Once suited up, we entered the building where, fortunately for us, the temperature was much cooler. This poultry building belongs to the Poulina Group, the largest producer of chickens for human consumption in Tunisia. The company, which operates in a number of poultry sectors, including production, butchery and processing, sees commercial interests in this research project because an antibiotic-free chicken would be easier to certify for export.
In front of us, over a thousand 19-day-old chicks chirp and roam freely in one of the 32 pens. From their very first days of life, the chicks are raised in ideal conditions, where temperature, light and humidity are rigorously controlled. These variables are progressively changed as their little bodies become increasingly covered in feathers. The chicks, who are the guinea pigs for the first stage of the in vivo project, are given unlimited food and water.
“The chicks don’t all eat the same thing,” explained Karim Ben Slama. The trial compares the four following diets: standard; without additives (control group); with a low dose of bacteriocins; and with a high dose of bacteriocins. “We weighed them for the first time last week. We’re tracking their growth,” said the researcher, gesturing to the various chickens with blue markings on their feathers. They were selected to be weighed weekly by the research team, which hopes that the bacteriocins will not harm their intestinal flora and will effectively prevent infections.
The Tunisian team expects the chickens to reach a weight of between 1.6 and 2 kg, the standard weight for butchery in the industry. Their carcasses will be examined in detail by the scientists. “This in vivo test will enable us to compare the intestinal flora of chickens that were fed standard feed with those fed feed supplemented with bacteriocins. This will enable us to judge whether or not the flora is disrupted,” explained Karim Ben Slama.
The experiment was halfway through at the time of my visit, but engineer Nciri Achref had already observed that “chicks fed with feed containing bacteriocin seemed bigger yet ate less than the others.” He looked at Karim Ben Slama to find the researcher smiling contentedly to hear this update. If bacteriocins promote growth as well as fight infection, they could become an alternative to antibiotics.
However, the scientists are realistic. Pathogenic bacteria can pull a fast one — they could also develop resistance to bacteriocins, just as they do to antibiotics. But maybe they won’t if you use a cocktail of bacteriocins! “The strategy would be to combine several bacteriocins with different mechanisms and spectrums of activity,” stated Ismail Fliss from Université Laval. Bacteria would have more difficulty resisting such a cocktail as opposed to a single bacteriocin.
Within the next year, the scientists hope to publish their results, which are currently being analyzed. This could be the start of a new era in the poultry industry!