Novel approaches to identify optimal antiviral probiotics for swine industry in low-income countries
Effective control of major enteric viral pathogens (including rotaviruses) of livestock is critical for swine health and production. Unfortunately, poor biosecurity practices in many developing countries and the lack of efficacious vaccines and antivirals represent major challenges in controlling rotaviruses. Antibiotic-related practices, including preventative, indiscriminate, or improper antibiotic use, require urgent attention. Probiotics have historically been used to improve feed efficiency and the health of livestock animals. However, most findings on the health-promoting or antiviral effects of probiotics were inconclusive, inconsistent, or incomplete.
Rotaviruses recognize histo-blood group antigens on intestinal epithelial cells as attachment factors. This may affect their pathogenesis, and while certain lactobacilli bind different histo-blood group antigens that can block virus attachment to cells, some proteobacteria produce histo-blood group-like antigens that may directly bind different viruses.
The research team, a collaboration between Ohio State University and the University of Nairobi, seeks to understand if these underappreciated mechanisms of probiotic action can provide a stronger rationale for selection of optimal in-feed alternatives to compensate for the loss of antibiotic-related benefits and to combat enteric viruses and the associated secondary bacterial infections. These tripartite virus-bacterium-histo-blood group antigens interactions of selected immunomodulatory and antiviral probiotic/commensal bacteria in vitro and in vivo will be systematically evaluated. Porcine small intestinal enteroids will be used to identify histo-blood group antigens-expressing and antigens-binding bacteria, and to evaluate their ability to block rotavirus infection. Neonatal piglets will be used to evaluate the effects of probiotic-histo-blood group antigens interactions on protection against viral infections. It is expected that this will help to reduce the use of antibiotics and improve sustainability of the swine industry in developing countries.