Assuring optimal gut health across production phases is a cornerstone to safeguard poultry performance and wellbeing. Despite being a health and welfare problem, gut health issues also result in long-term consequences if birds struggle to recover and raise biosecurity concerns for other birds and staff.
The gastrointestinal tract is responsible for breaking down feed particles into digestible nutrients that are absorbed into the bloodstream to satisfy metabolic requirements and fuel production outcomes effectively. Certainly, the gastrointestinal tract succeeds at doing so by operating together with the microbiota within, which helps digest fibrous components, stimulates intestinal walls, enhances the immune response of the host, and produces beneficial by-products for the host. Birds with a healthy gut are active and have a strong appetite, digest and absorb nutrients efficiently, and have a competent immune response. All these traits favour production outcomes and reduce recovery time in case of digestive upsets. Producers should therefore not underestimate the benefits of maintaining a healthy, functional gut microbiota-host interaction. But what are the main factors to look at when it comes to concerns about poultry gut health?
Poor barn biosecurity
Sound biosecurity practices lower the risk of pathogen entry and its impact on flock performance in the case of outbreak. Meanwhile, pitfalls in biosecurity protocols are gateways for potential pathogens to colonize birds’ gastrointestinal tract and develop enteric disorders that take a toll on flock performance. Therefore, revising barn protocols to prevent pathogen entry and control their spread if they make it in is the best strategy to protect poultry gut health beforehand.
Potentially harmful microorganisms can be found in poultry houses mainly as the flock ages. This may not be a problem for the current flock because they are already habituated to this environment, but raises biosecurity concerns for the following flock. Implementing all-in/all-out practices between batches, followed by thorough cleaning and disinfection is paramount to avoid gut health issues in naïve chicks or pullets. Failure to do so can result in digestive upsets, pasty vents, and diarrhea during the first week after placement that can lead to growth check and threaten birds’ survivability. In production systems with bedding and feeding enrichments, every effort should be made to prevent cross-contamination between batches. Harmful microorganisms proliferate on humid patches of organic matter from leftover feed and manure, and any dirty surface becomes a source for infection. Temperatures over 50 ºC can destroy unhealthy bacteria such as Salmonella and Campylobacter, and heat treatment is sometimes recommended to reduce pathogen load in litter but cannot solve the problem even if done correctly. In between batches it’s also good timing to clean and disinfect in-depth water lines to remove biofilms built up during the last production phase since health problems can also arise from here.
Mycotoxin-producing fungi can also grow under warm, humid conditions in feed bins, becoming a source of health problems if feed is stored inadequately for a long time. Pelleting lowers the load of potentially harmful microorganisms in ingredients used for feed formulation. Nonetheless, feed quality declines over time after preparation, particularly when feed remains in storage for extended periods. From a biosecurity standpoint, bins should be emptied before adding the new batch of feed into them and producers should check regularly that feed bins are not a hotspot for pathogens.
Weak(ened) microbiota
Developing a flourishing ecosystem of diverse, beneficial bacteria in the intestinal tract acts as a powerful barrier against potential pathogens present in the feed, water, and litter. Any of them can disrupt the fine balance between the intestinal microbiota and the host, jeopardising the proper functioning of the gastrointestinal tract and putting at risk the recovery of both if gut microbiota is not resilient enough to halt the new intruders. Weak microbiota health is a gateway for pathogenic bacteria such as Salmonella serotypes that take advantage of stressful events to colonise intestinal walls.
Feeding poultry diets supplemented with probiotics that survive pelleting, resistant to stomach acids, and capable of growing quickly in the small intestine is key to support a healthy gut microbiota and achieve consistent performance outcomes across ages. This is particularly important for newly hatched chicks and after stressful events that alter the microbiota balance due to a decline in beneficial bacteria. Transportation, thermal stress, and other welfare problems can lead to microbiota imbalance, and reinforcement with probiotics can help restore a healthy balance. Lastly, supplementation is also recommended after treating the flock with antibiotics, which wipe out the intestinal microbiota, and before temporarily metabolically demanding phases, such as the onset of lay.
Implementing poultry diets rich in prebiotics can also prompt the development of already-present beneficial bacteria. They feed on these components that are non-digestible by the host, stimulating their growth and activity. These fibrous compounds also strengthen the gastrointestinal tract becoming more robust and less prone to lesions due to intestinal wall breakage which ultimately benefits the overall functioning of the gastrointestinal tract.
Optimal gut health is no longer a bonus producers should aspire to under the right conditions and should be seen instead as a key management strategy for broilers and layers to achieve performance objectives and good flock welfare. Strong, resilient gut health boosts performance efficiency from within and supports the economic sustainability of poultry barns. To attain this goal and achieve optimal performance records consistently: biosecurity protocols must be solid, staff should fully comply with them, and producers should implement feeding strategies that strengthen the gastrointestinal tract and support beneficial gut microbiota across production phases.
