Identification of quantitative trait loci and candidate genes associated with growth curve parameters in chinese wenshang barred chickens.

The growth curve is a vital instrument for assessing and forecasting weight and developmental shifts in livestock and poultry, which reflects the changes of bodyweight traits with time and plays a key role in guiding breeding and production approaches. This study performed a genome-wide association study (GWAS) for growth curve parameters generated by nonlinear models which fit original weight-age records, to discover the SNPs and candidate genes correlated with growth traits. Data from 362 Chinese Wenshang Barred Chickens weighed at the age of 0, 2, 4, 6, 8, 10, 12, 14, 16, and 18 weeks were used to fit the Gompertz, Logistic, and von Bertalanffy growth models.

Plasma Biochemistry, Intestinal Health, and Transcriptome Analysis Reveal Why Laying Hens Produce Translucent Eggs.

Producing translucent eggs has been found to reduce the quality and safety of the eggs, as well as the demand from consumers. However, the intestinal function and the molecular mechanism for the production of translucent eggs remain uncertain. A total of 120 eggs from 276-day-old Jining Bairi were divided into two groups based on eggshell translucence: the translucent egg group (group T) and the normal group (group C).

Genome-wide association studies of egg production traits by whole genome sequencing of Laiwu Black chicken.

Compared to high-yield commercial laying hens, Chinese indigenous chicken breeds have poor egg laying capacity due to the lack of intensive selection. However, as these breeds have not undergone systematic selection, it is possible that there is a greater abundance of genetic variations related to egg laying traits. In this study, we assessed 5 egg number (EN) traits at different stages of the egg-laying period: EN1 (from the first egg to 23 wk), EN2 (from 23 to 35 wk), EN3 (from 35 to 48 wk), EN4 (from the first egg to 35 wk), and EN5 (from the first egg to 48 wk).

Elucidation of the genetic determination of body weight and size in Chinese local chicken breeds by large-scale genomic analyses.

Background: Body weight and size are important economic traits in chickens. While many growth-related quantitative trait loci (QTLs) and candidate genes have been identified, further research is needed to confirm and characterize these findings. In this study, we investigate genetic and genomic markers associated with chicken body weight and size.

Transcriptome and histological analyses on the uterus of freckle egg laying hens.

Background: In this study, we explored the characteristics and causes of freckle formation. We collected 15 normal and freckled eggs each for eggshell index testing and hypothesized that the structure and function of the uterus would have a direct effect on freckled egg production given that eggshells are formed in the uterus. To test this hypothesis, we collected uterine tissue from laying hens (418 days of age) that laid normal (Group C, n = 13) and freckled (Group T, n = 16) eggs for 7 consecutive days.

Effect of Lactobacillus salivarius SNK-6 on egg quality, intestinal morphology, and cecal microbial community of laying hens.

The objective of this study was to investigate the effect of Lactobacillus salivarius (L. salivarius) SNK-6 supple-mentation on the laying performance, egg quality, blood parameters, intestinal morphology, and cecal microbial community of laying hens. A total of 432 healthy 30-wk-age laying hens were randomly divided into 3 groups with 6 replicates under the same husbandry and dietary regimes: control (CON); 2.

Chicken adaptive response to nutrient density: immune function change revealed by transcriptomic analysis of spleen.

Feed accounts for the largest portion (65-70%) of poultry production costs. The feed formulation is generally improved to efficiently meet the nutritional needs of chickens by reducing the proportion of crude protein (CP) and metabolizable energy (ME) levels in the diet. Although many studies have investigated the production performance during dietary restriction, there is a lack of research on the mechanisms by which immune cell function is altered.

Phage CKT1 Effectively Controls the Vertical Transmission of Pullorum in Adult Broiler Breeders.

Phage therapy is widely being reconsidered as an alternative to antibiotics for the treatment of multidrug-resistant bacterial infections, including salmonellosis caused by . As facultative intracellular parasites, could spread by vertical transmission and pose a great threat to both human and animal health; however, whether phage treatment might provide an optional strategy for controlling bacterial vertical infection remains unknown. Herein, we explored the effect of phage therapy on controlling the vertical transmission of serovar Gallinarum biovar Pullorum ( Pullorum), a poultry pathogen that causes economic losses worldwide due to high mortality and morbidity.

Integrated omics analysis reveals differences in gut microbiota and gut-host metabolite profiles between obese and lean chickens.

Abdominal fat is the major adipose tissue in chickens. In chicken, the deposition of abdominal fat affects meat yield and quality. Previous reports suggest that gut microbiota composition and function are associated with lipid metabolism.

Integrative analysis of circRNA, miRNA, and mRNA profiles to reveal ceRNA regulation in chicken muscle development from the embryonic to post-hatching periods.

Background: The growth and development of skeletal muscle are regulated by protein-coding genes and non-coding RNA. Circular RNA (circRNA) is a type of non-coding RNA involved in a variety of biological processes, especially in post-transcriptional regulation. To better understand the regulatory mechanism of circRNAs during the development of muscle in chicken, we performed RNA-seq with linear RNA depletion for chicken breast muscle in 12 (E 12) and17 (E 17) day embryos, and 1 (D 1), 14 (D 14), 56 (D 56), and 98 (D 98) days post-hatch.

Transcriptome Analysis Reveals the Profile of Long Non-coding RNAs During Chicken Muscle Development.

The developmental complexity of muscle arises from elaborate gene regulation. Long non-coding RNAs (lncRNAs) play critical roles in muscle development through the regulation of transcription and post-transcriptional gene expression. In chickens, previous studies have focused on the lncRNA profile during the embryonic periods, but there are no studies that explore the profile from the embryonic to post-hatching period.

Deciphering the miRNA transcriptome of breast muscle from the embryonic to post-hatching periods in chickens.

Background: miRNAs play critical roles in growth and development. Various studies of chicken muscle development have focused on identifying miRNAs that are important for embryo or adult muscle development. However, little is known about the role of miRNAs in the whole muscle development process from embryonic to post-hatching periods.

Genome-wide association study of body size traits in Wenshang Barred chickens based on the specific-locus amplified fragment sequencing technology.

Chicken body size (BS) is an economically important trait, which has been assessed in many studies for genetic selection. However, previous reports detected 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) of purebred Wenshang Barred chickens.

Transcriptome Analysis of the Chicken Follicular Theca Cells with miR-135a-5p Suppressed.

As a class of transcription regulators, numerous miRNAs have been verified to participate in regulating ovary follicular development in chickens (). Previously we showed that gga-miR-135a-5p has significant differential expression between high and low-yield chicken ovaries, and the abundance of gga-miR-135a-5p is significantly higher in follicular theca cells than in granulosa cells. However, the exact role of gga-miR-135a-5p in chicken follicular theca cells is unclear.

Dynamic Transcriptomic Analysis of Breast Muscle Development From the Embryonic to Post-hatching Periods in Chickens.

Skeletal muscle development and growth are closely associated with efficiency of poultry meat production and its quality. We performed whole transcriptome profiling based on RNA sequencing of breast muscle tissue obtained from Shouguang chickens at embryonic days (E) 12 and 17 to post-hatching days (D) 1, 14, 56, and 98. A total of 9,447 differentially expressed genes (DEGs) were filtered ( < 0.

The high conserved cellular receptors of avian leukosis virus subgroup J in Chinese local chickens contributes to its wide host range.

Avian leukosis virus (ALV) is a tumor-inducing virus that spreads among most chicken species, causing serious financial losses for the poultry industry. Subgroup J avian leukosis virus (ALV-J) is a recombinant exogenous ALV, which shows more extensive host range in comparison with other subgroups, especially in Chinese local chickens. To identify the relationship between ALV-J host range and the polymorphism of its cellular receptors, we performed a wide range epidemiological investigation of current ALV-J infection in Chinese local chickens, and discovered that all the 18 local chicken breeds being investigated from main local chicken breeding provinces were ALV-J positive.

Genome-wide association study of body weight in Wenshang Barred chicken based on the SLAF-seq technology.

Chicken body weight (BW) is an economically important trait, and many studies have been conducted on genetic selection for BW. However, previous studies have detected 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.

Association between BMP15 Gene Polymorphism and Reproduction Traits and Its Tissues Expression Characteristics in Chicken.

BMP15 (Bone morphogenetic protein 15) is an oocyte-secreted growth factor required for ovarian follicle development and ovulation in mammals, but its effects on reproduction in chickens are unclear. In this study, the association between BMP15 polymorphisms and reproduction traits were analyzed, and its expression characteristics in different tissues were explored in LaiWu Black chickens. Three single nucleotide polymorphisms (SNPs) were identified in four hundred LaiWu Black chickens.

[Relationships among immune traits and MHC B-LBII genetic variation in three chicken breeds].

We have assessed the relationships between immune trait (antibody titers of Sheep red blood cell, SRBC; Avian influenza, AI; Newcastle disease, ND) and varieties of MHC B-LBHII Gene in local chicken breeds (Wenshang Barred chicken, LH; Laiwu Black chicken, LWH; and Jining Bairi chicken, BR). We selected 300 chickens randomly from the three indigenous chicken populations. The variations of MHC B-L BII gene were detected by directly DNA sequencing and polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP).

Expression of CCT6A mRNA in chicken granulosa cells is regulated by progesterone.

CCT6A, the zeta subunit of the chaperonin containing TCP1 complex, is the only cytosolic chaperonin in eukaryotes and is estimated to assist in the folding of multiple proteins including actin, tubulin, cyclin E, myosin, transducin and the Von Hippel Lindau tumor suppressor. In this study, we examined the expression of CCT6A and progesterone receptor (PGR) mRNA in various tissues of chickens and the regulation of CCT6A and PGR mRNA in ovarian granulosa cells. Northern blot analysis revealed that CCT6A had one transcript and was highly expressed in the ovary tissues from chickens at both the sexually immature and mature stages.

Detection of SNPs in the cathepsin D gene and their association with yolk traits in chickens.

CTSD (Cathepsin D) is a key enzyme in yolk formation, and it primarily affects egg yolk weight and egg weight. However, recent research has mostly focused on the genomic structure of the CTSD gene and the enzyme's role in pathology, and less is known about the enzyme's functions in chickens. In this paper, the correlations between CTSD polymorphisms and egg quality traits were analyzed in local Shandong chicken breeds.

[Construction and transduction of hNUDC shRNA interference lentiviral vector].

Aim: To construct a lentiviral vector carrying human nuclear distribution protein C (hNUDC)-specific shRNA (sh-NUDC-F) and knock down hNUDC expression in Dami cells by infection of the lentivirus.

Methods: After labeling of green fluorescent protein (GFP), sh-NUDC-F was cloned into lentiviral vector pRRL-cPPT-CMV-X-PRE-SIN, and the high-quality plasmid was transfected into 293T cells to produce lentiviral particles by the calcium phosphate method. After high-speed centrifugation, lentiviral particles were collected and determined for its titer.

[The construction of NUDC shRNA interference vector with red fluorescence protein].

Aim: Used RFP gene to construct a RNA interference vector for convenience to obtain the good effective hairpins sequence.

Methods: NUDC and RFP genes were cloned into pDs vector separately, resulting in pDs-NUDC- RFP. as above, human U6 promoter and 9 hairpins sequence of NUDC were cloned into the pDs- NUDC-RFP vector separately.