The objectives of this study were to determine if the addition of a cationic peptide to the feed formulation of weaned pigs decreases Salmonella and Campylobacter colonization of the pig’s gut and to investigate the effects of using cationic peptides as feed additives in weaned pig rations on the innate immune response of weaned pigs. Pigs were fed a feed ration containing 24 ppm of the BT TAMU cationic peptide for the duration of each part of the studies. In the Salmonella studies, pigs in both control and peptide groups were given Salmonella orally. Daily rectal swabs were taken and pigs were euthanized and cultured for the presence of Salmonella on day 7 after infection. Pigs fed the peptide had reduced fecal shedding of Salmonella and reduced Salmonella in the tissues compared to control pigs that did not receive the peptide. In addition, pigs fed the peptide had higher daily weight gains than did pigs that were not fed the peptide. No significant reductions of Campylobacter were found in pigs fed the peptide with preexisting Campylobacter infections. In innate immunity studies, one mechanism swine leukocytes use to kill microbes, called an oxidative burst, was found to be higher in pigs fed the peptide versus pigs that did not receive the peptide on all days it was measured. Leukocyte degranulation, another mechanism leukocytes use to kill microbes, was not found to be different between control and peptide-fed pigs. In summary, the addition of the BT TAMU peptide to weaned pig feed resulted in reduced Salmonella shedding in feces and reductions in tissue colonization. The peptide also stimulated the immune system of pigs fed the peptide, as indicated by an increased oxidative burst response in these pigs. Although no effects against Campylobacter were observed, this may have been due to the fact that all pigs used in the studies had preexisting Campylobacter infections. If Campylobacter-free pigs were available, the results may have differed. These studies indicate the BT TAMU peptide may be an effective alternative, immunologically-based strategy to the use of antibiotics to reduce Salmonella in swine.