Fertilization Rate Research Articles

Yield and nutrient use efficiency of sorghum-sudangrass hybrid plant under different NPK fertilization rates

Yield and nutrient use efficiency of sorghum-sudangrass hybrid plant under different NPK fertilization rates

Impact of formulated organic fertilizers on soil physical and chemical properties in sandy loam soil of North-Eastern Nigeria

The excessive and sole use of inorganic fertilizers has led to soil nutrient depletion, acidification and loss of soil organic matter. Decreased organic matter content reduces the soil's ability to hold water and nutrients, which can lead to reduced crop yields. Organic fertilizers provide a slow release of nutrients to soil while at the same time improving soil health and reducing the risk of soil degradation. Hence, there is a need to investigate the impact of formulated organic fertilizers on soil physical and chemical properties in the study area. The study site is in the Teaching and Research Farm, Yobe State College of Agriculture, Science and Technology Gujba, Damaturu, Yobe State. Its geographic coordinates are 11.7461° N, 11.9608°. The study area is approximately twenty hectares while the size of land for the experiment was approximately two hectares. The soil analysis conducted revealed varying levels of nutrients. Nitrogen (N) ranged from 0.11 to 0.20 g/kg-1, indicating medium fertility. Phosphorus (P) levels ranged from 0.17 to 0.19 g/kg-1, indicating signifying low fertility, while potassium (K) varied from 0.46 to 0.89 g/kg-1, indicating high fertility. Copper (Cu) levels ranged from 0.67 to 0.85 g/kg-1, suggesting medium fertility. Zinc (Zn) ranged from 0.55 to 0.38 g/kg-1, indicating medium to low fertility, particularly in deeper soil layers. Iron (Fe) ranged from 0.53 to 0.01 g/kg-1, categorized as medium to low fertility. Manganese (Mn) ranged from 0.11 to 0.04 g/kg-1, showing low fertility levels insufficient for optimal agricultural production. Despite minor improvements post-application of organic fertilizer, overall fertility ratings remained largely unchanged. The study highlights the heterogeneous distribution of nutrients in the study area, emphasizing both strengths and deficiencies crucial for agricultural productivity.

Optimizing Fertilization Strategies to Promote Leaf-Use Ginkgo Productivity and Ecosystem Economic Benefits: An Integrated Evaluation of a Field Trial in Southern China

Field experiments were conducted on a four-year-old leaf-use ginkgo plantation in southern China to assess the impact of nine different fertilization strategies with varying N-P2O5-K2O rates at three growth phases (FBD: March for bud development; FLG: May for leaf growth; FLS: July for leaf strengthening) on leaf-use ginkgo (Ginkgo biloba L.) leaf productivity and ecological economic benefits (EEBs). The results indicated that regardless of timing and rate, fertilizer application led to an increase in leaf area and thickness, resulting in higher ginkgo leaf yield. The highest fresh (215.14 g tree−1) and dry (78.83 g tree−1) yields were observed with 3 g N + 2.5 g P2O5 + 1.5 g K2O tree−1 in FLG. FLS was found to mitigate the decline in SPAD values of leaves during late summer. Furthermore, fertilized ginkgo trees exhibited higher flavonoid concentrations in leaves, enhancing profitability. However, higher fertilizer rates were associated with elevated greenhouse gas emissions, nitrogen losses and ecological costs. Despite these drawbacks, all fertilization treatments resulted in increased net economic income. Specifically, compared to no fertilization, FBD, FLG and FLS treatments boosted net income by 3.5~26.6%, 11.6~60.5% and 5.8~35.4%, respectively. Using the entropy weight TOPSIS method, it was concluded that optimizing the N, P and K fertilization rate and timing (applying 3–2.5–1.5 g tree−1 of N-P2O5-K2O in May) is a beneficial approach to maximize EEBs and industrial benefits in leaf-use ginkgo plantations in southern China. This study provides valuable insights into suitable fertilization patterns and management for leaf-use ginkgo plantations in southern China.

Nitrogen fertilization timing and rate influence N recovery efficiency and rice yield

AbstractNitrogen (N) fertilizer management in rice (Oryza sativa L.) varies with production practices. In drill‐seeded, delayed‐flood production systems, the most common production practice in Louisiana N fertilizer is applied at two application timings. The first application timing is just before the permanent flood is established. The second application is at midseason. Nitrogen fertilization before flooding is critical for maximum N uptake, nitrogen recovery efficiency (NRE), and yield. Field experiments were conducted from 2017 to 2020 to evaluate N timing effects on N uptake, NRE, and rice yield. The rice cultivar CL153 was drill‐seeded into a stale seedbed at a seed rate of 85 kg ha−1. Fertilizer‐N was applied utilizing multiple application timings and rates adding up to a seasonal rate of 155 kg ha−1 across treatments. A single N application 1‐day before flooding significantly increased grain yield in all trials, ranging from 8523 kg ha−1 in 2019 to 11,322 kg ha−1 in 2018. Compared to post‐flood applications, preflood N increased plant height, N uptake, and NRE. Split N application rates and timings after flooding did not impact rice yield or its agronomics, such as height, aboveground biomass, and time of heading. NRE and yield were significantly correlated (r = 0.805; p < 0.001). Our results indicated that a single N application before flooding has the potential to be an alternative option for N management in the drill‐seeded, delayed‐flood rice system.

Penerapan Green Water System (GWS) terhadap Hatching Rate Telur Ikan Lele Sangkuriang (Clarias Gariepinus)

Increasing catfish seed production sustainably is important to meet market needs. One effort to increase seed production is through the degree of egg hatching. This study aims to test the effectiveness of the application of the green water system on the success of hatching sangkuriang catfish eggs. The method used in this study was an experiment with two levels of treatment and 3 replications. The results of the study from the spawning of a pair of parents, obtained an average fertilization rate value produced in the GWS pond of 96.6% and the control pond 97.4%. In addition, the hatching rate showed a difference, with an average in the GWS pond of 90.6% while in the control pond 78.3%. The difference in the degree of egg hatching in the GWS pond can be associated with several factors, such as the availability of higher dissolved oxygen. Dissolved oxygen in the GWS pond is higher through the process of photosynthesis. Chlorophyceae is the most abundant phytoplankton found in the GWS hatching pond. Based on the research results, it can be concluded that the implementation of the Green Water System is effective in increasing the hatching of sangkuriang catfish eggs with an HR of 90.6%. This can be an alternative technology that is useful for cultivators to increase seed production.

High risk of low birth weight in couples with advanced paternal age in in vitro fertilization treatment.

With the development of socio-economic conditions and a shift in attitudes towards fertility, there has been a gradual increase in delayed childbearing since the 2000s. Ageplays a significant role in the decline of fertility. However, we know very little about the association of paternal age with reproductive outcomes. To investigate the correlation between advanced paternal age and semen quality, embryo quality, pregnancy, and neonatal outcomes in IVF cycles. In this study, after excluding female partners aged ≥35 years, we analyzed data from 761 infertile couples who underwent in vitro fertilization cycles at the First Affiliated Hospital of USTC between June 2020 and March 2023. Cases were classified into three groups according to the age of the male: <35 years (530 infertile couples), 35 years ≤ paternal age <40 years (125 infertile couples), and ≥40 years (106 infertile couples). Then, we compared the general clinical data arising from in vitro fertilization cycles between the three groups, including semen parameters, embryonic parameters, and pregnancy and neonatal birth outcomes. Data analysis showed that the duration of infertility and the incidence of secondary infertility were significantly higher in paternal age ≥35 years groups than those aged <35 years (all p<0.05). We also observed a significant difference between ≥40 years and <35 years groups in terms of the normal fertilization rate, high-quality embryo rate, clinical pregnancy rate, miscarriage rate, live birth rate, Apgar scores, and the low birth weight neonatal rate (all p<0.05). The group with paternal age ≥40 years showed statistically significant differences in terms of clinical pregnancy rate, miscarriage rate, live birth rate, and low birth weight on multivariable logistic regression (all p<0.05). The results of our study indicate that advanced paternal age (≥40 years) has a significant impact on the embryo quality, pregnancy outcome, and neonatal outcome. Paternal age over 40 years is a risk for in vitro fertilization success rate.

Inductive cum targeted yield model-based integrated fertilizer prescription for sweet corn (Zea mays L. Saccharata) on Alfisols of Southern India.

Striking the right nutrient balance is essential for sustainable farming and ecosystem health. In this regard, field experiments were conducted in three phases viz., fertility gradient experiment, main experiment and validation experiment through a soil test crop response approach to develop and validate fertilizer prescription equations for sweet corn in comparison with general recommended dose and soil fertility rating approach. The soil data, fresh cob yield, and NPK uptake were used for establishing four important basic parameters, viz., nutrient requirement (kg t-1), contribution of nutrients from fertilizers, soil, and organic manure. The results revealed that nutrients required to produce one tonne of fresh cob yield (NR) were 5.85 kg, 0.87 kg and 4.31kg for N, P and K, respectively under the STCR NPK alone approach and 6.07 kg, 0.92 kg and 4.33 kg for N, P and K, respectively under STCR NPK+FYM approach. In the validation experiment, STCR NPK+FYM approach for the targeted yield of 25 t ha-1 recorded higher fresh cob yield (23.38 t ha-1) and dry stover yield (35.07 t ha-1) which were significantly higher compared to general recommended dose and soil fertility rating approach. The developed STCR equations for the aforesaid crop are valid as the percent deviation of cob yield from the targeted yield was within ±10%. Similarly, highest nutrient use efficiency was achieved with the STCR approach, specifically when targeting a lower yield through an NPK+FYM mode. Thus, implementation of the STCR approach of fertilizer prescription, with or without FYM, at targeted yields of 25 and 22 t ha-1, not only surpassed the effects of the other fertilizer recommendation approach in terms of cob yields, but also increased NPK uptake, improved nutrient use efficiency and greater economic returns.

Calibration and validation of APISM-Wheat Model in Mediterranean areas

The Agricultural Production Systems sIMulator-Wheat (APSIM-Wheat) model is one of the most widely used agricultural models. It is a powerful simulator that has been successfully calibrated and tested for many locations in the world, especially in Western Australia (WA). However, there is a noticeable lack of a standard guide for realizing the calibration validation of APSIM-Wheat that could be applied in areas with a Mediterranean climate similar to that of WA. Therefore, this study aims to examine crop simulations reported in published articles and to provide a detailed description of input data and statistical assessment, which represent the two main components of the calibration-validation protocols. The PRISMA (PREFERRED Reporting Items for Systematic Reviews and Meta-Analyses) method was used to identify and select relevant papers for this review. Following the analysis of 31 calibration protocols extracted from selected eligible articles, it was found that regardless of the objective of using APSIM-Wheat, the same category of data is required for calibration. As far as meteorological data is concerned, the information essential to this study was daily maximum and minimum air temperatures, rainfall (mm), and solar radiation. In the case of soil data, information about the texture and hydraulic characteristics, especially PAWC, DUL and LL was required. Regarding agricultural management data, this pertains to cultivated crops, Nitrogen fertilization (rate and time of application) and sowing (date and density). For the statistical evaluation, it was observed that 90 percent of studies analyzed in this review revealed the use of RMSE.

Microplastic Leachate Negatively Affects Fertilization in the Coral Montipora capitata.

Microplastic pollution is an emerging stressor of concern to coral reef ecosystems which are already threatened by additional global and local level anthropogenic stressors. The effects of ingesting microplastics alone on corals have been well studied, but the effects of the chemical composition of these particles have been understudied. Many microplastic-associated chemicals are endocrine disrupters potentially posing a threat to organismal reproduction. Therefore, the goal of this study was to determine if differences exist between the effects of microplastics themselves and plastic leachate on Montipora capitata fertilization due to changes in fatty acid quantity and composition. Assays were conducted two years in a row which exposed M. capitata gamete bundles to either one of four types of recently manufactured, virgin microspheres (nylon, polypropylene, high-density polyethylene, or low-density polyethylene) at three concentrations (50, 100, or 200 particles/L) or microplastic leachates, presumably including plastic additives from these microspheres. Gamete fertilization was not impacted by plastic particles themselves, but some of the microplastic leachate treatments with the same polymer type significantly reduced fertilization rates for M. capitata. Additionally, a total of 17 fatty acids were seen in both years, but neither fatty acid quantity nor composition correlated with observed declines in fertilization. Instead, fertilization and fatty acid data independently varied by concentration and polymer type, likely due to the presence of different chemicals. This study is the first to directly test the toxicity of plastic leachate to coral reproduction. These findings show that microplastic-associated chemicals are an important stressor affecting successful coral fertilization and fatty acid quantity and composition and provide evidence for the negative effects of microplastic leachate to coral reproduction. Thus, plastic additives could pose an additional threat to coral replenishment and persistence in coral reef ecosystems.

Assessing reproductive effects and epigenetic responses in Austrolebias charrua exposed to Roundup Transorb®: Insights from miRNA profiling and molecular interaction analysis

This study examines the effects of Roundup Transorb® (RDT) exposure on reproductive functions and ovarian miRNA expression in Austrolebias charrua. Exposure to RDT (at 0.065 or 5 mg. L−1 for 96 h) significantly disrupts fertility, evidenced by changes in fertilization rates and egg diameter. Profiling of ovarian miRNAs identified a total 205 miRNAs in A. charrua. Among these, three miRNAs were upregulated (miR-10b-5p, miR-132–3p, miR-100–5p), while ten miRNAs were downregulated (miR-499–5p, miR-375, miR-205–5p, miR-206–3p, miR-203a-3p, miR-133b-3p, miR-203b-5p, miR-184, miR-133a-3p, miR-2188–5p) compared to non-exposed fish. This study reveals that differentially expressed miRNAs are linked to molecular pathways such as steroid hormone biosynthesis, lipid and carbohydrate metabolism, bioenergetics, and antioxidant defense. It also analyzes molecular interactions between miRNAs and target genes during RDT exposure in annual killifish, providing insights into biomarkers in ecotoxicology. Moreover, it provides scope for developing environmental health assessment models based on epigenomic endpoints, supporting the protection of biodiversity and ecosystem services through the quantification of stress responses in living organisms exposed to pesticides.

Reducing nitrogen fertilizer applications mitigates N2O emissions and maintains sugarcane yields in South China

Fertilizer N application combined with crop residue retention and a warm and humid climate increases nitrous oxide (N2O) emissions from sugarcane systems. However, the effects of high fertilizer N application rates on N2O emissions from sugarcane fields in China and the N2O reduction potential are still unclear. This study measured N2O emissions, the δ15N values for N2O and soil mineral N (NH4+ and NO3–), and yields during three continuous growing seasons in a sugarcane field in subtropical South China when four fertilizer N application rates: 0 (N0), 300 (N300), 400 (N400), and the local conventional rate of 500 kg N ha–1 (N500), were applied. The results showed that N2O emissions peaked in the first 4 weeks after fertilizer N application and the peak amplitude was highest after applying the N500 rate. The greatest soil N2O fluxes occurred when soil NH4+ and NO3– contents were high, the soil pore spaces contained large amounts of water (around 60 %), and there was a high soil surface temperature (around 35°C). The cumulative N2O emissions over the whole season (1.3–64.8 kg N ha–1) and emission factor values (2.6–11.1 %) both strongly increased with fertilizer N rate. The δ15N values for N2O and soil NH4+ and NO3– indicated that N2O production after N fertilization was dominated by denitrification and the microbial types varied with time and N fertilization rate. The principal component analysis showed that the factors associated with denitrification and nitrification explained 53.53 % and 30.53 % of the variation in N2O fluxes, respectively. Sugarcane yields, N uptake, and sugar contents were not affected by the reduced fertilizer N rates (N400 and N300) compared to that of N500. A reasonable N fertilizer rate of around 340 kg N ha–1 could reduce N2O emissions by more than 65 % compared to the conventional N500 rates while maintaining sugarcane yields. This study quantified the N2O emissions induced by different fertilizer N rates in a sugarcane system in China and highlighted the considerable potential for reducing N2O emissions through optimization of the fertilizer N application rate.

Non-Obstructive Azoospermia and Intracytoplasmic Sperm Injection: Unveiling the Chances of Success and Possible Consequences for Offspring.

Non-obstructive azoospermia (NOA) is found in up to 15% of infertile men. While several causes for NOA have been identified, the exact etiology remains unknown in many patients. Advances in assisted reproductive technology, including intracytoplasmic sperm injection (ICSI) and testicular sperm retrieval, have provided hope for these patients. This review summarizes the chances of success with ICSI for NOA patients and examines preoperative factors and laboratory techniques associated with positive outcomes. Furthermore, we reviewed possible consequences for offspring by the use of ICSI with testicular sperm retrieved from NOA patients and the interventions that could potentially mitigate risks. Testicular sperm retrieved from NOA patients may exhibit increased chromosomal abnormalities, and although lower fertilization and pregnancy rates are reported in NOA patients compared to other forms of infertility, the available evidence does not suggest a significant increase in miscarriage rate, congenital malformation, or developmental delay in their offspring compared to the offspring of patients with less severe forms of infertility or the offspring of fertile men. However, due to limited data, NOA patients should receive specialized reproductive care and personalized management. Counseling of NOA patients is essential before initiating any fertility enhancement treatment not only to mitigate health risks associated with NOA but also to enhance the chances of successful outcomes and minimize possible risks to the offspring.

Association between Exposure of Rare Earth Elements and Outcomes of In Vitro Fertilization-Embryo Transfer in Beijing

Objective The study aimed to investigate the impact of rare earth elements (REEs) exposure on pregnancy outcomes of in vitro fertilization-embryo transfer (IVF-ET) by analyzing samples from spouses.Methods A total of 141 couples were included. Blood and follicular fluid from the wives and semen plasma from the husbands, were analyzed for REEs using inductively coupled plasma mass spectrometry (ICP-MS). Spearman's correlation coefficients and the Mann–Whitney U test were used to assess correlations and compare REE concentrations among three types of samples, respectively. Logistic models were utilized to estimate the individual REE effect on IVF-ET outcomes, while BKMR and WQS models explored the mixture of REE interaction effects on IVF-ET outcomes.Results Higher La concentration in semen (median 0.089 ng/mL, P = 0.03) was associated with a lower fertilization rate. However, this effect was not observed after artificial selection intervention through intracytoplasmic sperm injection (ICSI) (P = 0.27). In semen, the REEs mixture did not exhibit any significant association with clinical pregnancy.Conclusion Our study revealed a potential association between high La exposure in semen and a decline in fertilization rate, but not clinical pregnancy rate. This is the first to report REEs concentrations in follicular fluid with La, Ce, Pr, and Nd found at significantly lower concentrations than in serum, suggesting that these four REEs may not accumulate in the female reproductive system. However, at the current exposure levels, mixed REEs exposure did not exhibit reproductive toxicity.

Balancing Yield and Environmental Impact: Nitrogen Management and Planting Density for Rice in Southwest China

With growing concerns about global warming, it is crucial to adopt agronomic practices that enhance rice yields from paddy fields while reducing greenhouse gas (GHG) emissions for sustainable agriculture. An optimal nitrogen (N) fertilization rate and planting density are vital to ensure high rice yields, minimize GHG emissions, and understand emission behavior for better field management. We hypothesized that optimizing N application rates and planting density to improve nitrogen use efficiency (NUE) in rice cultivation would reduce resource losses and GHG emissions. To test this hypothesis, we implemented five treatments with a rice straw return cultural system: two planting densities (16 hills m−2 (traditional density, D1) and 20 hills m−2 (25% higher density, D2)) and three N application rates (no N fertilizer (N0), 180 kg N ha−1 (N1), and 144 kg N ha−1 (N2)). The control treatment (CK) was traditional planting density with no N fertilizer. The four new cropping modes were N1D1, N1D2, N2D1, and N2D2. We investigated the effects of N application rates and planting density on rice grain yield, NUE, and GHG emissions in multiple rice-growing seasons. The N1D2 treatment exhibited the highest grain yield over the three years, with a value of 10,452 kg ha−1, representing an increase of 12.2% compared to CK. Moreover, N uptake in N1D2 was the highest, averaging 39.2% (p &lt; 0.05) higher than CK, and 8.5%, 3.5%, and 2.8% (p &lt; 0.05) higher than N1D1, N2D1 and N2D2, respectively. N2D2 exhibited the highest NUE, with a value of 58.99 kg kg−1, surpassing all other treatments over the three years. GHG emissions, global warming potential (GWP), and greenhouse gas intensity (GHGI) in N2D2 were lower than in N1D1, N1D2, and N2D1. Additionally, reducing N application (comparing N1D1 to N2D1) and increasing plant density (comparing N1D1 to N1D2) improved N agronomic efficiency (NAE) and N partial productivity (PFPN). The negative correlation between the NAE and PFPN with GWP and GHG emissions further supports the potential for optimized N management and denser planting density to reduce environmental impact. These findings have important implications for sustainable rice cultivation practices in Southwest China and similar agroecosystems, emphasizing the need for integrated nutrient management strategies to achieve food security and climate change mitigation goals.

GnRH agonist-only trigger, compared to dual trigger, reduces oocyte retrieval rate in high responders without affecting cumulative live birth rate.

This study compared, in high responders undergoing IVF treatment, GnRH agonist-only trigger and dual trigger on oocyte retrieval rate and cumulative live birth rate (LBR). The aim was to determine if the GnRH agonist-only triggers had provided outcomes comparable to dual trigger, while minimizing the risk of ovarian hyperstimulation syndrome (OHSS). A retrospective, matched case-control study was conducted at Taichung Veterans General Hospital, Taiwan, including women who underwent IVF/ICSI between January 1, 2014, and December 31, 2022. Inclusion criteria were: GnRH antagonist protocol and estrogen level >3,000 pg/ml on trigger day. Exclusion criteria were: immune/metabolic diseases, donated oocytes, and mixed stimulation cycles. Propensity score matching was applied to balance age, AMH level, and oocyte number between the GnRH agonist-only and dual trigger groups. Outcomes were analyzed for patients who had complete treatment cycles, focusing on oocyte retrieval rate and cumulative LBR. We analyzed 116 cycles in the agonist-only group, and 232 cycles in the dual trigger group. No inter-group difference was found in their age, BMI, and AMH levels. The dual trigger group had a higher oocyte retrieval rate (93% vs. 80%; p <0.05), while fertilization rates, blastocyst formation rates, and cumulative LBR were comparable. Notably, no OHSS cases had been reported in the GnRH agonist-only group, compared with 7 cases in the dual trigger group. GnRH agonist-only triggers resulted in a lower oocyte retrieval rate compared to dual triggers but did not significantly affect cumulative LBR in high responders. This approach effectively reduces OHSS risk without compromising pregnancy outcomes, making it a preferable option in freeze-all strategies, despite a longer oocyte pick-up duration and a medium cost. GnRH agonist-only trigger, however, may not be suitable for fresh embryo transfers or patients with low serum LH levels on trigger day.

Medaka (Oryzias latipes) Dmrt3a Is Involved in Male Fertility.

Research across various species has demonstrated that the doublesex and mab-3-related transcription factor 3 (dmrt3) plays pivotal roles in testis development. However, the precise molecular mechanisms of dmrt3 remain unclear. In this study, we investigated the role of dmrt3 (dmrt3a) in testis development using the model organism medaka (Oryzias latipes). SqRT-PCR and ISH analyses revealed that dmrt3a is predominantly expressed in the testis, especially in the spermatid and spermatozoon. Using CRISPR/Cas9, we generated two dmrt3a homozygous mutants (-8 bp and -11 bp), which exhibited significantly reduced fertilization rates and embryo production. Additionally, the number of germ cells and sperm motility were markedly decreased in the dmrt3a mutants, manifesting as the symptoms of asthenozoospermia and oligozoospermia. Interestingly, RNA-Seq analysis showed that the deficiency of dmrt3a could lead to a significant downregulation of numerous genes related to gonadal development and severe disruptions in mitochondrial function. These results suggested that dmrt3a is essential for spermatogenesis and spermatozoa energy production. This paper provides new insights and perspectives for further exploring the molecular mechanisms underlying spermatogenesis and addressing male reproductive issues.

Effect of Synthetic Hormone on Breeding Potential of Gold Fish (Carassius auratus)

The acquisition of ornamental fish is becoming a prerequisite for luxury. Fish which are ornamental are getting progressively more popular as a way to alleviate stress. Among these, goldfish and koi carp are the most prevalent visually appealing fish that happen to be consistently in demand by fish hobbyists. For millennia, the method of raising these fish has been standardized. One of the most significant advancements in the aquaculture of ornamental fish that are vital to economic prosperity is artificial propagation. Induced breeding is a straightforward approach that guarantees a timely supply of seed spawn for fish culture. The aim of the current study was to use ovaprim™ hormone at various dosages to encourage breeding in gold fish (Carassius auratus auratus) kept in captivity. Every breeding pair, including the control, was bred. There were significant (&lt;0.05) variations in the success of fertilization and hatching rate at various doses between treatments and the control group. Ovaprim™ at a dose of 0.7ml/kg and 1.4ml/Kg was found to be effective for male and female respectively with 54% fertilization rate, 43 % hatching rate. The positive response to synthetic hormone (ovaprim™) with considerable fertilization and hatching rate makes it possible to conduct the breeding program of this species commercially and the method can be applicable for commercial culture.

Heat stress mediates toxicity of rutile titanium dioxide nanoparticles on fertilisation capacity in the broadcast spawning mussel Mytilus galloprovincialis

Titanium dioxide nanoparticle (nTiO2) pollution of marine environments is rapidly increasing with potentially deleterious effects on wildlife. Yet, the impacts of nTiO2 on reproduction remain poorly understood. This is especially the case for broadcast spawners, who are likely to be more severely impacted by environmental disturbances because their gametes are directly exposed to the environment during fertilisation. In addition, it is unclear whether rising water temperatures will further exacerbate the impact of nTiO2 toxicity. Here, in a series of fertilisation trials, we systematically examine the main and interactive effects of nTiO2 exposure and seawater temperature on fertilisation success in the Mediterranean mussel Mytilus galloprovincialis. Specifically, our fertilisation trials explored whether nTiO2 exposure influences fertilisation rates when (i) eggs alone are exposed, (ii) both sperm and eggs are exposed simultaneously, and (iii) whether increases in seawater temperature interact with nTiO2 exposure to influence fertilisation rates. We also ask whether changes in nTiO2 concentrations influence key sperm motility traits using computer-assisted sperm analysis (CASA). In fertilisation trials for treatment groups (i) and (ii), we found no main effects of nTiO2 at environmentally relevant concentrations of 5, 10 and 50 μg L−1 on fertilisation capacity relative to the control. Consistent with these findings, we found no effect of nTiO2 exposure on sperm motility. However, in treatment group (iii), when fertilisation trials were conducted at higher temperatures (+6 °C), exposure of gametes from both sexes to 10 μg L−1 nTiO2 led to a reduction in fertilisation rates that was significantly greater than when gametes were exposed to elevated temperature alone. These interacting effects of nTiO2 exposure and seawater temperature demonstrate the toxic potential of nTiO2 for fertilisation processes in a system that is likely to be impacted heavily by predicted future increases in sea surface temperatures.

Preterm birth in young women and singleton pregnancy following IVF in the kingdom of Bahrain

Invitro Fertilization (IVF) rate has been constantly increasing since 1986. Preterm birth is a known complication of IVF pregnancies. Analysis of the risk of preterm birth in young mothers conceived singleton pregnancy through IVF/Intra cytoplasmic sperm injection (ICSI) is an important assessment to counsel young patients contemplating IVF treatment.This is a retrospective analysis of births from young patients of ≤35 years, following natural/ IVF conception between January 2019 and February 2020 at Bahrain Defense Force Hospital. We studied the women who had conceived through ART (Assisted Reproductive Technology) against women conceived naturally. Preterm birth between 24 and 37 weeks of gestation was analyzed. The risk factors for preterm delivery such as multiple pregnancy, placental insufficiency, vaginal infections as well as iatrogenic preterm deliveries were analyzed. P-Value&amp;#60;0.05 is considered statistically significant.The study included 2646 women. IVF conception was reported in 56 patients with rate of 2.1%. Our study showed that gestational age at delivery was earlier for IVF conception at 36.5 weeks compared to 39 weeks for natural conception. Multiple logistic regression analysis after adjusting other risk factors of preterm delivery, confirmed increased risk of delivery before 37 weeks after IVF singleton conception with OR 2.3 and 95% CI(1.1-4.7) P = 0.02. Risk of delivery before 32 weeks not increased with IVF conception OR 2.3 with 95% CI of 0.9-5.9 P=0.09, but the risk significantly increased for delivery before 28 weeks with OR 4.5 with 95% CI(1.2-16.8)P=0.02.Preterm deliveries are significantly increased in women aged less than 35 years old after IVF/ICSI with singleton pregnancies.

Standardized Sperm Cryofreezing Technique for Caspian Sea Sturgeons (Huso huso, Acipenser persicus, Acipenser stellatus, Acipenser nudiventris)

Sturgeons, considered `living fossils,` face extinction due to various factors, according to the International Union for Conservation of Nature's Red List. The present study describes a uniform sperm cryopreservation method for the endangered Caspian Sea sturgeon species, which are beluga (Huso huso), Persian (Acipenser persicus), stellate (Acipenser stellatus), and ship (Acipenser nudiventris) sturgeons for both artificial reproduction and ex-situ conservation attempts. For this aim, sperm samples were diluted 1:1 in extender composed of 118 mM Tris buffer (pH=8) and 23.4 mM sucrose-based extender containing 15% DMSO and equilibrated for one hour at 4°C. Then, sperm samples were placed into 0.50-ml straws and multi-stage cooling was applied to freeze with the help of a programmable freezer with an accuracy of ±0.1C/min, and finally stored in liquid nitrogen (-196C) tank. Thawing was performed at 40°C water baths for 25 s. The results indicated that storage for two years resulted in a 24.7% fertilization rate for the stellate sturgeon, while the Persian sturgeon had a remarkable rate of 58.2% after five years storage.