None of the candidates touted as suitable non-antibiotic alternatives have clearly been shown to match the cost-effectiveness, convenience and improved performance offered by current antimicrobials, says University of Tennessee-Knoxville animal scientist Alan Mathew.

Subtherapeutic or growth-promoting levels of antibiotics provide health-enhancing and production performance benefits which appear to be unmatched by most alternative compounds, he adds.

The first step to reduced reliance on antibiotics must be to optimize management and nutrition and reduce times of stress. Some alternatives include:

  • Acidifiers and pH optimizers: Dietary additives that can stabilize gut pH appear to be useful in maintaining pig health. Diet acidifiers may alter microbial populations in the gut as commonly fed at less than 2% of the diet for newly weaned pigs.
  • Optimizing the gut microflora and fermentation byproducts: Research has shown promise in this area in slowing the development of bacterial colonization of the gut. But large-scale changes in diet to affect health while maintaining energy content to support rapid growth of pigs will be especially challenging, says Mathew.
  • Development of intestinal mucins (proteins that occur in mucous membranes): These are produced by specialized cells in the gut that which help resist pathogens and may be promoted by inclusion of galactose in the diet. Galactose is a form of sugar less sweet and soluble than glucose.
  • Genetic resistance: It is suggested that genetic lines may be developed that will be more efficient in nutrient uptake and resistant to swine pathogens.
  • More strategic use of vaccinations: This may require a farm-specific approach to optimize timing and booster inoculations against specific disease organisms.
  • Mathew’s talk was presented in October at the Carolina Swine Conference in Raleigh.