Comparison of Characteristics and Differences in Early Immune Organ Development in Different Strains of Tianfu Broiler

To effectively develop and utilize high-quality Tianfu broilers, this study evaluated the morphological and structural characteristics of the immune organs of such broilers with different strains (HS1 and HS2) at different developmental stages and analyzed the distribution of mast cells by toluidine blue staining. Moreover, the localization and expression of immunoglobulin, complement C3, C4 and CD3 in immune organs were also detected. The results showed that although there was no significant difference in the development of immune organs in the HS1 and HS2, the number of lymphatic follicles and capsule thickness in the spleen and bursa of Fabricius in HS1 were greater than those in HS2. Additionally, the number of mast cells in the spleen of HS1 was greater at Day 1 and Day 21 and was significantly higher than that of HS2 (p<0.05); the number of mast cells in the bursa of Fabricius reached 9.17 on Day 7, which was significantly higher than that of HS2 (p<0.05). Moreover, the serum IgA and IgM levels in HS1 were higher than those in HS2 on Day 14 and 21 (p<0.05). In addition, the complement C3 content in HS1 was significantly or extremely significantly higher than that in HS2 on Days 1, 14 and 21 (p<0.01, p<0.05), respectively, but significantly lower than in HS2 on Day 7 (p<0.05). These results indicated that the disease resistance of the HS1 line was stronger than that of the HS2 line, which lays a foundation for future disease- resistance breeding of Tianfu broilers.(AU)

Genome-Wide Association Study of Abdominal Fat in Wenshang Barred Chicken Based on the Slaf-Seq Technology

Chicken abdominal fat (AF) is an economically important trait, and many studies have been conducted on genetic selection for AF. However, previous studies have focused on detecting functional chromosome mutations or regions using gene chips. The present study used the specific-locus amplified fragment sequencing (SLAF-seq) technology to perform a genome-wide association study (GWAS) on purebred Wengshang Barred chicken. A total of 1,286,715 single-nucleotide polymorphisms (SNPs) were detected, and 175,211 SNPs were selected as candidate SNPs for genome-wide association analysis using TASSEL general linear models. Two SNPs markers reached genome-wide significance. Of these, rs7943847, rs127627362 were significantly associated with AF at 120 days. These SNPs are close to eight genes (SLC16A6, ARSG, WIPI1, PRKAR1A, FAM20A, ABCA8, ABCA9, CPQ,). These results would enrich the studies on AF and promote the use of Chinese chicken, especially the Wenshang Barred chicken.(AU)

Effect of bone morphogenetic protein 6 (BMP6) on chicken granulose cells proliferation and progesterone synthesis

There is increasing evidence that bone morphogenetic protein 6 (BMP6) plays critical roles in regulating various stages of ovarian follicle development in mammals. However, the mechanisms of regulation of BMP6 in the chicken ovary remain unclear. In this study, mRNA and protein expression level of BMP6 in chicken ovarian follicles at different development stages were determined by qRT-PCR and western blot separately. Different concentrations of BMP6 protein and FSH were added to the culture medium, and the effects to proliferation of granulose cells were detected, further effect on expression pattern of progesterone synthesis associated genes were also analyzed by qRT-PCR and Western blotting and the secretion of progesterone was detected by ELISA. The results showed that mRNA and protein expression level of BMP6 increased significantly in the follicle with the development of follicle (p<0.05) and reached a peak at F1 follicle. Adding concentration of 50ng/ml and 100ng/ml of BMP6 protein promoted significantly the proliferation of granulosa cells (p<0.05), as well as up-regulated the expression of Steroid hormone synthesis acute regulatory protein (StAR) and 3β-hydroxysteroid dehydrogenase (3β-HSD) genes in mRNA and protein level. Meanwhile, the secretion of progesterone was significantly higher in the group that added BMP6 and FSH separately than blank control group (p<0.05) and reached a peak in the group that both added BMP6 and FSH. Collectively, these findings highlight that BMP6 is associated with proliferation of follicular cells and the synthesis of progesterone, which indicated that it took an important role in the follicular development of chicken.(AU)

Effect of bone morphogenetic protein 6 (BMP6) on chicken granulose cells proliferation and progesterone synthesis

There is increasing evidence that bone morphogenetic protein 6 (BMP6) plays critical roles in regulating various stages of ovarian follicle development in mammals. However, the mechanisms of regulation of BMP6 in the chicken ovary remain unclear. In this study, mRNA and protein expression level of BMP6 in chicken ovarian follicles at different development stages were determined by qRT-PCR and western blot separately. Different concentrations of BMP6 protein and FSH were added to the culture medium, and the effects to proliferation of granulose cells were detected, further effect on expression pattern of progesterone synthesis associated genes were also analyzed by qRT-PCR and Western blotting and the secretion of progesterone was detected by ELISA. The results showed that mRNA and protein expression level of BMP6 increased significantly in the follicle with the development of follicle (p<0.05) and reached a peak at F1 follicle. Adding concentration of 50ng/ml and 100ng/ml of BMP6 protein promoted significantly the proliferation of granulosa cells (p<0.05), as well as up-regulated the expression of Steroid hormone synthesis acute regulatory protein (StAR) and 3β-hydroxysteroid dehydrogenase (3β-HSD) genes in mRNA and protein level. Meanwhile, the secretion of progesterone was significantly higher in the group that added BMP6 and FSH separately than blank control group (p<0.05) and reached a peak in the group that both added BMP6 and FSH. Collectively, these findings highlight that BMP6 is associated with proliferation of follicular cells and the synthesis of progesterone, which indicated that it took an important role in the follicular development of chicken.

Detection of Snps in the Melanocortin 1-Receptor (MC1R) and Its Association with Shank Color Trait in Hs Chicken

The melanocortin 1 receptor (MC1R) gene plays a key role in controlling the deposition of melanin. In mammals, the MC1Rgene is regarded as a major candidate gene in the control of melanin formation. In domestic animals, the MC1R gene mainly controls the expression of coat, skin, and plumage color in mammals and birds. In order to breed chickens with dark-green shank faster, we screened the molecular markers for shank color in a HS chicken population by exploring the relationship between polymorphism of the MC1R gene and three different shank colors (light green, dark green and yellow). Two primer pairs for code region of the MC1R gene were designed in the basic of chicken genomic sequence. DNA sequencing was performed to detect the polymorphisms and PCR was used to amplify DNA fragment. Sequences analysis indicated that 7 SNPs were predominant the three HS chicken populations with different shank color, including g.18,287,945C>T, g.18,288,088T>C, g.18,288,150G>A, g.18,288,303A>G, g.18,288,512G>A, g.18,288,513T>C, and g.18,288,520A>C. Association analysis revealed that the dark-green shank population showed moderate polymorphism, whereas the light-green shank population showed low polymorphism among overall 7 SNPs and that SNP6 (g.18,288,513T>C) may be significantly associated with three different shank colors in HS chickens. The haplotype CTGGACA had the largest haplotype frequencies, accounting for 56.22%, and the haplotype combination H1H1 is mainly distributed in the dark-green shank population, and may be used as molecular maker for marker-assisted selection of shank color in HS chickens.(AU)

Detection of Snps in the Melanocortin 1-Receptor (MC1R) and Its Association with Shank Color Trait in Hs Chicken

The melanocortin 1 receptor (MC1R) gene plays a key role in controlling the deposition of melanin. In mammals, the MC1Rgene is regarded as a major candidate gene in the control of melanin formation. In domestic animals, the MC1R gene mainly controls the expression of coat, skin, and plumage color in mammals and birds. In order to breed chickens with dark-green shank faster, we screened the molecular markers for shank color in a HS chicken population by exploring the relationship between polymorphism of the MC1R gene and three different shank colors (light green, dark green and yellow). Two primer pairs for code region of the MC1R gene were designed in the basic of chicken genomic sequence. DNA sequencing was performed to detect the polymorphisms and PCR was used to amplify DNA fragment. Sequences analysis indicated that 7 SNPs were predominant the three HS chicken populations with different shank color, including g.18,287,945C>T, g.18,288,088T>C, g.18,288,150G>A, g.18,288,303A>G, g.18,288,512G>A, g.18,288,513T>C, and g.18,288,520A>C. Association analysis revealed that the dark-green shank population showed moderate polymorphism, whereas the light-green shank population showed low polymorphism among overall 7 SNPs and that SNP6 (g.18,288,513T>C) may be significantly associated with three different shank colors in HS chickens. The haplotype CTGGACA had the largest haplotype frequencies, accounting for 56.22%, and the haplotype combination H1H1 is mainly distributed in the dark-green shank population, and may be used as molecular maker for marker-assisted selection of shank color in HS chickens.

Molecular authentication of meats from three terrestrial birds based on PCR-RFLP analysis of the mitochondrial 12S rRNA gene

In this study, a method utilizing PCR-restriction fragment length polymorphism (PCR-RFLP) of a mitochondrial gene was developed for the identification of chicken (Gallus gallus), quail (Coturnix coturnix), and common pigeon (Columba livia) meat. PCR products of ~440 bp were obtained from the 12S rRNA gene of these three birds using a pair of universal primers. The three terrestrial birds can be distinguished using one restriction endonuclease, Alu I, which was selected based on species-specific variations in the mt 12S rRNA gene sequence using 9 newly-obtained and 44 published chicken, quail and pigeon sequences. This method was also successfully used to identify commercial quail and pigeon meat products, which were found to be adulterated with chicken meat. Additionally, our method had relatively high sensitivity for detecting a meat mixture. Ten percent of chicken meat in the mixed quail and pigeon sample was detectable. This assay can be useful for the accurate identification of meats from terrestrial birds, avoiding mislabeling or fraudulent species substitution in meat products.(AU)

Molecular authentication of meats from three terrestrial birds based on PCR-RFLP analysis of the mitochondrial 12S rRNA gene

In this study, a method utilizing PCR-restriction fragment length polymorphism (PCR-RFLP) of a mitochondrial gene was developed for the identification of chicken (Gallus gallus), quail (Coturnix coturnix), and common pigeon (Columba livia) meat. PCR products of ~440 bp were obtained from the 12S rRNA gene of these three birds using a pair of universal primers. The three terrestrial birds can be distinguished using one restriction endonuclease, Alu I, which was selected based on species-specific variations in the mt 12S rRNA gene sequence using 9 newly-obtained and 44 published chicken, quail and pigeon sequences. This method was also successfully used to identify commercial quail and pigeon meat products, which were found to be adulterated with chicken meat. Additionally, our method had relatively high sensitivity for detecting a meat mixture. Ten percent of chicken meat in the mixed quail and pigeon sample was detectable. This assay can be useful for the accurate identification of meats from terrestrial birds, avoiding mislabeling or fraudulent species substitution in meat products.

Detection of SNPs in the BMP6 Gene and Their Association with Carcass and Bone Traits in Chicken

BMP6, a member of the subfamilies of the morphogenetic proteins (BMPs), plays a crucial role in osteogenic and chondrocyte differentiation in vitro and stimulates chondrogenesis, making chondrocytes differen-tiate on their terminal stage. The objective of this study is to explore the relationship between polymorphism of BMP6 gene and slaughter traits in chicken respectively. We screened the exonic and intronic regions of BMP6 gene by DNA pool construction and amplified DNA fragment by PCR, and finally, we got nine SNPs. Association analysis revealed that BMP6 had no significant association among all slaughter traits in Yellow bantam chicken. However, BMP6 had a significant difference with femur weight, tibia weight, femur length (p 0.05), and was extremely significant with tibia length (p 0.01) in Avian chicken. Moreover, femur perimeter also had significant correlation with BMP6 in Avian chicken. These results provide useful information for further investigation on the function of chicken BMP6 gene.(AU)

Detection of SNPs in the BMP6 Gene and Their Association with Carcass and Bone Traits in Chicken

BMP6, a member of the subfamilies of the morphogenetic proteins (BMPs), plays a crucial role in osteogenic and chondrocyte differentiation in vitro and stimulates chondrogenesis, making chondrocytes differen-tiate on their terminal stage. The objective of this study is to explore the relationship between polymorphism of BMP6 gene and slaughter traits in chicken respectively. We screened the exonic and intronic regions of BMP6 gene by DNA pool construction and amplified DNA fragment by PCR, and finally, we got nine SNPs. Association analysis revealed that BMP6 had no significant association among all slaughter traits in Yellow bantam chicken. However, BMP6 had a significant difference with femur weight, tibia weight, femur length (p 0.05), and was extremely significant with tibia length (p 0.01) in Avian chicken. Moreover, femur perimeter also had significant correlation with BMP6 in Avian chicken. These results provide useful information for further investigation on the function of chicken BMP6 gene.