Feeding Level Is Associated With Altered Liver Transcriptome and Follicle Selection in the Hen

Broiler breeder hens given ad libitum access to feed have excessive ovarian follicle development with poor reproductive outcome. One strategy to improve their reproductive capacity is by restricting their feed intake. In this study, we sequenced the liver transcriptomes of hens fed ad libitum (FF, n=3) and hens given a restricted fed diet (RF, n=3) to get insight into possible signaling pathways affected by dietary treatment. Hens were reared according to commercial guidelines until 38 weeks of age, when they were assigned to either FF or continued on RF for 6 weeks. Liver mRNA samples from three hens in each group were sequenced using the Illumina HiSeq 2000/2500 technology at a depth of 100 bp. The sequencing quality of the data was determined using FastQC. Reads were aligned to UCSC Galgal4 using Tophat (v2.0.13) and transcripts were counted using cuffdiff (v.2.2.1). A multidimensional scaling plot (MDS plot) was generated to evaluate the variance among biological replicates and identified one FF hen as a sample outlier and this animal was removed from the analysis. Differential gene expression analysis was conducted using edgeR and yielded 120 differentially expressed genes. This study identified transcriptional differences in the livers of FF and RF hens which may signal metabolic status to the ovary. Liver mRNA profiles of 2 FF and 3 RF hens.