Transcriptome-Based Analysis Reveals Relationship between Duck Eggshell Color and Eggshell Strength

Abstract

Background The strength of duck eggshells is essential for their storage, transportation, and processing, with various studies indicating a correlation between eggshell color and strength. Results Our research has demonstrated that green-shelled duck eggs exhibit higher eggshell strength compared to white-shelled eggs in the M2 Line Pekin Duck population. To this end, we established mRNA transcriptome profiles of 10 eggshell gland tissues and 10 liver tissues and constructed gene expression networks in the two tissues. RNA-Seq analysis suggests that genes associated with ion transport, transmembrane transport, and liver cell proliferation and differentiation in the eggshell gland could play important roles in eggshell formation. The liver of green shell duck has stronger cell proliferation ability to maintain its homeostasis, and the eggshell gland has stronger ability to secrete eggshell matrix protein, which may be the reason why the eggshell is stronger than that of white shell duck. Through Weighted gene co-expression network analysis (WGCNA), three related modules were found in eggshell gland and liver, respectively, and three key genes were screened in each tissue (eggshell gland: FKBP10, PPARG, MAP3K5, liver: PHLDA1, FLT3, CACNB4). They have important regulatory effects on eggshell color and eggshell strength respectively. Conclusions Through transcriptome sequencing of liver and eggshell gland of Pekin duck, multiple key genes regulating eggshell color and strength were screened, and finally a related gene network was constructed. These genes may participate in the regulation of eggshell formation through ion transport, transmembrane transport, and cell proliferation, which helps to fully understand the differences in eggshell formation between green-shelled duck and white-shelled duck.