In one respect, immunity is akin to the elevator at your office: only appreciated when it’s out of order. Given the impact of sick animals on their owner’s business, pig health is a top research priority. As scientists seek to enhance disease resilience in pigs for a Genome Alberta-led project, they may draw on the findings of another study on early life antibiotics. The lead on that study is Dr. Janelle Fouhse, Postdoctoral fellow in the Department of Agricultural Food and Nutritional Science in the Faculty of Agricultural Life and Environmental Sciences, University of Alberta.
“A prime aspect of resilience is the immune system,” said Dr. Ben Willing, Associate Professor, Department of Agricultural Food and Nutritional Science in the Faculty of Agricultural Life and Environmental Sciences at the University of Alberta.
“As well, a key driver of immune development is the microbiome, especially early in life when a lot of that development takes place.”
Microbes in the gut are stimuli that send signals to the immune system and shape its development. Of importance to scientists is that different microbes cause that system to develop in different ways.
“With this project on early life antibiotics, we are trying to use antibiotics to shift the microbial population in pigs one way or the other,” said Dr. Willing. “In doing so, we seek to understand how microbes shape the immune system and which microbes are associated with good or bad immune function.”
Researchers used an antibiotic treatment in the first weeks of life and then stopped. The result was that the microbial population was disrupted early on, but at seven weeks of age when the antibiotics were long gone from their system, those animals had the same microbiomes as other pigs.
“When we took live animals and injected salmonella in the abdominal cavity, however, the immune systems in pigs treated with antibiotics activated faster. It was interesting to see that while the microbiomes looked the same at seven weeks, the fact they were different in the first weeks of life caused immune systems to function differently.”
Based on those results, the research team thinks that the immune system of pigs treated with antibiotics may be more effective at clearing salmonella. Since the industry focus today is on lowering antibiotic use, the hope is that by understanding what the microbes are doing early on, science can try to mimic that without employing antibiotics.
A head start on health
“There are certain microbes that we view as candidates to employ in that mimicking process. If we can introduce them to pigs early in life, it could help promote immune system development. Also, as part of the larger project on disease resilience, we’re trying to identify microbes that support resilient animals. Ideally, the work on early life antibiotics will reveal microbial components that we can use to stimulate a more robust immune response.”
Ultimately, researchers envision their findings as informing industry practices on how to manage early life microbial exposure. If all goes as planned, producers could one day have a drug-free tool to arm their pigs against disease.
As with any breakthrough in science, this one requires a shift in perspective, something that is well underway.
“Where they used to view microbes as harmful, producers are now recognizing the potential benefits. Until now, this area has been really neglected, so there is much to learn. We’re happy with how things are progressing to date and excited to continue exploring this frontier.”