Adult Viability Research Articles

The Productivity and Viability of Snake River Sockeye Salmon Hatchery Adults Released into Redfish Lake, Idaho

AbstractIn 1991, the Snake River Sockeye Salmon Captive Broodstock Program was initiated to prevent the extinction and preserve the genetic diversity of this evolutionarily significant unit protected by the Endangered Species Act. At the time of listing, the Redfish Lake Sockeye Salmon Oncorhynchus nerka population was considered functionally extinct. One of the recovery strategies entails the release of adults for volitional spawning in Redfish Lake, Idaho, for rebuilding of the natural population. In this paper, we describe the productivity metrics from this strategy. We evaluated eight spawn years to address three primary questions: (1) What metrics for eggs to smolts, smolts per female, and smolt‐to‐adult returns (SARs) result from recent adult releases? (2) How do these metrics compare with historical estimates for Redfish Lake and estimates for other Sockeye Salmon populations throughout the range? and (3) Does the current combination of smolts per female and SARs result in population replacement? Replacement was determined as two adult recruits per female assuming an even sex ratio. We found that the reintroduced adults, despite being derived from a multigenerational captive broodstock, were able to successfully spawn and produce offspring that migrated to the ocean and returned as adults. Smolt abundance, size, and age data suggest that the population is functioning below density dependence. However, increased smolt production did not translate into greater adult returns and this is likely due to out‐of‐basin factors. Productivity metrics were similar to those of the wild population in Redfish Lake during the 1950s and 1960s. However, both current and historic productivity estimates were near the low end of the range for other Sockeye Salmon populations and have not resulted in population replacement. Until freshwater and out‐of‐basin survival can be improved, our data suggest that adult releases will continue to be an important recovery strategy to prevent cohort collapse and to rebuild naturally spawning populations.

Development and reprotuction of Spodoptera eridania on natural hosts and artificial diet.

The development and reproductive potential of Spodoptera eridania (Stoll, 1782) (Lepidoptera, Noctuidae) was compared on natural and artificial diets. Its biology was determined under laboratory conditions, providing an artificial diet, leaves of white clover and the peach cultivar 'Chimarrita' and fruits and leaves of the apple cultivar 'Gala'. Larvae of S. eridania could not complete their biological cycle when fed on apple fruits or peach leaves. The artificial diet provided the shortest development time, with a cycle of 28.5±0.14 days from egg to adult and 37.3% total viability. Apple leaves led to a longer development time from egg to adult (62.8±1.22 days) and lower total viability (23%) and white clover provided the highest total viability (54.3%). The results showed that S. eridania can use white clover and apple leaves to develop normally in apple orchards. The reduction of food sources such as white clover used by the larvae results in infestation and damage to fruits from "test bites".

Probing the Function of Metazoan Histones with a Systematic Library of H3 and H4 Mutants

Replication-dependent histone genes often reside in tandemly arrayed gene clusters, hindering systematic loss-of-function analyses. Here, we used CRISPR/Cas9 and the attP/attB double-integration system to alter numbers and sequences of histone genes in their original genomic context in Drosophila melanogaster. As few as 8 copies of the histone gene unit supported embryo development and adult viability, whereas flies with 20 copies were indistinguishable from wild-types. By hierarchical assembly, 40 alanine-substitution mutations (covering all known modified residues in histones H3 and H4) were introduced and characterized. Mutations at multiple residues compromised viability, fertility, and DNA-damage responses. In particular, H4K16 was necessary for expression of male X-linked genes, male viability, and maintenance of ovarian germline stem cells, whereas H3K27 was essential for late embryogenesis. Simplified mosaic analysis showed that H3R26 is required for H3K27 trimethylation. We have developed a powerful strategy and valuable reagents to systematically probe histone functions in D.melanogaster.

BACTERIA PRESENT IN SCARLET IBIS (Eudocimus ruber) CHICKS, BABITONGA BAY, SANTA CATARINA STATE, BRAZIL

Abstract Wild birds are important for public health because of their potential to transmit pathogenic microorganisms to humans. The waterbird scarlet ibis (Eudocimus ruber) forages and breeds near urban areas and if they settle near polluted waters, the viability of adults and their young can be negatively affected. Hence, the aim of this study was to evaluate the cloacal aerobic bacteria profile of nestling scarlet ibis in a mixed colony in Jarivatuba Island, in Joinville, Santa Catarina, Brazil. Cloacal swab samples were collected from clinically normal scarlet ibis nestlings during the breeding season of 2015/2016 (n=16) and 2016/2017 (n=34), and plated onto blood, MacConkey, and Salmonella-Shigella agar plates. Escherichia coli, Proteus vulgaris, Proteus spp., Klebsiella sp., Enterococcus spp. and Staphylococcus spp. were isolated and may be representative of the normal microbiota of E. ruber, although the normal profile is unknown for the species. However, the location of this colony in an area without adequate sewage treatment, which receives domestic effluents, may indicate a modified bacterial profile. Further studies are needed, to better understand the host's natural microbiome, as well as on the bacterial isolates, in order to characterize any association with the contaminated water. These results lay the foundation for successful species conservation projects in the area by providing insights that will help improve the viability of nestlings in each reproductive season.

BACTÉRIAS PRESENTES EM FILHOTES DE GUARÁ (Eudocimus ruber), BAÍA BABITONGA, ESTADO DE SANTA CATARINA, BRASIL

Wild birds are important for public health because of their potential to transmit pathogenic microorganisms to humans. The waterbird scarlet ibis (Eudocimus ruber) forages and breeds near urban areas and if they settle near polluted waters, the viability of adults and their young can be negatively affected. Hence, the aim of this study was to evaluate the cloacal aerobic bacteria profile of nestling scarlet ibis in a mixed colony in Jarivatuba Island, in Joinville, Santa Catarina, Brazil. Cloacal swab samples were collected from clinically normal scarlet ibis nestlings during the breeding season of 2015/2016 (n=16) and 2016/2017 (n=34), and plated onto blood, MacConkey, and Salmonella-Shigella agar plates. Escherichia coli, Proteus vulgaris, Proteus spp., Klebsiella sp., Enterococcus spp. and Staphylococcus spp. were isolated and may be representative of the normal microbiota of E. ruber, although the normal profile is unknown for the species. However, the location of this colony in an area without adequate sewage treatment, which receives domestic effluents, may indicate a modified bacterial profile. Further studies are needed, to better understand the host's natural microbiome, as well as on the bacterial isolates, in order to characterize any association with the contaminated water. These results lay the foundation for successful species conservation projects in the area by providing insights that will help improve the viability of nestlings in each reproductive season. Keywords: Pelecaniformes, scarlet ibis, nestlings, bacteria.

Filaricidal properties of Lantana camara and Tamarindus indica extracts, and Lantadene A from L. camara against Onchocerca ochengi and Loa loa.

BackgroundIvermectin is the only drug currently recommended for the treatment of onchocerciasis, the second leading infectious cause of blindness in the world. This drug kills only the first stage larvae—microfilariae (mf) of Onchocerca volvulus and is to be used cautiously in areas where Loa loa is prevalent because of severe adverse events observed with coinfected patients.Methodology/Principal findingsThis study investigated the anti-filarial activities of two Cameroonian medicinal plants, Lantana camara and Tamarindus indica locally used to treat onchocerciasis. Twelve (12) extracts were prepared and tested in vitro on the bovine model parasite, O. ochengi as well as L. loa mf. Both mf and adult male worm viabilities were assessed by motility scoring, while adult female worm viability was determined biochemically by standard MTT/formazan colorimetry. Cytotoxicity and acute toxicity were determined respectively, in monkey kidney epithelial cells and in BALB/c mice. Pure compounds were isolated by LC/MS using a bio-assay guided strategy. All the extracts showed 100% activity at 500 μg/mL against O. ochengi adult worms and mf. The highest activity against O. ochengi was observed with the hexane extract of L. camara leaves (LCLhex), with IC50 of 35.1 μg/mL for adult females and 3.8 μg/mL for the mf. Interestingly, this extract was more active against O. ochengi mf than L. loa mf. Further studies on the extracts led to the isolation of lantadene A from the methylene chloride extract of L. camara leaves, with IC50s of 7.85 μg/mL for adult males, 10.38 μg/mL for adult females, 10.84 μg/mL for O. ochengi mf and 20.13 μg/mL for L. loa mf.Conclusions/SignificanceWe report for the first time the anti-onchocercal activities of these locally consumed medicinal plants and lantadene A, a potential lead for further development as an onchocerciasis cure.

Viability selection by invertebrate predators in the polyphenic black scavenger fly Sepsis thoracica

Predation is a major factor influencing the fitness and life history of animals. Two key traits affecting prey survival are body size and coloration. Sepsis thoracica males display a sigmoid relationship between these 2 traits, defining a size threshold above which investment in melanin drastically drops, producing small melanic (black) or large amber morphs. In trying to understand the evolution of this rare dimorphism, we performed laboratory predation experiments to estimate the intensity of adult viability selection exerted by various arthropod predators (bugs, flies, and spiders) on male body size and coloration. Selection was performed against 2 different backgrounds mimicking the natural habitat (dung and grass) in which the camouflage and/or warning effect of the morphs should vary. Body size was mainly under positive selection (larger survived better), which overpowered selection on coloration and varied somewhat among predator species but not backgrounds. No disruptive selection was found, nor did selection change the sigmoid relationship between the 2 traits. We conclude that, for this fly, predator evasion and escaping skills determined by body size are more effective against invertebrate predators than its conspicuousness determined by coloration, contrasting what has been found for vertebrate predators, where prey coloration is important and negative selection on size dominates. Because arthropod predators have strong effects on insect populations, the positive directional selection imposed by invertebrate predators is likely an important force driving the evolution of body size in S. thoracica and insects in general.

Probing the Function of Metazoan Histones with a Systematic Library of H3 and H4 Mutants

Replication-dependent histone genes often reside in tandemly arrayed gene clusters, hindering systematic loss-of function analyses. Here we used CRISPR/Cas9 and the attP/attB double-integration system to alter the numbers and sequences of the histone genes in their original genomic context in Drosophila. As few as 8 copies of histone gene suffices to support embryo development and adult viability, whereas flies with 20 copies are indistinguishable from WT flies. Using a hierarchical assembly method, 40 alanine substitution mutations, covering all known modified residues on histone H3 and H4, were introduced and characterized. Mutations at multiple residues compromise viability, fertility, and DNA damage responses. In particular, H4K16 is necessary for expression of male X-linked genes, male viability and maintenance of ovarian germline stem cells, whereas H3K27 is essential for late embryogenesis. Finally, using simplified mosaic analysis, we found that H3R26 is required for H3K27 trimethylation. Taken together, we have developed a powerful strategy and valuable reagents for systematically probing histone functions in the fly.

Discovery by organism based high-throughput screening of new multi-stage compounds affecting Schistosoma mansoni viability, egg formation and production.

Schistosomiasis, one of the most prevalent neglected parasitic diseases affecting humans and animals, is caused by the Platyhelminthes of the genus Schistosoma. Schistosomes are the only trematodes to have evolved sexual dimorphism and the constant pairing with a male is essential for the sexual maturation of the female. Pairing is required for the full development of the two major female organs, ovary and vitellarium that are involved in the production of different cell types such as oocytes and vitellocytes, which represent the core elements of the whole egg machinery. Sexually mature females can produce a large number of eggs each day. Due to the importance of egg production for both life cycle and pathogenesis, there is significant interest in the search for new strategies and compounds not only affecting parasite viability but also egg production. Here we use a recently developed high-throughput organism-based approach, based on ATP quantitation in the schistosomula larval stage of Schistosoma mansoni for the screening of a large compound library, and describe a pharmacophore-based drug selection approach and phenotypic analyses to identify novel multi-stage schistosomicidal compounds. Interestingly, worm pairs treated with seven of the eight compounds identified show a phenotype characterized by defects in eggshell assemblage within the ootype and egg formation with degenerated oocytes and vitelline cells engulfment in the uterus and/or oviduct. We describe promising new molecules that not only impair the schistosomula larval stage but also impact juvenile and adult worm viability and egg formation and production in vitro.

Antifilarial activity of caffeic acid phenethyl ester on Brugia pahangi in vitro and in vivo

Lymphatic filariasis (LF) is a vector borne disease caused by parasitic worms such as Wuchereria bancrofti, Brugia malayi and B. timori, which are transmitted by mosquitoes. Current therapeutics to treat LF are mainly microfilarcidal, and lack activity against adult worms. This set back, poses a challenge for the control and elimination of filariasis. Thus, in this study the activities of caffeic acid phenethyl ester (CAPE) against the filarial worm B. pahangi and its bacterial endosymbiont, Wolbachia were evaluated. Different concentrations (2, 5, 10, 15, 20 μg/ml) of CAPE were used to assess its effects on motility, viability and microfilarial (mf) production of B. pahangi in vitro. Anti-Wolbachial activity of CAPE was measured in worms by quantification of Wolbachial wsp gene copy number using real-time polymerase chain reaction. Our findings show that CAPE was found to significantly reduce adult worm motility, viability, and mf release both in vitro and in vivo. 20 μg/ml of CAPE halts the release of mf in vitro by day 6 of post treatment. Also, the number of adult worms recovered in vivo were reduced significantly during and after treatment with 50 mg/kg of CAPE relative to control drugs, diethylcarbamazine and doxycycline. Real time PCR based on the Wolbachia ftsZ gene revealed a significant reduction in Wolbachia copy number upon treatment. Anti-Wolbachia and antifilarial properties of CAPE require further investigation as an alternative strategy to treat LF.

Arsenic trioxide exposure impairs testicular morphology in adult male mice and consequent fetus viability

ABSTRACTThe acute promyelocytic leukemia (APL) is a rare disease, affecting 0.1/100,000 individuals globally. Despite significant advances in APL therapy, some patients still experience relapsed disease. Currently, arsenic trioxide (As2O3) was found to be effective in relapsed APL treatment and considered as standard treatment for these cases. However, it has been shown that exposure to As2O3 may exert adverse effects on the male reproductive system since this substance might also induce apoptosis of other important cell types including stem cells. Studies demonstrated that treatment with this metallic substance decreased plasma levels of testosterone and interfered with sperm parameters such as concentration, motility, and viability. In addition, As2O3 was found to produce significant damage to spermatocytes, which may be associated with testicular toxicity and consequent inhibition of spermatogenesis. The aim of this study was to determine sub-chronic treatment effects of As2O3 on sperm and testicular morphology, androgen receptor (AR) immunoreactivity in testes and epididymis, in addition to evaluation of fertility parameters in adult male mice. Thirty adult Swiss mice were divided into three experimental groups: control; received distilled water (vehicle) while treated received 0.3 or 3 mg/kg/day As2O3 subcutaneously, for 5 days per week, followed by 2 days of interruption, for 5 weeks. Results showed that As2O3 (1) decreased spermatozoa number, (2) produced seminiferous epithelium degeneration and exfoliation of germ cells tubule lumen (3) altered nucleus/cytoplasm proportion of Leydig cells and (4) reduced AR immunoreactivity in both Leydig and epithelial epididymal cells. Further, fetal viability tests demonstrated an increase in post-implantation loss in females that were mated with As2O3-treated males. Data indicate that As2O3 exposure altered the spermatogenic process and subsequently fetal viability.

Transgenerational effects of maternal and grandmaternal age on offspring viability and performance in Drosophila melanogaster

In non-social insects, fitness is determined by relative lifetime fertility. Fertility generally declines with age as a part of senescence. For females, senescence has profound effects on fitness by decreasing viability and fertility as well as those of her offspring. However, important aspects of these maternal effects, including the cause(s) of reduced offspring performance and carry-over effects of maternal age, are poorly understood. Drosophila melanogaster is a useful system for examining potential transgenerational effects of increasing maternal age, because of their use as a model system for studying the physiology and genetic architecture of both reproduction and senescence. To test the hypothesis that female senescence has transgenerational effects on offspring viability and development, we measured the effects of maternal age on offspring survival over two generations and under two larval densities in two laboratory strains of flies (Oregon-R and Canton-S). Transgenerational effects of maternal age influence embryonic viability and embryonic to adult viability in both strains. However, the generation causing the effects, and the magnitude and direction of those effects differed by genotype. The effects of maternal age on embryonic to adult viability when larvae are stressed was also genotype-specific. Maternal effects involve provisioning: older females produced smaller eggs and larger offspring. These results show that maternal age has profound, complex, and multigenerational consequences on several components of offspring fitness and traits. This study contributes to a body of work demonstrating that female age is an important condition affecting phenotypic variation and viability across multiple generations.

Effects of ovarian disaggregation on adult murine follicle yield and viability.

Follicles are isolated from ovaries for numerous reasons, including IVM, but adult murine yields are <2 folliclesmg-1. The aim of the present study was to optimise ovarian disaggregation and develop methods applicable to the rapid screening of follicle viability. Ovaries from adult mice (n=7) were halved and disaggregated mechanically, or by using collagenase IV (Col-IV; 590UmL-1) or animal origin-free collagenase IV (AOF) at 590 or 1180UmL-1. Isolated follicles were stained with 4',6'-diamidino-2-phenylindole (DAPI; nuclei), chloromethyl-X-rosamine (CMXRos; mitochondria) or fluorescein isothiocyanate-conjugated anti-α-tubulin antibody. Follicle diameters and staining were measured and analysed using ImageJ, and data analysed using GraphPad Prism. Col-IV disaggregation yielded the highest number of follicles (17±10 folliclesmg-1 ovarian tissue). All disaggregation methods released more secondary follicles (86±20 per ovary; P<0.05) than any other size cohort. Mechanical and Col-IV disaggregation yielded similar numbers of morphologically intact follicles, whereas AOF disaggregation caused more damage (P<0.01). As the morphological disruption increased, DAPI and CMXRos staining decreased (P<0.05), and tubulin localisation became more heterogeneous. Col-IV disaggregation gave the best yield of morphologically intact follicles containing viable granulosa cells. In conclusion, we improved adult murine follicle yields and applied molecular markers to assess follicle morphology, cellular cytoskeleton and mitochondrial function.

The GATOR1 Complex Regulates Metabolic Homeostasis and the Response to Nutrient Stress in Drosophila melanogaster.

TORC1 regulates metabolism and growth in response to a large array of upstream inputs. The evolutionarily conserved trimeric GATOR1 complex inhibits TORC1 activity in response to amino acid limitation. In humans, the GATOR1 complex has been implicated in a wide array of pathologies including cancer and hereditary forms of epilepsy. However, the precise role of GATOR1 in animal physiology remains largely undefined. Here, we characterize null mutants of the GATOR1 components nprl2, nprl3, and iml1 in Drosophila melanogaster. We demonstrate that all three mutants have inappropriately high baseline levels of TORC1 activity and decreased adult viability. Consistent with increased TORC1 activity, GATOR1 mutants exhibit a cell autonomous increase in cell growth. Notably, escaper nprl2 and nprl3 mutant adults have a profound locomotion defect. In line with a nonautonomous role in the regulation of systemic metabolism, expressing the Nprl3 protein in the fat body, a nutrient storage organ, and hemocytes but not muscles and neurons rescues the motility of nprl3 mutants. Finally, we show that nprl2 and nprl3 mutants fail to activate autophagy in response to amino acid limitation and are extremely sensitive to both amino acid and complete starvation. Thus, in Drosophila, in addition to maintaining baseline levels of TORC1 activity, the GATOR1 complex has retained a critical role in the response to nutrient stress. In summary, the TORC1 inhibitor GATOR1 contributes to multiple aspects of the development and physiology of Drosophila.

Effects of temperature and nonionizing ultraviolet radiation treatments of eggs of five host insects on production of Trichogramma chilonis Ishii (Hymenoptera: Trichogrammatidae) for biological control applications

Trichogramma species are used worldwide as biological control agents. A particularly important application is mass-rearing and release for management of field-crop and warehouse insect pests. Eggs of commonly available hosts, Spodoptera litura, Corcyra cephalonica, Plutella xylostella and Helicoverpa armigera, were exposed to different temperature and nonionizing ultraviolet (UV) radiation treatments to consider whether particular combinations of treatments positively affected T. chilonis development. The treatments had different effects on three measures of parasitoid production: the rate of parasitization, adult emergence, and adult viability. At constant temperature (24, 28, 32°C), the mean percentage of egg parasitization was greatest on treatments of S. litura eggs. However, the mean percentage of adult emergence was significantly greater from C. cephalonica eggs at 28°C than from eggs in other treatments. The mean percentage of adult viability was found to be 83.9% from C. cephalonica eggs at 28°C. Ultraviolet radiation treatments (3, 6, or 9min at 254nm) significantly increased the mean percentage parasitization over that of the non-UV treatments. Also, the mean percentage of adult parasitoid emergence and viability were greater from C. cephalonica eggs exposed to non-ionizing UV radiation than from eggs of other hosts in all other treatments. This information can be used by managers of mass-rearing programs to increase the effectiveness of T. chilonis production for biological control of pest insects.

Is cell viability always directly related to corrosion resistance of stainless steels?

It has been frequently reported that cell viability on stainless steels is improved by increasing their corrosion resistance. The question that arises is whether human cell viability is always directly related to corrosion resistance in these biostable alloys. In this work, the microstructure and in vitro corrosion behavior of a new class of medical-grade stainless steels were correlated with adult human mesenchymal stem cell viability. The samples were produced by a powder metallurgy route, consisting of mechanical alloying and liquid-phase sintering with a sintering aid of a eutectic Mn–Si alloy at 1050°C for 30 and 60min, leading to nanostructures. In accordance with transmission electron microscopic studies, the additive particles for the sintering time of 30min were not completely melted. Electrochemical impedance spectroscopic experiments suggested the higher corrosion resistance for the sample sintered for 60min; however, a better cell viability on the surface of the less corrosion-resistant sample was unexpectedly found. This behavior is explained by considering the higher ion release rate of the Mn–Si additive material, as preferred sites to corrosion attack based on scanning electron microscopic observations, which is advantageous to the cells in vitro. In conclusion, cell viability is not always directly related to corrosion resistance in stainless steels. Typically, the introduction of biodegradable and biocompatible phases to biostable alloys, which are conventionally anticipated to be corrosion-resistant, can be advantageous to human cell responses similar to biodegradable metals.

An essential cell cycle regulation gene causes hybrid inviability in Drosophila.

Speciation, the process by which new biological species arise, involves the evolution of reproductive barriers, such as hybrid sterility or inviability between populations. However, identifying hybrid incompatibility genes remains a key obstacle in understanding the molecular basis of reproductive isolation. We devised a genomic screen, which identified a cell cycle-regulation gene as the cause of male inviability in hybrids resulting from a cross between Drosophila melanogaster and D. simulans. Ablation of the D. simulans allele of this gene is sufficient to rescue the adult viability of hybrid males. This dominantly acting cell cycle regulator causes mitotic arrest and, thereby, inviability of male hybrid larvae. Our genomic method provides a facile means to accelerate the identification of hybrid incompatibility genes in other model and nonmodel systems.

Breeding and Reproductive Phenology of Eastern Diamond-Backed Rattlesnakes (Crotalus adamanteus) in South Carolina

Abstract Phenology is an important dimension of vertebrate reproductive strategies. Characterizing a species' reproductive phenology is a fundamental step in directing studies of influences on reproduction within and among populations throughout its range. Eastern Diamond-Backed Rattlesnakes (Crotalus adamanteus; EDBs) are endemic predators of the imperiled longleaf pine (Pinus palustris) ecosystem of the southeastern United States, and the species currently is under review for listing under the Endangered Species Act. Conservation and management of this imperiled species will greatly benefit from research on its basic biology, and particularly from information that will assist management for adult survival and population viability. Here, we present long-term data on EDB breeding and reproductive phenology from several populations in the South Carolina Coastal Plain. We summarized the phenology of EDB breeding and reproduction using observations of free-ranging, radiotelemetered rattlesnakes in South Caro...

Differential Masking of Natural Genetic Variation by miR-9a in Drosophila.

Genetic variation is prevalent among individuals of the same species and yet the potential effects of genetic variation on developmental outcomes are frequently suppressed. Understanding the mechanisms that are responsible for this suppression is an important goal. Previously, we found that the microRNA miR-9a mitigates the impact of natural genetic variants that promote the development of scutellar bristles in adult Drosophila. Here we find that miR-9a does not affect the impact of genetic variants that inhibit the development of scutellar bristles. We show this using both directional and stabilizing selection in the laboratory. This specificity of action suggests that miR-9a does not interact with all functional classes of developmental genetic variants affecting sensory organ development. We also investigate the impact of miR-9a on a fitness trait, which is adult viability. At elevated physiological temperatures, miR-9a contributes to viability through masking genetic variants that hinder adult viability. We conclude that miR-9a activity in different developmental networks contributes to suppression of natural variants from perturbing development.

Mcm10 is required for oogenesis and early embryogenesis in Drosophila

Efficient replication of the genome and the establishment of endogenous chromatin states are processes that are essential to eukaryotic life. It is well documented that Mcm10 is intimately linked to both of these important biological processes; therefore, it is not surprising that Mcm10 is commonly misregulated in many human cancers. Most of the research regarding the biological roles of Mcm10 has been performed in single-cell or cell-free in-vitro systems. Though these systems are informative, they are unable to provide information on the cell-specific function of Mcm10 in the context of the tissue and organ systems that comprise multicellular eukaryotes. We therefore sought to identify the potential biological functions of Mcm10 in the context of a complex multicellular organism by continuing our analysis in Drosophila using three novel hypomorphic alleles. Observation of embryonic nuclear morphology and quantification of embryo hatch rates reveal that maternal loading of Mcm10 is required for embryonic nuclear stability, and suggest a role for Mcm10 post zygotic transition. Contrary to the essential nature of Mcm10 depicted in the literature, it does not appear to be required for adult viability in Drosophila if embryonic requirements are met. Although not required for adult somatic viability, analysis of fecundity and ovarian morphology in mutant females suggest that Mcm10 plays a role in maintenance of the female germline. Taken together, our results demonstrate critical roles for Mcm10 during early embryogenesis, and mark the first data linking Mcm10 to female specific reproduction in multicellular eukaryotes.