Probiotics to the rescue of pigs: A study against Salmonella in a bioreactor

Authors: Amély Grandmont, M. Sc., Université de Montréal and Alexandre Thibodeau, professor at the Chaire de recherche en salubrité des viandes at the Université de Montréal

Article published in Porc Québec, April 2024, Volume 35, Page 20

When we talk about salmonella in food, we immediately think of food infections and intestinal disorders. Foods, of plant and especially animal origin, can transmit this bacteria to humans. One of the foods that can be incriminated is pork meat. Indeed, pigs are carriers; the bacteria hides in their intestines. They can also develop a disease like in humans, but generally this is without symptoms. Reducing Salmonella in pigs will therefore bring benefits mainly for public health and also for animal health. This is why the Chaire de recherche en salubrité des viandes (CRSV) studied a new probiotic, in partnership with NUVAC Éco-Sciences (Québec, Valcourt), thanks to the financial support of the Ministère de l’Agriculture, des Pêcheries et de l’Alimentation du Québec (MAPAQ) and the Swine and Poultry Infectious Diseases Research Center (CRIPA), with the aim of reducing the presence of Salmonella in pigs.

Normally, many animals are needed for this type of project, especially if we want to test several doses and methods of administering the product. To maximize the use of animals, it is therefore important to be able to anticipate how the product will react in the animal in order to select the best application conditions. To do this, a bioreactor system was used. This device is designed to take pig fecal matter, filled with microorganisms, and inoculate it into a culture medium in the laboratory. In this way, the bacteria from the pig's intestine multiply there. It is therefore possible to introduce Salmonella and subsequently study it in a more representative environment than a simple lab bench. It is a system halfway between the animal and classic bacteriology. If a product has no effect in the bioreactor, the chances of it working in the animal are then almost zero.

This study is a new tool to improve sanitation.

The bioreactor made it possible to study two modes of administration of the probiotic, i.e. a dose administered continuously for 24 hours and a daily dose added every 24 hours for 3 days. This study shows not only an inhibition of Salmonella inside the reactors, 48 ​​hours after the continuous treatment and 24 hours after the second daily administration, but also a change in the microbiota (bacterial populations present in the bioreactor) after the treatments. Continuous administration showed the most change in the microbiota, including a decrease in several populations present within it. On the other hand, daily administration disrupted the microbiota less. Given that the daily dose also inhibited Salmonella, this dose should therefore be prescribed in animals. The study therefore made it possible to identify, with minimal use of animals, which mode or daily dose of probiotic is the most appropriate for use on farms. This study therefore provides a new tool for pork producers to improve the safety of their production. This probiotic could be used to prevent Salmonella contamination in pig farms, thereby reducing its incidence on farms and especially on our plates!