Eye Color Research Articles

Impact of iris color on uveal melanoma-related outcomes in 7245 patients at a single ocular oncology center

PurposeTo determine the relationship between iris color and uveal melanoma (UM)-related metastasis and death in a large cohort of patients from a single ocular oncology center. DesignRetrospective case series. SubjectsPatients diagnosed with UM between February 1971 and August 2007. MethodsPatient information was obtained from chart documentation. Main outcome measuresUM-related metastasis and death. ResultsOut of 7245 patients, iris color was blue in 3702 (51%), green in 1458 (20%), and brown in 2085 (29%). Mean age was 58 ± 15 years and mean tumor thickness was 5.5 ± 3.3 millimeters. Some clinical features differed between iris color groups, with the blue irides group having a larger proportion of post-equatorial tumors with significantly closer proximity to the foveola and optic disc compared to the brown irides group. At a mean follow-up of 75 months, there was no statistically significant difference in metastasis between the various iris color groups. On univariate analysis, those with blue irides showed a higher incidence of UM-related death compared to the green and brown irides groups (8.3%, 5.9% and 7.5% respectively, p value = 0.02). Kaplan-Meier event free survival from UM-related death significantly differed only between the blue and green irides groups (p value = 0.007) with the green irides group showing the highest survival. However, on multivariate analysis, iris color was not predictive of UM-related death. ConclusionIris color was not predictive of UM-related metastasis or death. However, Kaplan-Meier survival at 20 years was poorest for blue irides group compared to green.

Are dark-eyed dogs favoured by humans? Domestication as a potential driver of iris colour difference between dogs and wolves.

Comparative studies have shown that the eye morphology of primates has been shaped by a variety of selection pressures (e.g. communication, environmental factors). To comprehensively elucidate the complex links between ocular morphology and its evolutionary drive, attention should be paid to other phylogenetic groups. Here, we address a new question regarding the evolution of eye colour patterns in the oldest domesticated animal, namely, the domestic dog (Canis familiaris). In this study, we conducted an image analysis of dogs and their closest relatives, grey wolves (Canis lupus), to compare the colours of their irises, with the aim of assessing whether eye colours of dogs affect how humans perceived dogs. We found that the irises of dogs were significantly darker than those of wolves. We also found that facial images of dark-eyed dogs were perceived as more friendly and immature, potentially eliciting caregiving responses from humans. Our findings are consistent with our expectation that humans favour dark-eyed dogs over light-eyed ones and provide an updated hypothesis that dogs with dark eyes may have evolved by acquiring a facial trait that sends a non-threatening gaze signal to humans.

MTOR signaling pathway regulates embryonic development and rapid growth of triploid crucian carp

Triploid crucian carp is a new breed of aquaculture with rapid growth characteristics. However, its growth regulation mechanism has not yet been elucidated. In this study, our results show that the expression levels of mTOR signaling pathway-related genes (AKT1, AKT2, AKT3, mTOR, 4E-BP1 and S6K1) are higher in the muscle and intestine tissues of triploid crucian carp than those of diploid red crucian carp. Embryos of triploid crucian carp exhibit a faster growth rate comparing to red crucian carp. And in muscle effect stage, the mRNA levels of mTOR signaling pathway related genes in triploid crucian carp are higher than red crucian carp, except for AKT2. Inhibition of mTOR activity with rapamycin leads to slower embryonic development and the eliminated expression of mTOR in the embryos of neurula, muscle effect, and eye pigmentation stages. Conversely, overexpression of the upstream gene AKT2 can promote the development of zebrafish embryos and affect the expression of mTOR signaling pathway. These data highlight the significant role of mTOR signaling pathway in regulating fish embryonic development and rapid growth, and might offer new insights and avenues for exploring fish embryonic development, improving fish growth.

Identification of Fresh and Unfresh Fish Based on Eye Image Using The Self-Organizing Maps (SOM) Method

Fish is a common protein source and easy to obtain in Indonesia, but because of its high water content, fish quickly spoils. Fish freshness can be detected using several conventional methods, such as chemical analysis, biochemistry, microbiological analysis, and sensory examination. Another identification method involves observing the color of the fish's eyes. Fish identification is crucial before any further processing, ensuring that the fish's quality delivered to consumers remains high. To tackle the problem of differentiating between fresh and non-fresh fish, this research employs Self-Organizing Maps (SOM) as the primary methodology. This research focuses on identifying fresh and non-fresh fish using the SOM method, using actual data involving tilapia as the research object. The data includes eye images of new and non-fresh fish, and various procedures are required to obtain the desired data. This data is then used as training and testing data. The process continues with the preprocessing stage, which is a data modification process to improve performance in subsequent steps and feature extraction using HSV color histograms. Classification of processed data is carried out using the SOM method. Once completed, the identification results are displayed. This research produces a system for identifying fresh and non-fresh fish based on eye images using SOM, which achieves a good accuracy of 85.71%.

Characterization of intrapuparial development of Musca domestica (Diptera: Muscidae), under different temperatures in laboratory conditions.

Musca domestica (Linnaeus, 1758) (Diptera: Muscidae), popularly known as "housefly", is a highly synanthropic species, with economic, medical-sanitary, veterinary, and forensic importance. It is able to cause damage to health, transmit pathogenic agents, cause infection in domestic animals, and, in its immature stage, cause secondary myiasis. The scavenging habit of its immature stages makes these flies pioneers in colonizing both human and animal carcasses, from the initial stages of corpse decomposition to the final stages. Intrapuparial development studies of all stages of the biological cycle of these insects help estimate pupal age, being useful to forensic entomology to aid in determining the minimum postmortem interval (minPMI). This study describes, morphologically, the external structures of the pupae, under temperatures of 23, 27, and 30 ± 1 °C aiming to identify the characteristics that define their developmental stages and estimation of the pupae age of M. domestica. The whole experiment was carried out under laboratory conditions, with relative humidity 60 ± 10% and 12 hours of photoperiod. The process of pupariation and pupation including pre-pupae phases were observed; larvae pupae apolysis; early cryptocephalic pupae; late cryptocephalic pupae; phanerocephalic pupae; pharate adult, discriminated by eye color (transparent eyes, pink eyes, and red eyes); and the emergency of adults, which occurred in the intervals of 162-180; 138-144, and 96-102 hr, respectively, being described throughout the metamorphosis of the external morphological characteristics of the pupal stage of M. domestica.

Observations on the embryonic development of the mud crab, Scylla paramamosain

To investigate the embryonic development of the mud crab Scylla paramamosain, we analyzed three critical parameters: egg color of, embryo morphology (through conventional and laser scanning confocal microscopy), and the distribution of cell divisions. During embryonic development, the egg color exhibited a progressive transition, shifting from orange to reddish-orange, then to brown, before ultimately darkening to black. Each embryo displayed a spherical shape, measuring approximately 280 μm in diameter, characterized by a smooth surface devoid of any depressions. The embryonic cell division was in the form of mixed oogenesis, comprised of complete division in the early stage, spiral oogenesis in the middle stage and surface division in the late stage. It is noteworthy that the blastopore appeared at the position where the transparent area and cell aggregation just appeared under the microscope, and the blastomere was a characteristic of the embryo entering the gastrulation stage. After entering the gastrulation stage, the cells aggregated towards the blastopore and formed two symmetrical cell clusters, which formed a V-shape with the void of the classic blastopore. When the transparent region occupied approximately 1/5 of the embryo’s volume, the embryo entered the nauplius stage, and the thoracic and abdominal armor, as well as the optic lobe and abdominal limb primordia, could be clearly distinguished. The appearance of the compound eye pigment band indicated the stage of compound eye pigment formation. At this time, the transparent area accounted for 1/4 of the embryo and a large number of ganglia appeared. The change of the compound eye pigment band from red to black was also one of the reasons for the blackening of the egg color of the crabs. The data obtained through this study have potential applications in the determination of embryonic development status and obtaining of high-quality seeds for S. paramamosain culture.

The Sin, Evil, Ugliness and Horror of Blue: Blue Eyes in 14th-15th Century Divan Poetry

In Turkish poetic and prose works written during the 14th and 15th centuries, the blue eye color was synonymous with danger, hatred, repulsion and wickedness, both in this world and in the afterlife. According to some stories and texts, blue eyes, which the Turks accepted as sacred, chosen, and superior in pre-Islamic times, became associated with liars, sinners, terrifying, wicked, and ruthless people and beings in Turkish poetic and prose works written in and outside of Anatolia during the 14th and 15th centuries. This article traces the use of blue eyes in 14th and 15th century Divan poetry. First, the works that depict blueeyed wicked, terrifying, ruthless, ugly, and deceitful characters and beings are identified. Later, the reason behind this notable negative attitude towards blue eyes is explored and revealed by examining its origins.

CRISPR/Cas9-mediated mutagenesis of the white gene in an ectoparasitic wasp, Habrobracon hebetor.

The ectoparasitic wasp Habrobracon hebetor (Hymenoptera, Braconidae) can parasitize various species of lepidopteran pests. To maximize its potential for biological control, it is necessary to investigate its gene function through genome engineering. To test the effectiveness of genome engineering system in H. hebetor, we injected the mixture of clustered regularly interspaced short palindromic repeats (CRISPR) -associated (Cas) 9 protein and single guide RNA(s) targeting gene white into embryos. The resulting mutants display a phenotype of eye pigment loss. The phenotype was caused by small indel and is heritable. Then, we compared some biological parameters between wildtype and mutant, and found there were no significant differences in other parameters except for the offspring female rate and adult longevity. In addition, cocoons could be used to extract genomic DNA for genotype during the gene editing process without causing unnecessary harm to H. hebetor. Our results demonstrate that the CRISPR/Cas9 system can be used for H. hebetor genome editing and it does not adversely affect biological parameters of the parasitoid wasps. We also provide a feasible non-invasive genotype detection method using genomic DNA extracted from cocoons. Our study introduces a novel tool and method for studying gene function in H. hebetor, and may contribute to better application of H. hebetor in biocontrol. © 2023 Society of Chemical Industry.

Noninfectious Outcomes of Intravitreal Antibiotic Steroid Injection and Topical Nonsteroidal Antiinflammatory Drugs Versus Triple Drop Therapy After Cataract Surgery

To compare noninfectious outcomes of intravitreal antibiotic steroid (IVAS) injection (moxifloxacin-triamcinolone) and postoperative topical nonsteroidal antiinflammatory drugs (NSAID) with a standard 3-drop therapy (TDT) regimen (topical antibiotic, steroid, and NSAID) in patients after cataract surgery. Retrospective comparative clinical cohort study. In 3 study centers in the United States, a total of 2143 eyes (N = 2143 patients) underwent cataract surgery with IVAS-NSAID or TDT between 2017 and 2022. Preoperative data were included, including patients' age, iris color, medical history, and ocular history. Postoperative data, including best-corrected visual acuity, intraocular pressure (IOP), and the need for IOP-lowering medications, were recorded at 1-week, 1-month, and 6-month time points. The primary outcome measures were postoperative complications, defined as persistent anterior chamber inflammation, persistent corneal edema (PCE), rebound inflammation, and cystoid macular edema, were compared between the 2 groups. There were 1079 eyes in the IVAS-NSAID group and 1064 eyes in the TDT group. Best-corrected visual acuity and IOP were similar between IVAS-NSAID and TDT eyes at all time points. A portion (11.6%) of TDT eyes experienced postoperative complications compared with 6.5% in IVAS-NSAID eyes (P < .001). Femtosecond laser-assisted cataract surgery was associated with increased rates of PCE in IVAS-NSAID eyes, and eyes with dark irides had a higher incidence of cystoid macular edema, PCE, and rebound inflammation in the IVAS-NSAID group. The IVAS-NSAID regimen overall had similar postoperative outcomes and fewer complications compared with the TDT regimen. IVAS-NSAID may be considered a safe alternative to topical regimens in non-femtosecond laser-assisted cataract surgery and patients with light irides.

Epidemiology of geographic atrophy and its precursor features of intermediate age‐related macular degeneration

AbstractGlobally age‐related macular degeneration (AMD) is a leading cause of blindness with a significant impact on quality of life. Geographic atrophy (GA) is the atrophic late form of AMD and its prevalence increases markedly with age with around 1 in 5 persons aged 85 and above having GA in at least one eye. Bilateral GA leads to severe visual impairment thus posing a significant burden on patients, careers and health providers. The incidence and prevalence of GA varies across different geographic regions, with the highest rates in those of European ancestry. Although heterogeneity in definitions of GA and reporting strategy can explain some of the discrepancies, the data overall are consistent in showing a lower prevalence in other ethnicities such as those of Asian heritage. This is at present unexplained but thought to be due to the existence of protective factors such as differences in eye pigmentation, diet, environmental exposures and genetic variability. This review covers key aspects of the prevalence and incidence of the ocular precursor features of GA (large drusen, pigmentary abnormalities and reticular pseudo‐drusen), the late stage of GA and factors that have been known to be associated with modifying risk including systemic, demographic, environment, genetic and ocular. Understanding the global epidemiology scenario is crucial for the prevention of and management of patients with GA.

Eye and hair color prediction of human DNA recovered from Lucilia sericata larvae.

Forensic entomological evidence is employed to estimate minimum postmortem interval (PMImin), location, and identification of fly samples or human remains. Traditional forensic DNA analysis (i.e., STR, mitochondrial DNA) has been used for human identification from the larval gut contents. Forensic DNA phenotyping (FDP), predicting human appearance from DNA-based crime scene evidence, has become an established approach in forensic genetics in the past years. In this study, we aimed to recover human DNA from Lucilia sericata (Meigen 1826) (Diptera: Calliphoridae) gut contents and predict the eye and hair color of individuals using the HIrisPlex system. Lucilia sericata larvae and reference blood samples were collected from 30 human volunteers who were under maggot debridement therapy. The human DNA was extracted from the crop contents and quantified. HIrisPlex multiplex analysis was performed using the SNaPshot minisequencing procedure. The HIrisPlex online tool was used to assess the prediction of the eye and hair color of the larval and reference samples. We successfully genotyped 25 out of 30 larval samples, and the most SNP genotypes (87.13%) matched those of reference samples, though some alleles were dropped out, producing partial profiles. The prediction of the eye colors was accurate in 17 out of 25 larval samples, and only one sample was misclassified. Fourteen out of 25 larval samples were correctly predicted for hair color, and eight were misclassified. This study shows that SNP analysis of L. sericata gut contents can be used to predict eye and hair color of a corpse.

Jewish Genetic Diseases

What makes you, you? Your genes. Every human has a unique genetic code made of genes. Genes are the basic physical and functional unit of heredity and are made of DNA. Each gene ranges from a few hundred DNA bases to more than 2 million. A human being has between 20,000 to 25,000 genes. Each person inherits two copies of each gene, one copy from the mother and the other from the father. Most of our genes are the same; less than one percent of genes differ between people. These differing components are known as alleles. Alleles are forms of the same gene but with small differences in their DNA bases, and alleles are what make each one of us unique. One’s genotype is the internal, inherited genetic code inside all living organisms. A phenotype is the outside, physical manifestation of those genes. Phenotype examples include skin, eye, and hair color. They are related to all that is physical, functional, or behavioral [1,2].

Utilizing 3D Printing Technology to Create Prosthetic Irises: Proof of Concept and Workflow.

There are currently limited treatment options for aniridia. In this context, 3D printed iris implants may provide a cost-effective, cosmetically acceptable alternative for patients with aniridia. The purpose of this study was to develop a proof-of-concept workflow for manufacturing 3D printed iris implants using a silicone ink palette that aesthetically matches iris shades, identified in slit lamp images. Slit lamp iris photos from 11 healthy volunteers (3 green; 4 blue; 4 brown) were processed using k-means binning analyses to identify two or three prominent colors each. Candidate silicone inks were created by precisely combining pigments. A crowdsourcing survey software was used to determine color matches between the silicone ink swatches and three prominent iris color swatches in 2 qualifying and 11 experimental workflows. In total, 54 candidate silicone inks (20 brown; 16 green; 18 blue) were developed and analyzed. Survey answers from 29 individuals that had passed the qualifying workflow were invited to identify "best matches" between the prominent iris colors and the silicone inks. From this color-match data, brown, blue, and green prototype artificial irises were printed with the silicone ink that aesthetically matched the three prominent colors. The iris was printed using a simplified three-layer five-branch starburst design at scale (12.8 mm base disc, with 3.5 mm pupil). This proof-of-concept workflow produced color-matched silicone prosthetic irises at scale from a panel of silicone inks using prominent iris colors extracted from slit lamp images. Future work will include printing a more intricate iris crypt design and testing for biocompatibility.

Efficient DIPA-CRISPR-mediated knockout of an eye pigment gene in the white-backed planthopper, Sogatella furcifera.

Although CRISPR/Cas9 has been widely used in insect gene editing, the need for the microinjection of preblastoderm embryos can preclude the technique being used in insect species with eggs that are small, have hard shells, and/or are difficult to collect and maintain outside of their normal environment. Such is the case with Sogatella furcifera, the white-backed planthopper (WBPH), a significant pest of Oryza sativa (rice) that oviposits inside rice stems. Egg extraction from the stem runs the risk of mechanical damage and hatching is heavily influenced by the micro-environment of the rice stem. To bypass these issues, we targeted embryos prior to oviposition via direct parental (DIPA)-CRISPR, in which Cas9 and single-guide RNAs (sgRNAs) for the WBPH eye pigment gene tryptophan 2,3-dioxygenase were injected into the hemocoel of adult females. Females at varying numbers of days posteclosion were evaluated to determine at what stage their oocyte might be most capable of taking up the gene-editing components. An evaluation of the offspring indicated that the highest G0 gene-edited efficacy (56.7%) occurred in females injected 2d posteclosion, and that those mutations were heritably transmitted to the G1 generation. This study demonstrates the potential utility of DIPA-CRISPR for future gene-editing studies in non-model insect species and can facilitate the development of novel pest management applications.

RNA sequencing analysis reveals that missense mutation in SOX10 is associated with iris color phenotype in quail.

To investigate the molecular mechanisms underlying the differences in iris color in quail, the transcriptome of iris tissue from black quail and Korean quail at day 10 of hatching was RNA sequenced in this study. The differentially expressed genes (DEGs) were screened, functionally annotated and enriched after the quality control and mapping of the raw data. RT-qPCR validation was performed using EIF2S3 as an internal reference gene. The screened SNPs were studied by bioinformatics analysis and iris color correlation analysis. The results showed that there were 425 upregulated genes and 364 downregulated genes in 789 DEGs. Gene Ontology (GO) enrichment analysis revealed that 139 DEGs were significantly enriched in 154 GO terms. The Kyoto Encyclopedia of Genes and Genomes enrichment results showed that the Notch signaling pathway, melanogenesis and tyrosine metabolism were associated with pigment synthesis (p < 0.05). The expression levels of the ASIP, MLPH, PMEL, TYR and SOX10 genes were significantly different in black quail iris and Korean quail iris, as verified by RT-qPCR. The SOX10 gene c.324G>C mutation, which caused the replacement of p.Glu108Asp, had a highly significant correlation with iris color in black quail and Korean quail, which may be one of the reasons for different in iris color between these two quail species.

Iris color and day-night changes in the sympathovagal ratio.

Iris melanocytes are innervated by parasympathetic and sympathetic nerve endings. Light affects autonomic nervous system activity via the retino-hypothalamic pathway. The hypothesis that the day-to-night variations in the sympatovagal ratio (LF/HF) may differ among individuals with different brown iris patterns was tested. A total of 621 healthy adults, aged between 16 and 50, with brown eyes and not diagnosed with a disease that might affect the autonomous nerve system were included in the study. A digital camera was used to acquire iris photos. Subjects were grouped into iris color groups (2-0 bg, 1-0 bg, 1-1 db, 1-1lb, 2-0 b, and 1-0 b). Iris photos were analyzed with Picture Color Analyzer RBG software. The Central/Peripheral (R/RGB) ratio was used for objective distinction between the groups. Using 24-h Holter ECG monitoring, the change in the sympathovagal ratio from day (between 07:00 and 23:00h) to night (between 23:00 and 07:00h) was determined with the formula [(Day-Night) LF/HF)/Day LF/HF]. The frequency of subjects with a decrease in the LF/HF ratio from day to night was the highest in the 1-1 db group (65.7%), followed by the 1-1lb group (56.4%). The highest increase was in the 2-0 bg group (76.5%), followed by the 1-0 B group (68.9%) (p < 0.001). Based on the findings of this study, iris color may be a predictive factor in diseases in which the circadian change of autonomic nervous system activity is effective.

Worldwide Incidence of Ocular Melanoma and Correlation With Pigmentation-Related Risk Factors.

The worldwide incidence of ocular melanoma (OM), uveal melanoma (UM), and conjunctival melanoma has last been reported on 15years ago. Recently, light iris color and four specific single-nucleotide-polymorphisms (SNPs) have been identified as a UM-risk factor. Furthermore, six iris color predicting SNPs have been discovered (IrisPlex). Interestingly, two of these (rs129138329 and rs12203592) are also UM-risk factors. We collected worldwide incidence data of OM and investigated its correlations with iris color, IrisPlex SNPs, and UM-risk SNPs. Cases of OM, as defined by the International Classification of Diseases Oncology C69 (eye), 8720/3 to 8790/3 (malignant melanoma), and 8000 to 8005 (malignant neoplasm), between 1988 and 2012, were extracted from the Cancer Incidence in Five Continents. Incidence rates were age-standardized and their trends were analyzed with joinpoint regression and age period cohort modeling. Frequencies for each country of iris color, IrisPlex SNPs, and UM-risk SNPs were collected from the literature. Incidence rates were generally ≥8.0 cases per million person-years in Northern Europe, Western Europe, and Oceania; 2.0 to 7.9 in North America, Eastern Europe, and Southern Europe; and <2.0 in South America, Asia, and Africa. OM incidence correlated with latitude (r = 0.77, P ≤ 0.001) and is expressed as a north-to-south decreasing gradient in Europe. SNP rs12913832 correlated with OM incidence (r = 0.83, P ≤ 0.001), blue iris color (r = 0.56, P ≤ 0.05), green iris color (r = 0.51, P ≤ 0.05), and brown iris color (r = -0.64, P ≤ 0.01). Trends were stable for most countries (28/35). OM incidence is highest in populations of European ancestry and lowest in populations of Asian and African ancestry. Overall, trends are stable, and the spatial correlation among OM incidence, iris color, and rs12913832 may support the role of pigmentation-related risk factors in OM development.

Operationalisation of the ForenSeq® Kintelligence Kit for Australian unidentified and missing persons casework

Single nucleotide polymorphism (SNP) genotyping technologies can generate investigative leads for human remains identification, including estimation of biological sex, biogeographical ancestry (BGA), externally visible characteristics (EVCs), identity, uniparental lineage and extended kinship. The ForenSeq® Kintelligence Kit provides forensic laboratories with the ability to apply this suite of genetic tools to forensic samples using one panel targeting 10,230 SNPs (including 56 ancestry-informative, 24 phenotype-informative, 94 identity-informative, 106 X chromosome, 85 Y chromosome and 9867 kinship-informative SNPs) sequenced on the MiSeq FGx® Sequencing System. The ForenSeq® Kintelligence Kit has been internally validated, optimised and operationalised by the Australian Federal Police National DNA Program for Unidentified and Missing Persons (AFP Program) for coronial casework. The internal validation was conducted according to the Scientific Working Group on DNA Analysis Methods guidelines (excluding mixture analysis), focussing on sample types typically encountered in human remains identification casework, such as bones, teeth, nail, blood and hair. The workflow was optimised for a high throughput library preparation and sequencing workflow, and additional analytical thresholds were developed to improve genotyping accuracy for low DNA input samples. Additionally, the genetic intelligence generated from the kit was compared to the self-declared biological sex, EVCs and BGA of the DNA donors to assess concordance. The kit was able to produce high quality SNP profiles from 1.0 ng down to 0.1 ng of DNA, with high repeatability and reproducibility, and minimal background noise. The prediction accuracy for biological sex (95%), hair colour (58%), eye colour (74%) and BGA inferences (consistent: 74%; partially consistent: 10%; inconclusive: 16%) was determined based on self-declared data. Additionally, SNP profiles from a volunteer family group of ten related individuals were uploaded to GEDmatch PRO™ to assess kinship accuracy. The kit was capable of detecting (97%) and accurately classifying (90%) genetic relationships spanning from first to fifth degree. The Kintelligence Kit provides the AFP Program with a robust and reliable genetic intelligence tool for unidentified and missing persons investigations, which has been designed to sequence multiple challenging samples in a single multiplexed assay using existing laboratory instrumentation.

Effects of different conditions on the artificial incubation effect and physiological indexes of redclaw crayfish eggs

We explored the effects of different conditions on the artificial incubation of redclaw crayfish eggs in an effort to improve this process. Samples at the egg and juvenile stages were selected. The samples at different stages were separated from the pleopods, then they were placed in incubator boxes and sterilized with different disinfectant solutions. The density was 300,400 and 500 eggs/incubator box, the vibration frequency was 11,16 and 26 vibrations/min, and the water circulation cycle was 2.1, 4.8 and 7.1 cycles/h. The results showed the eggs disinfected with 3000 ppm formaldehyde for 15 min had stronger antioxidant capacity. The hatching and survival rates of five pairs of appendage stage group were significantly lower than those of other groups. In the egg stage, acid phosphatase (ACP) level of compound eye pigmentation stage group was significantly higher than those of other groups. In the juvenile stage, malondialdehyde (MDA) content of five pairs of appendage stage group was significantly higher than those of other groups. The survival rate of 500 eggs/box group was significantly higher than that of other groups. In the egg stage, alkaline phosphatase (AKP) level of 400 eggs/box group was significantly higher than that of other groups. The survival rate of 11 vibrations/min group was significantly higher than that of other groups. In the egg stage, ACP and AKP levels of 11 vibrations/min group were significantly higher than those of 26 vibrations/min group. In the juvenile stage, superoxide dismutase (SOD), ACP and AKP levels of 11 vibrations/min group was significantly higher than those of 26 vibrations/min group. In the juvenile stage, AKP level of 4.8 cycles/h group was significantly lower than that of other groups. In conclusion, egg development at the stage after seven pairs of appendages, with a density of 400 eggs/box, vibration frequencies set at 11 vibrations/min achieved high hatching rates (93.58 %) and survival rates (75.67 %). Moreover, bronopol or hydrogen peroxide might have a better choice to replace formaldehyde if further exploration was conducted to reduce stimulation of the in vitro-grown egg. These conditions could be used on a large scale to optimize the production of redclaw crayfish.

Variations in Phenotypic Characteristics of Vigna Unguiculata (L) Walp. Seeds Sourced From Open Markets in Benin City, Nigeria

Vigna unguiculata, ‘cowpea,’ is a crop of numerous varieties. In Benin City, Nigeria, the three common varieties are “Ife Brown”, “Ekpoma Local”, and “Sokoto White”. Being a very common delicacy and perhaps a cheap source of protein for the population, it is sold in nearly all available open markets. The crop is mainly consigned from numerous farms in the north and thus, is very amenable to genetic diversity. This study was undertaken to investigate the differences within and between these varieties. The seeds obtained from major open markets in Benin City were morphologically characterised quantitatively and qualitatively using standard descriptors. Seed length, width, thickness, weight, and volume were the quantitative parameters, while the qualitative parameters included seed brilliance, shape, eye colour, eye pattern, splitting of testa, testa texture, basal colour, pattern of variegation, colour of variegation, and basal colour of variegated seeds. Only “Ife Brown” varied in qualitative parameters, particularly the seed colour. Among the seed quantitative parameters measured, seed volume was the most diverse, with “Sokoto White” being significantly diverse compared to the others. “Ife Brown” was the most varied species among the three in the markets of Benin City, with a group mean sum of squares of 146.95.