Probiotics help produce safer, healthier chickens, researchers discover

Guelph, ON – Giving chickens probiotics – dietary supplements that contain live beneficial bacteria – stimulates their immune system and reduces the Salmonella bacteria in their gut by more than 99%, a University of Guelph professor and an Agriculture and Agri-Food Canada food researcher have found.

We looked at the immune-enhancing ability of the probiotic and, lo and behold, the probiotic actually seems to be quite an immune stimulator, said Shayan Sharif, a pathobiology professor in the Ontario Veterinary College, who worked in collaboration with James Chambers of Agriculture and Agri-Food Canada. Their research was recently published in “Clinical and Vaccine Immunology”.

This means chickens treated with probiotics early in life are able to mount higher immune responses and, as a result, may be better protected against disease-causing microbes, said Dr Sharif. After looking at the antibodies in the intestine and blood of the chickens, we found that the antibodies were more than twice as high in chickens treated with probiotics.

The researchers also looked at two kinds of Salmonella that are most prevalent in Canada and found that some probiotics reduce, to less than one percent, the level of colonization of Salmonella in the chicken gut. The gut contents sometimes contaminate carcasses, depending on how the meat is processed, which puts consumers at risk of getting sick, said Dr Sharif. Reducing Salmonella in the chickens digestive tract could lead to more Salmonella-free chicken products on store shelves.

In the studies, one-day-old chicks were treated with probiotics and one day later were given Salmonella bacteria. The immune status and Salmonella bacterial load in the chicks was examined at various intervals and the positive results surfaced quickly, he said.

The study looked at a repertoire of probiotics alone and in combination with prebiotics (food substances that promote the growth of beneficial bacteria in the intestines). We also found that the combination of prebiotics and probiotics could reduce the existence of bad bacteria – those that are harmful for humans – in the chicken gut substantially, said Dr Sharif.