Probiotics and their associated derivatives (paraprobiotics) are frequently utilized to improve animal health and productivity. However, their mechanisms of action are not fully characterized, especially in regards to the interactions with pathogenic bacteria in the gastrointestinal tract. This study tested the hypothesis that yeast probiotics and paraprobiotics directly interact with pathogenic bacteria differently. To test this hypothesis, the binding capability of 5 different yeast probiotics or paraprobiotics to gram-negative bacteria (Salmonella sp. and Escherichia coli O157:H7) and gram-positive bacteria (Listeria monocytogenes and Clostridium sp.) were analyzed. Yeast and bacteria were co-incubated on coverslips, washed extensively, and examined by scanning electron microscope to determine the extent of binding between products and pathogens. Membrane filtration was also used to quantitate the amount of bacteria capable of binding to the yeast product; yeast products and bacteria were co-incubated, filtered using 3µM membrane filters, and the resulting filtrates were assessed for viable bacteria by plate counts. All bacteria tested bound with nearly equivalent efficiencies (P > 0.05) against the live yeast probiotics tested (~26%). However, much variation was observed in the binding efficiencies with the paraprobiotics. The gram-positive bacteria had, as a group, a preference for binding to one paraprobiotic in comparison to the other 2 products analyzed (25% adhered vs. 47% adhered; P < 0.05), whereas the gram-negative bacteria had greater efficiency to bind to 2 paraprobiotics (40% adhered; P < 0.001). These data suggest that the use of probiotics and paraprobiotics as therapies needs to be specific to the pathogen of interest; thus indicating a need for “designer” probiotic/paraprobiotic feeding strategies. Further research is needed to analyze specific binding efficiencies of probiotics and paraprobiotics against infectious agents in vivo.