TYR (Tyrosinase) and TYRP1 (Tyrosinase-related protein 1) play crucial roles in determining the coat color of birds. In this paper, we aimed to characterize the relationship of TYR and TYRP1 genes with plumage colors in Korean quails. The SNPs were searched by cDNA sequencing and PCR-SSCP in three plumage color Korean quails (maroon, white and black plumage). Two SNPs (367T→C and 1153C→T) were found in the coding region of TYRP1 gene, but had no significant association with plumage phenotype in Korean quails. The expression of TYR was higher in black plumage quails than that in maroon plumage quails. In contrast, the expression of TYRP1 was lower in black plumage quails than that in maroon plumage quails. This study suggested that the melanic plumage color in Korean quails may be associated with either increased production of TYR or decreased production of TYRP1.

1. The relationship of polymorphisms in the Melanocortin 1 Receptor (MC1R) and Agouti Signalling Protein (ASIP) genes with plumage colour in Japanese quail was investigated by cloning and sequencing the entire coding regions from black, white and maroon Japanese quail embryos at 12 d of incubation. 2. Three SNPs were identified in the MC1R coding region by multiple alignment of sequences from individuals with different plumage colours. A missense C/T mutation located at 169 bp within the Open Reading Frame caused a Ile57Val mutation in the amino acid sequence, and had a significant relationship with the black colour. 3. The expression of MC1R was higher in black plumage quails than that in maroon plumage quails, whereas the expression of ASIP was higher in maroon plumage quails than that in black plumage quails. 4. It is concluded that the black plumage colour in Japanese quails may be caused by either increased production of MC1R or decreased production of ASIP.

The Japanese quail expresses polymorphism in plumage colors, including black, yellow, white, wild-type (maroon), and various intermediate colors through hybridization of quail with different plumage colors. The expression levels of MC1R and ASIP play important roles in the regulation of plumage colors in birds. In this study, the eukaryotic expression vector of pcDNA 3.1 + was used to analyze the effects of forced expression of MC1R and ASIP on the plumage colors of Japanese quail embryos. The constructed eukaryotic expression vectors of pcDNA 3.1 (+)-MC1R and pcDNA 3.1(+)-ASIP were transfected into wild-type Japanese quail embryos by Lipofectamine TM 2000 liposome at 6 days of incubation. After 3 days, the embryos were collected to analyze the plumage colors and the expression levels of MC1R, ASIP, and DCT genes in skin tissue. Forced expression of the MC1R gene by transfection of the pcDNA 3.1(+)-MC1R vector led to hyperpigmentation (similar to black plumage), whereas forced expression of the ASIP gene by transfection of the pcDNA 3.1(+)-ASIP vector led to hypopigmentation (similar to white plumage) in wild-type quail embryos. Two kinds of ASIP alternative splicing (ASIP1 and ASIP2) were found in Japanese quail, which did not have a significant effect on the plumage color or the main motifs of the ASIP protein. This study indicated that the black plumage color may be caused by increased production of MC1R and the white plumage color may be caused by increased production of ASIP in Japanese quail.

In this study, the SWKQ series microcomputer automatic incubator was used to study the growth and development of quail in the embryonic stage. Results showed that the embryo shape of became gradually defined as embryo aged. On day 6, the head and body of quail were clearly differentiated, the legs became longer and the wings appeared. At 7 embryo age, the entire embryo of quail was very clear, and the beak has formed. During 3 to 9 days of age, quail embryos length increased quickly, showing a linearly upward trend. At 9 day old, quail embryos length reached 2.2 cm. The regression equation of embryo length to day old was curve regression, giving as following: y=-0.464+0.325x-0.004x 2 , y: embryo length, x: the age of the embryo.

In this study, six microsatellite markers were adopted to detect the genetic diversity and analyze the genetic distance of three Chinese indigenous sheep breeds. The results showed that 161 alleles were detected in the three breeds of sheep populations, and the average effective number of alleles, the average polymorphism information content (PIC) of six microsatellite markers in fat-tailed sheep, small tailed han-sheep, Yuxi fat-tailed sheep were 5.8844, 6.3103, 4.8017 and 0.7463, 0.7790, 0.7140 respectively. Five markers were highly polymorphic except marker ILSTS011 which gave moderate polymorphic. Except markers OarFCB48, OarFCB304 and BL1038, the other three microsatellite markers deviated significantly from the Hardy-Weinberg Equilibrium (P<0.01) in the three breeds of sheep populations. The genetic differentiation coefficient of each locus ranged from 0.0059 to 0.1159, with an average of 0.0482, indicating a 4.82% gene variation among different populations. So the degree of differentiation among populations was low. The small tailed han-sheep and fat-tailed sheep with minimum genetic distance (0.2163) were first clustered as a group, then they clustered with Yuxi fat-tailed sheep.

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.

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.

Genetic diversity of four quail populations, including Korean quails (maroon quails), Peking white quails, Chinese yellow quails and Chinese black quails, were analyzed by microsatellite markers, aiming to provide scientific basis for new breeds of Chinese black quails for egg production as well as the assessment, protection and utilization of Chinese quail’s genetic resources. The results showed that 48 alleles were detected by nine microsatellite markers in the four quail populations, with the mean of 5.33 alleles in each locus. The average effective number of alleles marked by the nine microsatellite markers in Chinese black quails, Peking white quails, Chinese yellow quails and maroon quails were 3.5338, 3.6135, 4.0312 and 3.6508 respectively. The average heterozygosity of the four quail populations were 0.6952, 0.7046, 0.7353 and 0.7096 respectively. The average polymorphic information content of nine microsatellite loci in four quail populations were 0.6204, 0.6587, 0.6942 and 0.6639, respectively, all of which were greater than 0.5, indicating the four populations’ copious genetic diversity. In this study, the average genetic differentiation coefficient among populations was 0.0349, so the genetic variation among populations accounted for 3.49%, which demonstrated that genetic variation among populations was just a small proportion of the total population genetic variation, and there was little differentiation among the four populations. Cluster analysis indicated that Chinese black quails and Peking white quails were firstly clustered, and then Chinese yellow quails and maroon quails were clustered, and finally the two were clustered together.