The first concern is inflammatory stress, due to high feed intake and/or coccidiosis. Broilers have high genetic potential with significant feed intake capacity. Even minor digestion and absorption violations increase the quantity of nutrients available to opportunistic bacteria in the gut. Any resulting chronic inflammation or coccidiosis lesions can cause villus atrophy.
Some nutritional factors can favour potential pathogens like Clostridium to the cost of other beneficial bacteria, such as Lactobacillus. This high stressor pressure can become a vicious circle.
A damaged gut displays villi fusion, excessive mucus production and an immune reaction. Further inflammation then appears, following these reactions.
Fusion of the villi leads to a reduced exchange surface, with lower water absorption (thus watery faeces) and less nutrient absorption. These nutrients will then be more available for opportunistic bacteria. Without appropriate action, this vicious circle will cause increased damage, and possibly even death for birds with necrotic enteritis.