Genetic variations for egg quality of chickens at late laying period revealed by genome-wide association study

Liu, Zhuang; Sun, Chang; Yan, Yong-Bin; Li, Guangqi; Shi, Fengying; Wu, Guiqin; Liu, Aiqiao; Yang, Ning

doi:10.1038/s41598-018-29162-7

Cited by 60 publications

(50 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…During the late laying period, egg quality is rapidly declined along with a higher cracked rate, increased egg size, thinner eggshell, lower albumen height, shortened storage time and poor flavor [5,23]. Eggshell thickness and strength were an essential attribute for egg production [24], and the improvement of eggshell quality was of great importance for late laying period hens.…”

Section: Discussionmentioning

confidence: 99%

“…Moreover, there is increase in feed conversion ratio, caused by poor egg production and feed utilization. In parallel, the egg weight and size are increased, eggshell thickness and breaking strength, and Haugh unit (HU) are reduced as the hens aged, resulting in higher cracked egg rate (% cracks), shortened egg storage time and poor flavor [4,5]. Therefore, continuously increasing concern is now focused on improving the reproductive performance, feed efficiency and egg quality of the late laying period hens.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Glycerol Monolaurate Enhances Reproductive Performance, Egg Quality and Albumen Amino Acids Composition in Aged Hens with Gut Microbiota Alternation

Liu

et al. 2020

Agriculture

View full text Add to dashboard Cite

As it is known to all that the laying rate of commercial laying hens is significantly decreased during the late laying period, paralleled with increased feed conversion rate (FCR) and declined egg quality. However, recent studies demonstrate that reproductive performance as well as egg quality in aged hens can be largely improved by feed supplements. Among them, glycerol monolaurate (GML), a monoglyceride of medium chain fatty acids, is regarded as a promising supplement in poultry production. The aim of this experiment was to evaluate the effect of dietary GML on laying performance, serum biochemical indices, egg quality and gut microbiota in hens during 40–64 weeks of age. A total of 378 (40-week-old) Hy-Line Brown laying hens were randomly assigned into three treatments (21 hens/replicate and 6 replicates/treatment). The control group received a basal diet, and the treated groups fed basal diets containing 150 and 300 mg/kg GML. The results revealed that laying rate (p < 0.05) was significantly increased and the FCR (p < 0.05) was reduced in GML-containing groups compared with the control group. The egg quality (including eggshell thickness and strength) was notably improved by GML supplementation at the later late laying period, and the content of total amino acids and flavor amino acids in the albumen were also increased. Inclusion of 300 mg/kg GML in diet increased the levels of laying-related sex hormones (serum follicle stimulating hormone, luteinizing hormone and estradiol, p < 0.05), serum calcium and lipid (total serum cholesterol, triglycerides and low-density lipoprotein cholesterol, p < 0.05). Moreover, the community and microbial function of gut microbiota were notably altered by GML supplementation. These findings revealed that dietary GML improved the reproductive performance and egg quality mainly by stimulating the sex hormones secretion, serum calcium metabolism and nutrients utilization, which provided us a new approach to simultaneously promote the egg production and improve the egg quality at aged hens.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Glycerol Monolaurate Enhances Reproductive Performance, Egg Quality and Albumen Amino Acids Composition in Aged Hens with Gut Microbiota Alternation

Liu

et al. 2020

Agriculture

View full text Add to dashboard Cite

show abstract

“…Currently, one of the trends in management practices of laying hybrids is that the laying cycle of hens is being extended despite the inferior egg quality. Thus, it is essential to work on the improvements of egg quality when considering prolonged laying cycle (Liu et al 2018).…”

Section: Introductionmentioning

confidence: 99%

How genotype influences the egg quality in the second half of laying cycle?

Kraus¹,

Zita²,

Krunt³

et al. 2020

JCEA

View full text Add to dashboard Cite

The objective of this study was to determine and compare egg quality from two genotypes of brown egg-laying hens in the second half of laying cycle (from 46 to 74 weeks of age). Commercial hybrids Hisex Brown and Lohmann Brown Classic were used in this study. Both genotypes were kept in enriched cages. 1920 eggs were evaluated. The significant effect of genotype was found in all evaluated traits except for the eggshell proportion and reflectivity. Results show that eggs from Lohmann Brown Classic hens had a superior quality in majority of the evaluated traits. Higher values were observed in main egg quality traits, such as egg weight (by 1.45 g, P≤0.0001), eggshell strength (by 2.48 N*cm-2 , P≤0.0005) and Haugh units (by 3.27, P≤0.0001). The significant effect of age was determined in all selected egg quality traits. The egg weight increased with the age, meanwhile other traits such as egg shape, albumen and yolk index, Haugh units and eggshell strength decreased. The trend of the rest of evaluated traits was ambiguous. Furthermore, the interactions between genotype and age were determined. Regarding the extension of laying cycle, further research is required, because the egg quality rapidly decreases with the age.

show abstract

“…Chicken eggs are rich in protein, fatty acids, vitamins, and minerals, and are measured as an excellent source of animal protein. With the enhancement of laying hens’ production performance, the laying age of commercial laying hens has been prolonged from the first 72–80 weeks, and some breeding companies have even-continued the laying cycle to 100 weeks, recommending the breeding program “breeding for 500 eggs in 100 weeks” [1,2,3]. However, the rapid drop in egg-laying rates at the end of the laying cycle has severely hindered the attainment of this goal.…”

Section: Introductionmentioning

confidence: 99%

Novel Polymorphisms in RAPGEF6 Gene Associated with Egg-Laying Rate in Chinese Jing Hong Chicken using Genome-Wide SNP Scan

Azmal

Bhuiyan

Omar

et al. 2019

Genes

View full text Add to dashboard Cite

The improvement of egg production is of vital importance in the chicken industry to maintain optimum output throughout the laying period. Because of the elongation of the egg-laying cycle, a drop in egg-laying rates in the late laying period has provoked great concern in the poultry industry. In this study, we calculated the egg-laying rate at weeks 61–69 (60 days) of Jing Hong chickens parent generation as the phenotype, and the genotype were detected by the chicken 600K Affymetrix Axiom High Density (HD) Single Nucleotide Polymorphisms (SNP)-array. The Genome-Wide Association Study (GWAS) result showed that the egg production trait is significantly associated with five SNPs (AX-75745366, AX-75745380, AX-75745340, AX-75745388, and AX-75745341), which are in the rap guanine nucleotide exchange factor 6 (RAPGEF6) gene on chicken chromosome 13. A total of 1676 Chinese commercial Jing Hong laying hens—including two populations, P1 population (858 hens) and P2 population (818 hens)—were genotyped using the Polymerase Chain Reaction-Restriction Fragments Length Polymorphisms (PCR-RFLP) method for the association analysis of egg-laying rates for the verification of the GWAS results. Genotypic and allelic frequencies of five SNPs were inconsistent with Hardy–Weinberg equilibrium, and the average population genetics parameters considering all the SNP values; i.e., gene homozygosity (Ho), gene heterozygosity (He), the effective number of alleles (Ne), and the polymorphism information content (PIC) were 0.75, 0.25, 1.40, and 0.20 in P1; 0.71, 0.29, 1.46, and 0.24 in P2; and 0.73, 0.27, 1.43, and 0.22 in P1 + P2 populations, respectively. The association analysis results revealed that out of the five polymorphisms, three of them (AX-75745366, AX-75745340, and AX-75745341; Patent applying No: 201810428916.5) had highly significant effects on egg-laying rates according to the GWAS results. Population-specific association analyses also showed similar significant association effects with this trait. Four haplotypes (AAGG, AAAG, AGGG, and AGAG) were inferred based on significant loci (AX-75745340 and AX-75745341) and also showed significant associations with the egg-laying rate, where haplotype AAGG had the highest egg-laying rate, with the exception of the egg-laying rate in P1 population, followed by other haplotypes. Furthermore, genotypes TT, AA, and GG showed the highest egg-laying rate compared to the corresponding genotypes at AX-75745366, AX-75745340, and AX-75745341 SNP loci in P1+P2, respectively. A similar result was found in the population-specific analysis except for the P1 population, in which TC genotype showed the highest egg-laying rate. No significant association was found in the egg-laying rate during the 60 days laying period for the SNPs (AX-75745380 and AX-75745388) in any group of population (p ≥ 0.05). Collectively, we report for the first time that 3 SNPs in the RAPGEF6 gene were significantly associated with the egg-laying rate during the later stage of egg production, which could be used as the potential candidate molecular genetic markers that would be able to facilitate in the selection and improvement of egg production traits through chicken breeding.

show abstract

Genetic variations for egg quality of chickens at late laying period revealed by genome-wide association study

Cited by 60 publications

References 48 publications

Glycerol Monolaurate Enhances Reproductive Performance, Egg Quality and Albumen Amino Acids Composition in Aged Hens with Gut Microbiota Alternation

Glycerol Monolaurate Enhances Reproductive Performance, Egg Quality and Albumen Amino Acids Composition in Aged Hens with Gut Microbiota Alternation

How genotype influences the egg quality in the second half of laying cycle?

Novel Polymorphisms in RAPGEF6 Gene Associated with Egg-Laying Rate in Chinese Jing Hong Chicken using Genome-Wide SNP Scan

Contact Info

Product

Resources

About