According to Audrey McElroy, assistant professor of poultry science at Virginia Tech, adding capsaicin, the spicy component of peppers, to the diet of neonatal broiler chicks appears to increase their resistance to salmonella.
The research began with purchasing 1,530 commercial meat chicks, dividing them into three groups, and feeding each group a standard corn and soybean meal-based diet for 42 days.
McElroy fed the plain feed to the first group, but added five parts per million of pure capsaicin to the feed of the second group, and 20 parts per million to the third group's feed.
She then administered salmonella enteritidis to the chicks at 21, 28, and 42 days of age.
She found that both the low and the high level of capsaicin increased resistance to the Salmonella without adversely affecting feed consumption, weight gain, or the taste of the chicken when cooked.
"What we saw from our initial microscopic evaluation is that the capsaicin appears to cause a very mild inflammation in the intestines," McElroy says.
She is currently investigating the possibility that the presence of the capsaicin-induced inflammation might make it more difficult for the Salmonella to bind to the intestinal cells and, from there, to branch out to invade the blood, liver, and spleen.
"Or it may be that the capsaicin acts on the intestine to recruit immune cells, which then fight off the Salmonella," she said Her current research is designed to evaluate any observable effects of capsaicin directly on Salmonella in laboratory conditions, the effects of capsaicin on the intestinal environment, and the most economical scheme of feeding capsaicin to commercial poultry.
According to McElroy, salmonella typically results in little to no observable illness in chickens, but it is a disease of concern to the industry due to its ability to cause human illness.
"I think there's probably less Salmonella in our poultry today than there was in the past, because the industry has taken preventative measures," she says.
"But it would be a real breakthrough if we could find a way to reduce levels even further, without the use of antibiotics."
"If we can prove that feeding capsaicin to birds does reduce Salmonella in a commercial poultry-production situation, it would provide a non-antibiotic way of reducing food-borne pathogens," she says.
"Consumers want an antibiotic-free product, and this may provide the answer."