Location: Livestock Bio-Systems
Project Number: 3040-31320-001-000-D
Project Type: In-House Appropriated
Start Date: Jul 31, 2022
End Date: Jul 30, 2027
Objective:
Objective 1. Improve postnatal survival of preweaning piglets by identifying factors that contribute to within-litter variations on piglet growth and development.
Sub-objective 1.A: Determine the influence of ovarian responses (OR and serum P4 levels) during early gestation on within-litter variation in embryo elongation and uterine environmental responses in young females (Exp. 1) and multi-parous sows (Exp. 2).
Sub-objective 1.B: Evaluate the influence of regulatory factors (i.e., miRNAs) and nutrient transfer (i.e., metabolites) from maternal to fetal plasma across the placenta on divergent-sized fetal growth and within-litter variation during late gestation using a global approach (i.e., RNA-seq and non-targeted metabolomics, respectively).
Objective 2. Discover nutritional and environmental influences on gilt development and productivity to minimize reproductive failure of replacement gilts.
Sub-objective 2.A: Improve gilt development by understanding how growth relates to prebreeding anestrus.
Sub-objective 2.B: Minimize pubertal failure in gilts by identifying mechanisms in the anterior pituitary gland that are mediating the effects of nutrient balance on secretion of gonadotropin hormones necessary for initiation and maintenance of reproductive cycles.
Sub-objective 2.C: Improve neonatal management of replacement gilts by identifying how colostrum intake impacts early ovarian development.
Objective 3. Identify and evaluate biological predictors of sow performance and longevity within the breeding herd.
Sub-objective 3.A: Identify plasma biomarkers and blood transcript profiles from young pre-breeding females and associate those profiles with their subsequent breeding herd longevity.
Sub-objective 3.B: Evaluate USMARC swine population for effects of seasonal climate upon production parameters over the past decade.
Sub-objective 3.C: Generate hypomethylated, hypermethylated, or control pregnancies during summer or winter months to determine epigenetic impact upon placental, fetal, and piglet production.
Objective 4. Utilize and develop precision management technologies to improve preweaning piglet survival, gilt development, and sow longevity and increase efficiency of pork production.
Sub-objective 4.A.: Utilize ESF data to develop prediction models for gilt fertility (e.g., behavioral estrus) and sow welfare during gestation (e.g., abortion/miscarriage, lameness, appropriate body weight).
Approach:
Pork is the most consumed meat animal product globally. Improving lifetime efficiency of swine is critical to support an increasing global population. Improved lifetime efficiency will provide a high-quality source of protein while reducing the impact of swine production on the environment and ensuring the social welfare of animals. Lifetime efficiency is a complex trait that is influenced by genetic, environment, and management components. The comprehensive goal for this project is to further our understanding of these traits using physiology-, biology-, and technology-based approaches to provide improvements for fetal and neonatal health, gilt development, and sow longevity. We will accomplish this goal utilizing independently, and in combination, transcriptomics, metabolomics, proteomics, environmental data, and automated precision measurements (Figure 1). Within objective 1, we will investigate molecular pathways and signals that improve production of consistently sized piglets initiated shortly after conception. Objective 2 will delve into the influence nutrition has on the young female and the impact upon neuroendocrine gene expression as the gilt transitions into the active state of reproduction. Identifying biological markers that can assist in selecting females with longevity in the breeding system and investigating climate and therapeutics to assist with stayability are the central themes of Objective 3. In the fourth objective, feeding behavior and activity measurements of young gilts and gestating females will be collated and activity patterns will be generated to predict reproductive success or failure. The projects designed herein will clarify and contribute to the existing complex knowledge gap of swine productive life. Application of these studies will result in breeding females that are consistently well adapted, produce large litters of uniform piglets and remain fertile and healthy in the swine herd increasing production efficiency, improve economic competitiveness of U.S. pork producers, and contribute to basic understanding of biological and environmental influences upon swine production.