Age-related declines in ejaculate quality and sperm kinematics vary among strains of Japanese Quail (Coturnix japonica).

For successful breeding programs, it is important to quantify the useful period of a male's reproductive life and it is often done simply by measurement of semen quality. This information is lacking for Japanese quail so we tested whether there is a decline in ejaculate quality and sperm kinematics with age, and whether the decline varies among strains. Nine males (n = 9) from each of 5 strains (A, B, C, D and E) were subjected to 4 semen collections (n = 16 per male) at 8, 16, 26 and 36 weeks of age. Ejaculate volume, sperm concentration and total sperm per ejaculate were measured, and sperm kinematics were analysed using a Sperm Class Analyser (SCA® ). There was a significant effect of age for ejaculate volume, total sperm per ejaculate and per cent medium sperm. The effect of the interaction between age and strain was significant for percent progressive motile sperm, percent rapid sperm, velocity curvilinear, velocity straight line, velocity average path, linearity, straightness and beat cross frequency. Ejaculate volume peaked at Week 26 in all strains, while peak values for sperm concentration and total sperm per ejaculate were observed at Week 16 for most strains. There were declines in percent motile sperm, progressive motile sperm and rapid sperm, and in velocity curvilinear velocity, velocity straight line and velocity average path, by Week 16 for most strains. Linearity declined by Week 26 in some strains, and all strains showed a significant decline in beat cross frequency by that age. In conclusion, the ability of CASA to detect age-related changes in sperm kinematics makes it a valuable tool for identifying the best males and thus improving quail flock fertility. It is essential that breeders understand that age affects both sperm production and sperm kinematics, and that the changes vary with strain.

MC1R polymorphism associated with plumage color variations in Coturnix chinensis.

The melanocortin 1 receptor (MC1R) gene was investigated as a candidate for plumage variations in Chinese painted quail, Coturnix chinensis. Four silent and two missense nucleotide polymorphisms were identified. The correspondent amino acid changes, p.Glu92Lys and p.Pro292Leu, were found in Blue Face and Red Breasted animals respectively. Blue Face is a melanic phenotype similar to the co-dominant Extended Brown of Japanese quail, and both share the p.Glu92Lys mutation. The association of p.Pro292Leu with the recessive Red Breasted was confirmed in 23 animals from an experimental F2 cross.

Coturnicultura como alternativa para aumento de renda do pequeno produtor / Quail production as an alternative to improve income to small farmers

A coturnicultura tem apresentado desenvolvimento significativo nos últimos anos devido às tecnologias empregadas na cadeia produtiva, gerando resultados satisfatórios aos produtores, com baixo custo de investimento. O estudo teve como objetivo avaliar a viabilidade econômico-financeira da coturnicultura para o pequeno produtor rural ou agricultor familiar. Foram utilizados dois grupos com 1.500 aves cada, A1 (aquisição de lote misto com um dia de idade) e A2 (aquisição de fêmeas com 35 dias de idade), e empregados a taxa interna de retorno, o payback simples e o descontado, bem como o valor presente líquido para a análise econômico-financeira. A coturnicultura representa uma alternativa em potencial para agregação de renda ao pequeno produtor/agricultor familiar, pois o retorno do investimento ocorre no segundo ano. Para o início da produção coturnícula, a aquisição de fêmeas aos 35 dias de idade é mais rentável, quando comparada à aquisição de lote misto com um dia de idade. Dessa forma, a alternativa estratégica de comercialização para o início da atividade é o ovo in natura, que possibilita o retorno do investimento em curto prazo.(AU)

Quail production showed significant development in recent years due to technologies used in the production chain, generating satisfactory results for farmers with low cost of investment. The purpose of this study was to evaluate the economic feasibility of quail production implementation for small farmers. A total of 3,000 birds were used and divided in two groups (A1 and A2). The internal rate return was measured, as well as simple payback. The present liquid value for economic and financial analysis was discounted. Quail production is a potential alternative for income increase of small farmers, since the return on investment occurs in the second year. To start quail production, the acquisition of female quails at 35 days of age is more profitable compared to a one day old mixed batch. Thus, the alternative marketing strategy for the beginning of activity is the egg, due to the return on short-term investment.(AU)

Genetic Divergence in Domestic Japanese Quail Inferred from Mitochondrial DNA D-Loop and Microsatellite Markers.

To assess the genetic diversity of domestic Japanese quail (Coturnix japonica) populations, and their genetic relationships, we examined mitochondrial DNA (mtDNA) D-loop sequences and microsatellite markers for 19 Japanese quail populations. The populations included nine laboratory lines established in Japan (LWC, Quv, RWN, WE, AWE, AMRP, rb-TKP, NIES-L, and W), six meat-type quail lines reimported from Western countries (JD, JW, Estonia, NIES-Br, NIES-Fr, and NIES-Hn), one commercial population in Japan, and three wild quail populations collected from three Asian areas. The phylogenetic tree of mtDNA D-loop sequences revealed two distinct haplotype groups, Dloop-Group1 and Dloop-Group2. Dloop-Group1 included a dominant haplotype representing most of the quail populations, including wild quail. Dloop-Group2 was composed of minor haplotypes found in several laboratory lines, two meat-type lines, and a few individuals in commercial and wild quail populations. Taking the breeding histories of domestic populations into consideration, these results suggest that domestic quail populations may have derived from two sources, i.e., domestic populations established before and after World War II in Japan. A discriminant analysis of principal components and a Bayesian clustering analysis with microsatellite markers indicated that the domestic populations are clustered into four genetic groups. The two major groups were Microsat-Group1, which contained WE, and four WE-derived laboratory lines (LWC, Quv, RWN, and AWE), and Microsat-Group2 consisting of NIES-L, JD, JW, Estonia, NIES-Br, NIES-Fr, NIES-Hn, W, and commercial and wild populations. The remaining two lines (AMRP and rb-TKP) were each clustered into a separate clade. This hierarchical genetic difference between domestic quail populations is attributed to the genetic background derived from two different genetic sources-the pre-war and post-war populations-which is well supported by their breeding histories.

Comprehensive Identification of Sexual Dimorphism-Associated Differentially Expressed Genes in Two-Way Factorial Designed RNA-Seq Data on Japanese Quail (Coturnix coturnix japonica).

Japanese quail (Coturnix coturnix japonica) reach sexual maturity earlier, breed rapidly and successfully, and cost less and require less space than other birds raised commercially. Given the value of this species for food production and experimental use, more studies are necessary to determine chromosomal regions and genes associated with gender and breed-differentiation. This study employed Trinity and edgeR for transcriptome analysis of next-generation RNA-seq data, which included 4 tissues obtained from 3 different breeding lines of Japanese quail (random bred control, heavy weight, low weight). Differentially expressed genes shared between female and male tissue contrast groups were analyzed to identify genes related to sexual dimorphism as well as potential novel candidate genes for molecular sexing. Several of the genes identified in the present study as significant sex-related genes have been previously found in avian gene expression analyses (NIPBL, UBAP2), and other genes found differentially expressed in this study and not previously associated with sex-related differences may be considered potential candidates for molecular sexing (TERA, MYP0, PPR17, CASQ2). Additionally, other genes likely associated with neuronal and brain development (CHKA, NYAP), as well as body development and size differentiation (ANKRD26, GRP87) in quail were identified. Expression of homeobox protein regulating genes (HXC4, ISL1) shared between our two sex-related contrast groups (Female Brain vs. Male Brain and Ovary vs. Testis) indicates that these genes may regulate sex-specific anatomical development. Results reveal genetic features of the quail breed and could allow for more effective molecular sexing as well as selective breeding for traits important in commercial production.

Cost-effective development of highly polymorphic microsatellite in Japanese quail facilitated by next-generation sequencing.

Next-generation sequencing technologies permit rapid and cost-effective identification of numerous putative microsatellite loci. Here, from the genome sequences of Japanese quail, we developed microsatellite markers containing dinucleotide repeats and employed these for characterisation of genetic diversity and population structure. A total of 385 individuals from 12 experimental and one wild-derived Japanese quail lines were genotyped with newly developed autosomal markers. The maximum number of alleles, expected heterozygosity and polymorphic information content (PIC) per locus were 10, 0.80 and 0.77 respectively. Approximately half of the markers were highly informative (PIC ≥ 0.50). The mean number of alleles per locus and observed heterozygosity within a line were in the range of 1.3-4.1 and 0.11-0.53 respectively. Compared with the wild-derived line, genetic diversity levels were low in the experimental lines. Genetic differentiation (FST ) between all pairs of the lines ranged from 0.13 to 0.83. Genetic clustering analyses based on multilocus genotypes of individuals showed that most individuals formed clearly defined clusters corresponding to the origins of the lines. These results suggest that Japanese quail experimental lines are highly structured. Microsatellite markers developed in this study may be effective for future genetic studies of Japanese quail.

Índice gonadossomático e correlações entre dimensões e peso testiculares na codorna japonesa (Coturnix coturnix japonica) aos 60 dias de idade / Gonadosomatic index and correlations between testicular dimensions and weight in Japanese quail (Coturnix coturnix japonica) at 60 days old

As dimensões e o peso testicular foram avaliados em 25 machos adultos de codornas japonesas (Coturnix coturnix japonica) e correlacionados entre si, a fim de se buscar obter informações que possibilitem a criação de um parâmetro preditivo da capacidade de produção espermática. As aves foram abatidas e os testículos removidos para mensuração e pesagem. As dimensões e o peso entre os testículos esquerdo e direito foram comparados. Os parâmetros testiculares foram correlacionados entre si por meio da determinação do coeficiente de correlação linear. O índice gonadossomático também foi determinado, indicando alocação de 3,68% do peso corporal em testículos nos machos avaliados, resultado maior do que os descritos na literatura. Apesar da diferença de formato entre os testículos esquerdo e direito, o peso foi semelhante, sugerindo que não há diferença na capacidade de produção espermática entre eles. Diferença estatística entre os valores biométricos indica que o testículo esquerdo é mais curto e mais arredondado, enquanto o direito é mais longo e estreito. O peso corporal apresentou baixa correlação com o peso testicular, 0,14 e 0,12 para os testículos esquerdo e direito, respectivamente. Os parâmetros que melhor se correlacionaram com o peso testicular foram a largura e a espessura. Considerando-se a identificação de um parâmetro único para comparação entre machos, a espessura do testículo esquerdo apresentou coeficiente de correlação linear de 0,89 com o somatório do peso dos dois testículos. Com base nessa informação, métodos não invasivos, como a ultrassonografia, poderiam ser utilizados para estimar o potencial reprodutivo e auxiliar na comparação de machos de codornas japonesas em núcleos de seleção de aves elite, contribuindo para melhoramento genético da espécie.

The size and testis weight were evaluated and correlated in 25 adult male Japanese quail (Coturnix coturnix japonica), seeking information to enable the development of a predictive parameter of sperm production capacity. The birds were slaughtered and testes removed for measuring and weighing. The size and testis weight were compared between the left and right. The testicular parameters were correlated by determining the linear correlation coefficient. The gonadosomatic index was also determined, indicating the allocation of 3.68% of body weight in the testes, greater than described in literature. Despite the difference in shape between the left and right testis, weight was similar, suggesting that there is no difference in the capacity of sperm production amongst them. A statistical difference between the biometric values indicates that the left testicle is shorter and more rounded, while the right is longer and narrower. Body weight showed a low correlation with the testicular weight, 0.14 and 0.12 for the left and right testes, respectively. The parameters that best correlated with testicular weight were the width and thickness. Given the identification of a single parameter for comparison of males, the thickness of the left testis showed linear correlation coefficient of 0.89 with the sum of the weight of both testicles. From this information, noninvasive methods such as ultrasound could be used to estimate the reproductive potential and ease the comparison of male Japanese quail in elite selection nuclei, contributing to the genetic improvement of the species.

Exigência de treonina digestível para codornas de corte no período de 15 a 35 dias de idade / Digestible threonine requirements for quail meat from 15 to 35 days of age

Estimou-se a exigência de treonina digestível (ThrD) para codornas de corte (Coturnix coturnix sp.) em fase de crescimento no período de 15 a 35 dias de idade. Foram utilizadas 1020 codornas com 15 dias de idade, não sexadas, distribuídas em um delineamento experimental inteiramente ao acaso, com seis porcentagens de adição de treonina digestível - 0,93; 1,00; 1,07; 1,14; 1,21 e 1,28% na dieta - , cinco repetições e 34 codornas por unidade experimental. Não houve efeito sobre o desempenho, o rendimento e a composição química da carcaça e sobre o balanço de nitrogênio com o aumento da porcentagem de treonina digestível na dieta. Houve aumento linear no consumo de treonina e no custo da ração por quilograma de peso vivo ganho com o aumento da porcentagem de treonina digestível. Concluiu-se que o melhor nível de treonina digestível avaliado foi suficiente para atender as exigências de codornas de corte, no período de 15 a 35 dias de idade.

The digestible threonine (DThr) requirements for meat quails (Coturnix coturnix sp) during growing phase from 15 to 35 days of age were estimated, using 1,020 quails with 15 days of age, of both sexes, distributed in a completely randomized design, with six levels of digestible threonine - 0.93; 1.00; 1.07; 1.14; 1.21 and 1.28% in diet, five replications and 34 quails per experimental unit. There was no effect on performance variables, carcass yield and chemical composition and nitrogen balance with the studied increase in digestible threonine levels. There was a linear increase in threonine intake andfeed cost per kilogram of body weight gain with increasing levels of digestible threonine. It was concluded that the best level of threonine evaluated was sufficient to meet the requirements of meat quails, in the period from 15 to 35.

Differential mRNA expression of seven genes involved in cholesterol metabolism and transport in the liver of atherosclerosis-susceptible and -resistant Japanese quail strains.

BACKGROUND: Two atherosclerosis-susceptible and -resistant Japanese quail (Coturnix japonica) strains obtained by divergent selection are commonly used as models to study atherosclerosis, but no genetic characterization of their phenotypic differences has been reported so far. Our objective was to examine possible differences in the expression of genes involved in cholesterol metabolism and transport in the liver between these two strains and to evaluate the value of this model to analyze the gene system affecting cholesterol metabolism and transport. METHODS: A factorial study with both strains (atherosclerosis-susceptible versus atherosclerosis-resistant) and two diets (control versus cholesterol) was carried out. The mRNA concentrations of four genes involved in cholesterol biosynthesis (HMGCR, FDFT1, SQLE and DHCR7) and three genes in cholesterol transport (ABCG5, ABCG8 and APOA1) were assayed using real-time quantitative PCR. Plasma lipids were also assayed. RESULTS: Expression of ABCG5 (control diet) and ABCG8 (regardless of dietary treatment) and expression of HMGCR, FDFT1 and SQLE (regardless of dietary treatment) were significantly higher in the atherosclerosis-resistant than in the atherosclerosis-susceptible strain. Plasma triglyceride and LDL levels, and LDL/HDL ratio were significantly higher in the atherosclerosis-susceptible than in the atherosclerosis-resistant strain fed the cholesterol diet. In the atherosclerosis-susceptible strain, ABCG5 expression regressed significantly and positively on plasma LDL level, whereas DHCR7 and SQLE expression regressed significantly and negatively on plasma triglyceride level. CONCLUSIONS: Our results provide support for the hypothesis that the atherosclerosis-resistant strain metabolizes and excretes cholesterol faster than the atherosclerosis-susceptible strain. We have also demonstrated that these quail strains are a useful model to study cholesterol metabolism and transport in relation with atherosclerosis.

Are farm-reared quails for game restocking really common quails (Coturnix coturnix)?: a genetic approach.

The common quail (Coturnix coturnix) is a popular game species for which restocking with farm-reared individuals is a common practice. In some areas, the number of released quails greatly surpasses the number of wild breeding common quail. However, common quail are difficult to raise in captivity and this casts suspicion about a possible hybrid origin of the farmed individuals from crosses with domestic Japanese quail (C. japonica). In this study we used a panel of autosomal microsatellite markers to characterize the genetic origin of quails reared for hunting purposes in game farms in Spain and of quails from an experimental game farm which was founded with hybrids that have been systematically backcrossed with wild common quails. The genotypes of these quail were compared to those of wild common quail and domestic strains of Japanese quail. Our results show that more than 85% of the game farm birds were not common quail but had domestic Japanese quail ancestry. In the experimental farm a larger proportion of individuals could not be clearly separated from pure common quails. We conclude that the majority of quail sold for restocking purposes were not common quail. Genetic monitoring of individuals raised for restocking is indispensable as the massive release of farm-reared hybrids could represent a severe threat for the long term survival of the native species.

Efeito da influência de probiótico sobre a morfologia intestinal de codornas japonesas / Effect of influence of probiotic on the intestinal morphology of Japanese quail

O presente estudo foi realizado com o objetivo de avaliar a influência da suplementação de probiótico (Bacillus subtilis (3x108 UFC/g), Aspergillus orizae (4x106 UFC/g) e Saccharomyces cerevisae (2x108 UFC/g) sobre a morfologia intestinal de codornas japonesas. Foram utilizadas 400 pintainhas, criadas até 35 dias de idade, em delineamento inteiramente casualizado, com dois tratamentos: controle e probiótico, três repetições/tratamento. Aos sete, 21 e 35 dias de idade foram coletados fragmentos do duodeno das aves para obtenção dos seguintes parâmetros: altura de vilos; profundidade de criptas; número de células caliciformes, e relação vilo/cripta. O probiótico, quando adicionado à dieta, causou no parâmetro profundidade de cripta efeito de interação (probiótico/dia) aos 35 dias de idade, apresentando menor valor. Para altura de vilos e número de células caliciformes, não houve efeito do aditivo, apenas efeito linear (do tempo). Quanto à relação vilo/cripta, não se obteve significância para os tratamentos testados, apenas efeito quadrático em função do tempo.

The present study was to evaluate the influence of supplementation of probiotics (Bacillus subtilis (3x108 UFC/g),Aspergillus oryzae (4x106 UFC/g) and Saccharomyces cerevisiae (2x108 UFC/g) on the intestinal morphology of Japanese quail. 400 chicks were used in place until 35 days of age, in a completely randomized design with 2 treatments: control and probiotic, 3 replicates/treatment. At 07, 21, 35 days old were collected fragments of the duodenum of birds to obtain the following parameters height of villi, depth of crypts, number of goblet cells; relationship villus/crypt. The probiotic in addition to the diet resulted in parameter crypt depth of the interaction effect (probiotic / day) at 35 days of age, showing lower value. For height of villi and number of goblet cells no effect of the additive, only the linear effect (time). In the ratio villus/crypt significance is not obtained for the treatments tested only quadratic effect due to time.

Efeito da interação idade da matriz x peso do ovo sobre o desempenho de codornas de corte / Effect of female breeder age x egg weight interaction on the performance of meat type quails

Avaliou-se a interação idade da matriz versus peso do ovo sobre o desempenho produtivo de codornas de corte (Coturnix coturnix coturnix) no 21º e 42º dias de idade. Em cada classe de idade da matriz, iniciada a partir de 70, 205 e 280 dias, foram incubados 600 ovos, separados em três categorias de peso: categoria 1 - ovos com 11,0-12,9g; categoria 2 - ovos com 13,0-14,9g e categoria 3 - ovos com 15,0-16,9g. Após a eclosão, em cada idade da matriz, foram utilizadas 225 codornas de um dia, de ambos os sexos, provenientes das três categorias de peso, sendo 75 codornas por categoria. O delineamento experimental foi inteiramente ao acaso, e os tratamentos consistiram das três classes de idades da matriz x três categorias de peso do ovo, com cinco repetições de 15 codornas. A dieta experimental foi única para todos os tratamentos com 28 por cento proteína bruta e 2900kcal de energia metabolizável. A categoria peso do ovo e a classe de idade da matriz influenciaram o peso corporal, o ganho de peso e o consumo da dieta no 21º e 42º dias de idade. Codornas oriundas de ovos mais pesados e de matrizes das classes de 205 e 280 dias de idade apresentaram melhor desempenho (P<0,05). A viabilidade foi influenciada pela categoria peso do ovo, ou seja, codornas provenientes de ovos mais leves apresentaram menor viabilidade aos 21º e 42º dias de idade (P<0,05). Ovos mais pesados originaram codornas mais pesadas ao nascimento (P<0,05).

The effect of female breeder age x egg weight interaction was evaluated on the performance of meat type quails (Coturnix coturnix coturnix) at 21st and 42nd days of age. For every female breeder age class (70, 205, and 280 days of age), 600 eggs were classified according to egg weight class (class 1: 11.0-12.9; class 2: 13.0-14.9, and class 3: 15.0-16.9g). A total of 225 quails of both genders, totaling 75 quails for every egg weight class were used in this study. A completely randomized experimental design with five replicates of 15 quails was used. The experimental diets were formulated to contain 28 percent crude protein and 2,900 kcal of metabolizable energy (ME). Weight gain, body weight, feed consumption, and weight gain: feed consumption ratio from hatch to 21st day and from hatch to 42nd day of age were recorded. Both egg weight and female breeder age classes affected body weight, weight gain, and feed consumption at 21st and 42nd days of age. Quails from heavier egg weight class and female breeder age classes 205 and 280 days of age showed higher performance (P<0.05). Quail viability was affected by egg weight class, i.e. quails from lighter eggs showed lower viability at 21st and 42nd days of life. Heavier eggs originated heavier quails at hatch (P<0.05).

Parthenogenesis in unfertilized eggs of Coturnix chinensis, the Chinese painted quail, and the effect of egg clutch position on embryonic development.

Parthenogenesis, embryonic development of an unfertilized egg, was studied for many years in turkeys. In fact, as many as 49% of unfertilized Beltsville Small White turkey eggs develop embryos. However, no research exists on parthenogenesis in quail. The Chinese painted quail is a close relative of the more common Japanese quail and, unlike turkeys or chickens, the small Chinese painted quail reaches sexual maturity rapidly, making it a great candidate for further research on parthenogenesis. Obviously, a better understanding of avian parthenogenesis should increase our knowledge of avian fertilization and early embryonic development. Therefore, we determined if unfertilized Chinese painted quail hens produce embryos. Second, we explored the possibility that position of the egg within the clutch influences parthenogenesis. When initial secondary sexual plumage was apparent at 4 wk of age, male chicks were separated from females to prevent fertilization. Hens were placed in individual cages near sexual maturity, at approximately 6 wk of age. Individual eggs were collected daily and labeled with hen number and date. Eggs were stored for 0 to 3 d at 20 degrees C before incubation at 37.5 degrees C. After 10 d of incubation, approximately 4,000 eggs from 300 laying hens were examined for embryonic development under a magnifying lamp. On average, 4.8% of the unfertilized eggs contained an abortive form of embryonic development consisting of undifferentiated cells and unorganized membranes. Approximately 27% of the laying hens produced at least 1 egg with parthenogenic development. However, about 10% (30) of these hens exhibited a predisposition for parthenogenesis by producing 2 or more unfertilized eggs with embryonic development. Twenty percent of the eggs from 2 hens produced embryonic development. Additionally, the first egg laid in a clutch was most likely to produce embryonic development, with a steady decline in the percentage of eggs with embryonic development as position in the clutch increased. In conclusion, the Chinese painted quail does exhibit parthenogenesis and clutch position influences the rate of naturally occurring parthenogenesis.

Divergent selection for shape of growth curve in Japanese quail. 2. Embryonic development and growth.

1. Embryonic growth and development were analysed using meat type lines of Japanese quail, HG and LG, divergently selected for shape of the growth curve. A total of 1020 embryos of generations 9, 10 or 13 were used for analysis. 2. Considerable inter-line differences were observed in the rate of embryonic development. When compared to HG, LG embryos appeared to be developmentally accelerated during the first 42 h of incubation (larger blastoderm diameter, more somites and higher frequency of more advanced Hamburger-Hamilton stages) as well as at the end of the prenatal period (more embryos with the yolk sac inside the body cavity, shorter incubation period). This corresponded with the trend in postnatal development. 3. Embryonic growth of both lines exhibited an exponential trend. However, considerable inter-line differences were noted in the rate of embryonic growth. Initial growth retardation compensated subsequently by a higher growth rate of HG vs LG quail, characterised the lines after hatching. The same growth pattern repeated three times during the prenatal period (between d 0 and 3, 3 and 8, and 8 and 16). 4. The repeated occurrence of transient decreases in growth rate of the developmentally delayed HG line could be associated with a delayed onset of genetically determined physiological functions mediating utilisation of nutrient supply. 5. Hence, different shapes of growth curves in two genotypes with similar growth potential reveal inter-line differences in physiological age persisting during the whole ontogenesis.

Complete nucleotide sequence of the Coturnix chinensis (blue-breasted quail) mitochondrial genome and a phylogenetic analysis with related species.

Coturnix chinensis (blue-breasted quail) has been classically grouped in Galliformes Phasianidae Coturnix, based on morphologic features and biochemical evidence. Since the blue-breasted quail has the smallest body size among the species of Galliformes, in addition to a short generation time and an excellent reproductive performance, it is a possible model fowl for breeding and physiological studies of the Coturnix japonica (Japanese quail) and Gallus gallus domesticus (chicken), which are classified in the same family as blue-breasted quail. However, since its phylogenetic position in the family Phasianidae has not been determined conclusively, the sequence of the entire blue-breasted quail mitochondria (mt) genome was obtained to provide genetic information for phylogenetic analysis in the present study. The blue-breasted quail mtDNA was found to be a circular DNA of 16,687 base pairs (bp) with the same genomic structure as the mtDNAs of Japanese quail and chicken, though it is smaller than Japanese quail and chicken mtDNAs by 10 bp and 88 bp, respectively. The sequence identity of all mitochondrial genes, including those for 12S and 16S ribosomal RNAs, between blue-breasted quail and Japanese quail ranged from 84.5% to 93.5%; between blue-breasted quail and chicken, sequence identity ranged from 78.0% to 89.6%. In order to obtain information on the phylogenetic position of blue-breasted quail in Galliformes Phasianidae, the 2,184 bp sequence comprising NADH dehydrogenase subunit 2 and cytochrome b genes available for eight species in Galliformes [Japanese quail, chicken, Gallus varius (green junglefowl), Bambusicola thoracica (Chinese bamboo partridge), Pavo cristatus (Indian peafowl), Perdix perdix (gray partridge), Phasianus colchicus (ring-neck pheasant), and Tympanchus phasianellus (sharp-tailed grouse)] together with that of Aythya americana (redhead) were examined using a maximum likelihood (ML) method. The ML analyses on the first/second codon positions, the third codon positions, and amino acid sequence consistently demonstrated that blue-breasted quail and Japanese quail are in the same phylogenetic cluster.

Complete sequence of the Japanese quail (Coturnix japonica) mitochondrial genome and its genetic relationship with related species.

The Japanese quail (Coturnix japonica; JQ) is one of the domesticated fowl species of Japan. To provide DNA sequence information for examination of its phylogenetic position in the order Galliformes, the complete sequence of the JQ mitochondria was determined. Sequence analysis revealed that the JQ mitochondrial genome is a circular DNA of 16 697 basepairs (bp), which is smaller than the chicken mitochondrial DNA of 16 775 bp, but the genomic structure of JQ mitochondria was the same as that of the chicken. The sequence homologies of all mitochondrial genes including those for 12S and 16S ribosomal RNA (rRNA), between Japanese quail and chicken ranged from 78.0 to 89.9%. Because the sequences of NADH dehydrogenase subunit 2 and cytochrome b genes had been reported in five species [Phasianus colchicus (ring-neck pheasant: RP), Gallus gallus domesticus (chicken: CH), Perdix perdix (grey partridge: GP), Bambusicola thoracia (Chinese bamboo partridge: CP), and Aythya americana (redhead: RH)], the concatenated nucleotide sequences (2184 bp) and amino acid sequences of these two genes were used in a phylogenetic analysis of JQ against these five species using a maximum likelihood (ML) method. Using the first and second bases of the codons, and the third base of the codons indicated a phylogenic tree of [RH, (RP, GP), (JQ, (CH, CP))]. A phylogenic tree of [RH, JQ, (RP, GP), (CH, CP)] was determined using amino acid sequences. Because the local bootstrap values for the JQ branch in these trees are not high, additional sequence is necessary for construction of a reliable tree.

Measurement of within and between population genetic variability in quails.

1. To detect polymorphism in various quail lines, Randomly Amplified Polymorphic DNA (RAPD) markers were tested and were found to be effective. 2. Twenty decamer primers were selected at random and tested, and 6 of these generated distinct polymorphic patterns between the quail lines. 3. Out of a total of 60 bands amplified using 6 selected primers, 19 (31.7%) were found to be polymorphic. 4. Genetic similarity within the lines ranged from 0.726 in HBW to 0.836 in KLQ. 5. Genetic similarity estimates between the populations ranged from 0.709 to 0.808.