the forms ofsexual reproduction, the stages of embryonic and post-embryonic development, andthe reproductive and developmental strategies across different vertebrate groups.Additionally, the article analyzes the ecological and biological factors influencingthese processes. It is a valuable resource for those studying vertebrate biology,helping to understand biodiversity and adaptability.
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ALESHKINA, OKSANA S., OLEG E. KONOVALOV, ALEXEY V. SHULAYEV, EVGENIA M. PRISTUPA, and ALEXEY V. BREUSOV. "STAGES OF REHABILITATION FOR WOMEN AFTER EARLY REPRODUCTIVE LOSS." Bulletin of Contemporary Clinical Medicine 16, no. 4 (2023): 124–31. http://dx.doi.org/10.20969/vskm.2023.16(4).124-131.
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Introduction. For all early reproductive losses, the need for restorative treatment is common. Aim. The purpose of the study is to analyze the experience of the gynecological hospital in Ryazan on a 3-stage comprehensive rehabilitation of women with early reproductive losses. Material and Methods. The development of this algorithm was carried out on the basis of an analysis of the results of research and the experience of leading research centers. A sociological survey was carried out among 128 obstetrician-gynecologists working in the gynecological department of the hospital and antenatal clinics in Ryazan. Results and discussion. The results of a sociological survey among obstetricians-gynecologists confirmed the importance of rehabilitation measures after early reproductive loss, as well as assessing the health status of women, including in terms of psycho-emotional status. At the same time, 44.8 % of respondents believed that the rehabilitation of women after early pregnancy loss should be carried out in a day hospital, 23.9% in a round-the-clock hospital, 21.6% - on an outpatient basis, 9.7% of the surveyed doctors found it difficult to answer. A description is given of the content of each of the three stages (stationary, restorative and supportive) of the developed and tested scheme of complex rehabilitation. Based on the results of the third stage, the doctor gives a comprehensive assessment of the woman’s reproductive health after the loss of pregnancy, together with the patient determines her further reproductive plan: either prescribe reliable contraception or prenatal preparation. Conclusion. Implementation The three-stage rehabilitation scheme makes it possible to provide full-scale specialized medical care for the restoration of reproductive health and psycho-emotional sphere to women with early reproductive loss, as well as to form their further reproductive plans.
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Erskine, W., F. J. Muehlbauer, and R. W. Short. "Stages of Development in Lentil." Experimental Agriculture 26, no. 3 (1990): 297–302. http://dx.doi.org/10.1017/s0014479700018457.
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SUMMARYUniform descriptions of developmental stages in crops improve communication among producers, researchers and others. This paper gives a uniform system for the description of the developmental stages of lentil that we believe is not only universally applicable to all growing environments (field or greenhouse) and to divergent cultivars, but also useful for single plants or communities of plants. Vegetative and reproductive development are described separately. Vegetative growth stages are described by counting nodes on the main stem and continuing the count up the basal primary branch to include the highest fully developed leaf. Reproductive stages Rl and R2 are based on flowering, R3 to R6 on pod and seed development, and R7 and R8 on maturation.
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Lourenço, Sofia, and Jorge Mestre Palmeirim. "Which factors regulate the reproduction of ectoparasites of temperate-zone cave-dwelling bats?" Parasitology Research 104, no. 1 (2008): 127–34. https://doi.org/10.5281/zenodo.14818026.
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(Uploaded by Plazi for the Bat Literature Project) We studied the factors which regulate the reproduction of ectoparasites of temperate-zone cavedwelling bats, using the Schreiber's bat (Miniopterus schreibersii) and its ectoparasites as a model. For this, we searched 969 bats during 2003 and 2004 at important stages of the bat yearly cycle and found four ectoparasite species regularly occurring on them: two nycteribiids (Nycteribia schmidlii and Penicillidia conspicua), one wing mite (Spinturnix psi), and one hard tick (Ixodes simplex simplex). These parasites were present throughout the yearly cycle, but their reproductive activity greatly fluctuated seasonally. Also, we found that sex, age, and reproductive status of the host strongly influenced the reproductive activity of parasites. Overall, the four parasite species had a similar reproductive pattern, reproducing more intensively during the pregnancy and nursing seasons of M. schreibersii, mainly on pregnant and juvenile bats. Moreover, parasites greatly reduced reproductive activity during winter, while bats were in deep torpor or hibernating. We conclude that reproduction in ectoparasites of M. schreibersii and of many other temperate cave-dwelling bats is mostly regulated by the reproductive cycle of their bat hosts, but also limited by roost temperatures during winter. The fact that the reproductive cycle of parasite species of such distinct taxonomic groups are similarly adjusted to that of their bat host suggests that this adjustment is a highly adaptive trait.
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Adams, Elena, Christoph Leeb, and Carsten A. Brühl. "Pesticide exposure affects reproductive capacity of common toads (Bufo bufo) in a viticultural landscape." Ecotoxicology 30, no. 2 (2021): 213–23. http://dx.doi.org/10.1007/s10646-020-02335-9.
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AbstractAmphibian populations are declining worldwide at alarming rates. Among the large variety of contributing stressors, chemical pollutants like pesticides have been identified as a major factor for this decline. Besides direct effects on aquatic and terrestrial amphibian stages, sublethal effects like impairments in reproduction can affect a population. Therefore, we investigated the reproductive capacity of common toads (Bufo bufo) in the pesticide-intensive viticultural landscape of Palatinate in Southwest Germany along a pesticide gradient. In a semi-field study, we captured reproductively active common toad pairs of five breeding ponds with different pesticide contamination level and kept them in a net cage until spawning. Toads from more contaminated ponds showed an increased fecundity (more eggs) but decreased fertilization rates (fewer hatching tadpoles) as well as lower survival rates and reduced size in Gosner stage 25, suggesting that the higher exposed populations suffer from long-term reproductive impairments. In combination with acute toxicity effects, the detected sublethal effects, which are mostly not addressed in the ecological risk assessment of pesticides, pose a serious threat on amphibian populations in agricultural landscapes.
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Bordin, Rafael O. A., Classius de Oliveira, and Raquel F. Domeniconi. "Immunolocalization of Aquaporin 1, 2, and 9 in Anuran Testis of the Neotropical Pointedbelly Frog Leptodactylus podicipinus." Current Issues in Molecular Biology 46, no. 9 (2024): 9958–69. http://dx.doi.org/10.3390/cimb46090594.
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Many anuran survival strategies involve hydric regulation, and reproduction is not different. The aquaporin (AQP) family plays an important role in water transport and regulation in many tissues, including the male gonad. The testes undergo various stages of change during the reproductive cycle, and water balance is an important factor for ensuring reproductive success. Considering the relevance of water control in testicular development in anurans and the lack of research regarding the tissue localization of AQP in the male gonad, the present study investigated the expression of three AQPs (1, 2, and 9) in the testis of the neotropical anuran species Leptodactylus podicipinus during two different periods of the reproductive cycle (reproductive and non-reproductive). AQP1 and 2 immunoreactions were found in early germ cells, spermatozoa, Leydig cells, and Sertoli cells, which were more frequently expressed within the reproductive period. AQP1 was also found in the testicular blood vessels. AQP9 was identified predominantly in the epithelium of the intratesticular ducts of reproductive-period individuals. This study presents, for the first time, the localization of AQP1, AQP2, and AQP9 in the testes of an anuran species and the differences in their location during two distinct periods of the reproductive cycle.
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Fischer, Bernd, Pascale Chavatte-Palmer, Christoph Viebahn, Anne Navarrete Santos, and Veronique Duranthon. "Rabbit as a reproductive model for human health." REPRODUCTION 144, no. 1 (2012): 1–10. http://dx.doi.org/10.1530/rep-12-0091.
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The renaissance of the laboratory rabbit as a reproductive model for human health is closely related to the growing evidence of periconceptional metabolic programming and its determining effects on offspring and adult health. Advantages of rabbit reproduction are the exact timing of fertilization and pregnancy stages, high cell numbers and yield in blastocysts, relatively late implantation at a time when gastrulation is already proceeding, detailed morphologic and molecular knowledge on gastrulation stages, and a hemochorial placenta structured similarly to the human placenta. To understand, for example, the mechanisms of periconceptional programming and its effects on metabolic health in adulthood, these advantages help to elucidate even subtle changes in metabolism and development during the pre- and peri-implantation period and during gastrulation in individual embryos. Gastrulation represents a central turning point in ontogenesis in which a limited number of cells program the development of the three germ layers and, hence, the embryo proper. Newly developed transgenic and molecular tools offer promising chances for further scientific progress to be attained with this reproductive model species.
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Khawar, Muhammad, Abdullah Sohail, and Wei Li. "SIRT1: A Key Player in Male Reproduction." Life 12, no. 2 (2022): 318. http://dx.doi.org/10.3390/life12020318.
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Reproduction is the way to immortality for an individual, and it is essential to the continuation of the species. Sirtuins are involved in cellular homeostasis, energy metabolism, apoptosis, age-related problems, and sexual reproduction. Sirtuin 1 (SIRT1) belongs to the sirtuin family of deacetylases, and it is a nicotinamide adenine dinucleotide (NAD)-dependent deacetylase. It removes the acetyl group from a variety of substrates. SIRT1 regulates endocrine/metabolic, reproductive, and placental development by deacetylating histone, different transcription factors, and signal transduction molecules in a variety of cellular processes. It also plays a very important role in the synthesis and secretion of sex hormones via regulating the hypothalamus-pituitary-gonadal (HPG) axis. Moreover, SIRT1 participates in several key stages of spermatogenesis and sperm maturation. The current review will give a thorough overview of SIRT1’s functions in male reproductive processes, thus paving the way for more research on restorative techniques and their uses in reproductive medicine.
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Castelo-Branco, Camil, and Iris Soveral. "Phytoestrogens and bone health at different reproductive stages." Gynecological Endocrinology 29, no. 8 (2013): 735–43. http://dx.doi.org/10.3109/09513590.2013.801441.
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Soules, M. R., S. Sherman, E. Parrott, et al. "Executive summary: Stages of Reproductive Aging Workshop (STRAW)." Climacteric 4, no. 4 (2001): 267–72. http://dx.doi.org/10.1080/cmt.4.4.267.272.
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Soules, M. R., S. Sherman, E. Parrott, et al. "Executive summary: Stages of Reproductive Aging Workshop (STRAW)." Climacteric 4, no. 4 (2001): 267–72. http://dx.doi.org/10.1080/713605136.
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Soules, Michael R., Sherry Sherman, Estella Parrott, et al. "Executive summary: stages of reproductive aging workshop (STRAW)." Fertility and Sterility 76, no. 5 (2001): 874–78. http://dx.doi.org/10.1016/s0015-0282(01)02909-0.
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Hennig, Lars, Wilhelm Gruissem, Ueli Grossniklaus, and Claudia Köhler. "Transcriptional Programs of Early Reproductive Stages in Arabidopsis." Plant Physiology 135, no. 3 (2004): 1765–75. http://dx.doi.org/10.1104/pp.104.043182.
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Siebers, Matthew H., Rebecca A. Slattery, Craig R. Yendrek, et al. "Simulated heat waves during maize reproductive stages alter reproductive growth but have no lasting effect when applied during vegetative stages." Agriculture, Ecosystems & Environment 240 (March 2017): 162–70. http://dx.doi.org/10.1016/j.agee.2016.11.008.
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