Embryo Growth Rate Research Articles

Development and characterization of a novel intergeneric hybrid grouper (Cromileptes altivelis ♀ × Epinephelus lanceolatus ♂)

Distant hybridization often gives rise to offspring with hybrid vigor in plants and animals, and this method has also shown great potential in aquaculture. Grouper, an economically important marine species, has witnessed rapid growth in its related industry. To cultivate a new grouper variety with accelerated growth, superior meat quality, and high economic value, we successfully obtained fertilized eggs through artificial insemination, using humpback grouper (Cromileptes altivelis) as the maternal parent and giant grouper (Epinephelus lanceolatus) as the paternal parent. The hybrid groupers were successfully hatched and reared for up to 14 months. This study conducted comprehensive comparative analyses between the hybrid offspring and the parental species, focusing on embryo development, growth rate, morphological characteristics, chromosome karyotype and muscle nutrient composition. The hybrid grouper embryos completed their entire development, from fertilization to hatching, in an average duration of 20 h and 37 min, under controlled conditions of 28.5 ± 0.5 °C temperature and 28 part per thousand (ppt) salinity. Remarkably, the hybrid groupers exhibited significantly faster growth than humpback groupers, with an absolute weight growth rate 1.6 times higher. Additionally, the hybrid groupers displayed a 4.7% increase in meat yield compared to giant groupers. In terms of morphology, cluster analysis and principal component analysis were used to analyze the morphological framework data of the three grouper species, revealing that the hybrid groupers were more similar to giant groupers in their morphological framework. Chromosome karyotype and simple sequence repeats (SSR) analysis confirmed that the hybrid groupers have a total of 48 chromosomes, inheriting one set of chromosomes from each parent. This study provides a foundation for grouper hybrid breeding, and the hybrid groupers obtained in this research have the potential to become excellent commercial varieties.

O-203 Comparing viable and non-viable IVF early pregnancy measurements: does knowledge of gestational age using date of ET potentially change miscarriage diagnosis guidelines in IVF patients

Abstract Study question In IVF pregnancies with known embryo transfer (ET) dates, can gestational age as well as ultrasound measurements be used to diagnose miscarriage? Summary answer Early pregnancy measurements vary at fixed gestational ages based on ET. However, there is a specific time cut-off where an empty gestational sac indicates miscarriage. What is known already Current guidelines state that when ultrasound findings show a pregnancy of unknown viability, a repeat scan must be performed either 7 or 14 days later (depending on the presence of an embryo or gestation sac size) to confirm viability, irrespective of the LMP based gestational age. This definition only considers ultrasound measurements, and even when the pregnancy dates thought to be certain and based on day of ET date, there are no exceptions to this guidance. Study design, size, duration This was a retrospective cohort study within a London tertiary unit, Wolfson Clinic, Hammersmith Hospital, Imperial College Healthcare NHS Trust over a 36-month time period. We collated data from both fresh and frozen cycle IVF pregnancies over four years: Jan 1st 2019 to December 31st 2021. Participants/materials, setting, methods In this unit, patients undergoing fresh or frozen IVF cycles, have an embryo transfer at Day3-6 of development. We included any patient with a confirmed intrauterine pregnancy at first scan (5-8 weeks gestation) for analysis of pregnancy outcomes. The data collected included date of embryo transfer (ET), embryo age at transfer, and early pregnancy measurements using ultrasound. The endpoint was viability at the 11-14 week dating scan. Main results and the role of chance 1161 IVF embryo transfers were included in the study, 677 (58.3%) frozen and 484 (41.7%) fresh cycles. 892 (76.8%) remained viable at 11-14 weeks and 269 (23.2%) were non-viable. Pregnancies resulting in viable pregnancies had a range of CRL (≤16mm) and empty mean gestation sac diameter (MSD) (≤11mm) measurements at each expected age by ET date (≤8 weeks gestation). At 49 days CRL varied from 1mm to 17mm, and at 42 days empty MSD measurements varied from 7 to 18mm. This shows that a range in embryo and gestation sac sizes will be seen in subsequently shown to be viable pregnancies despite the apparent exact gestation being known based on ET. This may relate to both differing embryo growth rates and timing of implantation. A Kolmogorov-Smirnov test was applied to compare the viable and miscarriage cohort CRL measurements in relation to expected age by ET. The result: 0.610, p-value=1.33 x10-15, demonstrated a significant difference in embryo size between viable and non-viable pregnancies with known ET dates. All pregnancies where the scan showed an empty gestational sac (n = 157) at 47 days gestation by ET date, had a 100% positive predictive value with a 100% specificity (CI:90.1-100.0) for miscarriage. Limitations, reasons for caution The sample was powered to 0.9, significance level 0.05. Analysis demonstrated 100% positive predictive value with 100% specificity (CI:90.1-100.0), to confirm miscarriage with an empty gestation sac ≥47days age by ET date. A larger cohort size from different centres is needed to reduce the confidence interval and confirm the findings. Wider implications of the findings There is significant variation in CRL and MSD size between viable pregnancies of the same gestational age by ET. However, we found >47 days gestation an empty gestation sac resulted in miscarriage. If confirmed in larger studies this may permit women to be given an earlier definitive diagnosis of miscarriage. Trial registration number Audit registration GRM_104 Imperial Healthcare NHS Trust

Effects of low temperature on growth and metabolism of larval green sturgeon (Acipenser medirostris) across early ontogeny.

Southern Distinct Population Segment (sDPS) green sturgeon spawn solely in one stretch of the Sacramento River in California. Management of this spawning habitat is complicated by cold water temperature requirements for the conservation of winter-run Chinook salmon. This study assessed whether low incubation and rearing temperatures resulted in carryover effects across embryo to early juvenile life stages on scaling relationships in growth and metabolism in northern DPS green sturgeon used as a proxy for sDPS green sturgeon. Fish were incubated and reared at 11°C and 15°C, with a subset experiencing a reciprocal temperature transfer post-hatch, to assess recovery from cold incubation or to simulate a cold-water dam release which would chillrearing larvae. Growth and metabolic rate of embryos and larvae were measured to 118days post hatch. Reciprocal temperature transfers revealed a greater effect of low temperature exposure during larval rearing rather than during egg incubation. While 11°C eggs hatched at a smaller length, log-transformed length-weight relationships showed that these differences in developmental trajectory dissipated as individuals achieved juvenile morphology. However, considerable size-at-age differences persisted between rearing temperatures, with 15°C fish requiring 60days post-hatch to achieve 1g in mass, whereas 11°C fish required 120days to achieve 1g, resulting in fish of the same age at the completion of the experiment with a ca. 37-fold difference in weight. Consequently, our study suggests that cold rearing temperatures have far more consequential downstream effects than cold embryo incubation temperatures. Growth delays from 11°C rearing temperatures would greatly increase the period of vulnerability to predation in larval green sturgeon. The scaling relationship between log-transformed whole-body metabolism and mass exhibited a steeper slope and thus an increased oxygen requirement with size in 11°C reared fish, potentially indicating an energetically unsustainable situation. Understanding how cold temperatures affect green sturgeon ontogeny is necessary to refine our larval recruitment estimations for this threatened species.

The developmental pattern related to fatty acid uptake and oxidation in the yolk sac membrane and jejunum during embryogenesis in Muscovy duck

This study aimed to investigate the developmental change of body growth and gene expression related to fatty acid uptake and oxidation in the yolk sac membrane (YSM) and jejunum during embryogenesis in Muscovy ducks. The weights of embryos and yolk sac (YS) (5 embryos per replicate, n = 6) were recorded on embryonic days (E)16, E19, E22, E25, E28, E31, and the day of hatch (DOH). The fat and fatty acid contents in YSM, jejunal histology, and gene expression related to fatty acid metabolism in YSM and jejunum were determined in each sampling time. Among the nonlinear models, the maximum growth is estimated at 2.83 (E22.5), 2.67 (E22.1), and 2.60 (E21.3) g/d using logistic, Gompertz, and Von Bertalanffy models, respectively. The weight of YS, and ether extract-free YS as well as the amounts of fat and fatty acids in YS decreased (P < 0.05) linearly, whereas the villus height, crypt depth, villus height/crypt depth, and musculature thickness in jejunum increased (P < 0.05) linearly during embryogenesis. The mRNA expression of CD36, SLC27A4, and FABP1 related to fatty acid uptake as well as the mRNA and protein expressions of PPARα and CPT1 related to fatty acid oxidation increased in a quadratic manner (P < 0.05) in both YS and jejunum, and the maximum values were achieved during E25 to E28. In conclusion, the maximum growth rate of Muscovy duck embryos was estimated at 2.60 to 2.83 g/d on E21.3 to E23.5, while the accumulations of lipid and fatty acid in YS were decreased in association with the increased absorptive area of morphological structures in jejunum. The gene and protein expression involved in fatty acid metabolism displayed a similar enhancement pattern between YSM and jejunum during E25 to E28, suggesting that fatty acid utilization could be strengthened to meet the energy demand for embryonic development.

Limiting temperatures of embryo growth and seed germination of Fraxinus excelsior L. (Oleaceae): a threshold model approach

Key messageWe have examined thermal control for embryo growth and seed germination in European ash. Using historical data (span of 36 years) of embryo index in matured seeds, we showed that maturation is not influenced by the annual average temperature. Secondary dormancy in ash’s seeds is easily induced, and the thermal window for both embryo growth and seed germination was between 10 and 20 °C.ContextSeed germination plays a crucial role in establishing plant communities. Ash seeds are characterized by deep morphophysiological dormancy, usually overcome by 32 weeks of stratification. Observed climate changes might disrupt ash’s thermal window for embryo growth and seed germination. Thus, proper examination of seed adaptability can be important for forest management.AimsWe investigated the effect of temperature on the embryo index (ratio between embryo and seed length) as well as embryo growth and germination of European ash (Fraxinus excelsior L.) seeds under different thermal conditions.MethodsWe used seeds collected at the same site in Poland between 1985 and 2021 to first analyze the influence of the growing season on the initial embryo index in mature seeds. Subsequently, we examined embryo growth and germination of seeds at constant temperatures of 3°, 10°, 15°, 20°, 25°, and 30 °C from seeds collected in 2021. Using the modeled rate of embryo growth and germination, we predicted the cardinal temperatures for those processes in ash seeds.ResultsThe embryo index of ash seeds varied; however, there was no relationship between the index and year of seed collection. The base temperature for embryo growth was 1.4 ± 1.1 °C, with a ceiling temperature of 29.9 ± 2.0 °C and an optimal temperature of 15.7 ± 0.3 °C. The base temperature for germination was at − 1.8 ± 0.3 °C. Due to the induction of secondary dormancy, the ceiling temperature of germination was impossible to establish.ConclusionsThe initial embryo index of mature ash seeds seems to be an individual trait and was not affected by local average annual temperatures. The most effective temperature ranges for embryo growth and germination were similar, however narrow (between 10 and 15 °C). Temperatures above 20 °C inducted secondary dormancy, hampering embryo growth as well as germination. Such a narrow thermal window for embryo growth can potentially act as a limiting factor for the natural regeneration of ash seeds.

Role of external factors for cultivation of pacific oyster &lt;i&gt;Crassostrea gigas&lt;/i&gt; at a hatchery in Primorye. 1. The influence of temperature on development, growth and survival of embryos and larvae

The influence of temperature on development, growth and survival of pacific oyster Crassostrea gigas embryos and larvae is investigated in controlled conditions at a hatchery located in Peter the Great Bay (Japan Sea) — the TINRO subdivision for mariculture on Popov Island in July-August, 2019. The oyster embryos and larvae obtained from natural producers in the process of artificial spawning were grown under temperature of 21–22 оC (close to natural conditions in the coastal waters of Primorye) and 24–25 оC. The higher temperature had a positive effect on development and growth rate of embryos and larvae. Under the temperature of 24–25 оC, the embryogenesis was completed earlier by 2 hours, the transition to the D-veliger stage — by 8 hours, the stage of veliconch was reached in 1 day earlier, the stage of pediveliger — in 4 days earlier than under the temperature of 21–22 оC. The daily size increments were larger under the higher temperature, with the most significant differences at the stages of veliger (6.4 vs 4.2 µm day–1) and veliconch (14.3 vs 10.9 µm day–1), with no difference at the stage of pediveliger. The greatest average daily increment was reached with exotrophic nutrition (at the veliconch stage) in both cases. The larval mortality was higher under the higher temperature in 1.3 times at the stages from fertilized egg to D-veliger and in 1.4 times at the stages from D-veliger to pediveliger because of intensification of metabolic processes and the water pollution in the tanks for growing, with the largest difference at the stages of veliger and veliconch, as well, as the longest ones. There is concluded that the temperature of 24–25 оC lays within the range of optimal conditions for embryonic and larval development of pacific oyster (within the biokinetic zone) and this temperature is recommended for cultivation of this species in Primorye hatcheries, with selection of optimal parameters for the rearing.

Estradiol treatment prior to progesterone favors embryo survival in anestrous recipient mares

Previous studies have shown a positive correlation between the length of estrus prior to ovulation and fertility in cyclic donors and embryo recipient mares. Furthermore, higher endometrial expression of Uterocalin (P19) was found in anestrous mares treated with a 5 day estradiol protocol, compared to recipient mares with a short or no estradiol priming. However, it is not known how this extended estradiol exposure influences embryo survival. The objective of this study was to determine the effect of different lengths of estradiol treatment on embryo survival, growth and proportion of mitotic cells. Three experimental groups of anestrous recipient mares were used: (1) mares treated with long-acting progesterone (LA P4) only (NE); (2) mares treated with a single administration of 2.5mg of estradiol benzoate (SE) 2 days before LA P4; and (3) mares treated with 8mg of estradiol split into increasing doses for 5 consecutive days (LE) ending 3 days before LA P4 treatment. Embryos were recovered from donor mares 8 days after ovulation, and embryo diameter and grade were recorded. Only grade I and II expanded blastocysts were used for this study; they were transferred into recipient mares using a modified Wilsher's technique 4 days after LA P4. Embryo recovery was performed 2 days after transfer by uterine lavage to examine embryo survival and growth rate inthe three experimental groups. After a positive recovery, embryos were evaluated for grade, size and fixed in 1% paraformaldehyde for subsequent staining with Hoechst 33342 for nuclear evaluation by confocal microscopy. The proportion of mitotic cells was assessed for 4 areas (10,000µm2) per embryo. The likelihood of recovering an embryo 2 days after transfer was 46.1% (6/13), 62.5% (5/8) and 85.7% (6/7) for recipient mares from the NE, SE and LE groups, respectively (p =.09). The embryos recovered from the three different groups of recipients 48h after transfer did not, however, show any differences in size, morphology or in the proportion of nuclei undergoing mitosis (p>0.05). In conclusion, the duration of estradiol treatment before progesterone administration tended to influence embryo survival in anestrous recipients within 2 days of transfer. However, the grade and growth rate of surviving embryos did not differ among groups. This may indicate that if the endometrial environment is not optimal to support embryo development following transfer, the embryo dies and disappears relatively quickly, i.e. within 48 h, whereas surviving embryos continue to develop normally.

Effect of blastocyst quality on human sex ratio at birth in a single blastocyst frozen thawed embryo transfer cycle

Research question To determine whether blastocyst quality affects the sex ratio at birth through a single blastocyst frozen - thawed embryo transfer (SBFET) cycle. Design In this retrospective analysis, we examined 3,041 singleton infants born following SBFET between 2017 and 2020 at a single institution. We compared the sex ratios of these infants with respect to the blastocyst quality, embryo growth rate, and morphology. Results The main outcomes of this study were that the sex ratio (M/F) at birth of SBFET was 1.24. Mothers >40 years old had a considerably lower sex ratio than mothers <40 years old (0.39 vs. 1.23–1.28, p < .05). Transplanting high-quality blastocysts significantly increased the proportion of boys born (1.29 vs. 0.88, p < .05). There were no significant differences in the sex ratio with respect to the inner cell mass (ICM) score and expansion degree. Additionally, a high trophoblastic cell (TE) score resulted in a significantly higher sex ratio than the TE score with C (1.62 vs. 1.15 vs. 0.85, p < .001). Multivariable logistic regression analysis was performed to determine which variables were significant factors affecting sex ratio, and the outcomes were consistent with previous findings. Conclusions Our study indicated that high-quality, especially good TE score, had a higher chance of resulting in a male infant than a female infant.

Impact of epidermal growth factor and/or β-mercaptoethanol supplementations on the in vitro produced buffaloes' embryos.

The present study investigated the effects of epidermal growth factors (EGF) and/or β-Mercaptoethanol (βME) supplementations to oocyte maturation, fertilization, and culture media on the buffalo in vitro embryo production. The ovaries were collected and transferred within 2 h to the laboratory. The cumulus oocytes complexes were aspirated from 3 to 8 mm diameter follicles. Firstly, EGF; 0, 10, 20, or 50 ng/mL or βME; 0, 25, 50, 100, or 200 μM were supplemented to the in vitro maturation (TCM-199), fertilization (IVF-TALP), or culture (IVC: SOF) media. Our results revealed that supplementing EGF (20 ng/mL) to the TCM-199, IVF-TALP, or SOF media could efficiently improve the growth rates and development of buffalos' embryos, while EGF (50 ng/mL) could stimulate the embryo production only after treatment of the IVF-TALP /or SOF media, but not the IVM medium. However, βME was less efficient than EGF; it stimulated the growth rates of buffalo embryos when supplemented with the maturation and fertilization (IVF-TALP) media in a 50 μM concentration. Secondly, combined EGF (20 ng/mL) and βME (50 μM) were supplemented to the maturation media as effective concentration. The combined treatment of EGF (20 ng/mL) and βME (50 μM) showed no significant enhancing effect on the buffalo embryos compared to each alone. For future perspectives, further study is required to examine the effects of combined EGF and βME on the maturation and fertilization of buffalo oocytes at different categories of age and seasonal localities.

Global diversity and adaptations of avian eggshell thickness indices

The amniote eggshell is a fundamental aspect of the embryo life‐support system, protecting it from UV light, microbes and mechanical damage, while regulating gas exchange and providing calcium for growth. The thickness of eggshells is highly diverse across modern birds and influences multiple eggshell functions, yet the selective pressures driving eggshell thickness have not been clearly identified. Here, we use a global dataset of avian eggshell thickness indices for 4260 (&gt; 41%) avian species to assess trends in eggshell thickness across the phylogeny, as these indices are strongly correlated with direct measures of eggshell thickness and are non‐destructive to the sample. We analysed the dataset within a phylogenetic framework to assess the relative importance of climatic and ecological explanations for variation in eggshell thickness indices. The distribution of avian eggshell thickness indices across species was found to be primarily driven by phylogenetic relatedness, in addition to evolutionary processes that do not match a Brownian model of evolution. Across modern birds, thicker eggshells were more prevalent in species (1) with precocial young, (2) which exhibit a scavenger‐based diet, (3) which primarily feed on vertebrates or plants (excluding nectivores, seed and fruit specialists) and (4) which breed in open habitats. Thicker eggshells found in species with precocial young probably enable higher rates of calcium removal for the more advanced embryo development. Excessive light transmission through the shell damages developing embryos, while too little light transmission can impede development. Eggs in shaded habitats experience low light exposure, and thus thinner shells are more prevalent in these environments potentially to increase light transmission through the shell. Overall, variation in eggshell thickness indices appears to be driven largely by phylogeny, with certain life‐history traits linked to embryo growth rate, calcium content of their food, and the need to mitigate excessive light transmission through the shell.

A molecular dynamics study on the mechanism of heterogeneous bubble nucleation of mixed liquid

The nucleate boiling of mixed boiling is widely utilized in natural gas, hydrogen liquefaction process, and other fields. In this paper, the molecular dynamics study of heterogeneous bubble nucleation of pure argon liquid and the argon‑krypton mixed liquid on the platinum surface was conducted. The nucleate boiling characteristics were presented and the variations of the density, temperature, nucleation embryo volume, and heat flux were analyzed. The difference in the nucleation mechanism of pure liquid and mixed liquid was explained based on the competition of atomic potential energy and atomic kinetic energy. The effect of the component mole fraction on the bubble nucleation of mixed fluid was also discussed. The results showed that the onset superheat of boiling of argon‑krypton mixed liquid is higher than that of pure argon. The higher the mole fraction of the component with a lower saturation temperature, the lower the onset superheat of the liquid nucleate boiling. When x < 0.5, the growth rate of the nucleation embryo is dominated by the x value, when x > 0.5, the growth rate is dominated by wall temperature. Moreover, the difference in diffusion coefficients of each component is one of the direct causes of determining the growth rate of nucleation embryos. The findings provide insights into the mechanisms of differences in boiling nucleation between mixed liquid and pure liquid, as well as guide the reasonable utilization of mixed liquid.

The identification of type I MADS box genes as the upstream activators of an endosperm-specific invertase inhibitor in Arabidopsis

BackgroundNuclear endosperm development is a common mechanism among Angiosperms, including Arabidopsis. During nuclear development, the endosperm nuclei divide rapidly after fertilization without cytokinesis to enter the syncytial phase, which is then followed by the cellularized phase. The endosperm can be divided into three spatial domains with distinct functions: the micropylar, peripheral, and chalazal domains. Previously, we identified two putative small invertase inhibitors, InvINH1 and InvINH2, that are specifically expressed in the micropylar region of the syncytial endosperm. In addition, ectopically expressing InvINH1 in the cellularized endosperm led to a reduction in embryo growth rate. However, it is not clear what are the upstream regulators responsible for the specific expression of InvINHs in the syncytial endosperm.ResultsUsing protoplast transient expression system, we discovered that a group of type I MADS box transcription factors can form dimers to activate InvINH1 promoter. Promoter deletion assays carried out in the protoplast system revealed the presence of an enhancer region in InvINH1 promoter, which contains several consensus cis-elements for the MADS box proteins. Using promoter deletion assay in planta, we further demonstrated that this enhancer region is required for InvINH1 expression in the syncytial endosperm. One of the MADS box genes, AGL62, is a key transcription factor required for syncytial endosperm development. Using promoter-GFP reporter assay, we demonstrated that InvINH1 and InvINH2 are not expressed in agl62 mutant seeds. Collectively, our data supports the role of AGL62 and other type I MADS box genes as the upstream activators of InvINHs expression in the syncytial endosperm.ConclusionsOur findings revealed several type I MADS box genes that are responsible for activating InvINH1 in the syncytial endosperm, which in turn regulates embryo growth rate during early stage of seed development.

Is the South-Mediterranean Canopy-Forming Ericaria giacconei (= Cystoseira hyblaea) a Loser From Ocean Warming?

Canopy-forming brown algae support highly productive ecosystems whose decline has been attributed to the interplay of several anthropogenic disturbances. Climate change could have disruptive effects on the biology of these species, but the role of temperature in the development of early life stages is poorly understood. The aim of this study was to assess the response of Ericaria giacconei, a winter-reproducing Southern–Mediterranean endemic species, to thermal stress by testing five temperatures (12, 15, 18, 24, and 28°C) on adults and early stages. Chlorophyll a fluorescence of adult plants was measured at 0, 24, 72, and 120 h on nine fronds in each of the three aquaria per treatment. To assess egg release, zygote settlement, and embryo growth rate, approximately 1,200 receptacles were cultured on six Petri dishes per temperature treatment, and 10 random subsections of 2 ×2 mm were examined in three Petri dishes at 0, 20, 44, and 92 h after fertilization. Adult plants showed a plastic physiological response, and thermal stress had no significant effect on PSII efficiency. Embryos fully developed only at 12 and 15°C. Mortality increased at 18 and 24°C, and no zygotes survived at 28°C. In a scenario of further increasing temperatures, the effects of warming could affect the recruitment of E. giacconei and increase its vulnerability to further stresses. These effects on the survival of early stages, which are the bottleneck for the long-term survival of the species, should be taken into account in conservation and restoration measures to maintain canopy-forming macroalgal populations and associated biodiversity and ecosystem services.

REGENERACIÓN DE PLANTAS DE Agave marmorata Roelz EN SISTEMAS DE INMERSIÓN TEMPORAL, MEDIANTE ORGANOGÉNESIS Y EMBRIOGÉNESIS SOMÁTICA

&lt;p&gt;&lt;strong&gt;Background.&lt;/strong&gt; The genus Agave has social, cultural, environmental and economic importance in Mexico. Approximately 15 species of agave are used as raw material for the production of mezcal, among them is the &lt;em&gt;Agave marmorata&lt;/em&gt; Roelz, which is considered the longest-lived agave for the preparation of this drink because its maturation period ranges from 20 to 35 years. Agave plant tissue culture is a technique that allows obtaining plants by organogenesis (O) and / or somatic embryogenesis (ES) in a short period of time. The quality and quantity of plants propagated by these methods can be favored with the use of Temporary Immersion Systems (SIT). &lt;strong&gt;Objective.&lt;/strong&gt; Establish a protocol for the regeneration of &lt;em&gt;A. marmorata&lt;/em&gt; seedlings in SIT, with the methods of direct organogenesis and indirect somatic embryogenesis. &lt;strong&gt;Methodology&lt;/strong&gt;. Two regeneration methods, direct organogenesis and indirect somatic embryogenesis, were evaluated. For the first, the effect of the frequency and number of explants grown in SIT in the sprouting and growth stages of the explant was determined. For the second, the effect of the number of explants grown in SIT on the percentage of germination and the growth rate of somatic embryos was evaluated. &lt;strong&gt;Results&lt;/strong&gt;. The best treatment in the sprouting stage was obtained with 80 explants grown in SIT with an immersion frequency of 8 h and an immersion time of 2 min, with 84% sprouting and 17.5 sprouts / explant of 1 cm in height. The best growth of the explants originated from direct organogenesis was obtained with 180 cultured explants per flask with an immersion frequency of 8 hours and an immersion time of 2 min. On the other hand, in the somatic embryogenesis method, the highest percentage of embryo germination (62.2%) was achieved with 80 somatic embryos cultured in SIT with an immersion frequency of 8 hours. &lt;strong&gt;Implications.&lt;/strong&gt; The results of this research contribute to a better understanding of the regeneration process of direct organogenesis and somatic embryogenesis in temporary immersion systems. This can help to scale the system commercially and to conserve germplasm. &lt;strong&gt;Conclusions&lt;/strong&gt;. It was possible to establish an effective protocol for the regeneration of agave seedlings.&lt;/p&gt;

The growth of super-Earths

The conditions in the protoplanetary disk are determinant for the various planet formation mechanisms. We present a framework that combines self-consistent disk structures with the calculations of the growth rates of planetary embryos via pebble accretion, in order to study the formation of super-Earths. We first perform 2D hydrodynamical simulations of the inner disks, considering a grain size distribution with multiple chemical species and their corresponding size and composition dependent opacities. The resulting aspect ratios are almost constant with orbital distance, resulting in radially constant pebble isolation masses, the mass where pebble accretion stops. This supports the “peas-in-a-pod” constraint from the Kepler observations. The derived pebble sizes are used to calculate the growth rates of planetary embryos via pebble accretion. Disks with low levels of turbulence (expressed through the α-viscosity) and/or high dust fragmentation velocities allow larger particles, hence lead to lower pebble isolation masses, and the contrary. At the same time, small pebble sizes lead to low accretion rates. We find that there is a trade-off between the pebble isolation mass and the growth timescale; the best set of parameters is an α-viscosity of 10−3 and a dust fragmentation velocity of 10 m s−1, mainly for an initial gas surface density (at 1 AU) greater than 1000 g cm−2. A self-consistent treatment between the disk structures and the pebble sizes is thus of crucial importance for planet formation simulations.

Features of growth and development of egg cross chicken embryos «Lomann Brown»

Purpose:to study morphometric parameters of absolute values of linear and weight body sizes, specific growth rate and relative (allometric) growth of chicken embryos of the «Lohmann Brown» egg cross at different stages of embryogenesis.Materials and methods.The absolute values of linear and weight body sizes of chicken embryos were estimated using morphometric methods. The formula of I. I. Schmalhausen and S. Brody was calculated the specific growth rate of length and body weight of chicken embryos by the formula simple allometry — relative (allometric) growth of body length from body mass.Results.This is manifested in the increase in the specific growth rate of body length of the embryo at 5 days of the late-fetal stage, 8th, 10th, 12th day of the early-fetal stage and specific growth rate of body mass for 6 days of the late-fetal stage of the late-fetal stage, 10-th and 12-th day of the early-fetal stage. At all stages of embryo development, there is a negative allometry of the relative growth rate of the embryo body length, except for 14 days of the mid-fetal stage, where negative isometry was observed (b=-1,000). Higher values of the power coefficient reflecting the slower growth of the embryo in length relative to their body weight, observed in late-fetal stage at 5-6 days (b=0,913-0,995), in early-fetal stage — 10-e (b=0,960) and 12 days (b=0,928), in mid-fetal stage — 13-th (b=0,821) and 15 days (b=0,981) and late-fetal stage — 20 days (b=0,836).Conclusion.New knowledge derived from this study can be applied not only in research, but in the poultry industry to assess the impact of preincubation processing of eggs on the development of embryos and embryonic mortality at different stages of embryogenesis, the definition of normal and abnormal development of embryos, as well as to assess the impact of other factors, artificial incubation on embryo development, hatchability of eggs and safety of poultry.

44 Exploring the use of silver and diamond nanoparticles on sperm cell invitro and chicken embryo in ovo

In poultry industry, chick viability is a crucial factor determining profitability from fertilized egg to placement at the farm. However, decreases in fertility and hatchability have been observed. Recently, there has been renewed interest in the use of silver nanoparticles (Ag-NPs) due to their antimicrobial properties and growth-promoting ability, and diamond nanoparticles (D-NPs) due to their biocompatibility properties. The aim of the study was to evaluate the effect of silver and diamond nanoparticles on chicken embryo oxidative status, biochemical indices, and expression of immune-related genes and on sperm cell viability. The experiment was conducted in Ross 308 chicken embryos and Ross 308 cockerels. One hundred and fifty fertilized eggs were divided randomly into 5 groups (5×30). Fertilized eggs were injected with 50 mg/L Ag-NPs at volumes of 100μL (group 1), 200μL (group 2) or 50 mg/L D-NPs at volumes of 100μL (group 3) or 200μL (group 4), or received no nanoparticles (control; group 5) and incubated at 37°C and 55% humidity for 20 days. Then, chicken blood was collected and centrifuged to evaluate alkaline phosphatase (ALP), alanine transaminase (ALT), lactate dehydrogenase (LDH), glucose, urea, and free haemoglobin. Chicken embryo liver was used to evaluate antioxidant capacity (TAC) and chicken embryo spleen was used to evaluate expression of the immune-related genes interleukin-1β (IL-1β), toll-like receptor (TLR)4, TLR2, and TLR15. Semen was randomly divided into 1 control and 8 treatment groups and treated with 50 mg/L Ag-NPs: group A (0.1ppm), group B (1ppm), group C (5ppm), group D (10ppm) or 50 mg/L D-NPs: group E (1ppm), group F (5ppm), group G (10ppm), and group H (20ppm). Sperm viability was analysed using prestoblue metabolic assay. Data were analysed using PROC in GLM procedure of SAS 2014 (SAS Institute Inc.). Decrease in sperm cell viability was recorded in a dose-dependent manner. Sperm cell viability decreased (P&amp;lt;0.005) as the concentration of Ag-NP or D-NP increased. Addition of 100μL of Ag-NPs increased the growth rate of chicken embryo but not 200μL of Ag-NPs or addition of D-NPs. Increases in ALP, ALT, LDH, glucose and urea enzyme were observed in a dose-dependent manner in both Ag-NPs and D-NPs. Addition of 50 mg/L Ag-NPs or 50 mg/L D-NPs increased (P&amp;lt;0.001) TAC of chicken embryo as the volume increased. Additions of 200μL of Ag-NPs, 100μL of D-NPs, and 200μL of D-NPs were haemolytic (P&amp;lt;0.001) but addition of 100μL of Ag-NPs was not. Additions of 100 or 200μL of Ag-NPs or 100μL of D-NPs downregulated IL-1β and 200μL of D-NPs upregulated IL-1β compared with the untreated control group. Additions of 100 or 200μL of Ag-NPs or 200μL of D-NPs induced expression of TLR4 and TLR15. Furthermore, addition of Ag-NPs did not result in expression of TLR2. We concluded that administration of 50 mg/L Ag-NPs and 50 mg/L D-NPs in ovo improve immune status and administration of 100μL of Ag-NPs improved the growth rate of chicken embryo. However, toxicity associated with 50 mg/L Ag-NPs and 50 mg/L D-NPs remains a concern and need to be addressed before use.

İzole Teratozoospermi Grubu Hastalarda Sperm Dna Fragmantasyonu ve Maturasyonu Sonuçlarının Sperm Morfoloji Sonucu Normal Olan Hasta Grubu ile Embriyo Gelişim ve Gebelik Oranlarının Karşılaştırılması

İzole Teratozoospermi Grubu Hastalarda Sperm Dna Fragmantasyonu ve Maturasyonu Sonuçlarının Sperm Morfoloji Sonucu Normal Olan Hasta Grubu ile Embriyo Gelişim ve Gebelik Oranlarının Karşılaştırılması

Earlyembryonic development in prolific Meishan pigs

Prenatal mortality in European pigs is estimated at 30-40%, the majority of which occurs between days 12 and 18 after mating. Chinese Meishan pigs are prolific, averaging three to five more pigs per litter than do European breeds. Early reports into the fecundity of Meishan females suggested that their prolificacy resulted from lower embryonic mortality when compared with European females exhibiting the same ovulation rate. The preponderance of evidence suggests that there are no differences between Meishan and European breeds in either morphological embryo diversity within a litter or embryo mortality before day 12 after mating. Recent studies from our laboratory suggest that preimplantation embryos from Meishan females exhibit markedly reduced growth rates and oestrogen secretory activities through day 12 when compared with embryos from Yorkshire females. The significantly reduced conceptus sizes of Meishan versus European breeds on day 30 of gestation provide additional evidence of the reduced growth rate of Meishan embryos. Furthermore, because embryonic oestrogen production is known to alter uterine secretion of histotroph, the lower oestrogen production by Meishan embryos in the Meishan uterus may result in more gradual alterations in the uterine environment that are beneficial for conceptus survival and subsequent litter size. Recent studies using cross-transfer of Meishan and Yorkshire embryos on day 2 after mating have led to the suggestion that there is a major effect of recipient genotype on embryonic growth rate and oestrogen secretion. In these studies, both Meishan and Yorkshire embryos transferred to Meishan uteri exhibited marked decreases in morphological development and oestrogen content on day 12 when compared with embryos transferred to Yorkshire recipients. These data suggest the presence of factor(s) in endometrial secretions from Meishan females that reduce the growth rate and oestrogen secretory potential of preimplantation conceptuses.

Multiphase modelling of the growth kinetics of precipitates in Al-Cu alloys during artificial aging

ABSTRACT In the aluminum industry, the needs of predictability of the kinetics of precipitation during the artificial aging processes increase as the targeted applications require the maximisation of properties at the lowest costs possible. In this regard, kinetics modelling can be helpful to design the heat treatment processes. Despite using many fitting parameters, available models show a lack of fitting with experimental data, especially for the apparent heat capacity measured at high temperatures by a differential scanning calorimeter (DSC). To address this issue, a mixed-mode model was recently developed for isothermal heat treatment, whereas non-isothermal heat treatment must be considered to compare the calculated results with those measured by isochronal heating in a DSC. In this contribution, the model is extended to non-isothermal heat treatments. To this end, the growth kinetics pathway and sequence of precipitation in a binary Al-Cu alloy have been simulated, optimising the pre-exponential factor and the activation energy of the interfacial mobility of the secondary phases. This calibration of the interfacial mobilities allowed a very good reproduction of the evolution of the apparent heat capacity with temperature. The model and calibrated interfacial mobilities were then used to compute the size evolution of θ′ precipitates in an Al-4 wt%Cu. The isothermal growth rates calculated at 4 temperatures were in good agreement with those measured and reported by independent researchers. The good predictability of the model indicates that the assumptions made were suitable and well funded, especially regarding the growth rates of embryos emerging from the subcritical growth regime.