Color Variants Research Articles

Assessment of variations in productive performance of two different plumage color varieties of Japanese quail and their reciprocal crosses

This study aimed to detect the phenotypic differences between the brown (BB) and white (WW) feathered quails and their reciprocal crosses (BW and WB) over two successive generations. The WW and cross quails, especially the BW, had the heaviest body weights, throughout the studied period, with significant variations between the two studied generations (P<0.05). Moreover, the WW and BW possessed the largest egg production during the F1, while in the F2, the BB had superiority among the studied quails with a prominent superiority of the F2 over the F1 (P<0.05). However, the F1 had higher egg weights than F2 with superiority of WW quails compared to the others (P<0.05). Also, the WW quails had the lowest lipid contents of the eggs. These phenotypic variations among the studied quails might be preliminarily explained by the results of the analyzed microsatellite markers despite the few markers used. The high variability among the BW and WB quails might be due to the larger number of alleles (NA and Ne) and the lower values of FIS with low heterozygosity levels (HO and He). Moreover, the BW and BB were the closest, while WB and WW were the farthest because of the high and low genetic identities and the high and low genetic distance between them, respectively. So the obtained results might introduce an initial scientific basis for evaluating and employing the genetic properties of BB, WW, BW, and WB quails in further genetic improvement program, and more microsatellite markers are recommended.

Brown and grey morphs differ in their nocturnality in the polymorphic scops owl (Otus scops)

Detectability of morphs in different light environments is one of the mechanisms favoring the persistence of color polymorphism via disruptive selection. This mechanism predicts that different morphs should be more active and successful when light conditions make them more cryptic. In nocturnal birds, no study has analyzed yet whether morphs show a different degree of nocturnality, showing different circadian activity rhythms in relation to night and day light. We analyze activity patterns and hunting efficiency of color morphs in relation to day/night light in the nocturnal polymorphic scops owl (Otus scops). Forty-four percent of owl activity took place in the first hours after sunrise and before sunset. Also, we found that nocturnal activity decreased from grey to brown females and that grey males fed their chicks more than brown ones at night. Visual modeling revealed that grey individuals would be more conspicuous to their prey than brownish ones during the day. These findings suggest that part of the activity of nocturnal scops owls may occur during the day and that grey individuals would be better adapted to forage during night-light than brownish ones. However, brown morphs seemed not to be better adapted to forage at day, suggesting that other mechanisms than visual detection by predators or prey contribute to the persistence of color polymorphism in the species.Significance statementCircadian activity patterns can vary intraspecifically in response to changing environmental conditions. Color variants in polymorphic species could change their circadian activity rhythms differently in relation to diel luminal variation, switching from nocturnality to diurnality or vice versa, to achieve better background matching. We study for the first time whether different color variants of the nocturnal polymorphic scops owl (Otus scops) show different circadian activity rhythms with respect to night and day light conditions by relying on GPS-tracking data and nest video recordings. We also use perceptual visual modeling to study crypsis of morphs during the day. We found that nearly half of the activity of owls took place in the first hours after sunrise and before sunset. Also, we found that grey individuals would be better adapted to forage during night-light than more brownish ones probably due to their poor background matching during the day for the visual system of insects. These results support the idea that in scops owls, color morphs may show different degree of nocturnality to improve their crypsis.

A frame-shift mutation in COMTD1 is associated with impaired pheomelanin pigmentation in chicken.

The biochemical pathway regulating the synthesis of yellow/red pheomelanin is less well characterized than the synthesis of black/brown eumelanin. Inhibitor of gold (IG phenotype) is a plumage colour variant in chicken that provides an opportunity to further explore this pathway since the recessive allele (IG) at this locus is associated with a defect in the production of pheomelanin. IG/IG homozygotes display a marked dilution of red pheomelanin pigmentation, whilst black pigmentation (eumelanin) is only slightly affected. Here we show that a 2-base pair insertion (frame-shift mutation) in the 5th exon of the Catechol-O-methyltransferase containing domain 1 gene (COMTD1), expected to cause a complete or partial loss-of-function of the COMTD1 enzyme, shows complete concordance with the IG phenotype within and across breeds. We show that the COMTD1 protein is localized to mitochondria in pigment cells. Knockout of Comtd1 in a mouse melanocytic cell line results in a reduction in pheomelanin metabolites and significant alterations in metabolites of glutamate/glutathione, riboflavin, and the tricarboxylic acid cycle. Furthermore, COMTD1 overexpression enhanced cellular proliferation following chemical-induced transfection, a potential inducer of oxidative stress. These observations suggest that COMTD1 plays a protective role for melanocytes against oxidative stress and that this supports their ability to produce pheomelanin.

Topics and trends in fresh tea (Camellia sinensis) leaf research: A comprehensive bibliometric study.

Tea plant (Camellia sinensis) is a widely cultivated cash crop and tea is a favorite functional food in the world. Fresh tea leaves (FTLs) play a critical role in bridging the two fields closely related to tea cultivation and tea processing, those are, tea plant biology and tea biochemistry. To provide a comprehensive overview of the development stages, authorship collaboration, research topics, and hotspots and their temporal evolution trends in the field of FTLs research, we conducted a bibliometric analysis, based on 971 publications on FTLs-related research published during 2001-2021 from Web of Science Core Collection. CiteSpace, R package Bibliometrix, and VOSviewer were employed in this research. The results revealed that the development history can be roughly divided into three stages, namely initial stage, slow development stage and rapid development stage. Journal of Agricultural & Food Chemistry published most articles in this field, while Frontiers in Plant Science held the highest total citations and h-index. The most influential country, institution, and author in this field was identified as China, the Chinese Academy of Agricultural Sciences, and Xiaochun Wan, respectively. FTLs-related research can be categorized into three main topics: the regulation mechanism of key genes, the metabolism and features of essential compounds, and tea plants' growth and stress responses. The most concerning hotspots are the application of advanced technologies, essential metabolites, leaf color variants, and effective cultivation treatments. There has been a shift from basic biochemical and enzymatic studies to studies of molecular mechanisms that depend on multi-omics technologies. We also discussed the future development in this field. This study provides a comprehensive summary of the research field, making it easier for researchers to be informed about its development history, status, and trends.

Cloning and structural basis of fluorescent protein color variants from identical species of sea anemone, Diadumene lineata

Diadumene lineata is a colorful sea anemone with orange stripe tissue of the body column and plain tentacles with red lines. We subjected Diadumene lineata to expression cloning and obtained genes encoding orange (OFP: DiLiFP561) and red fluorescent proteins (RFPs: DiLiFP570 and DiLiFP571). These proteins formed obligatory tetramers. All three proteins showed bright fluorescence with the brightness of 58.3 mM−1·cm−1 (DiLiFP561), 43.9 mM−1·cm−1 (DiLiFP570), and 31.2 mM−1·cm−1 (DiLiFP571), which were equivalent to that of commonly used red fluorescent proteins. Amplitude-weighted average fluorescence lifetimes of DiLiFP561, DiLiFP570 and DiLiFP571 were determined as 3.7, 3.6 and 3.0 ns. We determined a crystal structure of DiLiFP570 at 1.63 Å resolution. The crystal structure of DiLiFP570 revealed that the chromophore has an extended π-conjugated structure similar to that of DsRed. Most of the amino acid residues surrounding the chromophore were common between DiLiFP570 and DiLiFP561, except M159 of DiLiFP570 (Lysine in DiLiFP561), which is located close to the chromophore hydroxyl group. Interestingly, a similar K-to-M substitution has been reported in a red-shifted variant of DsRed (mRFP1). It is a striking observation that the naturally evolved color-change variants are consistent with the mutation induced via protein engineering processes. The newly cloned proteins are promising as orange and red fluorescent markers for imaging with long fluorescence lifetime.Graphical abstract

Association between Variants in the OCA2-HERC2 Region and Blue Eye Colour in HERC2 rs12913832 AA and AG Individuals

The OCA2-HERC2 region is strongly associated with human pigmentation, especially eye colour. The HERC2 SNP rs12913832 is currently the best-known predictor for blue and brown eye colour. However, in a previous study we found that 43 of 166 Norwegians with the brown eye colour genotype rs12913832:AA or AG, did not have the expected brown eye colour. In this study, we carried out massively parallel sequencing of a ~500 kbp HERC2-OCA2 region in 94 rs12913832:AA and AG Norwegians (43 blue-eyed and 51 brown-eyed) to search for novel blue eye colour variants. The new candidate variants were subsequently typed in a Norwegian biobank population (total n = 519) for population specific association analysis. We identified five new variants, rs74409036:A, rs78544415:T, rs72714116:T, rs191109490:C and rs551217952:C, to be the most promising candidates for explaining blue eye colour in individuals with the rs12913832:AA and AG genotype. Additionally, we confirmed the association of the missense variants rs74653330:T and rs121918166:T with blue eye colour, and observed lighter skin colour in rs74653330:T individuals. In total, 37 (86%) of the 43 blue-eyed rs12913832:AA and AG Norwegians could potentially be explained by these seven variants, and we suggest including them in future prediction models.

Characterization and performance evaluation of indigenous geese of Assam

The present study aimed to phenotypically characterize the indigenous geese of Assam, in North East India. These geese were observed to have two types of plumage colour (white and cinnamon) and plumage pattern (solid and bordered); and three different bill colours (black, orange, yellow). The shank and feet colour was found to be mostly orange and sometimes yellow. The eye colour was found to be black, brown and sometimes grey and skin colour as white. The least squares means for body weight at hatching, 4, 6-8 and 12 months and above age were 0.087±0.001, 3.030±0.022, 3.480±0.055 and 3.970±0.025 kg, respectively. The average age at first egg, annual egg production, clutch size and clutch interval were 320.196±2.882 days, 19.886±0.306, 9.897±0.143 and 59.206±0.531 days. Average fertility and hatchability percentage under natural condition were found to be 87.11% and 80.53%, respectively. The study revealed that the indigenous geese of Assam are heavier birds with high potential for meat production with two colour variants, viz. White and Cinnamon in the study area covering four districts. The study generated baseline information on physical characteristics, productive and reproductive performances of indigenous geese of Assam under native field condition which would be of great help in documentation and development of breed descriptors for registration, improvement and conservation.

The MC1R r allele does not increase melanoma risk in MITF E318K carriers.

Population-wide screening for melanoma is not cost-effective, but genetic characterization could facilitate risk stratification and targeted screening. Common Melanocortin-1 receptor (MC1R) red hair colour (RHC) variants and Microphthalmia-associated transcription factor (MITF) E318K separately confer moderate melanoma susceptibility, but their interactive effects are relatively unexplored. To evaluate whether MC1R genotypes differentially affect melanoma risk in MITF E318K+ vs. E318K- individuals. Melanoma status (affected or unaffected) and genotype data (MC1R and MITF E318K) were collated from research cohorts (five Australian and two European). In addition, RHC genotypes from E318K+ individuals with and without melanoma were extracted from databases (The Cancer Genome Atlas and Medical Genome Research Bank, respectively). χ2 and logistic regression were used to evaluate RHC allele and genotype frequencies within E318K+/- cohorts depending on melanoma status. Replication analysis was conducted on 200 000 general-population exomes (UK Biobank). The cohort comprised 1165 MITF E318K- and 322 E318K+ individuals. In E318K- cases MC1R R and r alleles increased melanoma risk relative to wild type (wt), P < 0.001 for both. Similarly, each MC1R RHC genotype (R/R, R/r, R/wt, r/r and r/wt) increased melanoma risk relative to wt/wt (P < 0.001 for all). In E318K+ cases, R alleles increased melanoma risk relative to the wt allele [odds ratio (OR) 2.04 (95% confidence interval 1.67-2.49); P = 0.01], while the r allele risk was comparable with the wt allele [OR 0.78 (0.54-1.14) vs. 1.00, respectively]. E318K+ cases with the r/r genotype had a lower but not significant melanoma risk relative to wt/wt [OR 0.52 (0.20-1.38)]. Within the E318K+ cohort, R genotypes (R/R, R/r and R/wt) conferred a significantly higher risk compared with non-R genotypes (r/r, r/wt and wt/wt) (P < 0.001). UK Biobank data supported our findings that r did not increase melanoma risk in E318K+ individuals. RHC alleles/genotypes modify melanoma risk differently in MITF E318K- and E318K+ individuals. Specifically, although all RHC alleles increase risk relative to wt in E318K- individuals, only MC1R R increases melanoma risk in E318K+ individuals. Importantly, in the E318K+ cohort the MC1R r allele risk is comparable with wt. These findings could inform counselling and management for MITF E318K+ individuals.

Bear essentials

Strangely, American black bears come in many colours. New work by Puckett et al. shows that a missense alteration in the gene encoding tyrosinase-related protein 1 (TYRP1) likely interferes with melanin synthesis and is responsible for the cinnamon colour variant in the southwest USA. However, the adaptive significance of colour polymorphisms in this large carnivore remains opaque.

Species boundaries among extremely diverse and sexually dimorphic Arrenurus water mites (Acariformes: Hydrachnidia: Arrenuridae)

Arrenurus (Arrenuridae) is the most species-rich genus of mites with about 1000 named species that inhabit standing, and to a lesser extent, running water habitats around the world. To date, distinguishing species of Arrenurus has been based on male reproductive morphology. Here, we use morphological and molecular approaches to examine species boundaries among 42 named species of Arrenurus, including four named species that have colour variants (red and green A. americanus, and red and blue A. intermedius, A. manubriator and A. apetiolatus), and two unnamed morphospecies. In this study, we examine male genital structures with the use of SEM techniques, and apply mitochondrial (COI barcode region) and nuclear (28S rRNA) gene fragments to test whether male morphology reflects species boundaries in Arrenurus assessed by molecular analyses. Our results reveal that male reproductive morphology parallels species boundaries as judged by molecular data. We discuss the cases of genetically poorly diversified, yet morphologically clearly defined named species. Moreover, we show that based on the species we examined, colour morphs within otherwise morphologically similar specimens represent within-species variation and, in the absence of other diagnostic traits, colour itself can be misleading in distinguishing species. Our outcomes on molecular taxonomy of Arrenurus provide a background for testing hypotheses about speciation rate in water mites.

Does colour variety accurately quantify nutritional value in children's lunchboxes? A pilot study

ObjectivesIn advocating a diet rich in fruit and vegetables, public health authorities emphasise dietary colour variety to ensure adequate nutrient consumption. The relationship between food colour variety and nutritional value in children's lunches attending one school was evaluated. Study designObservational cross-sectional study. MethodsEighty-two children had their lunchboxes photographed over one day. Foods were scored using the Nutri-score labelling system, assigning foods a letter based on nutritional content. Composite Nutri-scores were calculated as average total Nutri-score per food per lunchbox. Eleven observers used a colour chart to assign colours to foods from a sample of lunchboxes; intra-class correlation was calculated. Associations between nutrient scores and colour variety were estimated. ResultsLunchboxes contained an average of 4 ± 1 colours. Number of colours did not vary by age or sex. Two thirds of lunches had composite Nutri-scores of C or better, with better scores in older children. There was no association between colour variety and composite Nutri-score. Fruit, vegetables, whole grains and fats were associated with greater colour variety. Vegetables and meat, fish and eggs were associated with better scores; refined grains, dairy, snacks, fats and condiments were associated with worse. ConclusionsAlthough this study did not demonstrate a relationship between colour variety and nutritional score, findings suggest that lunches containing fruit and vegetables tended towards greater colour variety than those without. This indicates that adjusting guidelines to incorporate food colour variety may be of use in future iterations of dietary guidelines for children.

AMPK Phosphorylates ZDHHC13 to Increase MC1R Activity and Suppress Melanomagenesis.

Phosphorylation of ZDHHC13 by AMPK at S208 promotes MC1R activation and suppresses melanocyte transformation, indicating activation of AMPK as a potential approach to prevent melanoma in people with red hair.

Recent Progress in Breeding for Beta-Carotene, Dry Matter Content and Sugar in Sweet potato [Ipomoea Batatas (L.) Lam]-A Review

In several developing countries, root and tuber crops play a crucial role in food security as well as in agriculture. Based on production and consumption, sweet potato [Ipomoea batatas (L.) Lam] plays a significant role after potato among the root and tuber crops. Today, sweet potato breeding program focus on multiple purposes. There are four sweet potato breeding platforms (three in Africa) and in SSA there are four breeding centers (three in West Africa). High levels of β‐carotene, phenolics, anthocyanins, vitamins, fiber, dietary, minerals, and other bioactive compounds content depends on the flesh color of sweet potatoes. The orange‐fleshed sweet potato types contain high β‐carotene levels and low dry matter content. White‐cream fleshed color varieties have high dry matter (&gt;30%). The purple‐fleshed sweet potato varieties with attractive color and high anthocyanin content are the most preferred in Asia. Sweet potato with low in sweetness and higher dry matter (28–30%) are the specially of most parts of sub-Saharan Africa. Consuming β‐carotene leads as a viable long‐term food‐based strategy for combating the deficiency vitamin A in the world. The sweet potato dry matter content up of 80-90% carbohydrates and exists in the form of starch and sugars non-starch polysaccharides. The primary contributors to the taste of the sweet potato are sugars and organic acids. The strong flavor and high levels of sweetness may have affected the popularity of sweet potato as a staple food. Due of the negative correlation between traits, breeding for high B-carotene and dry matter with low sugar in one variety has remained a challenge, although it was reported that recurrent mass selection should be possible to accumulate favorable alleles so that progress can be made over.

Selection and Admixture in a Polytypic Aposematic Frog.

AbstractPhenotypic differentiation within polytypic species is often attributed to selection, particularly when selection might be acting on a trait that serves as a signal for predator avoidance and mate choice. We evaluated this hypothesis by examining phenotypic and genotypic clines between populations of the strawberry poison frog Oophaga pumilio, a polytypic species that exhibits aposematic color pattern variation that is thought to be subject to both natural and sexual selection. Our aim was to assess the extent of admixture and to estimate the strength of selection acting on coloration across a region of Panama where monomorphic populations of distinctly colored frogs are separated by polymorphic populations containing both color variants alongside intermediately colored individuals. We detected sharp clinal transitions across the study region, which is an expected outcome of strong selection, but we also detected evidence of widespread admixture, even at sites far from the phenotypic transition zone. Additionally, genotypic and phenotypic clines were neither concordant nor coincident, and with one exception, selection coefficients estimated from cline attributes were small. These results suggest that strong selection is not required for the maintenance of phenotypic divergence within polytypic species, challenging the long-standing notion that strong selection is implicit in the evolution of warning signals.

Convergent changes in melanocortin receptor 1 gene are associated with black-headed coat color in sheep

As one of the most obvious phenotypic traits, the coat color of sheep is an ideal model to study the genetic mechanisms underlying coat color varieties of mammals. One distinguishable coat color is the black-headed type, such as the famous black-headed Dorper sheep from Africa and Bayinbuluke sheep from Asia. In this study, we compared the genome sequences of black-headed and all-white sheep to identify causative genes for the black-headed sheep, including black-headed Dorper vs. white-headed Dorper, as well as Bayinbuluke (black-headed) vs. Small-tailed Han (all-white). The most differentiating region between black-headed sheep and all-white sheep was found to harbor a haplotype covering melanocortin receptor 1 (MC1R) gene. The share of this haplotype by the black-headed sheep from Africa and Asia suggested that the convergent change in the MC1R region is likely to determine this unique coat color. Two missense mutations (g. 14251947T > A and g. 14252090G > A) within this haplotype of MC1R gene were found. We further analyzed whole genome sequence data of 460 worldwide sheep with diverse coat colors and confirmed the association between the MC1R haplotype with pigmentation variations. Our study provides novel insights into coat color genetics in sheep and expands our knowledge of the link between MC1R gene and varying pigmentation patterns in sheep.

Two coral fluorescent proteins of distinct colors for sharp visualization of cell-cycle progression.

We cloned and characterized two new coral fluorescent proteins: h2-3 and 1-41. h2-3 formed an obligate dimeric complex and exhibited bright green fluorescence. On the other hand, 1-41 formed a highly multimeric complex and exhibited dim red fluorescence. We engineered 1-41 into AzaleaB5, a practically useful red-emitting fluorescent protein for cellular labeling applications. We fused h2-3 and AzaleaB5 to the ubiquitination domains of human Geminin and Cdt1, respectively, to generate a new color variant of Fucci (Fluorescent Ubiquitination-based Cell-Cycle Indicator): Fucci5. We found Fucci5 provided more reliable nuclear labeling for monitoring cell-cycle progression than the 1st and 2nd generations that used mAG/mKO2 and mVenus/mCherry, respectively.Key words: fluorescent protein, cell cycle, time-lapse imaging, flow cytometry.

Analisis Penetapan COGM (Cost Of Goods Manufactured) Dengan ABC (Activity Based Costing) Sebagai Metode Pengukuran Harga Jual

The determination of COGM or the cost of production in a company is very important for making decisions on the selling price of a product. Therefore, the determination of methods that produce appropriate and accurate sources of data and information becomes a consideration in business continuity in the future. The ABC (Activity Based Costing) method is one method that is well known for its accuracy compared to traditional/conventional methods. The object of this research is the ITS Back To Nature Business, which is a business engaged in manufacturing by producing marker ink with three color variants, namely black, blue, and red. This business still applies the traditional system in determining COGM or the cost of production. This study aims to determine the accuracy of the two methods of determining COGM by comparing the traditional/conventional method and the ABC (Activity Based Costing) method in measuring the selling price later. This research is classified as a part of qualitative research that adheres to a descriptive approach by providing a systematic description of COGM (Cost Of Goods Manufactured) or the cost of production through the ABC method. Observations, interviews, and documentation are techniques or methods of collecting data in this study. In the findings of this study, the results obtained where the ABC method applied showed a lower cost of goods compared to the traditional/conventional method with a difference of IDR 726 for black ink products, IDR 646 for blue ink, and IDR 1,035 for red ink. This, of course, greatly affects the company's price competitiveness in the market.

Integrative redescription of the enigmatic monotypic alpine pill millipede genus Simplomeris Verhoeff, 1936 (Glomerida, Glomeridae, Haploglomerinae)

The European pill millipedes (Glomerida) are especially rich in species and genera of enigmatic status, which have been neither reviewed nor revised since more than 70 years. One of these genera is Simplomeris Verhoeff, 1936 with its single species S. montivaga (Faës, 1902), a high-altitude endemic only known from <5 collection events in the Simplon Valley and the Aletsch Glacier, southern Switzerland. Being one of only a handful of genera in the subfamily Haploglomerinae, distributed in Europe and SE Asia, its morphology is of greater interest in a future phylogenetic sorting of the Glomerida. Fresh material, which was encountered by the author 10 years ago from both known localities, allows here a redescription of this rarely encountered genus. Aside from the first photograph of a living specimen, scanning electron microscopy and genetic barcoding of the COI gene have been conducted. Morphologically, the telopods of Simplomeris resemble those of Haploglomeris Verhoeff, 1906 from the eastern Alps and confirm the present position in the Haploglomerinae. Genetically, Simplomeris belongs to the Glomeris klugii Brandt, 1833 species-group and is particularly close to high-altitude endemics from the southwestern and Bergamasque Alps, especially G. primordialis Verhoeff, 1930, G. transalpina Koch, 1836, and G. oropensis Verhoeff, 1934. Genetic barcoding data confirm the three colour varieties of S. montivaga, S. montivaga var. montivaga Verhoeff, 1936 syn. nov., S. montivaga var. simplonensis Verhoeff, 1936: syn. nov., S. montivaga var. berisalensis Verhoeff, 1936 syn. nov. to be just that, and all three are formally synonymized under S. montivaga.

Comparative analysis of genetic diversity and structure among four shell color strains of the Pacific oyster Crassostrea gigas based on the mitochondrial COI gene and microsatellites

Shell color is one of the major determinants in the popularity of shelled seafood. To enhance the commercial value of the Pacific oyster (Crassostrea gigas), four shell color strains of black (SB), white (SW), gold (SG), and orange (SO) were bred purposefully for 11–12 generations. In this study, CIELAB colorimetric analysis was used to evaluate the effectiveness of shell color selection of C. gigas. The color parameters (L⁎, a⁎, b⁎) by statistical analysis differed significantly across black, white, gold, and orange shell strains (P < 0.05), and the principal component analysis characterized the considerable improvement in shell color uniformity. Further, we carried out genetic analysis by 15 microsatellites and mitochondrial cytochrome oxidase I sequences (mtCOI). A total of 121 alleles were detected at all 15 microsatellite loci, with the average number of alleles per locus ranging from 4.07 in SO to 7.67 in SW. Compared with wild populations, the shell color strains had significantly fewer alleles and mtCOI haplotypes, but the average heterozygosity, including Ho from 0.52 to 0.66 and He from 0.59 to 0.75, was not statistically different (P < 0.05). The SO samples suffered the greatest loss of diversity and occupied the lowest value of all genetic diversity indices, which is likely due to the smaller size of founding stock resulting in a stronger bottleneck. Population simulation analysis showed that the genetic background of four shell color strains was completely separated, confirming the consistency of phenotypically defined and genetically differentiated populations. Pairwise FST calculated by microsatellites with a range of 0.267 to 0.121 revealed high levels of genetic differentiation among strains, which has far exceeded the divergence between different geographical populations of C. gigas (FST: 0.012–0.034). The results obtained in the study provide valuable information for further genetic improvement of shell color variants through selective breeding.

Effects of heat stress on fattening performance, carcass traits, oxidant/antioxidant status, and hepatic heat shock protein 70 levels in different plumage colors of Japanese quail (Coturnix coturnix japonica).

The aim of this study was to investigate the impact of heat stress on production performance and oxidative stress in different plumage colors of Japanese quail. For this purpose, a total of 100 birds were used in this study. The 25 birds belonged to Wild-type (n=25, grey), Tuxedo (n=25, black), Golden (n=25, yellow) and Recessive white (n=25). The birds were reared for 42 days in an environmentally controlled room at 39°C and relative humidity of 60-65%. The body weight, body weight gain (g/bird/day), and feed conversion ratio were not different between the groups (p>0.05). However, the feed intake (g/bird/day) of the Wild-type had a higher value than the Tuxedo (black) group counterparts between 15 and 21 days different (p⟨0.05). There was no significant effect of heat stress on the carcass traits (p>0.05). Spleen weights were different between the groups (p⟨0.05). The yellow group had the highest spleen weight. The highest MDA level was found in the Recessive White variety, followed by Wild-type (grey), Golden (yellow) and Tuxedo (black), respectively. However, there were no statistical differences amongst the groups (p>0.05). There was also no statistical significance in glutathione (GSH) and superoxide dismutase (SOD) levels (p>0.05). The heat shock protein 70 kDa (HSP70) level was significantly different between the groups (p⟨0.001). The highest percentage was observed in the Golden (5.06%) and the lowest in the White (1.43%) variety. There was no superior color variety of Japanese quail regarding fattening performance and carcass traits. It is conceivable that when considering the stress response of the different colors, the Golden group is more sensitive to stress due to the hepatic and cellular level of HSP70.