By Sandrine Demers, Communications Strategist, Tricot Communication
Vahideh Vahdatmanesh has an endless curiosity that fuels her hard work. This thirst for knowledge and perseverance have been the driving forces behind her graduate studies and her significant role in dairy production research in Iran and Canada.
Nurturing her knowledge through animal nutrition
Originally from Iran, Vahideh began her academic journey in animal sciences in her home country. Her bachelor’s degree, primarily focused on animal nutrition and microbiology, sparked a particular curiosity in her that drove her to delve deeper into research in these fields.
Driven by a growing interest in animal and human nutrition, she decided to pursue her master’s degree in animal nutrition. In Iran, the research environment requires students to specialize, starting at the master’s level, in a specific production sector: dairy, poultry, aquaculture, or swine. Vahideh chose dairy production, motivated by a desire to learn. This choice proved particularly astute, as this specialization combines both animal and human nutrition, effectively killing two birds with one stone for her areas of interest.
Specifically, Vahideh’s master’s research focused on improving milk production and meat quality by targeting the animal’s rumen, one of the first compartments of the ruminant digestive system. More precisely, she had to balance the ruminal microbiota through diet to reduce associated diseases and thereby achieve better milk and meat production.
After her master’s degree, she worked for eight years in an animal feed plant, in the research and development department. One of her tasks: finding the ideal feed ration to maximize milk production in cows. When a cow reached 45 litres a day, it was a great success!
The student jokingly describes herself as a “research freak,” someone passionate about research, and that passion is evident as soon as she talks about her journey. When Vahideh started working on dairy cow nutrition, she told herself, “Okay, I don’t think I’m done yet. I want more!”
Her fascination with the dairy industry led her to cross the ocean to pursue her PhD in Quebec. The Iranian dairy sector is a major industry, but it remains less structured and productive than in Canada or Australia, according to Vahideh. She was also surprised to learn that some Canadian producers play music for their cows to reduce stress and boost milk production.
In Iran, producers place less importance on research in their sector. That is precisely what she loves about Canada, and Quebec in particular. She feels she is making a real difference. Here, producers stay informed and, above all, take an interest in research advances to improve their operations.
When Vahideh decided to move to Canada for her graduate studies, she was looking for a specialist in science, animal nutrition, and microbiology. That’s how she discovered the articles by Dr. Ismail Fliss, a full professor at Université Laval and a world-renowned expert in food science. He is also a specialist in natural antimicrobials and bacteriocins. During a meeting, Dr. Fliss presented his future research project to her and invited her to participate as part of her doctoral studies.
It was an offer Vahideh couldn’t refuse: “I wanted more. I really wanted that PhD. I thought about it all the time; it never left my mind.”
Countering losses in dairy production with bacteriocins
What excited Vahideh about this research project was that it offered a concrete solution to an increasingly pressing problem affecting everyone in the dairy industry.
Overall, the work involved controlling bacteria of the Clostridium genus—which cause fermentation defects in dairy products and are found in cow feed—using bacteriocins, natural molecules capable of replacing certain antibiotics. In other words, it’s a bit like using the “weapons” produced by good bacteria to curb the growth of harmful bacteria. Clostridium spp. are naturally present in the soil. When forage, particularly silage, becomes contaminated with soil during harvesting, these bacteria can proliferate if fermentation is poor. Cows may then refuse this forage or consume it; this can lead to quality issues, such as unpleasant odours or butyric fermentation, and indirectly contribute to metabolic disorders like ketosis.
In addition to affecting cows, Clostridium spp. are also found in milk, even after pasteurization. Pasteurization aims to reduce the overall microbial load in milk, but this can create an environment conducive to microorganisms resistant to pasteurization. Consequently, Clostridium spp. can end up in cheese and cause defects. These defects render the cheese unfit for consumption and result in significant financial losses for cheese producers. Vahideh mentions having visited several Quebec farms to collect silage samples, which allowed her to directly observe the effects of these bacteria in the field. On one of the farms, a cow was on the verge of dying from severe ketosis linked to forage contaminated with butyric acid—a phenomenon to which Clostridium can contribute. On another farm, a producer told her that his farm was heavily affected and that he was eagerly awaiting the results of her research. These experiences reminded Vahideh of the importance and urgency of her work for the agricultural community.
Fortunately, the results are promising. Bacteriocins can neutralize several strains of Clostridium. The best way to observe these results is by examining the cheese itself. During the research, the team conducted several tests by making cheese in the lab with and without the bacteria, in order to compare the bacteria’s impact on cheese quality and verify the effectiveness of the bacteriocins.
Cheese contaminated with Clostridium spp. is particularly full of holes and cracks, compared to cheese free of the bacteria, which has almost no cracks.
To combat this harmful bacterium, a substance containing bacteriocins is sprayed directly onto the forage, eliminating Clostridium spp. at the source before they can proliferate.
The study was conducted by a small team: Vahideh, Dr. Ismail Fliss, research director, and Dr. Fadi Hassanat, co-supervisor and researcher at Agriculture and Agri-Food Canada. The study also benefited from the support of interns who contributed, among other things, to the cheese-making process.
This research is innovative. Although the use of bacteriocins is not new in human food, their application in the dairy industry represents a highly anticipated first for the sector.
A long-awaited and celebrated research project!
After delivering more than sixteen presentations in Canada and France, Vahideh’s research has captured the attention of the dairy and agricultural sectors. She was even awarded a prize for her poster presentation at the Techno Novalait Forum in 2025.
Now that the project is complete, legal procedures are underway to make this solution available to Canadian producers.
“What I love is that you grow as a person at the same time that you advance science.”
Vahideh Vahdatmanesh
She notably learned about metabarcoding, a technique that identifies and compares microorganisms present in an environment based on their DNA, which was very useful during her research. Despite a non-linear journey, the effort was worth it: “I recommend it. You feel proud for the industry and for yourself.”
Looking ahead, Vahideh would like to continue in this field and work in the dairy industry in Quebec. We wish her continued success, as her professional growth will benefit the entire industry.
