Reproductive Cycle Research Articles

Evaluation of naturally acquired immune responses against novel pre-erythrocytic Plasmodium vivax proteins in a low endemic malaria population located in the Peruvian Amazon Basin

BackgroundPlasmodium vivax represents the most geographically widespread human malaria parasite affecting civilian and military populations in endemic areas. Targeting the pre-erythrocytic (PE) stage of the parasite life cycle is especially appealing for developing P. vivax vaccines as it would prevent disease and transmission. Here, naturally acquired immunity to a panel of P. vivax PE antigens was explored, which may facilitate vaccine development and lead to a better understanding of naturally acquired PE immunity.MethodsTwelve P. vivax PE antigens orthologous to a panel of P. falciparum antigens previously identified as highly immunogenic in protected subjects after immunization with radiation attenuated sporozoites (RAS) were used for evaluation of humoral and cellular immunity by ELISA and IFN-γ ELISpot. Samples from P. vivax infected individuals (n = 76) from a low endemic malaria region in the Peruvian Amazon Basin were used.ResultsIn those clinical samples, all PE antigens evaluated showed positive IgG antibody reactivity with a variable prevalence of 58–99% in recently P. vivax diagnosed patients. The magnitude of the IgG antibody response against PE antigens was lower compared with blood stage antigens MSP1 and DBP-II, although antibody levels persisted better for PE antigens (average decrease of 6% for PE antigens and 43% for MSP1, p < 0.05). Higher IgG antibodies was associated with one or more previous malaria episodes only for blood stage antigens (p < 0.001). High IgG responders across PE and blood stage antigens showed significantly lower parasitaemia compared to low IgG responders (median 1,921 vs 4,663 par/µl, p < 0.05). In a subgroup of volunteers (n = 17),positive IFN-γ T cell response by ELISPOT was observed in 35% vs 9–35% against blood stage MSP1 and PE antigens, respectively, but no correlation with IgG responses.ConclusionsThese results demonstrate clear humoral and T cell responses against P. vivax PE antigens in individuals naturally infected with P. vivax. These data identify novel attractive PE antigens suitable for use in the potential development and selection of new malaria vaccine candidates which can be used as a part of malaria prevention strategies in civilian and military populations living in P. vivax endemic areas.

Applications of zinc stable isotope analysis in environmental and biological systems: a review

Zinc (Zn) is an essential trace element that is involved in both biotic and abiotic processes in Earth's surface environments. Over the last 20 years, advances in mass spectrometry instrumentation have enabled unprecedented high-precision Zn isotope abundance ratio determinations in natural and anthropogenic samples. Supported by a solid theoretical background inherited from the traditional non-metal stable isotopes (C, N, H, O, S), the understanding of the controlling factors of Zn isotope fractionation has rapidly evolved. In this article, we review the main applications and findings of Zn isotopes in a variety of scientific domains, including metal contamination, magmatic differentiation, plant uptake, weathering, global climate change, dietary and trophic chains, and biomedicine. The analytical aspects of Zn isotope determination in solid and water samples and the principles and mechanisms of Zn isotope fractionation are also reviewed. This work aims to provide a general yet in-depth panorama of Zn isotope chemistry and demonstrate the versatility and potential of this isotope system for studying the biological, geological, and chemical cycling of Zn. Supplementary material: https://doi.org/10.6084/m9.figshare.c.7240146

Exogenous xylanase increases total tract digestibility of energy and fiber in diets for gestating and lactating sows, but does not influence reproductive performance of sows

The hypothesis that exogenous xylanase added to diets for gestating and lactating sows will increase the apparent total tract digestibility (ATTD) of gross energy (GE) and total dietary fiber (TDF), increase digestible energy (DE) and metabolizable energy, and improve the reproductive performance of sows was tested. Two diets for gestating sows and two diets for lactating sows were formulated without or with 100 g per ton of an exogenous xylanase (16,000 units/kg). Diets were fed in two consecutive reproductive cycles. From 106 animals, 48 pregnant sows, organized in 4 blocks of 12 sows (6 sows per treatment in each block), were placed for 10 days in metabolism crates starting on day 35 (mid-gestation) and again on day 95 (late-gestation) with feces and urine being collected for 4 days. Sows were moved to the lactation unit on day 106 of gestation and feeding of lactation diets was initiated. Fecal samples were collected (grab-sampling) from days 10–14 post-farrowing. The number and weight of pigs born, mummified, stillborn, and weaned per sow were recorded, and survival rate and litter average daily gain were calculated. Litters were weaned on day 20 ± 1. All animals were rebred and 46 sows were placed in metabolism crates in mid and late-gestation as in the first cycle, and treatments in the farrowing unit during the second cycle were also as in the first cycle; however, colostrum and milk samples were collected from sows in the second cycle. Results indicated that reproductive performance was not different between sows fed control diets and sows fed diets with xylanase during the two reproductive cycles. In the first gestation period, the ATTD of TDF in late-gestation was greater (P < 0.05) in sows fed the diet with xylanase than in sows fed the control diet. During the first lactation, sows fed the diet with xylanase had greater (P < 0.05) ATTD of GE and TDF, and greater (P < 0.05) DE than sows fed the control diet. During the second gestation, sows fed the diet with xylanase had greater (P < 0.05) DE in mid-gestation. During the second lactation, sows fed the diet with xylanase had greater (P < 0.05) ATTD of GE and TDF, and greater (P < 0.05) DE than sows fed the control diet. In conclusion, DE was greater in diets with xylanase than in control diets during the two reproductive cycles, and sows fed the lactation diet with xylanase had greater digestibility of fiber than sows fed the control diet.

A screen for Plasmodium falciparum sporozoite surface protein binding to human hepatocyte surface receptors identifies novel host–pathogen interactions

BackgroundSporozoite invasion of hepatocytes is an essential step in the Plasmodium life-cycle and has similarities, at the cellular level, to merozoite invasion of erythrocytes. In the case of the Plasmodium blood-stage, efforts to identify host–pathogen protein–protein interactions have yielded important insights including vaccine candidates. In the case of sporozoite-hepatocyte invasion, the host–pathogen protein–protein interactions involved are poorly understood.MethodsTo gain a better understanding of the protein–protein interaction between the sporozoite ligands and host receptors, a systematic screen was performed. The previous Plasmodium falciparum and human surface protein ectodomain libraries were substantially extended, resulting in the creation of new libraries comprising 88 P. falciparum sporozoite protein coding sequences and 182 sequences encoding human hepatocyte surface proteins. Having expressed recombinant proteins from these sequences, a plate-based assay was used, capable of detecting low affinity interactions between recombinant proteins, modified for enhanced throughput, to screen the proteins for interactions. The novel interactions identified in the screen were characterized biochemically, and their essential role in parasite invasion was further elucidated using antibodies and genetically manipulated Plasmodium parasites.ResultsA total of 7540 sporozoite-hepatocyte protein pairs were tested under conditions capable of detecting interactions of at least 1.2 µM KD. An interaction between the human fibroblast growth factor receptor 4 (FGFR4) and the P. falciparum protein Pf34 is identified and reported here, characterizing its affinity and demonstrating the blockade of the interaction by reagents, including a monoclonal antibody. Furthermore, further interactions between Pf34 and a second P. falciparum rhoptry neck protein, PfRON6, and between human low-density lipoprotein receptor (LDLR) and the P. falciparum protein PIESP15 are identified.Conditional genetic deletion confirmed the essentiality of PfRON6 in the blood-stage, consistent with the important role of this protein in parasite lifecycle. Pf34 was refractory to attempted genetic modification. Antibodies to Pf34 abrogated the interaction and had a modest effect upon sporozoite invasion into primary human hepatocytes.ConclusionPf34 and PfRON6 may be members of a functionally important invasion complex which could be a target for future interventions. The modified interaction screening assay, protein expression libraries and P. falciparum mutant parasites reported here may be a useful tool for protein interaction discovery and antigen candidate screening which could be of wider value to the scientific community.

Predilection Site for the Meat Lover Trichinella spp Larvae and its Pathogenesis and Potency in Human Host

Aims: To revisited carefully previously published articles available in the internet regarding predilection site of Trichinella spp larvae including their pathogenesis and its potency. Discussion: By carefully reviewing previously published literature available in the internet regarding the parasite Trichinella tropism to its host’s striated muscle, the author briefly withdraw some important keypoint to be revealed. The nematode Trichinella spp causes serious zoonosis called trichinellosis, a disease affecting striated or skeletal muscles which consider as one of tropical disease. Even though its natural host varied, but infection among live stocks, such as pigs and other animals, which are raising public health concern. Human infection occurs after consumption of raw or undercooked meat or meat products contain muscle larvae of T. spiralis. The tropism of the parasite for individual striated muscles and/or striated muscle groups varies significantly. Trichinella spp. has a direct life cycle where all three life cycle stages (the infective muscle larvae, adult, and new born larvae) happen serially in one host only. Intestine-dwelling adults of Trichinella produce newborn larvae that bypass the enterocyte, enter the bloodstream and colonize skeletal muscle. The muscle larvae assemble excretory-secretory products which play crucial role in establishing and maintaining persistent parasitism and the host’s immune modulation and evasion. It turns out that excretory-secretory products from muscle larvae and mature worm also have hidden medical potential that can be used to treat allergic problems, inflammation-based diseases, autoimmunity and even malignancy. Conclusion: Trichinellosis is a serious and potentially fatal zoonosis which transmitted through consuming raw or uncooked contaminated meat or its comestibles. Its primary tropism is to the host’s striated muscle and infection can persist for a long time facilitated by several reciprocities of its product (e.g., excretory-secretory) with the host’s cell and immune system. Fortunately, there are several promising potency in the field of therapeutic and prevention medicine which should be explored intensely.

CONIFEROUS LEAF-BEARING FOREST BIOMASS ASSESSMENT BY THE EXAMPLE OF THE EDUCATIONAL AND EXPERIMENTAL SOIL AND ECOLOGICAL CENTER OF LOMONOSOV MOSCOW STATE UNIVERSITY “CHASHNIKOVO”

The aim of the work was to assess the contribution of the following components - biomass and mortmass of tree stands, undergrowth, living ground cover, and forest litter - to the total organic matter’s pool of plant community. The object of the study was a territory of coniferous-deciduous forest located in Solnechnogorsk City District of the Moscow region, in which five permanent sample trial plots of 50·50 m were allocated. The greatest contribution to the total organic matter mass of studied plant communities was made by forest stand perennial parts (up to 87%) and forest stand mortmass (up to 14%), and phytomass of deciduous trees in stand containing 32 to 98%, which was connected with incompleteness of forest restoration succession process. The contribution of forest litter was no more than 3%; litter deposit was low (0,18-1,21 kg·m-2), which is not typical for spruce forests, as is the fact that all litter is of the destructive type. Living ground cover in terms of floristic composition and ecological-coenotic structure was typical for the subzone of coniferous-deciduous forests; its contribution to the overall productivity of forest biogeocenosis was insignificant. The spatial intrabiogeocenotic structure of litter reserves and living ground cover biomass distribution was disturbed compared to typical spruce forests due to the high proportion of deciduous species in the forest stand. Deciduous species inclusion in the tree tier, typical of the final stage of formation of a secondary coniferous forest during succession, caused a slight increase in the intensity of the biological cycle, which was indicated in this case by a decrease in the supply of litter and a simplification of their structure. Since the biomass and mortmass of tree stand make the greatest contribution to the sequestration of carbon by forest biogeocenoses, it is these components that require the most detailed assessment during monitoring observations, the purpose of which is to assess the carbon reserves of terrestrial ecosystems.

Особенности гормональной регуляции индуцированного полового цикла овцематок

The purpose of the study is to identify patterns of changes in the content of progesterone, FSH, LH and free estriol under various options for inducing the reproductive cycle of ewes with hormonal drugs. Objectives: during the period of spring anaphrodisia, to stimulate sexual oestrus in ewes using a double injection of estrofan; during the same period, to stimulate sexual estrus in ewes according to the follimag-progestamag, surfagon scheme; to study the nature of changes in the content of sex hormones in the blood serum of ewes during the implementation of the specified schemes for stimulating sexual heat; to identify the pattern of dynamics of sex hormones in ewes during an induced sexual cycle. The study was conducted in the Orenburg Region in April 2022 on Romanov breed ewes. Three groups of ewes of 12 heads each were formed. The age of the sheep is 3–5 years, live weight is 30–35 kg. The experiment was carried out against the background of fortification of sheep with E-selenium. In groups I (control) and II, animals were administered E-selenium on the 1st and 11th days of the experiment, in group III – on the 1st and 8th days. Hormonal stimulants were not used in the control; in group II, sheep were administered estrofan on days 1 and 11 and surfagon on the 13th day of the experiment; in group III, follimag was used on the 1st day, progestamag and surfagon on the 8th day. To determine the hormone content, blood was taken from the jugular vein from all animals on the 1st, 8th, 11th, 13th, and 14th days of the experiment. When stimulating sexual heat in ewes during seasonal anaphrodisia, the most pronounced hormonal response was obtained using injections of follimag and progestamag with surfagon at weekly intervals. When using this regimen, the levels of free estriol and LH reached their maximum values by the 11th day from the start of stimulation, creating optimal conditions for ovulation. After stimulating sexual heat in ewes, it is advisable to begin mating or insemination on the 10th–11th day.

The myxozoans Myxobolus cerebralis and Tetracapsuloides bryosalmonae modulate rainbow trout immune responses: quantitative shotgun proteomics at the portals of entry after single and co-infections.

Little is known about the proteomic changes at the portals of entry in rainbow trout after infection with the myxozoan parasites, Myxobolus cerebralis, and Tetracapsuloides bryosalmonae. Whirling disease (WD) is a severe disease of salmonids, caused by the myxosporean M. cerebralis, while, proliferative kidney disease (PKD) is caused by T. bryosalmonae, which instead belongs to the class Malacosporea. Climate change is providing more suitable conditions for myxozoan parasites lifecycle, posing a high risk to salmonid aquaculture and contributing to the decline of wild trout populations in North America and Europe. Therefore, the aim of this study was to provide the first proteomic profiles of the host in the search for evasion strategies during single and coinfection with M. cerebralis and T. bryosalmonae. One group of fish was initially infected with M. cerebralis and another group with T. bryosalmonae. After 30 days, half of the fish in each group were co-infected with the other parasite. Using a quantitative proteomic approach, we investigated proteomic changes in the caudal fins and gills of rainbow trout before and after co-infection. In the caudal fins, 16 proteins were differentially regulated post exposure to M. cerebralis, whereas 27 proteins were differentially modulated in the gills of the infected rainbow trout post exposure to T. bryosalmonae. After co-infection, 4 proteins involved in parasite recognition and the regulation of host immune responses were differentially modulated between the groups in the caudal fin. In the gills, 11 proteins involved in parasite recognition and host immunity, including 4 myxozoan proteins predicted to be virulence factors, were differentially modulated. The results of this study increase our knowledge on rainbow trout co-infections by myxozoan parasites and rainbow trout immune responses against myxozoans at the portals of entry, supporting a better understanding of these host-parasite interactions.

Microscopic Analysis of Nuclear Speckles in a Viviparous Reptile.

Nuclear speckles are compartments enriched in splicing factors present in the nucleoplasm of eucaryote cells. Speckles have been studied in mammalian culture and tissue cells, as well as in some non-mammalian vertebrate cells and invertebrate oocytes. In mammals, their morphology is linked to the transcriptional and splicing activities of the cell through a recruitment mechanism. In rats, speckle morphology depends on the hormonal cycle. In the present work, we explore whether a similar situation is also present in non-mammalian cells during the reproductive cycle. We studied the speckled pattern in several tissues of a viviparous reptile, the lizard Sceloporus torquatus, during two different stages of reproduction. We used immunofluorescence staining against splicing factors in hepatocytes and oviduct epithelium cells and fluorescence and confocal microscopy, as well as ultrastructural immunolocalization and EDTA contrast in Transmission Electron Microscopy. The distribution of splicing factors in the nucleoplasm of oviductal cells and hepatocytes coincides with the nuclear-speckled pattern described in mammals. Ultrastructurally, those cell types display Interchromatin Granule Clusters and Perichromatin Fibers. In addition, the morphology of speckles varies in oviduct cells at the two stages of the reproductive cycle analyzed, paralleling the phenomenon observed in the rat. The results show that the morphology of speckles in reptile cells depends upon the reproductive stage as it occurs in mammals.

The real subsumption of nature and cryopolitics: Temporal fixes in dairy farming in Southern Italy

Water buffaloes have a seasonal cycle of reproduction. Normally they tend to reproduce more when the daylight hours decrease. This seasonal reproduction also means that most of the buffalo calves would be born in autumn and winter in Italy where buffaloes are dairy animals, and milk production would be the highest in these seasons. However, consumer demand for the PDO (Protected designation of origin) mozzarella cheese is the highest in spring and summer. In order to deal with the imbalances between the seasonality of milk production and mozzarella consumption, and the strict regulations of the PDO cheese production, farmers and veterinarians resort to a temporal fix, and they regularly deseasonalise buffalo reproduction. However, there is an obvious discrepancy between the use of this and other fixes (cryotechnologies) generally associated with industrial agriculture, and the idea of traditional and sustainable food production. By engaging with relevant economic geography and political ecology literature, this paper investigates the temporal fixes in dairy farming and agri-food production through an in-depth empirical analysis of deseasonalisation, as a particular form of the real subsumption of nature, and cryopolitics in buffalo mozzarella cheese production in Southern Italy. The work presented in this article is based on multi-sited qualitative field research of buffalo farming and mozzarella cheese production in Campania region. This paper also has wider implications on how socio-ecological fixes shape ‘just-in-time’ animal agriculture and agri-food production.

Reproductive traits of the deep-sea shrimp Plesionika williamsi (decapoda: Pandalidae) from the eastern-central atlantic

The reproductive aspects of all Plesionika species are relatively well known worldwide, except for the deepest species of the genus, Plesionika williamsi, for which little information is available throughout its range. The ovarian maturity, sex ratio, brood size, and size-depth distribution of the deep-sea shrimp Plesionika williamsi (Pandalidae) in the Canary Islands (eastern-central Atlantic) were analysed. Ovigerous females were observed all year round, with the highest number of ovigerous females recorded between July and October. The presence of a greater number of ovigerous females during the summer may reflect a high local availability of food or the optimal abiotic conditions, which are factors with a strong influence on reproduction. The presence of non-ovigerous mature females throughout the year indicates that their resting period in the reproductive cycle occurs asynchronously. The physiological size at first sexual maturity was 19.24 mm in carapace length (CL) and the length at first sexual maturity was estimated at 23.15 mm CL. Estimates of size at first sexual maturity based on ovigerous females describe the result of the reproduction process, whereas size at first sexual maturity based on ovarian maturity deals with physiological preparation for reproduction. The modal size class of egg production was 24–30 mm CL, which yielded 83.22% of the population egg production. Plesionika williamsi is an iteroparous species that can produce small eggs during egg extrusion. The mean number of external embryos carried by females was 3048 and can be considered a true approximation of the number of larvae released in each batch, which depend on the conditions existing in each system. The shallower individuals are associated with a depth stratum that represents the boundary between two water masses present in the Canary Islands. The increase in size with depth is related to the presence of submarine volcanic canyons, which constitutes a flow channel of surface organic matter to depth.

Embryology of the fat-tailed dunnart (Sminthopsis crassicaudata): A marsupial model for comparative mammalian developmental and evolutionary biology.

Marsupials are a diverse and unique group of mammals, but remain underutilized in developmental biology studies, hindering our understanding of mammalian diversity. This study focuses on establishing the fat-tailed dunnart (Sminthopsis crassicaudata) as an emerging laboratory model, providing reproductive monitoring methods and a detailed atlas of its embryonic development. We monitored the reproductive cycles of female dunnarts and established methods to confirm pregnancy and generate timed embryos. With this, we characterized dunnart embryo development from cleavage to birth, and provided detailed descriptions of its organogenesis and heterochronic growth patterns. Drawing stage-matched comparisons with other species, we highlight the dunnarts accelerated craniofacial and limb development, characteristic of marsupials. The fat-tailed dunnart is an exceptional marsupial model for developmental studies, where our detailed practices for reproductive monitoring and embryo collection enhance its accessibility in other laboratories. The accelerated developmental patterns observed in the Dunnart provide a valuable system for investigating molecular mechanisms underlying heterochrony. This study not only contributes to our understanding of marsupial development but also equips the scientific community with new resources for addressing biodiversity challenges and developing effective conservation strategies in marsupials.

Effects of Exposure to Electromagnetic Fields (EMFs) on Biological Systems

Electromagnetic Field (EMF) is a natural phenomenon; however, anthropogenic activities have significantly shifted its equilibrium, leading to potential deleterious effects on biological systems. As technology becomes more integrated into daily life, the increased use of electronic devices has contributed to a rise in man-made EMF exposure. This exposure can affect biological systems on physiological and molecular levels, raising concerns about its potential effects on animal development, reproductive systems, and overall ecosystem health. The review explores the physiological effects of exposure to static, extremely low-frequency (ELF), and radiofrequency (RF) fields, analyzing how EMF impacts oxidative stress, reproductive physiology, cardiovascular function, brain and nervous system activity, and DNA/RNA integrity. It also acknowledges the emerging concern of EMF in aquatic environments, where underwater power supplies and extensive underwater cable networks are sources of EMF exposure that may affect marine and freshwater species. The potential effects on marine life include disruptions to migratory patterns, altered reproductive cycles, and changes in aquatic biodiversity. The review acknowledges that research on EMF has improved over time, but significant gaps and information remain. It emphasizes the need for immediate attention to address the challenges and opportunities in this field.

Gendered Harm and Social Abandonment: Stories of the Dooars Women Tea Garden Workers

The Tea Tribes of the Dooars in West Bengal are of the numerically preponderant culturally and socially dispossessed Adivasi population of Chota Nagpur and make up 80% of the tea plantation labour force. These tribes especially its women who form around 60% of the labour pool in the Dooars, serve as crucial social capital for the sustenance and burgeoning of the plantation industry. The tribes exhibit localised and hybridised social customs that have historically been in a dialectic relationship with the culture of commerce that predominates a capitalist bureaucratic organisation. This acculturation and an unfortunate reign of neglect have given birth to distinctive social arrangements, with the article examining the curious social currents of lone motherhood and abandonment of women shaping the household and thereby the social reproduction cycle of the tea industry. By invoking a feminist methodology, qualitative in-depth interpretive interviews of lone mothers and deserted women have been conducted to understand their renditions of gendered neglect and subliminal violence, while attempting to discover their position in the communitas of the tea industry. The study was conducted in the district of Jalpaiguri, with a heavy concentration of the Scheduled Tribe (62%) of the Adivasi subgroup found in its 89 registered tea gardens. The ‘thick’ descriptions of women’s narratives reveal nuanced notions of gender and intimate partner abuse, that shine light on violence characterised by its distinctive low intensity and its latent and subliminal nature evinced in the breach of a social compact. The nature of mistreatment and abuse that they describe opens up conceptual chinks in existing feminist literature on violence while providing further avenues to deliberate upon them. Imperfect, yet partial access to education, social media and government outreach as tools of modernity are however stoking aspirations for social justice, ineffectively handled by poorly trained and gender unresponsive socio-legal and bureaucratic agents.

On-target, dual aminopeptidase inhibition provides cross-species antimalarial activity.

To combat the global burden of malaria, development of new drugs to replace or complement current therapies is urgently required. Here, we show that the compound MMV1557817 is a selective, nanomolar inhibitor of both Plasmodium falciparum and Plasmodium vivax aminopeptidases M1 and M17, leading to inhibition of end-stage hemoglobin digestion in asexual parasites. MMV1557817 can kill sexual-stage P. falciparum, is active against murine malaria, and does not show any shift in activity against a panel of parasites resistant to other antimalarials. MMV1557817-resistant P. falciparum exhibited a slow growth rate that was quickly outcompeted by wild-type parasites and were sensitized to the current clinical drug, artemisinin. Overall, these results confirm MMV1557817 as a lead compound for further drug development and highlights the potential of dual inhibition of M1 and M17 as an effective multi-species drug-targeting strategy.IMPORTANCEEach year, malaria infects approximately 240 million people and causes over 600,000 deaths, mostly in children under 5 years of age. For the past decade, artemisinin-based combination therapies have been recommended by the World Health Organization as the standard malaria treatment worldwide. Their widespread use has led to the development of artemisinin resistance in the form of delayed parasite clearance, alongside the rise of partner drug resistance. There is an urgent need to develop and deploy new antimalarial agents with novel targets and mechanisms of action. Here, we report a new and potent antimalarial compound, known as MMV1557817, and show that it targets multiple stages of the malaria parasite lifecycle, is active in a preliminary mouse malaria model, and has a novel mechanism of action. Excitingly, resistance to MMV15578117 appears to be self-limiting, suggesting that development of the compound may provide a new class of antimalarial.

Screening methods for thermotolerance in pollen.

Plant reproduction is highly susceptible to temperature stress. The development of the male gametophyte in particular represents a critical element in the reproductive cycle with high sensitivity to elevated temperatures. Various methods have been used to test the effect of temperature stress on pollen performance or to determine the degree of susceptibility of given species and genotypes. The information gained informs the development of new crop varieties suited to grow under warmer conditions arising through climate change and facilitates predicting the behavior of natural populations under these conditions. The characterization of pollen performance typically employs the terms pollen viability and pollen vigor, which, however, are not necessarily used consistently across studies. Pollen viability is a nominal parameter and is often assayed relying on cellular features as proxy to infer the capability of pollen grains to germinate and complete double fertilization. Alternatively, pollen germination can be determined through in vitro growth assays, or by monitoring the ability of pollen tubes to complete different progamic steps in vivo (ability to reach an ovule, release sperm cells, lead to seed set). Pollen vigor is an ordinal parameter that describes pollen tube growth rate or the efficiency of pollen tube growth as inferred by its morphology or growth pattern. To ensure consistent and relevant terminology, this review defines these terms and summarizes the methodologies used to assess them.

Problems Encountered in Marketing Sustainable Products and Suggested Solutions in Turkey

The growth of the consumer economy in the last century has led to several significant issues that endanger human life. Overexploitation of nature and soils, the use of pesticides and growth stimulants have had a negative impact on the environment and water resources. The current situation has necessitated that societies worldwide adopt new production approaches to immediately halt soil degradation and improve water quality. One production approach that aims to protect public health and the environment is sustainable production. Sustainable production is an ecological management system that promotes biodiversity, biological cycles, and soil biological activity. The farming system is based on minimal use of off-farm inputs and management practices that restore, maintain or enhance ecological harmony. The aim of this study is to explain the importance of sustainable products and production, to address the problems and suggestions encountered in the marketing of sustainable products in Turkey, and to propose solutions.

High capacities of carbon capture and photosynthesis of a novel organic carbon-fixing microalgae in municipal wastewater: From mutagenesis, screening, ability evaluation to mechanism analysis

The development of wastewater treatment processes capable of reducing and fixing carbon is currently a hot topic in the wastewater treatment field. Microalgae possess a natural carbon-fixing advantage, and microalgae that can symbiotically coexist with indigenous bacteria in actual wastewater attract more significant attention. Ultraviolet (UV) mutagenesis and dissolved organic carbon (DOC) acclimation were applied to strengthen the carbon-fixing performance of microalgae in this study. The mechanisms associated with microalgal water purification ability, gene regulation at the molecular level and photosynthetic potential under different trophic modes resulting from carbon fixation and transformation were disclosed. The superior performance of Chlorella sp. MHQ2 was eventually screened out among a large number of mutants generated from 3 wild-type Chlorella strains. Results indicated that the dry cell weight of the optimal species Chlorella sp. HQ mutant MHQ2 was 1.91 times that of the wild strain in the pure algal system, more carbon from municipal wastewater (MW) were transferred to the microalgae and re-entered into the biological cycle through resource utilization. In addition, COD, NH3-N and TP removal efficiencies of MW by Chlorella sp. MHQ2 were found to increase to 95.8% (1.1-times), 96.4% (1.4-times), and 92.9% (1.2-times), respectively, under the extra DOC supply and the assistance of indigenous bacteria in the MW. In the transcriptome analysis of the logarithmic phase, the glycolytic pathway was inhibited, and the pentose phosphate pathway was mainly carried out for microalgal life activities, further promoting efficient energy utilization. Upon analysis of carbon capture capacity and photosynthetic potential in trophic mode, the addition of NaHCO3 increased the photosynthetic rate of Chlorella sp. MHQ2 in mixotrophy whereas it was attenuated in autotrophy. This study could provide a new perspective for the study of resource utilization and microalgae carbon- fixing mechanisms in the actual wastewater treatment process.

13 Impact of precision feeding during gestation on the productive career of sows over three reproductive parities

Abstract The aim of this study was to evaluate the impact of precision feeding during gestation on the career performances and longevity of sows, initially gilts, monitored over three successive reproductive cycles. Four isoenergetic treatments were compared: two conventional constant-concentration feeding strategies (0.53 % DIS Lys) with feed supply either constant (flat feeding; FF) or variable (bump feeding; BF), and two precision feeding strategies based on the InraPorc model applied considering either the mean weight by parity (PFP) or the individual weight of each sow at breeding (PFI). Four groups, representing 393 gilts, were followed from breeding to weaning over three cycles. Body weight and backfat depth were measured at breeding, 90 d of gestation, parturition, and weaning. Feed consumption was monitored daily. Litter variables were measured, including birth and weaning weight, mortality, and overall body weight gain. A mixed model was used to analyze differences between the four treatments using the sow as the experimental unit for performance analysis during the third reproductive cycles. For the analysis of the overall productive career over the three reproductive cycles, the performances of the two conventional strategies (with constant Lys DIS concentration feeding, CONV) were compared with the two precision feeding strategies (PF). During the third cycle, PFP and PFI sows had a lighter body weight at the beginning of gestation than the FF sows (P &amp;lt; 0.01), but increased their body weight gain during gestation (P &amp;lt; 0.001). Backfat loss in PFP and PFI sows during lactation was greater compared with BF sows (P = 0.05), FF sow being intermediate. PFP sows had a lower stillborn rate (P = 0.04) and tended to have less total piglet mortality (P = 0.06) than FF and BF sows. Over the three reproductive cycles, the stillborn rate and total piglet mortality were less in PF sows than in CONV sows (respectively -0.9 %; P = 0.02 and -1.5 %; P = 0.03). PF sows weaned more piglets during their three cycles than CONV sows did (+ 0.7; P = 0.03), with weaning litter weight gain also increasing for PF sows (+3.7 %; P = 0.02). The culling rate of gilts after three cycles did not differ significantly among treatments (P = 0.27), but tended to be greater for PF sows after one cycle (+4.9 %; P = 0.08). The results seem to show a lasting benefit of precision feeding for sows, with a decrease in piglet mortality during lactation, suggesting greater piglet viability without significantly decreasing sow longevity.

275 Assessment of changes in hemoglobin concentration (Hb) in sows and their offspring over two consecutive reproductive cycles

Abstract There remains a knowledge gap regarding changes in hematological parameters, such as Hb, throughout the reproductive cycle of a sow. The principle aim of this study was to assess Hb concentartions in sows and their offspring over at least two consecutive reproductive cycles. Blood Hb measurements were initiated during the gilt stage and continued through parities 1 and 2, with measurements taken at six time points (d 30, 60, 90, and 112 of gestation; d 2 and 17 of lactation) involving a total of 13 sows. Sow body weight (BW) during gestation was 193.2 ± 38.1 kg for parity 1 and 220.7 ± 26.2 kg for parity 2; in lactation, sow BW was 201.5 ± 14.3 kg for parity 1 and 214.0 ± 19.6 kg for parity 2. Sow daily iron (Fe) intake, based on analyzed Fe content, was 0.621 ± 0.06 g during gestation and 1.79 ± 0.15 g during lactation across parities 1 and 2, which represents more than a 2-fold greater Fe intake than NRC 2012 requirement estimates. All liveborn piglets (n = 204 for parity 1; n = 201 for parity 2) underwent Hb measurements. Blood Hb concentrations were assessed within 24 h of birth before iron supplementation (200 mg iron dextran) and again at 17 d of age. Sows and piglets were classified as either anemic (Hb &amp;lt; 10 g/dL) or non-anemic (Hb ≥ 10 g/dL). Analysis of variance included the main effect of day, parity and their interaction based on Tukey’s comparison. In gestation Hb was less (P = 0.03) at d 90 in parity 1 and at d 90 and 112 in parity 2 (Table 1). Across parity, Hb was less (P = 0.02) at d 60 in parity 2. In lactation, Hb was least (P = 0.0002) at d 17 in parity 1 where sows were deemed anemic; in parity 2, sows were deemed anemic throughout lactation. The total number of piglets born and born alive was 17.15 ± 2.03 and 16.0 ± 1.9, respectively, for parity 1, and 17.0 ± 3.11 and 15.85 ± 2.41, respectively, for parity 2. Regardless of parity, piglet Hb was greater (P &amp;lt; 0.02) at weaning compared with birth. However, Hb concentrations were greater (P &amp;lt; 0.0001) at both time points in parity 2 piglets. There was a reduced incidence of anemia at birth (39.1% vs. 59.02%, respectively) and weaning (14.2% vs 36.1%, respectively) among piglets born in parity 2 compared with parity 1. The decline in sow Hb status with parity, particularly in lactation, suggests the need to explore strategies to improve Hb in sows with advancing parity. Alternatively, piglet Hb status improved with parity, indicating a need to modify iron supplementation methods to facilitate greater Hb in parity 1 litters.