All meat lovers and farmers want healthy and high quality poultry. However, a cunning bacterium, Campylobacter, lurks within the gut of chickens.
As is often the case, chickens are not bothered by the presence of these new bacterial inhabitants within their gut. However, the presence of Campylobacter can turn a tasty meal into a nightmare for those of us who are meat lovers.
After ingesting contaminated poultry, individuals may develop a foodborne infection. To limit the risk to consumers, the poultry industry and researchers are working hard to develop a new means to reduce or prevent this bacterial pathogen from colonizing chickens.
Microbes normally and happily live in the exterior environment as well as inside animals. Like us, microbes grow within environments that provide the necessities for life; these microbes co-exist within “neighbourhoods” made up of many different species. In this neighbourhood, some microbes are long-term residents (i.e. they are always found in chickens), whereas other microbes are more recent arrivals (i.e. only colonize the chicken if allowed to enter) and others are transiting tourists that may disrupt the natural balance. Collectively, these populations within the gut are referred to as the microbiota.
As we are not able to culture and directly count all the microbes that exist within the gut, researchers are using an indirect method to monitor the populations that make up the microbiota. To do this, researchers collect samples and then detect and analyse the DNA sequences of the populations. The end result is that the researchers can identify the species that live within the gut, thus the DNA sequences act as individual passports for each species. Therefore, we can use these microbial passports to monitor the populations that make up the gut neighbourhood (i.e. the microbiota). It should be noted that the composition of these microbial neighbourhoods are specific for a given site (e.g. oral, digestive tract, skin) and specific for a given animal (e.g. dog, chicken, pig, human). In addition, the microbial neighbourhood will change over time, as different populations increase or decrease, for better or worse, in response to illness, food or stress.
Understanding changes in the microbiota is becoming a new and potentially vital part of modern medicine as well as veterinary medicine. For example, it is believed that altering the human microbiota could lead to a cure for obesity, reduce food allergies or even reduce the development of autism spectrum disorder (ASD). In animals, the discussion is focused on maintaining a microbiota that will improve resistance to infectious diseases and stabilize and improve growth performance. Within the agri-food industry, these changes aim to increase meat safety and quality, while reducing the cost to consumers.
The optimism and promise associated with microbiota research has yet to translate into tangible results, mainly due to a lack of data and few applications that have been rigorously tested and proven. Therefore, time, patience and advanced studies are still needed. To this end, several research teams are currently participating in an advanced study where they have identified specific microbiota associated with animal welfare and have developed food additives that are thought to maintain a beneficial microbiota.
Given that the microbial neighbourhood influences our overall health, it’s important to understand how a new arrival will impact on the existing population. This brings us back to the recent arrival in the chicken gut neighbourhood, Campylobacter. A research group from the Research Chair in Meat Safety (RCMS) at the Université de Montréal, made up of Alexandre Thibodeau, Philippe Fravalo and Ann Letellier, is studying how the colonization of chickens by Campylobacter affects the existing intestinal microbiota. To achieve their goals, they have teamed up with Julie Arsenault, an epidemiologist at the Université de Montréal, and Étienne Yergeau, an expert on microbiota analysis at the National Research Council of Canada. This collaboration led to the discovery that the population diversity within the chicken caecum is not drastically affected by the arrival of Campylobacter. However, the relationship among specific neighbours is affected and may cause some members to move out. In summary, Campylobacter’s arrival to the chicken gut neighbourhood is not good news for some members of the chicken caecum community, whereas other members will help and facilitate Campylobacters move and integration within the community. This work provided insight into the population dynamics within the chicken gut in the presence of Campylobacter and should serve as a reference for researchers looking to develop methods that aim to reduce the presence of Campylobacter within chickens.
Source : PLOS one 2015; 10(7) e0131978. Chicken Caecal Microbiome Modifications Induced by Campylobacter jejuni Colonization and by a Non-Antibiotic Feed Additive. Alexandre Thibodeau, Philippe Fravalo, Étienne Yergeau, Julie Arsenault, Ludovic Lahaye, Ann Letellier.