Project Number: 8042-31630-001-00-D
Project Type: In-House Appropriated
Start Date: Jul 26, 2012
End Date: Jul 25, 2017
Objective 1. Identify proteins and their mechanism of action critical to the growth of the newborn pig by comparison of littermates with similar birth weights but with divergent growth rates. 1.A. Develop immunochemical methods and utilize an integrated proteomic and molecular approach to investigate the functional role of alpha-1 acid glycoprotein which is elevated in slow growing (SG) newborn piglets. 1.B. Identify additional plasma biomarkers for the early identification of SG piglets. Objective 2. Develop model(s) utilizing functional genomics to identify critical control points for economically important tissues of piglets impacted by growth rate. 2.A. Identify physiological differences between metabolically important tissues of SG and fast growing piglets at weaning by transcriptomic technology. 2.B. Perform a comparative analysis of runt (induced intrauterine growth retardation) and SG pigs to identify physiological similarities and differences between economically important tissues by transcriptomic technology. Objective 3. Develop industry applicable markers or screens to identify the slow growing piglet and develop strategies (nutritional/immunological) to promote more consistent and rapid growth. 3.A. Develop a strategy that can be readily adapted to large scale commercial environment to reduce growth variability in the pre- and post weaned piglet. 3.B. Identify and implement a treatment to bolster the growth performance of those pigs identified at postnatal day 1 as potential SG piglets.
Variability in growth rate between littermates within a production group leads to inherent inefficiencies in production of lean quality pork. This research will identify physiological mechanisms that contribute to piglet growth rate with the overarching goal of identifying markers predictive of growth rate to treat piglets of normal birth weight that, when left untreated, will exhibit slow growth. The research addresses four issues: 1) identification of plasma markers predictive for growth performance; 2) mechanisms of action for these markers and their relationship to growth rate; 3) identification of key physiological mechanisms modulating preweaning growth in critical metabolic organs; and 4) application of these markers as screens for use by industry and for use in an intervention strategy to improve performance of underachieving piglets. Plasma proteins will be identified that differ in concentration between slow and fast growing littermates and enzyme-linked immunosorbant assays (ELISA) for these proteins will be developed to identify the best predictors of growth rate. Functional analyses utilizing in vitro models will evaluate the mechanisms of action for these growth-related marker proteins in metabolically important tissues. Comparative genomic/proteomic analysis will be performed to elucidate mechanisms modulating preweaning growth in skeletal muscle, small intestine, and liver. Pathway analysis will examine relationships between the growth-related marker proteins and these physiological mechanisms. Lastly, additional swine populations will be surveyed with the ELISAs to complete development of the growth-related marker screen. Intervention strategies will then be developed to improve the growth rate of piglets predicted to underachieve.