1a.Objectives (from AD-416):
1. Dissect the relationship between genetic markers and age at puberty and reproductive longevity.
2. Assess the effect of the interaction between energy input and SNP variation on age at puberty and sow reproductive longevity.
3. Identify procedures to apply and transfer marker-association results in selection programs to improve sow reproductive longevity.
1b.Approach (from AD-416):
The approach will be to use high-density genotyping and deep sequencing of expressed genes in gilts with novel phenotypes and differences in estimated breeding values for age at puberty to develop genomic markers that will aide in identification of sows with improved fertility. Markers identified in the resource population will be validated in at least three industry populations and a panel of validated genomic markers will provided to the industry through extension activity so that they may be adopted and used in selection programs to improve lifetime productivity of sows and increase efficiency of pork production.
The agreement between the University of Nebraska, Lincoln, Nebraska (UNL) and ARS scientists in Clay Center, Nebraska has been approved and established. Blood samples from gilts in replicates 10 and 11 have been collected. Laboratory analysis for serum concentrations of plasma urea nitrogen and insulin-like growth factor-I will commence this year. Gilts in replicate 12 have been genotyped and tissue collection from these gilts will begin this fall. Tissue samples will be processed to isolate RNA for deep sequencing using Illumina HiSeq technology to determine transcriptome profile between genotypes. Progress has been facilitated by phone calls and email correspondence between ARS PI and scientists at UNL. When necessary, meetings with scientists from ARS, UNL, and the University of Missouri occur in person at UNL.