Chinese Native Chicken Research Articles

Tissue-specific expression of the chicken adipose differentiation-related protein (ADP) gene

Adipose differentiation-related protein gene (ADP) plays an important role in controlling lipid accumulation in mammals. It may also affect lipid deposition in birds. However, the molecular mechanism of its actions in birds remains unknown. In the present study, the coding sequence of ADP cDNA for Chinese native breed Sichuan Mountainous Black-bone chicken (MB) was first cloned from abdominal fat using reverse transcription-PCR (RT-PCR). This putative MB ADP cDNA (1,881 bp) encodes an open reading frame of 438 amino acids (AA) and shares high AA sequence identity with that of red jungle fowl (99%), duck (92%), house mouse (70%), human (70%), chimpanzee (70%), pig (70%), domestic cow (69%) and domestic sheep (68%). Further analysis using bioinformatics shows the deduced MB ADP protein has the typical characters of PAT (Perilipin, Adipophilin and Tip47) family. Quantitative real-time PCR (qRT-PCR) analysis revealed that ADP expresses in chicken leg muscle, whole brain, heart, liver, pectoralis muscle, abdominal fat and subcutaneous fat. Ontogenetic expression studies shows ADP expression levels in abdominal fat, subcutaneous fat and pectoralis muscle were prior to that in leg muscles at posthatch day (P) 84. But, its levels in abdominal fat and subcutaneous fat were less than that in leg muscles at P28, 42, 56 and 70, respectively. The ADP expression levels in subcutaneous fat and abdominal fat were stable from P28 to P70 and both were less than their counterparts at P84. However, it changed greatly in pectoralis muscle, liver, brain, heart and leg muscle at all points. Patterns of ADP expression suggest that ADP plays an important role in fat development, but further study is needed to reconfirm its function in a large population and in other breeds with different genetic backgrounds.

New alleles of chicken CD8α and CD3d found in Chinese native and western breeds

Chinese native chicken breeds provide useful resources for the study of genetic diversity. In this study, the alleles of CD8α and CD3d cDNA from Chinese native and introduced western breeds of chicken were analyzed at the sequence level. Six alleles were found, due to 13 amino acid replacements in the extracellular domain of the CD8α sequence. There were four alleles detected in the Chinese strains, and alleles 5 and 6 were identified for the first time. Allele 6 was shared by Langshan, Beijing Fatty and Recessive White Feather chickens. Allele 2, found in the Bigbone strain, was the same as that found in the Leghorn strain H.B15.H7, and allele 3 in the Xianju breed was also the same as in the Leghorn strain H.B15.H12. Two Leghorn lines (RPL line 7 and AY519197) and the Camellia possessed an allele (alleles 1, 4 and 5), respectively, that was not found in the other lines. Nine out of 13 amino acid replacements were situated in the putative major histocompatibility complex (MHC) class I binding CDR1 (positions 30, 33 and 34), CDR2 (positions 58, 62, 63 and 65) and CDR3 (positions 90 and 106). Except for the Xianju breed, the CD8α cDNA of Chinese native chicken breeds shared high homology. Two alleles were found in CD3d. Three additional nucleotides were found at positions 64, 65 and 66 in the newly discovered allele 2. This led to a difference of four amino acids (at residues 22, 23, 24 and 25) in the extracellular domain of CD3d cDNA from the Gushi, Recessive White Feather and ISA chickens compared with these of the White Leghorn and T11.15 ( NM_205512). Five hybridoma clones (1C9, 1H5, 4B11, 6G5 and 13C5) against chicken CD8α were generated by DNA immunization. Two monoclonal antibodies (mAbs), 6G5 and 4B11, showed reactivity to the splenocytes from five Chinese native chicken breeds, the Recessive White Feather chicken and the Leghorn ( AY519197), while mAbs 1C9, 1H5 and 13C5 showed no reaction with these breeds.

Analysis of mtDNA sequences shows Japanese native chickens have multiple origins

In this study, we analysed the mitochondrial DNA D-loop region of Japanese native chickens to clarify their phylogenetic relationships, possible maternal origin and routes of introduction into Japan. Seven haplogroups (Types A-G) were identified. Types A-C were observed in Jidori, Shokoku and related breeds. However, Type C was absent in Shokoku, which was introduced from China, while most Indonesian native chickens were included in the Type C haplogroup. Types D-G were observed in Shamo and related breeds. Type E had a close genetic relationship with Chinese native chickens. Our results indicate that some breeds were not introduced into Japan as suggested in conventional literature, based on low nucleotide diversity of certain chicken breeds. Sequences originating from China and Korea could be clearly distinguished from those originating from Southeast Asia. In each group, domestic chickens were divided into the Jidori-Shokoku and Shamo groups. These results indicate that Chinese and Korean chickens were derived from Southeast Asia. Following the domestication of red junglefowl, a non-game type chicken was developed, and it spread to China. A game type chicken was developed in each area. Both non-game and game chickens formed the foundation of Japanese native chickens.

Development of breast muscle and meat quality in Arbor Acres broilers, Jingxing 100 crossbred chickens and Beijing fatty chickens

The objective of this experiment was to examine development of breast muscle and myofiber of M. pectoralis superficialis in three chicken breeds. Commercial broiler chickens (Arbor Acres broilers, AA), crossbred chickens (Jingxing 100 crossbred chickens, JXC) and Chinese native chickens (Beijing fatty chickens, BJF) were grown up to 98 d to estimate myofiber density, and size (area, and diameter of myofibers) in P. superficialis. At 42, 56, 70, 84, and 98 d of age, Pectoralis muscle was used to evaluate breast muscle weight, breast yield, and tenderness (shear force value). Results indicate that commercial broilers have higher breast weight, and higher shear force value than crossbred chickens and Chinese native chickens, that may be due to an increased myofiber diameter and area in Pectoralis muscle. It is suggested that histological properties of myofibers play an important role in increasing the shear force value of meat.

Characterization of Genetic Polymorphism of Novel MHC B-LB II Alleles in Chinese Indigenous Chickens

Genetic polymorphism of the major histocompatibility complex (MHC) B-LB II gene was studied by amplification of exon 2 using PCR, followed by cloning and DNA sequencing in eight indigenous Chinese chicken populations. To reveal the genetic variation of the B-LB II gene, 37 types of patterns detected by PCR-SSCP were investigated first, which would be used to screen novel B-LB II sequences within the breeds. The types of PCR-SSCP patterns and final sequencing allowed for the identification of 31 novel MHC B-LB II alleles from 30 unrelated individuals of Chinese chickens that were sampled. These are the first designators for the alleles of chicken MHC B-LB II gene based on the rule of assignment for novel mammalian alleles. Sequence alignment of the 31 B-LB II alleles revealed a total of 68 variable sites in the fragment of exon 2, of which 51 parsimony informative and 17 singleton variable sites were observed. Among the polymorphic sites, the nucleotide substitutions in the first and second positions of the codons accounted for 36.76% and 35.29%, respectively. The sequence similarities between the alleles were estimated to be 90.6%–99.5%. The relative frequencies of synonymous and nonsynonymous nucleotide substitutions within the region were 2.92%±0.94% and 14.64%±2.67%, respectively. These results indicated that the genetic variation within exon 2 appeared to have largely arisen by gene recombination and balancing selection. Alignment of the deduced amino acid sequences of the β1 domain coded by exon 2 revealed 6 synonymous mutations and 27 nonsynonymous substitutions at the 33 disparate sites. In particular, the nonsynonymous substitutions at the putative peptide-binding sites are considered to be associated with immunological specificity of MHC B-LB II molecule in Chinese native chickens. These results can provide a molecular biological basis for the study of disease resistance in chicken breeding.

Correlations between Heterozygosity at Microsatellite Loci, Mean d2 and Body Weight in a Chinese Native Chicken

A total of two hundred twenty eight half-sib chickens were scored for allele size at 20 microsatellite loci to estimate individual heterozygosity and mean d 2 . The averages of microsatellite heterozygosity, allele per locus and mean d 2 were 0.39, 3.6 and 49, respectively. The body weight was measured biweekly from birth to twelve weeks of age. Gompertz function was assumed to simulate body weight and to estimate the growth model parameters. Due to sex effect on body weight, the regression of body weight on heterozygosity as well as on mean d 2 in males and females was analyzed separately in the present study. Positive correlations were found between microsatellite heterozygosity and body weight in males and females (p<0.05). Positive correlation also observed between individual heterozygosity and simulated maximum daily gain estimated from Gompertz function in female chickens (p<0.05). There were no significant correlations between mean d 2 and body weight. The results suggest that local effect hypothesis could explain the correlations between heterozygosity and fitness-related traits in the domesticated chicken population, rather than the general effect hypothesis does.

Skewed allele frequencies of an Mx gene mutation with potential resistance to avian influenza virus in different chicken populations

The Mx gene is considered to confer positive antiviral responses to the orthomyxovirus in many organisms. In the chicken, 1 nonsynonymous single nucleotide polymorphism (G to A) at position 2,032 of Mx cDNA was demonstrated to confer positive antiviral activity in vitro to avian influenza virus in a previous study. In the current study, 15 Chinese native chicken breeds, 4 highly selected commercial lines, and the Red Jungle Fowl were selected to detect allele frequencies of the Mx mutation. The frequencies of the favorable allele A in native breeds were 0.7241 to 0.9554, which were much higher than those (0.0565 to 0.2742) found in the commercial populations. Whereas most native breeds were in Hardy-Weinberg equilibrium at this locus (P > 0.01), 3 out of 4 commercial populations were not in Hardy-Weinberg equilibrium (P < 0.01). Selection, environment, and negative correlations between production and disease resistant traits could contribute to highly skewed frequencies of the mutation among native breeds and commercial populations. The results suggested that further studies are needed with regard to the genetic resistance to avian influenza in different populations with various domestication background and selection history.

Association of Single Nucleotide Polymorphisms of the Insulin Gene with Chicken Early Growth and Fat Deposition

Growth rate, body composition, and fat deposition are important traits in chickens. Insulin plays important roles in hepatic cells, muscle cells, and adipose tissue cells. The purpose of the present study was to analyze association of the insulin (INS) gene with chicken growth and body composition traits. Using a F2 design resource population constructed with the crossing of Chinese native Xinghua chickens and White Recessive Rock chickens, the association of 4 single nucleotide polymorphisms (SNP; A+428G, C+1549T, T+3737C, and A+3971G) of INS gene with 13 growth and body composition traits was studied. The T+3737C genotypes were significantly associated with small intestine length (P = 0.0002), and the A+3971G genotypes were significantly associated with early growth (hatch weight and BW at 28 d of age) (P < 0.0001), breast angle (P = 0.0002), and small intestine length (P < 0.0001). None of the 4 SNP was significantly associated with abdominal fat pad weight (P > 0.05). The haplotypes based on the 4 SNP were also significantly associated with early growth (hatch weight and BW at 28 d of age; P < 0.0001) and breast angle (P < 0.0001) but not with small intestine length (P = 0.0505). These results suggested that variation of the insulin gene was significantly associated with chicken early growth but not with fat deposition. In addition, the data from the present study supported the inference that both the one-SNP-at-a-time and the haplotype-based approaches have their own advantages and disadvantages when association analysis of one SNP and haplotypes with chicken complex traits was conducted.

Cluster Analysis of 12 Chinese Native Chicken Populations Using Microsatellite Markers

The genomes of Chinese native chicken populations were screened using microsatellites as molecular markers. A total of, 528 individuals comprisede12 Chinese native chicken populations were typed for 7 microsatellite markers covering 5 linkage groups and genetic variations and genetic distances were also determined. In the 7 microsatellite loci, the number of alleles ranged from 2 to 7 per locus and the mean number of alleles was 4.6 per locus. By using fuzzy cluster, 12 Chinese native chicken populations were divided into three clusters. The first cluster comprised Taihe Silkies, Henan Game Chicken, Langshan Chicken, Dagu Chicken, Xiaoshan Chicken, Beijing Fatty Chicken and Luyuan Chicken. The second cluster included Chahua Chicken, Tibetan Chicken, Xianju Chicken and Baier Chicken. Gushi Chicken formed a separate cluster and demonstrated a long distance when comparing with other chicken populations. (Asian-Aust. J. Anim. Sci. 2004. Vol 17, No. 8 : 1047-1052)

Polymorphism of Insulin-like Growth Factor I Gene in Six Chicken Breeds and Its Relationship with Growth Traits

The polymorphism of insulin-like growth factor I (IGF I) in 6 chicken breeds (total n=515) was detected by PCR-Pst I- RFLP, and allele A (621 bp) or allele B (364 and 257 bp) were observed. In these chicken breeds, it was found that exotic chicken carried high frequencies of allele B, while Chinese native chicken breeds carried high frequencies of allele A. Meanwhile the role of IGF I was investigated in 133 Ningdu Yellow chicken and 162 Wanzhai Yellow chicken. Five growth traits were recorded for analyzing the association between IGFI gene polymorphism and performance. In both the Ningdu and Wanzhai Yellow breeds, body weight at 4 months was significantly higher with BB genotype than with AA genotype (p<0.05). Furthermore, body weight at 2 months in the Wanzhai Yellow breeds was also higher with BB genotype than with AA genotype (p<0.05). There were no differences among the genotypes for the other traits studied. Based on these results, it is necessary to do more studies on IGFI before making the IGFI locus into the application of maker-assisted selection programms. (Asian-Aust. J. Anim. Sci. 2004. Vol 17, No. 3 : 301-304)

Genetic Variability of mtDNA Sequences in Chinese Native Chicken Breeds

The variability of mtDNA hypervariable segment I (HVS I) sequences was investigated in a total of 48 birds belonging to 12 Chinese native chicken breeds. Sixteen haplotypes were identified from 35 polymorphic nucleotide sites which accounted for 6.4% of a sequenced 544 bp fragment. Diversity analysis of the haplotypes showed that Tibetan, Langshan and Henan cockfight chicken had only one haplotype, while ancient haplotypes existed in Taihe silky and Chahua chicken. Phylogenetic analysis of the haplotypes suggested that Chinese native chicken breeds shared 5 maternal lineages and some breeds would share the same maternal lineage, regardless of their external features and ecological types. Both divergent and phylogenetic analysis of the haplotypes indicated the close genetic relationships between the Chinese native chicken breeds and G. g. gallus and G. g. spadiceus from different areas, which implied that G. g. gallus and G. g. spadiceus were the original ancestors of the Chinese native chicken breeds. (Asian-Aust. J. Anim. Sci. 2004. Vol 17, No. 7 : 903-909)

Analysis of genetic variation of Chinese native chicken breeds using microsatellite markers

Analysis of genetic variation of Chinese native chicken breeds using microsatellite markers

Genetic diversity of Chinese native chicken breeds based on protein polymorphism, randomly amplified polymorphic DNA, and microsatellite polymorphism

Genetic diversity of Chinese native chicken breeds was investigated using protein polymorphism, randomly amplified polymorphic DNA (RAPD), and microsatellite polymorphism. Imported broiler and layer breeds were also included in the analysis. The results from protein polymorphism did not show distinct differences between Chinese native chicken and imported broilers; however, there were small significant differences between these two types of chickens. The results from RAPD indicated that gene diversity within a population was large in Chinese native chickens, intermediate in broilers, and low in layers and that there were small differences between Chinese native chickens and both broilers and layers. A great difference between broilers and layers was observed. Microsatellite polymorphism data showed that genetic diversity was high in the Chinese native chickens and low in layers and that there was a close relationship between Chinese native chickens and broiler but a remote relationship between Chinese native chickens and layers. The wide genetic diversity of Chinese native breeds can meet different requirements of breeding for chicken quality in China.

Comparative analysis of allozyme, random amplified polymorphic DNA, and microsatellite polymorphism on Chinese native chickens

Allozyme, random amplified polymorphic DNA (RAPD), and microsatellite polymorphisms were examined and compared among five native populations of Chinese chickens, two fast-growing broiler lines, and one layer line. Three assay systems resulted in a different average heterozygosity or gene diversity in each of the eight populations. The lowest average heterozygosity was obtained with allozyme analysis (0.2209), intermediate heterozygosity was obtained with RAPD (0.2632), and the highest heterozygosity was observed with microsatellite analysis (0.7591). The genetic distances among all populations measured by three methods were also different. Allozyme data showed close relationships between Chinese native chickens and the two broiler lines, but they were both remotely related to the layer line. Microsatellite polymorphism analysis was similar to the allozyme analysis but genetic distances from RAPD showed a close relationship between Chinese native chickens and broiler and layer chickens.

New variations in intron 4 of growth hormone gene in Chinese native chickens.

Polymorphism in intron 4 of chicken growth hormone (cGH) gene was studied in 20 Chinese native chicken populations and broiler or layer populations. A total of eight restriction digestion profiles were identified in intron 4 and confirmed by sequencing. Among 20 populations, there were distinctively different allele numbers and frequencies of intron 4 restriction fragment length polymorphisms (RFLPs) between Chinese native chickens and broilers or layers. Two new alleles, allele D and allele E, were identified in Taihe Silkies. Allele D was also identified in other Chinese native breeds and a 50 bp fragment deletion was identified in allele E.

The origin and genetic diversity of Chinese native chicken breeds.

The first 539 bases of mitochondrial DNA D-loop region of six Chinese native chicken breeds (Gallus gallus domesticus) were sequenced and compared to those of the red junglefowl (Gallus gallus), the gray junglefowl (Gallus sonneratii), the green junglefowl (Gallus varius) and Lafayette's junglefowl (Gallus lafayettei) reported in GenBank, and the phylogenetic trees for the chickens were constructed based on the D-loop sequences. The results showed that the four species of the genus Gallus had great differences among each other the G. g. domesticus was closest to the red junglefowl in Thailand and its adjacent regions, suggesting the Chinese domestic fowl probably originatedfrom the red junglefowl in these regions. The two subspecies of Thailand, G. g. gallus and G. g. spadiceus, should belong to one subspecies because of their resemblance. In the case of native breeds, there existed a great difference between the egg breeds and general purpose breeds, which suggested different maternal origins of the two types.

Effect of hybridization on carcass traits and meat quality of erlang mountainous chickens.

Native chickens hold a significant share of the market in China. In response to the huge demand from the market, the productivity of Chinese native chickens needs to be improved. Cross breeding is an effective method to increase productivity, although it might affect meat quality. In this study, two pure lines (SD02 and SD03) of Erlang mountainous chickens were hybridized with a yellow feather and faster growing line (SD01). The effect of hybridization on carcass and meat quality (physiochemical and textural traits) was measured in the F1 population at d 91 of age. The hybrids exhibited higher body weight and dressed weight, and amount of semi-eviscerated, eviscerated, breast muscle and abdominal fat (p<0.05). Abdominal fat yield also increased (p<0.05) compared to the offspring of the two pure-lines. Meanwhile, there was no significant difference in meat quality traits except for the myofiber diameter and density and the shear force of the breast muscle. Overall, the offspring of cross-lines were similar to pure lines in meat color, pH value, inosinic acid, crude protein, crude fat, dry matter, moisture content and amino acid composition in the breast muscle. These results suggest that productivity can be improved via cross-breeding while maintaining meat quality of the Erlang mountainous chicken.