Swine respiratory disease (SRD) is a persistent challenge in swine production, causing significant economic losses, particularly during colder months when barns are closed, and ventilation is limited. SRD, a complex of viral and bacterial infections, can lead to systemic inflammation, reduced growth performance, and poor feed conversion efficiency (FCE). However, recent research highlights soybean meal (SBM) as a tactical dietary adjustment to mitigate these effects and improve herd productivity.
The Hidden Costs of SRD
SRD, caused by pathogens such as PRRSV, Mycoplasma hyopneumoniae, and Streptococcus suis, not only suppresses growth rates but also increases costs through higher medication use and fewer thriving pigs. These costs are often hidden in barn closeout data, but estimates suggest SRD can add $3–$6 per pig in production expenses. The economic impact is even more pronounced during January through April, when cold weather exacerbates the prevalence of SRD pathogens.
The cumulative effects of SRD include:
- Reduced average daily gain (ADG).
- Poorer feed conversion efficiency (FCE).
- Lower carcass weights at market.
- Increased risk of cull pigs and compromised herd health.
Key Findings on Soybean Meal and SRD
Research on the use of SBM in pig diets during SRD outbreaks has shown significant benefits. These findings offer new hope for producers looking to mitigate the hidden costs of SRD through strategic dietary adjustments:
- Improved Growth Rates:
- Pigs fed high SBM diets (38–50% SBM) during SRD outbreaks experienced a 9.5% increase in ADG compared to those on low SBM diets.
- Carcass ADG saw an even greater improvement, with pigs on high SBM diets achieving a 12.8% increase.
- Enhanced Feed Efficiency:
- High SBM diets reduced whole-body FCE by 7.7% and carcass FCE by 9.7%, indicating significant feed savings per pig.
- On a 1,000-pig basis, feed savings from high SBM diets can translate into notable cost reductions.
- Increased Carcass Weight:
- High SBM diets resulted in an additional 3.8 pounds of carcass weight per pig, directly impacting profitability.
The Role of Functional Molecules in SBM
The benefits of high SBM diets are not solely attributable to their nutritional value as a source of protein and amino acids. Functional molecules (FM) found in SBM, such as isoflavones and bioactive peptides, play a critical role in mitigating the effects of SRD. These molecules contribute to:
- Reducing Oxidative Stress: Minimizes cellular damage caused by systemic inflammation during SRD outbreaks.
- Enhancing Immune Function: Improves the ability of pigs to fight off infections more effectively.
- Preserving Intestinal Integrity: Maintains a healthy gut barrier, reducing pathogen translocation and secondary infections.
- Lowering Pathogen Load: Functional molecules may exert antiviral and antibacterial effects, decreasing the overall pathogen burden.
By incorporating high SBM diets during periods of heightened SRD risk, producers can harness these functional benefits to improve herd health and productivity.
Practical Applications for Producers
Producers can apply the findings of this research by strategically increasing SBM levels in their diets during known high-risk periods for SRD, such as the winter-spring months. Tactical SBM use should be guided by:
- Dietary Adjustments:
- Increase SBM content by 30% or more compared to standard system diets during high-risk periods.
- Align SBM levels with amino acid requirements to optimize performance.
- Monitoring Key Metrics:
- Track carcass weight, feed costs, and medication expenses to assess the financial value of high SBM diets.
- Measure improvements in ADG, FCE, and overall herd health outcomes.
- Long-Term Planning:
- Implement prescriptive diets during early nursery and grow-out phases to mitigate the effects of SRD before they escalate.
- Use high SBM diets as a proactive strategy rather than a reactive measure.
Conclusion
The use of soybean meal as a dietary strategy to combat swine respiratory disease represents a significant advancement for the industry. By leveraging the functional benefits of SBM, producers can reduce the economic burden of SRD, enhance herd health, and improve profitability.
Incorporating SBM as a prescriptive solution during high-risk periods provides a practical, cost-effective approach to maintaining productivity in the face of disease challenges. With the right implementation, this strategy can transform how producers address SRD and other health-related growth impairments.
