Yellow Quail Research Articles

Quail GHRL and LEAP2 gene cloning, polymorphism detection, phylogenetic analysis, tissue expression profiling and its association analysis with feed intake

The GHRL, LEAP2, and GHSR system have recently been identified as important regulators of feed intake in mammals and chickens. However, the complete cloning of the quail GHRL (qGHRL) and quail LEAP2 (qLEAP2) genes, as well as their association with feed intake, remains unclear. This study cloned the entire qGHRL and qLEAP2 cDNA sequence in Chinese yellow quail (Coturnix japonica), including the 5′ and 3′ untranslated regions. Sanger sequencing analysis revealed no missense mutations in the coding region of qGHRL and qLEAP2. Subsequently, phylogenetic analysis and protein homology alignment were conducted on the qGHRL and qLEAP2 in major poultry species. The findings of this research indicated that the qGHRL and qLEAP2 sequences exhibit a high degree of similarity with those of chicken and turkey. Specifically, the N-terminal 6 amino acids of GHRL mature peptides and all the mature peptide sequence of LEAP2 exhibited consistent patterns across all species examined. The analysis of tissue gene expression profiles indicated that qGHRL was primarily expressed in the proventriculus and brain tissue, whereas qLEAP2 exhibited higher expression levels in the intestinal tissue, kidney, and liver tissue, differing slightly from previous studies conducted on chicken. It is necessary to investigate the significance of elevated expression of qGHRL in brain and qLEAP2 in kidney in the future. Further research has shown that the expression of qLEAP2 can quickly respond to changes in different energy states, whereas qGHRL does not exhibit the same capability. Overall, this study successfully cloned the complete cDNA sequences of qGHRL and qLEAP2, and conducted a comprehensive examination of their tissue expression profiles and gene expression levels in the main expressing organs across different energy states. Our current findings suggested that qLEAP2 is highly expressed in the liver, intestine, and kidney, and its expression level is regulated by feed intake.

Expression and Mutation of SLC45A2 Affects Iris Color in Quail.

Iris color is a prominent phenotypic feature of quail. To understand the mechanism of melanin deposition related to quail iris color, iris tissues were selected from Beijing white and Chinese yellow quail for transcriptome analysis. Differentially expressed genes (DEGs) associated with pigmentation were identified using RNA sequencing and validated by quantitative real-time polymerase chain reaction (RT-qPCR). The identified single nucleotide polymorphisms were studied using bioinformatics and iris color correlation analyses. A total of 485 DEGs were obtained, with 223 upregulated and 262 downregulated. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed. Thirty-two genes were annotated using the GO database. Three important pigment synthesis pathways (Notch signaling, melanogenesis, and tyrosine metabolism) were identified in quail iris tissue (P < 0.05). The expression levels of solute carrier family 45 member 2 (SLC45A2), tyrosinase-related protein 1, vitamin D receptor, opsin 5, and docking protein 5 were significantly different between Beijing white and Chinese yellow quail, as verified by RT-qPCR. The c.1061C>T mutation in SLC45A2, which caused a single amino acid change at position 354 (threonine to methionine), was significantly associated with iris color in Beijing white and Chinese yellow quail, and might be the main reason for the different iris colors between these two quail species.

Effects of dietary supplement with licorice and rutin mixture on production performance, egg quality, antioxidant capacity, and gut microbiota in quails (Turnix tanki)

This study was conducted to evaluate the effect of licorice and rutin on production performance, egg quality, and mucosa antioxidant levels in Chinese yellow quail. A total of 240 Chinese Yellow Quail (400-day-old) were randomly distributed into 5 groups: the Control group, fed with a basic diet; the LR1 group, fed with basal diet supplemented with 300+100 mg licorice and rutin mixture/kg diet; the LR2 group, fed with basal diet supplemented with 300+200 mg licorice and rutin mixture/kg diet; the LR3 group, fed with basal diet supplemented with 600+100 mg licorice and rutin mixture/kg diet and the LR4 group, fed with basal diet supplemented with 600+200 mg licorice and rutin mixture/kg diet. Compared with the control, supplementation with the licorice and rutin mixture improved the laying rate and eggshell thickness whereas decreased the feed conversion ratio of quails. Moreover, dietary supplementation with the licorice and rutin mixture improved the antioxidant capacity by increasing the activity of the superoxide dismutase (SOD) level and decreasing the concentration of malondialdehyde (MDA) in the jejunal mucosa. The licorice and rutin mixture altered the composition of intestinal microbiota by influencing the relative abundances of Bacteroidetes and Bacteroides. The relative abundances of the Bacteroidetes were significantly related to the laying rate of quails. In addition, the mixture of licorice and rutin was also effective in reducing the relative abundance of intestinal Proteobacteria and Enterobacter in quails, reducing the accumulation of antibiotic-resistance genes. The results revealed that supplementation of licorice and rutin mixture to the diet improved production performance, egg quality, and antioxidant capacity and modified the composition of intestinal microbiota in quails. This study provides a reference for Chinese herbal additives to promote production performance by modulating quail gut microbes.

The therapeutic mechanism of Chebulae Fructus in the treatment of immunosuppression in Chinese yellow quail on the basis of network pharmacology.

Chebulae Fructus (Terminalia chebula Retz.) is a well-known traditional Chinese medicine (TCM), one of the family Combretaceae, whose immature fruit is called Fructus Chebulae Immaturus or Zangqingguo. This present study aimed at detecting the target and therapeutic mechanism of Chebulae Fructus against immunosuppression through network analysis and experimental validation. Effective components and potential targets of Chebulae Fructus were Search and filtered through the Chinese herbal medicine pharmacology data and analysis platform. A variety of known disease target databases were employed to screen the therapeutic target proteins against immunosuppression and thus constructing a protein-protein interaction network. Hub genes and key pathways in this study were identified by continuous project enrichment analysis. Further, the core targets and therapeutic mechanism of Chebulae Fructus against immunosuppression in Chinese yellow quail through animal experiment. Seventy-five identifiable major candidate targets of Chebulae Fructus were found and thus constructing a drug-compound-target-disease network. Targets derived from gene enrichment analysis play pivotal roles in lipid and atherosclerosis, fluid shear stress and atherosclerosis, and the hepatitis B pathway. Height of plicate and areas of lymphoid follicle were both increased and the expression of GATA-3 and T-bet was upregulated in Chinese yellow quail fed with Chebulae Fructus in animal experiment. Chebulae Fructus may be a helpful Chinese medicine with immunosuppressive effect and prospective applications in future. Further research is also needed to understand the mechanisms of immunosuppression and the mechanism of action of immunomodulators.

Research Note: Association of IGF-1R gene polymorphism with egg quality and carcass traits of quail (Coturnix japonica)

Insulin-like growth factor 1 receptor (IGF-1R) gene is the main effector of insulin-like growth factor (IGF), which plays an important role in growth, development and reproduction of the animal organism. This study aimed to investigate the association of IGF-1R gene single nucleotide polymorphisms (SNPs) with egg quality and carcass traits of quail by direct sequencing. In this study, genomic DNA was extracted from quail blood samples of 46 Chinese yellow (CY) quail, 49 Beijing white (BW) quail and 48 Korean (KO) quail strains. Egg quality and carcass traits were measured and used for IGF-1R gene analysis in 3 quail strains. The results showed that 2 SNPs (A57G and A72T) of the IGF-1R gene were detected in 3 quail strains. The A57G was significantly associated with yolk width (YWI) in BW strain (P < 0.05). Whereas A72T was significantly associated with egg shell thickness (EST) in BW strain (P < 0.05), and significantly associated with egg weight (EW), egg long (EL), and egg short (ES) in KO strain (P < 0.05). Haplotypes based on 2 SNPs showed significant effect on EST in 3 quail strains (P < 0.05), it also has a significant effect on EW in KO strain (P < 0.05). Meanwhile, A72T was significantly associated with liver weight (LW) and dressing percentage (DP) in 3 strains (P < 0.05). Haplotypes showed significant effect on LW (P < 0.05). Therefore, the IGF-1R gene may be a molecular genetic marker to improve egg quality and carcass traits in quails.

Research Note: Effect of Rubia cordifolia L. processed Terminalia chebula Retz polysaccharide on the histological structure and apoptosis in the spleen in immunosuppressed Chinese yellow quail

It is generally accepted herbal polysaccharide and is a bioactive compound of herbal medicines with immunomodulatory activities. It has a wide range of pharmacological effects. It can be used as a green substitute for antibiotics or as a feed additive in quail breeding. Therefore, the herbal polysaccharide has a broader and safer application prospect. The immunosuppressive disease of quail is one of the most important infectious diseases. It seriously affects the growth, development, and production performance of quail, causing huge economic losses to quail industry. However, there is no report on the effective alleviation of spleen injury in immunosuppressed animals by herbal polysaccharide. Therefore, we established a pathological model of immunosuppressive Chinese yellow quail for the first time, with the Terminalia chebula Retz polysaccharide (TCP) as the control, and histological observation, TUNEL staining were used to study the effects of Rubia cordifolia L. processed Terminalia chebula Retz polysaccharide (RTCP) on splenic tissue structure and apoptosis of immunosuppressed Chinese yellow quail. The experimental results showed that spleen organ index of the cyclophosphamide (CTX) group was significantly lower than these of blank control group, the TCP group and the RTCP group (P < 0.05). And the number of splenic nodules in the CTX group was significantly lower than that in the blank control group (P < 0.01). Compared with the CTX group, the spleen volume of the TCP group and the RTCP group increased, and the number and area of spleen nodules increased. Among them, the spleen nodules in the RTCP group were significantly more higher than that in the CTX group (P < 0.01). Meanwhile, TUNEL staining showed that the TUNEL positive cells in the CTX group were the most significantly higher than those in the blank control group (P < 0.01). TCP group and RTCP group were significantly higher than the blank control group (P < 0.01), but significantly lower than CTX group (P < 0.05). All these results suggested that RTCP could effectively improve CTX-induced spleen damage in immunosuppressed Chinese yellow quails by promoting the recovery of spleen organ index, repairing the spleen tissue structure, and diminishing the apoptosis. Moreover, RTCP is more effective than TCP. The results prove that the efficacy of RTCP in protecting spleen from CTX induced injury was enhanced after processing with Rubia cordifolia L. Therefore, our findings will provide more possibilities to promote the clinical application and development of processed traditional Chinese medicine in the further.

Association analysis of ESR gene polymorphism and carcass traits in egg quails (Coturnix coturnix)

The polymorphism of estrogen receptor (ESR) gene was detected by PCR-RFLP in China yellow, Korean and Beijing white quails and the association between ESR gene polymorphism and carcass traits of egg quails was analyzed. The results showed that there were three genotypes including CC, CT and TT detected in exon 1 and exon 8 of ESR gene in egg quails. The frequencies of CC genotype in exon 1 of ESR gene were the highest in China yellow, Beijing white and Korean quail (0.515, 0.614, 0.723). The highest frequencies of TT genotype in exon 8 of ESR gene were detected in Beijing white and Korean quails (0.618 and 0.540), while the highest frequency of CT genotype was detected in China yellow quail (0.476). As demonstrated in this study, there were significant correlations between exon 1 of ESR gene and body weight, carcass weight, breast muscle weight, heart weight and percentage of leg muscles in egg quails (P&lt;0.05).

Association Analysis Between Polymorphism of Gonadotrophin Releasing Hormone Genes and Growth Traits of Quail (Coturnix Coturnix)

ABSTRACT This study investigated SNP mutation sites of Gonadotrophin releasing hormone (GnRH) gene in China yellow quail, Beijing white quail and Korean quail through PCR amplification and DNA sequencing technologies. Moreover, polymorphism of GnRH gene and its association with growth traits of quail were analyzed, aiming to get molecular markers associated to growth traits of quail, which could provide references for breeding of new quail species. According to research results, a total of 14 SNP mutation sites of GnRH were detected in China yellow quail, Beijing white quail and Korean quail, which were C71T, C108T, C168T, C178T, A184G, C206T, A209C, C215T, A252G, A279T, C281T, C293G, C339T and C458T. Except that only 2 genotypes were detected for A209C and C281T in China yellow quail and Beijing white quail, 3 genotypes were detected for all of the remaining 12 SNP mutation sites in three quail species. Of the 14 SNP sites, C71T, A209C, C215T, C281T, C293G, C339T and C458T were significantly associated with body weight (p<0.05), C71T, C108T, C168T, C178T, A184G, C206T, C215T, A252G, C293G, C339T and C458T were significantly associated with shank length (p<0.05), C71T, C215T, C293G and C458T were significantly associated with breastbone length (p<0.05), A209C and C281T were significantly associated with shank circumference (p<0.05).

Association Analysis between Polymorphism of GnRH-1 Genes and Carcass Traits of Quail (Coturnix coturnix)

Background: GnRH-1 mainly exists in hypothalamus and it is vital to gonad development and sexual maturity of animals. This study mainly analyzed the association between GnRH-1 polymorphism and carcass traits of quails, Research conclusions can provide references for breeding of new species of quail.Methods: From 2018 to 2019, 31 female samples of Chinese Yellow quail, beijingbai quail and Korean quail were collected in Luolong District, Luoyang City, Henan Province, China.SNP mutation sites of GnRH-1 gene were investigated in China yellow quail, Beijing white quail and Korean quail through PCR amplification and DNA sequencing technologys. Moreover, correlation analysis between polymorphism sites of GnRH-1 gene and carcass traits of quail was performed. Result: According to research results, a total of 14 SNP mutation sites of GnRH-1 were detected in China yellow quail, Beijing white quail and Korean quail, which were C71T, C108T, C168T, C178T, A184G, C206T, A209C, C215T, A252G, A279T, C281T, C293G, C339T and C458T. For A209C and C281T, only 2 genotypes were detected in China yellow quail and Beijing white quail, while for the remaining 12 SNP mutation sites, 3 genotypes were detected in three quail species. Correlation analysis showed that A209C, A279T, C281T and C339T were significantly correlated with liver weight (P less than 0.05), A209C, C281T and C339T were significantly correlated with dressing percentage (P less than 0.05), C215T and A279T were significantly correlated with breast muscle weight(whole) (P less than 0.05), A209C was significantly correlated with body weight, dressed carcass weight and whole net carcass weight (P less than 0.05).

Sarı tüy rengindeki (Coturnix japonica) bıldırcınlarda farklı yaş ve depolama sürelerinin yumurta kalite özellikleri üzerine etkisi

Amaç: Sarı tüy renkli japon bıldırcınlarında 8, 12, 16, 20, 24, 28 ve 32 haftalık yaşlarda 7 ve 14 gün süreyle depolanan kuluçkalık yumurtaların iç ve dış kalite özellikleri araştırılmıştır.Yöntem ve Bulgular: Yaş ve depolama sürelerinin yumurtalarda dış ve iç kalite özellikleri üzerine etkisini belirme amacıyla 8-32 haftalar arasında 7 ayrı yaş dönemleri yumurtaların 0, 7 ve 14 gün süre ile depolanması araştırmanın yöntemini oluşturmaktadır. Yumurtanın depolama süresinin bağıl ağırlık kaybına etkili olduğu görülmüştür. Yumurta ağırlığı üzerine yaşın etkisi önemli bulunmuş, deneme başlangıcında (8. hafta) 11.67 g olan yumurta ağırlığı deneme sonunda (32. hafta) 12.15 g değerini almıştır Yumurta eninin yumurta boyuna oranı şeklinde ifade edilen şekil indeksi 8 haftalık yaşta en yüksek, 32 haftalık yaşta en düşük belirlenmiştir. Ak indeksi üzerine hayvan yaşı, depolama süresi ve yaş x depolama süresi arasındaki interaksiyon önemli bulunmuştur. Haugh birimi depolama süresi ve hayvan yaşından etkilenmiş, depolama süresi ile yaş arasındaki interaksiyon da etkili olmuştur. Depolama işlemi yapılmayan kontrol grubunda sarı indeks değeri, 7 ve 14 günlük depolama sürelerine göre daha düşük olup uygulamalar arası farklılık önemli bulunmuştur. Ak yüzdesi üzerine depolama süresi, yaş ve depolama süresi ile yaş arasındaki interaksiyon önemli olmuştur. Sarı yüzdesi depolama süresinden etkilenmemiş ancak yaşa bağlı olarak değişmiştir. Artan depolama süresine bağlı olarak sarı indeks değeri azalmıştır. Birim yüzey alanı başına kabuk ağırlığı depolama süresi ve hayvan yaşına göre değişmiştir. Gözenek sayısı üzerine hayvan yaşı etkili iken depolama süresinin etkisi önemsiz olmuştur.Genel Yorum: Sarı tüy rengindeki japon bıldırcınlarında yumurta iç ve dış kalite özellikleri üzerine anaç yaşı, depolama süresi ve çevresel faktörlerin etkisi önemli düzeyde bulunmuştur.Çalışmanın Önemi ve Etkisi: Elde edilen sonuçların gelecekte planlanacak çalışmalar için bilgi sağlayacağı beklenmektedir.

Correlation Analysis between MyoG Gene Polymorphism and Carcass Characteristics of Egg quails

Quail is extensively reared in China for characteristic of quick growth, small fodder consumption, early sexual maturity, high egg output and short production period. In this study, the SNP markers in 5’ regulation regions of cytogenin gene (MyoG) among China yellow quail, Beijing white quail and Korean quail were detected by PCR-SSCP method. Moreover, correlations of MyoG 5’ regulation regions with carcass characteristics of quail were analyzed. Results demonstrated thatin egg quail group, six genotypes were detected in Locus A in the control region of MyoG 5’, including AA, BB, CC, AB, AC and BC. The highest frequencies of CC in China yellow quail, Beijing white quail and Korean quail were 0.323, 0.366 and 0.444, respectively. A total of 9 genotypes were detected in locus B in egg quail group, which were AA, BB, CC, DD, EE, AB, AC, AD and AE. AA showed the highest frequency in China yellow quail, Beijing white quail and Korean quail, which were 0.493, 0.385 and 0.406, respectively. There was significant correlation between locus A and leg muscle rate of egg quail (plessthan0.05). Locus B presented significant correlations with carcass net weight, leg muscle weight, dressing percentage, whole net carcass rate and heart rate (plessthan0.05). Loci A and B in the control region of MyoG 5’ can be used as the molecular marker of carcass characteristics of egg quails during marker assisted selection.

Comparative analysis on early growth and development of different egg-laying quails

This study was carried out to evaluate growth and development and difference between size and weights of three quail species namely China yellow quail, Beijing white quail and Korea quail. Various parameters in respect of these species like shank length, chest width, chest depth, breastbone length, shank circumference, body length, daily weight gain and weight were recorded under similar feeding conditions. The data so obtained was analysed statistically using SPSS. It was revealed that the body weight, shank length, chest width, chest depth, breastbone length, body length, shank circumference and daily gain of Korea quail are significantly higher (P£0.05) than those of China yellow quail and Beijing white quail. It was concluded the Korea quail grows fastest, followed by China yellow quail and Beijing white quail, successively.

Age-related histomorphological studies on the spleen of Chinese yellow quail

This study was aimed to investigate the morphology, growth, histological structure and development of the spleen of the Chinese yellow quail at different ages(from 0 to 38 weeks). The yellow Quail spleen was spherical, brownish red, located at the right dorsal of the junction of the muscle stomach and glandular stomach. The absolute quality, length and width of the spleen gradually increased with age, reaching a maximum for each of these measurements at the age of 6 weeks and then remainied unchanged between 10 and 26 weeks of age. Finally, these measurements of the spleen were no significant difference at 30 weeks of age compared to at 34 to 38 weeks (P&gt;0.05). Although, these measurements were found to gradually decrease during 30-38 weeks of age, the decrease was not obvious. The basic structure of the spleen included red pulp, white pulp and the edge area. In addition, the average area and diameter of the splenic nodules, the white pulp ellipsoid and the periarterial lymphatic sheath gradually increased, reaching maximum sizes at the age of 26 weeks. It was seen that a sustained developmental period occurred at 0-6 weeks of age and a maturation period occurred at 10-38 weeks during the development of quail spleen.

Aplicação da distribuição Burr XII discreta na análise de dados de produção animal

In animal production, the models that mimicry the biological reality are of great importance for optimization and sustainability of the productive system. The continuous Burr XII distribution is widely used in survival data analysis, however, the same does not occur with its discrete version, recently proposed in the literature. The purpose of this work is to use the discrete Burr XII distribution, obtained by the discretization method proposed by Nakagawa and Osaki (1975), in the analysis of data related to animal production. The data analyzed describe the time, in days, from birth to first laying of yellow quail (Coturnix coturnix japonica) submitted to two diets. For this purpose the discretized versions of five distributions were used: the discrete Burr XII, the discrete Weibull, the discrete gamma, the discrete inverse-Gaussian and the discrete log-normal. For all distributions, the parameter estimates were obtained by the maximum likelihood method. Despite the similarity between the estimates it is natural to choose the discrete given the nature of the data and assuming the discrete distribution, it could be calculated exactly, for example, the probability of the time to the first posture, which is not possible if a continuous distribution is assumed. Thus, among the discrete distributions, the chi-square goodness-of-fit test showed that the Burr XII distribution was the only one indicated to describe the behavior of the data considered.

Microsatellite Analysis of Genetic Diversity in Quail Populations from China

Polymorphism of three quail communities was analyzed by using 12 microsatellite markers in this paper, aiming to provide scientific references for the evaluation, protection and utilization of quail genetic resources in China. Results demonstrated that the number of observed alleles by 12 microsatellite markers ranges between 4~7. The average polymorphism information contents (PIC) of the Chinese yellow quail, the Chinese black quail and the Korean quail, as detected by 12 microsatellite markers, are 0.6853, 0.6401 and 0.6565,respectively, and average heterozygosity values are 0.7333, 0.6957 and 0.7111, respectively. This indicates that the Chinese yellow quail has the richest genetic polymorphism. According to cluster analysis, the Chinese black quail and the Korean quail have the smallest genetic distance (0.0628), which reflects that they have the closest genetic relationship. The genetic distance between the Chinese yellow quail and the Korean quail is 0.0951. Therefore, the Chinese black quail and the Korean quail are clustered together firstly, and then the Chinese yellow quail.

Development and Application of Est-Ssr Markers in Quails

Aiming at accelerating the application of molecular markers in the genetic improvement of quails, six EST-SSR markers were successfully developed using a bioinformatics method. Polymorphisms of three quail populations (Chinese yellow quail, China black quail and Korean quail) were detected. The results showed that there were 2-6 alleles in six EST-SSR markers. Mean polymorphism information contents of Chinese yellow quails, Chinese black quails and Korean quails were determined as 0.5451, 0.4962 and 0.4937, respectively. Average heterozygosity valuesof 0.6134, 0.5759 and 0.5613 were calculated. Among the six EST-SSR markers, three were highly polymorphic, and the other three were moderately polymorphic. The newly-developed six EST-SSR markers may be used to determine the genetic diversity of quails. The six EST-SSR markers identified were related to carbohydrate metabolism and melanin synthesis, but their specific mechanisms need to be further analyzed.

Immunohistochemical localization of vasoactive intestinal peptide in bursa of fabricius of Chinese yellow quail

This study aimed to reveal the distribution and morphological characteristics of vasoactive intestinal peptide (VIP) at different ages in the bursa of Fabricius (BF) in Chinese Yellow Quail. The distribution and morphological characteristics of VIP of BF in Chinese yellow quails at different ages (0, 1, 3, 5, 9, 13, 17, 21, 25, 29, 32 and 36 weeks) were observed using the immunohistochemical streptavidin-biotin complex method after obtaining the sections and subsequent immunohistochemical staining. Then semi-quantitative analysis of the mean optical density (MOD), integral optical density (IOD) and mean gray value (MGV) for VIP immunoreactivity was performed through Image-Pro Plus 6.0 software. VIP was observed at all ages in Chinese yellow quail’s BF. It formed a long fusiform, oval or granular type structures with clear outline mainly localized in the submucosa, muscular layer and serosal connective tissue. At 25 weeks of age, the MOD value of VIP-positive cells reached the maximum, and then gradually reduced, while the MGV value was the lowest. We observed the localization and morphological characteristics of VIP in BF of Chinese yellow quail. VIP was mainly localized in the submucosa, muscular layer and serosal connective tissue of BF. Findings of this study may provide further understanding of the function of VIP in BF of Chinese yellow quails.

Two novel linkage SNPs of VLDLR gene intron 11 are associated with laying traits in two quail populations

Abstract. The very low density lipoprotein receptor (VLDLR) is an important multifunctional receptor and plays a key role in chicken reproduction. This study is designed to investigate the effect of variants in the VLDLR gene on quail laying traits. Two quail populations were studied – yellow feather quail and chestnut feather quail; 384 individuals per breed were used. The laying traits (the weight of the first egg, the age of the first egg, egg weight, the weight of 20-week-old and the egg number of 20-week-old) were measured and recorded. The polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) method was developed to genotype those individuals. The results showed two novel polymorphisms, i.e. two linkage variations in intron 11 of the VLDLR gene (363T &gt; C and 392C &gt; T). They are associated with the weight of the first egg, the age of the first egg and egg number of 20-week-old in yellow feather and chestnut feather quail. The two variations in intron 11 of VLDLR may be linked with potential major loci or genes affecting some laying traits.

Characterization of Japanese Quail yellow as a Genomic Deletion Upstream of the Avian Homolog of the Mammalian ASIP (agouti) Gene

ASIP is an important pigmentation gene responsible for dorsoventral and hair-cycle-specific melanin-based color patterning in mammals. We report some of the first evidence that the avian ASIP gene has a role in pigmentation. We have characterized the genetic basis of the homozygous lethal Japanese quail yellow mutation as a >90-kb deletion upstream of ASIP. This deletion encompasses almost the entire coding sequence of two upstream loci, RALY and EIF2B, and places ASIP expression under control of the RALY promoter, leading to the presence of a novel transcript. ASIP mRNA expression was upregulated in many tissues in yellow compared to wild type but was not universal, and consistent differences were not observed among skins of yellow and wild-type quail. In a microarray analysis on developing feather buds, the locus with the largest downregulation in yellow quail was SLC24A5, implying that it is regulated by ASIP. Finally, we document the presence of ventral skin-specific isoforms of ASIP mRNA in both wild-type quails and chickens. Overall, there are remarkable similarities between yellow in quail and lethal yellow in mouse, which involve a deletion in a similar genomic position. The presence of ventral-specific ASIP expression in birds shows that this feature is conserved across vertebrates.

Effects of the Dominant Lethal Yellow Mutation on Reproduction, Growth, Feed Consumption, Body Temperature, and Body Composition of the Japanese Quail

Wild-type Japanese quail were compared with full-sibs with a yellow plumage color determined by an autosomal dominant mutation (Y), which is lethal when homozygous. These quail have wheat-straw yellow-colored feathers. Early growth was slower in yellow quail that had 2.4% lower BW than wild-type quail (149.3 g vs. 153.0 g) at 28 d of age. The BW, however, was similar for yellow and wild-type males at 35 d, and it remained so throughout the last part of the growth of the quail monitored until the age of 120 d, as indicated by the very close parameters of the monomolecular growth curve [BW= A - B exp(-kt)] obtained for the 2 groups. Yellow plumage color was also associated with a more difficult adaptation to housing (measured by temporary BW loss) in individual cages and to a significantly 0.2 degrees C lower body temperature at 42 d, but feed consumption and residual feed intake were similar for the 2 plumage color phenotypes. Breast and liver weights were similar in the 2 groups, but abdominal fat was 24% higher (4.66 vs. 3.76 g) in yellow quail. There is some association between the correlated effects of the Y gene in quail and those of the lethal mutation A(y) at the agouti locus in the mouse.