2024
Pushing soybean meal and soyhull inclusion rates in grow-finisher pigs
Contributor/Checkoff:
Category:
Feed
Keywords:
Intact proteinMacronutritional bundleSwine
Parent Project:
This is the first year of this project.
Lead Principal Investigator:
Nicholas Gabler, Iowa State University
Co-Principal Investigators:
Project Code:
24-107-D-A-2-C
Contributing Organization (Checkoff):
Institution Funded:
Brief Project Summary:
Our overarching goal is to increase the usage of soybean meal and soyhulls in pig nutrition. Two objectives are proposed: Determine the maximum soybean meal inclusion rates (beyond requirements) in grow-finish pigs. Improving nutrient and energy release, growth and carcass performance of grow-finish pigs fed high soyhull formulated diets.
Information And Results
Project Summary

Project Objectives

Project Deliverables

Progress Of Work

Final Project Results

The overarching goal of this proposal was to increase the usage of soybean meal and soyhulls in pig nutrition. The first part of this study explored the effects of including high levels of soybean meal (SBM) in grow-finish pig diets. Soybean meal is a common protein and energy source in swine nutrition, with its inclusion often dictated by the cost relationship between SBM and synthetic amino acids such as lysine and methionine. Anticipated increases in domestic SBM production could lower its price, potentially encouraging higher-than-usual SBM levels in pig diets. However, the impact of over-formulating SBM on pig health and performance is not well understood. The research tested increasing SBM levels across four diet phases in grow-finisher pigs, with inclusion rates ranging from 15% to 75%, depending on the phase. All diets were corn-SBM based, iso-caloric, and met or exceeded amino acid requirements. Results showed that feeding SBM beyond amino acid requirements improved energy efficiency and reduced carcass backfat, without compromising growth performance or health after pigs adapted to high SBM diets in Phase 1. However, overfeeding SBM led to increased nitrogen excretion, which may require closer attention to barn ventilation and manure application management. Overall, the findings from this deliverable suggest high SBM inclusion rates above amino acid requirements can be used without adverse effects on grow-finisher pig performance or health. In the second part of the study, soybean hulls were evaluated in pig diets. Soybean hulls, a source of dietary fiber, can be included in grow-finish pig diets to reduce overall feed costs. However, dietary fiber is known to reduce nutrient digestibility, feed efficiency, and carcass yield. These negative effects may be mitigated by removing high-fiber diets before marketing. In this study, two experiments were conducted: experiment 1 involved four diets containing 0%, 7.5%, 15%, or 22.5% soybean hulls, while experiment 2 tested the effects of feeding pigs either a 0% or 22.5% soybean hull diet continuously or switching from 22.5% to a 0% fiber diet 13 or 27 days before marketing. These experiments aimed to assess the impact of soybean hulls on growth performance, nutrient digestibility, and carcass composition. Results indicate that while dietary fiber negatively impacts feed efficiency and carcass composition up to 22.5% inclusion, the performance of a carcass yield can moderately recover if high-fiber diets are withdrawn at least 13 days before marketing. In addition, compared to the NRC (2012), we estimated the digestible energy and metabolizable energy value of the soybean hull ingredient to be higher

Benefit To Soybean Farmers

The work highlighted that soybean meal can be formulated into swine diets and fed above requirement without any major negative impacts on pig health, growth and carcass performance. The benefit to U.S. soybean farmers in increase usage of this commodity as pig feed. Further, soybean hull fiber can be used at high inclusion rates (~22%) with the adoption on a withdrawal period without hurting carcass yields in pigs.

The United Soybean Research Retention policy will display final reports with the project once completed but working files will be purged after three years. And financial information after seven years. All pertinent information is in the final report or if you want more information, please contact the project lead at your state soybean organization or principal investigator listed on the project.