Genomics and metabolomics of post-weaning return to estrus

Authors: Rempel, Lea; Rohrer, Gary; Nonneman, Danny - Dan

Submitted to: Journal of Molecular Reproduction and Development
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/28/2017
Publication Date: 9/1/2017
Publication URL: https://handle.nal.usda.gov/10113/5832865
Citation: Rempel, L.A., Rohrer, G.A., Nonneman, D.J. 2017. Genomics and metabolomics of post-weaning return to estrus. Molecular Reproduction and Development. 84(9):987-993. https://doi.org/10.1002/mrd.22820.

Interpretive Summary: The period of time between removal of suckling piglets and when the female sow is receptive for breeding, is known as the weaning-to-estrus interval. An extended weaning-to-estrus interval can be detrimental from both an economical and welfare perspective. A summation of existing and new results from genomic and metabolomic studies provided a better understanding of weaning-to-estrus interval. Genomic and genetic differences exist between females that have short and extended weaning-to-estrus intervals and indicated associations with reproductive pathways such as steroid hormone response and fertility, and metabolism pathways that influence protein synthesis and fat accretion for energy storage. Blood chemical profiles of female sows that did not return to estrus following weaning in comparison to those that had a normal weaning-to-estrus interval suggested chemical differences exist between these two populations. Further studies incorporating systems biology to derive a comprehensive understanding of post-weaning sows will assist with identifying; 1) possible candidate markers for identifying sows that will be most productive, and 2) nutritional and supplemental aids that will improve sow well-being while also improving economical efficiency.

Technical Abstract: The weaning-to-estrus interval is a multifaceted trait that has the potential to substantially improve production efficiency in today's global swine industry, if variation in this measure can be reduced. Systems-biology approaches should help close the knowledge gap and increase selection tools and management strategies—such as gilt development programs, farrowing, and lactation feeding programs—to decrease the weaning-to-estrus interval. Metabolomics, the study of small compounds within biofluids and tissues, provides links between genotype and phenotype. Given the complexity and influence of the environment on the weaning-to-estrus interval, incorporating metabolomics data will provide valuable insight and guidance for future physiological as well as genetic and genomic strategies to reduce this interval, thereby improving sow productivity.