Fertilization Of Eggs Research Articles

Don't Stand So Close: Social Crowding Negatively Impacts Reproduction in an Endangered, Territorial Hawaiian Bird

ABSTRACTConservation breeding programs (CBPs) can play a vital role in preventing extinction. Housing considerations are particularly important in CBPs because suboptimal enclosures can negate efforts to promote animal well‐being, survival, reproduction, and the retention of natural behaviors. Moreover, the quality and quantity of enclosures also influence the social environment experienced by animals, an important determinant of reproduction. Extinct in the wild, the territorial ‘Alalā (Hawaiian crow, Corvus hawaiiensis) is the subject of intensive conservation breeding at two purpose‐built facilities in Hawai'i. To examine the role of space and social environment in this CBP, we evaluated reproductive outcomes for ‘Alalā pairs held in different‐sized enclosures (i.e., housed in one vs. two chambers within a stand‐alone aviary building), corresponding to important differences in social context, including the amount of space and enclosure architecture available for the pair, which we label “social crowding.” We tested the hypothesis that social crowding adversely impacts nest quality, clutches laid, egg fertilization, and hatching success. We found social crowding negatively impacted nest quality and decreased the probability of clutch production, suggesting that stress, derived from being housed in a social arrangement that does not align with the territorial nature of ‘Alalā, may compromise reproductive behavior and/or physiology. We did not find statistical evidence that crowding affected egg fertilization or hatching success, thus the impacts of crowding appear to manifest during the earlier reproductive stages. Broadly, our findings underscore the importance of aviary design and social context in avian CBPs and raise concerns about reduced breeding output due to housing territorial birds in smaller enclosures with denser social arrangements. Furthermore, our findings can guide decisions about strategic housing of pairs in aviaries and identify solutions that mitigate the consequences of social crowding on reproductive success.

Exposure to copper metal enhances the tolerance of An. gambiae s.s. over multiple generations while reducing both fertility and fecundity in this primary malaria vector.

Background Anopheles s.l. displays the potential to develop tolerance to heavy metals, particularly copper, this may occur at a significant biological cost, which can adversely affect its ecological fitness. This study investigated the larval metal exposure on larval development and reproduction of An. gambiae s.s., a laboratory susceptible strain, kisumu. Methods Stage 2 larvae of Anopheles gambiae, Kisumu were exposed to C1 = 484 μg L-1, C2 = 300 μg L-1 and 0 μg L-1 (control) of copper chloride. Larval mortality, pupation time, pupation rate, gonotrophic cycle length, fecundity and fertility of larvae/adults were assessed over six generations. Results Results revealed that larval mortality rate was significantly higher in the C1 groups of each group (p = 0.000), but this mortality rate decreased over generations. Pupation time was extended to 13 and 14 days respectively for C2 and C1 groups (p = 0.000) compared to the control group. Similar results were observed for the gonotrophic cycle, which increased from 4 days at G0 to more than 6 days at generation 5 in adults of C1. The pupation rate in generation 4 (C1) and generation 5 of the same group (p = 0.000) as well as the emergence rate in generation 4 (C2, p = 0.000) and generation 5 (C1 and C2, p = 0.000) decreased significantly compared to the control group. The average number of eggs laid was lower in the test groups from generation 4 to generation 5 (C1 and C2, p = 0.00) and egg fertility was also negatively affected by exposure of the larval stage of An. gambiae s.s. to copper. Conclusion This study showed that copper not only exhibits larvicidal properties in Anopheles gambiae s.s. larvae, it also revealed the potential of this metal to reduce fecundity and fertility in these malaria vectors.

The effect of breeder body mass on laying performance, egg quality, and hatching traits of Japanese quail.

Aim of study: The aim of this research was to determine the effect of breeder body mass on egg laying performance, egg quality, and hatching traits of Japanese quail (Coturnix japonica). Area of study: This study was carried out at the Poultry Unit and Research Centre of Çukurova University in the Republic of Türkiye. Material and methods: In this study, a sum of 216 quails were used. The quails were divided into three experimental groups during the 5 weeks of age based on their body weight: high body mass (HBM), >310 g, medium body mass (MBM) from 290 to 310 g, and low body mass (LBM), <290 g; and then transferred to egg-laying cages. There were three replicates per group. Internal and external egg quality traits, hatching traits, and egg-laying performance were examined. Main results: Egg production was statistically highest in the MBM group and the lowest in the HBM group (p≤0.05). The HBM group had the highest average egg weight and the lowest egg weight was observed in the LBM group (p≤0.05). The Haugh unit, albumen pH, shell thickness, yolk colour traits, shape index, albumen index, hatchability of fertile eggs, and yolk index were not statistically different among the experimental groups (p≥0.05). The fertility and hatchability of set eggs were statistically highest in the LBM group and lowest in the in the HBM group (p≤0.05). Research highlights: Selection for HBM could improve egg weight, however; it may have a negative correlation with egg production and hatching traits.

Effects of naked neck and frizzle genes on growth and egg-laying performance of chickens in the tropics in an era of climate change.

In regions characterized by tropical and subtropical climates, the elevated ambient temperatures exert adverse effects on both broiler and laying chickens, impacting their growth and egg production performance. To mitigate the challenges posed by heat stress, genetic strategies aimed at reducing feather coverage have gained prominence in hot climate areas. Among these approaches, the naked neck (Na) and frizzle (F) genes have emerged as particularly noteworthy. The Na and F genes play a pivotal role in facilitating heat dissipation and temperature regulation. By decreasing feather insulation, these genes enable efficient heat dissipation through exposed areas of the chickens' bodies. This reduction in feather coverage leads to elevated body surface temperature, which, in turn, enhances the capacity for heat loss and contributes to overall body temperature reduction. A substantial body of literature underscores the well-established positive impacts of the naked neck and frizzle genes on growth and egg-laying performance. As a result, these genes hold significant potential for integration into broiler and layer production systems, especially in regions characterized by high tropical temperatures. In the context of broiler farming under challenging heat conditions, the Na and F genes have demonstrated favorable effects on crucial parameters such as feed conversion ratio, body weight gain, disease resistance, and carcass attributes. Likewise, layers exposed to elevated temperatures exhibit enhanced egg production, eggshell quality, fertility, hatchability, and resistance to diseases when these genesare incorporated. Given that the prevalence of the naked neck and frizzle genes is primarily observed in indigenous chicken populations, it becomes imperative to prioritize measures for their conservation due to their exceptional performance in heat-stressed environments. To unlock the full genetic potential of exotic poultry reared in hot and humid conditions, the integration of the Na and F genes is a strongly recommended strategy.

Characterization of probiotic Bacillus sp. NP5 metabolites and its effect on female catfish broodstock rematuration

Probiotics are believed to contain active components that affect fish reproduction. This study aimed to evaluate the metabolite compounds contained in the probiotic Bacillus sp. NP5 and its effect on female catfish broodstock rematuration. The first step was to analyze the metabolite content of probiotic using liquid chromatography with tandem mass spectrometry LCMS/MS. Furthermore, feed supplementation was implemented with probiotic at concentrations of 106 CFU g-1 (P6), 108 CFU g-1 (P8), and control (C). Parameters observed included metabolite content of Bacillus sp. NP5, gonadosomatic index (GSI), hepatosomatic index (HSI), gonad histology, gonad maturity rate, fecundity, number of matured eggs, distribution of egg diameter, fertilization rate (FR), hatching rate (HR), larval survival (SR), rematuration period, and percentage of matured broodstock. The results showed that metabolites such as resveratrol (22.45%) and indoline (7.11%) are probably directly affecting reproduction. Other metabolites such as oxyresveratrol (22.95%) and vestitol (4.14%) are also thought to play an indirect role. Supplementation results showed the best reproductive performance in 108 CFU g-1 feed treatment with an increase in GSI (14.74%), HSI (1.65%), gonad maturity rate, percentage of mature eggs (86.00%), rematuration period (4 weeks), percentage of matured broodstock (100%), fecundity (243605.02 eggs/broodstock), FR (98.74%), HR (80.62%), and SR (87.31%). Application of probiotic Bacillus sp. NP5 can accelerate rematuration and improve reproductive performance of female catfish broodstock. Probiotics contain metabolites that have a positive effect on reproduction and can be an alternative in improving reproductive performance in female catfish broodstock. Keywords: Bacillus sp. NP5, female catfish, metabolites, probiotics, rematuration

Relationship between the timing of embryonic and larval development of pink salmon and downstream migration of its juveniles

Purpose: Determine the relationship between the duration of embryonic and larval development of pink salmon (Oncorhynchus gorbuscha) under different temperature regimes and the timing of downstream migration of their juveniles. Research Material: Multiyear average daily data on water temperature and condition of pink salmon embryos and larvae bred in commercial volumes at the Kurilsky (Iturup Island), Lesnoy and Pugachevsky (Eastern Sakhalin) salmon hatcheries. Methods used: Comparative data analysis, descriptive statistics methods.Results: The known facts about changes in the timing of embryonic development in relation to water temperature were confirmed: The duration of the interval between the dates of hatching of embryos in the first and last batches developed under different thermal conditions was 2.5 times longer than the interval between the dates of fertilization of eggs from these batches. The extension of the embryonic development period in the last batches was accompanied by a shortening of the subsequent development period until the fry were ready to swim, which reduced the difference in the duration of development from egg fertilization to fry swimming at different temperatures. This process is not only associated with different hatching times and slowed development in the winter period. The identified peculiarities in the changes in the duration of intermediate developmental stages under different temperature regimes suggest that fry developing in colder water goes afloat as less developed. Such regulation of the total duration of embryonic and larval development of pink salmon provides mass migration of its juveniles from rivers in the average annual terms of mass development of zooplankton in the coastal sea. Practical Significance: The presented article is a scientific accompaniment of the monitoring of pink salmon juvenile downstream migration in order to forecast changes in the stocks of this species of Pacific salmon.

MiR-92a-3p regulates egg fertilization through ribogenesis in the invasive fall armyworm Spodoptera frugiperda.

Understanding the epigenetic molecular mechanisms (EMMs) of reproduction is crucial for developing advanced and targeted control strategies for Spodoptera frugiperda. Differential expression analysis revealed 11 known miRNAs with varying expression levels, including nine upregulated and two downregulated miRNAs, in virgin females compared with males. The predictive analysis identified 426 target genes for these miRNAs, with ribogenesis highlighted as a key process in oogenesis and egg fertilization. This study also investigated the expression of miRNAs in both virgin and mated male and female S. frugiperda, with a focus on their roles in reproduction. A strong negative correlation was observed between miRNA expression levels and their target hub genes, confirming the transcriptional regulation by miRNAs. Additionally, protein-protein interaction (PPI) network identified the gene CG5033 (BOP1), as a central hub, was also predicted to be the target of miR-92a-3p in S. frugiperda, is involved in the maturation of large ribosomal RNA subunits. This study further provided experimental evidence that either the depletion of miR-92a-3p in virgin females or the knockdown of BOP1 in virgin males led to the production of infertile eggs post-mating. These findings validate the regulatory role of the miR-92a-3p - BOP1 interaction and underscore its importance in oogenesis and fertilization.

Copulation interruption decreases female reproductive success in a false widow spider

Copulation is essential for transferring sperm from males to females in most animals. During copulation, males and females are often static and thus prone to predation or other threats. Its duration should therefore be reduced to minimize costs but sufficient to ensure the fertilization of eggs. Here, we investigated reproductive behavior and success in the false widow spider, Steatoda grossa (Araneae: Theridiidae), when copulation was interrupted after 1, 3, 5, 10, or 20 min or was not experimentally interrupted (control). Copulation duration in this study is defined as the total duration of insertions of male pedipalps into a female’s copulatory openings. In S. grossa, uninterrupted copulations typically last 40 to 60 min. We found that within the first 5 min, copulation interruption negatively affected reproductive success (i.e., number of egg sacs, their total mass, and number of spiderlings), and delayed production of the first egg sac within the first 10 min (in some extreme instances by over 200 days). However, when copulation duration was 10 min or longer, reproductive outcome was unaffected. In the 1-min treatment, the number of egg sacs and their mass varied greatly, which indicates considerable variation among males with respect to the speed and efficiency of sperm transfer. We discuss the costs and benefits of extended copulation duration on female reproduction and on male and female fitness.

Success Rates of Assisted Reproduction for Men With Cystic Fibrosis.

The vast majority of men with CF (mwCF) are infertile. Improvements in assisted reproductive technology (ART) have made it possible for these patients to become biological fathers. Data were examined for all male CF patients attending a large adult CF center over a 23-year period. Azoospermia was confirmed via laboratory analysis of semen and was defined as complete absence of sperm in the ejaculate. Outcome of surgical sperm retrieval (SSR) procedure, post SSR complications, success rate of intracytoplasmic sperm injection (ICSI) and embryo transfer and subsequent live births were evaluated. Seventy-one mwCF with proven azoospermia were referred to fertility services over the study period. Mean (SD) percentage predicted forced expiratory volume in 1 second (ppFEV1) 67.86 ( ± 25.3), body mass index (BMI) 24.3 ( ± 3.7) kg/m2. Seventy (98.5%) of these men underwent and had successful SSR. 67/71 (94%) couples proceeded to have ICSI post SSR. 11 couples had failed egg fertilisation, implantation, or early miscarriage. 56/67 couples (84%) went on to have live births. To date 10/71 (14%) mwCF referred for fertility treatment have died. Mean ppFEV1 and BMI of mwCF who survived was higher than those who died; FEV1 72.8% ( ± 23.4) versus 38% ( ± 12.0) (p < 0.001), BMI 25.0 ( ± 3.5) kg/m2 versus 20.3 ( ± 2.2) kg/mg2 (p < 0.001). This is the largest study to investigate success rate of fertility treatment in mwCF and demonstrates that fertility treatment is successful in greater than 75% of patients referred. Clinical status and prognosis remain important factors when considering referral to fertility services.

Performance of egg production, fertility and hatchability of turkey in different production systems

Turkey (Meleagris gallopavo) is a popular poultry species which is able to adopt wide range of climatic condition and called by charismas chicken. A study was conducted in Swine and Avian Research Program, Khumaltar, Lalitpur to evaluate the egg production, fertility and hatchability of turkey in intensive and semi-intensive production system. This study was carried out from April 2019 to July 2020 that included 80 female and 16 male breeding turkeys. Among them 40 female and 8 male were kept under each system. In semi-intensive system turkeys started to lay eggs within 41 weeks and 10 % eggs production was received in 45 weeks whereas in intensive system one week more time was taken in both aspects. The hatchability in semi-intensive system was found 79.33±6.13 % whereas 43.09±9.70 % in case of intensive system. In case of fertility, in semi-intensive system it was found 84.77±2.98% and 53.68±5.40 % in intensive system. The eggs production was also much more different in both systems. In semi-intensive system, it was found 36.89±15.78 % and only 31.90±12.45% in intensive system. In the main breeding season from February to July per bird produced only 67 eggs in semi-intensive system and 58 in intensive system. The factors such as production system and months were significantly influenced (P&lt;0.001) in all productive traits. In both system, egg production and hatchability was more in April, May and June so this three month called peak egg production in Turkey. The hatchability of Turkey reared under semi-intensive system was much better which might be due to their grazing habit which helped to decrease aggressiveness of turkeys and did not disturb during matting time. Similarly, the wound in back of female turkey was less in semi-intensive system.Therefore semi-intensive production system is better in turkey for egg production, fertility and hatchability.

Enhancing In-Vitro Fertilization Outcomes through Machine Learning: A Comparative Analysis of Predictive Models and Dataset Evaluation

By enabling the fertilisation of eggs and sperm outside the body, in-vitro fertilisation (IVF) offers couples struggling with infertility hope through a complex medical procedure. The complex procedure involves causing the ovaries to release eggs, extracting the eggs, fertilising them with sperm in a lab environment to create embryos, and then putting the embryos into the uterus.Machine learning methodologies such as K-nearest neighbors (KNN), random forest, and support vector machine (SVM) exhibit potential in forecasting IVF outcomes and alleviating the physical and emotional burden associated with treatment. This study's objective was to examine several machine learning algorithms and assess the IVF dataset's reliability by contrasting it with other datasets. Consequently, the KNN model achieved a 64% accuracy rate, whereas the SVM, random forest, and logistic regression models obtained perfect accuracy rates of 100%. Assessing the IVF dataset using standardized data models through benchmarking helps confirm its quality, relevance, and importance, thus guiding efforts to improve IVF success rates. In essence, machine learning models are quite good at predicting the outcomes of IVF, which leads to customised reproductive therapies that improve IVF success.

Trehalose and Dimethyl Sulfoxide As Cryoprotective Solution Inclusions in a Static Liquid Nitrogen Vapour Vitrification Method for African Catfish (Clarias gariepinus Burchell, 1822) Sperm

Captive breeding of Clarias gariepinus (Burchell, 1822) entails stripping of mature females, while males must be killed or testes partially excised to obtain spermatozoa. Cryopreservation could significantly improve the reproductive potential of male catfish. In this study, Ginzburg fish Ringer (GFR) was the common extender in all protocols with or without 0.3 M trehalose. Dimethyl sulfoxide (DMSO) and methanol were tested to determine the preferred equilibration period for the complex before cryofreezing. The cryopreservation method and sperm fertilisation capacity were assessed in terms of hatchability rate. A feasible semen rationing protocol for maximised fertilisation was also evaluated. Semen equilibration with cryoprotectants was allowed for 30 minutes at 4 °C. Liquid nitrogen (LN2) vapour-induced freezing rates ranged from -2.7 to -5 °C.min⁻¹, and cryovials/straws were immersed in LN2 when -41 °C was reached after 12 min. Straws showed significantly improved cryopreservation efficacy over cryovials in terms of fertilisation. Optimal fertilisation occurred with trehalose and DMSO-treated cryostored sperm, comparable to fresh semen. Only 0.05 mL diluted semen was required to fertilise 35g eggs, compared with a similar volume efficacy for undiluted sperm. Trehalose enhanced egg fertilisation for both diluted fresh sperm and DMSO-treated thawed sperm. All methods produced healthy larvae to 21 days post-hatch. The validated method can yield 60 straws (0.5 mL) from 3 mL semen, fertilising approximately 2.1 kg eggs (~162 × 10⁴ eggs). The LN2 vapor vitrification method was shown to be both as effective as and more cost efficient than controlled rate freezing equipment.

In vitro evaluation of maize varieties on the development and reproduction of Chilo partellus (Lepidoptera: Crambidae)

In vitro experiments were conducted to evaluate the developmental and reproductive responses of Chilo partellus on different maize varieties in the Pesticide Toxicology and Application Technology Laboratory, Sindh Agriculture University, Tandojam. The maize stem borer, C. partellus, is a highly destructive insect pest that severely affects both fodder and cultivated crops worldwide. Although pesticides provide limited control of early infestations, they are ineffective against internal feeders and pose environmental risks. In contrast, utilizing resistant maize cultivars offers a sustainable, ecologically safe, and socially acceptable pest management strategy. The study revealed significant differences in the survival rates and developmental durations of C. partellus between hybrid and conventional maize under laboratory conditions. On conventional maize, the total developmental period ranged from 46.22 to 69.34 days (mean: 57.78 ± 11.56 days), whereas on hybrid maize, it ranged from 26.87 to 40.99 days (mean: 33.93 ± 7.06 days). Each developmental stage was shorter on hybrid maize. Females survived longer than males on both maize varieties, but their lifespan was notably shorter on hybrid maize. Regarding reproductive traits, C. partellus showed higher mean fecundity on conventional maize (604 ± 104.67 eggs, range: 500.11-709.44) compared to hybrid maize (302 ± 95.06 eggs, range: 207.44-397.56). Egg fertility was also significantly higher on conventional maize (mean: 55.44 ± 1.81%) compared to hybrid maize (mean: 24.61 ± 1.77%). Statistical analysis confirmed significant differences in developmental durations and reproductive traits between the two maize varieties. These findings highlight the potential of hybrid maize as a resistant cultivar against C. partellus.

The Influence of Sperm Activation Methods and Oocyte Collection on the Reproductive Effects of Northern Pike (Esox lucius)

This study compared the quality of northern pike eggs collected using traditional methods (hand stripping) and pneumatic methods (air stripping). The effects of different activation solutions (0.4% NaCl, 0.8% NaCl, and hatchery water) on egg fertilization under controlled conditions were also investigated. After egg collection, the Pseudo-Gonado-Somatic Index (PGSI) was measured; the PGSI values in the samples obtained using the pneumatic method (13.8 ± 3.9%) were lower, but did not differ statistically from those obtained by hand stripping (16.5 ± 5.4%). The 0.4% NaCl solution proved to be the most effective for sperm activation, as assessed by the Computer-Assisted Sperm Analysis (CASA) system, compared to the 0.8% NaCl solution. The pneumatic method achieved a higher egg collection efficiency (93.7% occlusion) than the traditional method, with significant differences observed in groups activated with water. The average hatching percentage of larvae was 89.5% in groups using the pneumatic method, compared to 71.2% in the traditional groups, highlighting the advantages of this modern approach. The application of the pneumatic method and 0.4% NaCl for the artificial fertilization of northern pike resulted in higher fertilization and hatching rates compared to other techniques, making this method a promising option for the artificial reproduction of other fish species.

Fertility and hatchability of KUB chicken eggs results from artificial insemination using liquid semen with carrot juice supplementation

Fertility is the success of spermatozoa in fertilizing an egg cell, while hatchability is a number that shows an egg's high or low ability to hatch. This research aims to determine the fertility and hatchability of KUB chicken eggs that have been stored cold by adding carrot juice to the basic diluent Ringer Lactate Egg Yolk. There were 60 KUB chickens divided into two treatment groups, each comprising 30 KUB hens. The group of eggs resulting from artificial insemination used fresh semen with Ringer Lactate diluent (P0), and eggs resulting from artificial insemination used liquid semen, which had been stored for 2 days with carrot juice supplemented with RLKT diluent (P1). The parameters observed were fertility and egg hatchability. Data were analyzed using descriptive analysis. The results showed that spermatozoa fertility at P0 was 87.11% while P1 was 56.09%. While the average percentage of hatchability shows a PQ result of 75.69 while P2 is 93.91%, it can be concluded that the fertility of KUB chickens using fresh semen is better than using liquid semen, but the hatchability of KUB chicken eggs using liquid semen is better than that of fresh semen. Further research is needed on the success of using liquid semen in AI applications in KUB chickens.

A conserved fertilization complex bridges sperm and egg in vertebrates.

Fertilization, the basis for sexual reproduction, culminates in the binding and fusion of sperm and egg. Although several proteins are known to be crucial for this process in vertebrates, the molecular mechanisms remain poorly understood. Using an AlphaFold-Multimer screen, we identified the protein Tmem81 as part of a conserved trimeric sperm complex with the essential fertilization factors Izumo1 and Spaca6. We demonstrate that Tmem81 is essential for male fertility in zebrafish and mice. In line with trimer formation, we show that Izumo1, Spaca6, and Tmem81 interact in zebrafish sperm and that the human orthologs interact invitro. Notably, complex formation creates the binding site for the egg fertilization factor Bouncer in zebrafish. Together, our work presents a comprehensive model for fertilization across vertebrates, where a conserved sperm complex binds to divergent egg proteins-Bouncer in fish and JUNO in mammals-to mediate sperm-egg interaction.

Involvement of Metalloproteases in the Fertilization of the Ascidian Halocynthia roretzi.

We previously reported that five astacin-like metalloproteases with thrombospondin type-1 repeats (Tasts) located on the sperm surface are a promising candidate as the protease involved in sperm penetration of the vitelline coat (VC) during fertilization of the ascidian Ciona intestinalis type A (Phlebobranchia). However, whether such a protease is involved in the fertilization of other ascidians is unknown. Here, we investigated the effects of four metalloprotease inhibitors on the fertilization of the ascidian Halocynthia roretzi (Stolidobranchia). Three metalloprotease inhibitors, GM6001, TAPI-0, and TAPI-1, strongly inhibited fertilization at 33 and 11 μM, whereas TAPI-2 weakly inhibited fertilization at 33 μM. In contrast, GM6001NC (negative control) had no effect on fertilization at 100 μM. Furthermore, GM6001 had no inhibitory effect on the fertilization of VC-deprived eggs. The metalloprotease appears to function at the middle or late stage of fertilization. Ten Tast genes were identified in the H. roretzi genome database, among which four genes (HrTast1, HrTast2b, HrTast2c, and HrTast3c) possessed a single transmembrane domain in the N-terminal region. These four genes are transcribed in the testis and ovary, as revealed by RT-PCR. Anti-HrTast2c IgG raised against a peptide corresponding to the Zn-binding consensus sequence weakly inhibited fertilization at 0.5 mg/mL. These results led us to propose that sperm astacin-like metalloproteases may be involved in sperm penetration of the VC during H. roretzi fertilization.

Morphology and chronology of critical events for early‐life history survival of an old word killifish, Esmaeilius shirini (Teleostei: Aphaniidae): A conservation management approach

AbstractIn this study, the live cell imaging microscopy of an old word cyprinodontiform fish, the Shirini toothcarp Esmaeilius shirini during its embryogenesis, is described and illustrated for the first time through the detailed morphological description and chronology of the events of all developmental stages (from fertilization to hatching). External fertilization of transparent, spherical, sticky and macrolecithal eggs bearing adhesive filaments with an average diameter of 0.83–1 mm is the first step in the ontogenesis of E. shirini. Embryogenesis continued with a process of meroblastic cleavage (approximately 2 and half h post‐fertilization, hpf), formation of blastula (blastulation), gastrula (gastrulation), neurulation, somatogenesis, organ formation (organogenesis) and pre‐hatching. The development continued with hatching (a stage between the embryonic and larval periods) at approximately 131 haf (at 24 ± 1°C). The new larvae were about 3.9–5.8 mm in length with distinct fin rays and pigmentation on the head, body and fins. Basic data from this study can be used in forthcoming investigations on the reproduction processes, breeding, behaviour and conservation of E. shirini. Fish development comprises an integrated, ordered and well‐mapped sequence of early life‐history events controlled by intrinsic and extrinsic factors. Knowledge of fish developmental stages during embryogenesis/ontogeny is essential for a better understanding of their biology, breeding criteria, phylogenetic relationships, dietary requirements, conservation plans, environmental requirements and ecological preferences.

H9 Consensus Hemagglutinin Subunit Vaccine with Adjuvants Induces Robust Mucosal and Systemic Immune Responses in Mice by Intranasal Administration.

The H9N2 subtype avian influenza viruses mainly cause respiratory symptoms, reduce the egg production and fertility of poultry, and result in secondary infections, posing a great threat to the poultry industry and human health. Currently, all H9N2 avian influenza commercial vaccines are inactivated vaccines, which provide protection for immunized animals but cannot inhibit the spread of the virus and make it difficult to distinguish between the infected animals and vaccinated animals. In this study, a trimeric consensus H9 hemagglutinin (HA) subunit vaccine for the H9N2 subtype avian influenza virus based on a baculovirus expression system was first generated, and then the effects of three molecular adjuvants on the H9 HA subunit vaccine, Cholera toxin subunit B (CTB), flagellin, and granulocyte-macrophage colony-stimulating factor (GM-CSF) fused with H9 HA, and one synthetic compound, a polyinosinic-polycytidylic acid (PolyI:C) adjuvant, were evaluated in mice by intranasal administration. The results showed that these four adjuvants enhanced the immunogenicity of the H9 HA subunit vaccine for avian influenza viruses, and that GM-CSF and PolyI:C present better mucosal adjuvant activity for the H9 HA subunit vaccine. These results demonstrate that we have developed a potential universal H9 HA mucosal subunit vaccine with adjuvants in a baculovirus system that would be helpful for the prevention and control of H9N2 subtype avian influenza viruses.

Three-way crossed scallops between Argopecten irradians irradians, A. i. concentricus and A. purpuratus exhibit strong heterosis in growth, survival and temperature tolerance

Three-way crossed scallops between Argopecten irradians irradians, A. i. concentricus and A. purpuratus exhibit strong heterosis in growth, survival and temperature tolerance