Introduction
Fumonisins are toxic compounds primarily produced by several fungi, predominantly Fusarium spp, like *Fusarium verticillioides* and *Fusarium proliferatum*. These mycotoxins are frequently found in cereal grains, especially corn, which is a crucial part of poultry diets. Their presence poses significant risks to bird health and can lead to economic losses for farmers. Among the fumonisins, fumonisin B1 (FB1) is the most common and from a toxicological standpoint the most thoroughly studies., Fumonisin B2 (FB2) and B3 (FB3) are less prevalent but can also pose concerns to the animals.
How Fumonisins Work
Fumonisins have a chemical structure similar to sphingolipids, which are essential for cell function. They inhibit a critical enzyme called ceramide synthase, leading to an accumulation of harmful substances in cells. This process can destabilize cell membranes and interfere with normal signaling, resulting in liver and kidney damage in poultry (Wang et al., 2016; Gelderblom et al., 2001).
The Dynamic Duo of Danger: Fumonisins and DON
Fumonisins (notably fumonisin B1) and deoxynivalenol (DON) are critical mycotoxins associated with health risks in both humans and animals. Their synergistic effects have garnered significant attention in scientific research, particularly regarding food safety and animal health. Here’s a concise overview of their interactions:
1. Toxicological Interactions
Cellular Pathways: Fumonisin B1 messes with the way cells make certain fats, causing a buildup that can lead to cell death and disrupt how cells send signals. Meanwhile, DON stops cells from making proteins, which also results in cell death but through different methods.
– Increased Cytotoxicity: The presence of both toxins can disrupt multiple cellular pathways, resulting in greater cytotoxic effects than either toxin alone hence increasing the challenge.
2. Immunomodulation
– Both mycotoxins can suppress immune responses. Their combined effects may lead to heightened immunosuppression, increasing vulnerability to infections.
3. Gut Microbiota Alteration
– Co-exposure to the combination of fumonisins and DON can disrupt the balance of gut bacteria, leading which hinders nutrient absorption and weaken immune function, increasing the risk of health issues.
Research indicates that animals exposed to both fumonisins and DON experience more significant decreases in growth and feed efficiency compared to those exposed to each toxin individually. Hence multiplying each others effect
Key Effects of Fumonisins on Poultry
1. Weakening the Immune System
Even low levels of fumonisins can suppress the immune response in birds. They affect the production of antibodies and important signaling molecules, making poultry more susceptible to infections and diseases (Tóth et al., 2012). This immune suppression is a significant concern for poultry farmers, as it can lead to increased morbidity in flocks.
2. Liver and Kidney Damage
The liver and kidneys are particularly vulnerable to the toxic effects of fumonisins. In affected birds, signs of liver damage may include enlargement and elevated enzyme levels, which indicate impaired detoxification (Voss et al., 2007). While kidney damage is less commonly studied, it can result in serious complications such as kidney failure (Gelderblom et al., 2001). Research has shown that broilers fed diets contaminated with fumonisins exhibit significant changes in their liver and kidney tissues (Li et al., 2016).
3. Poor Growth and Nutrient Absorption
One of the most visible impacts of fumonisin exposure is stunted growth in poultry. Studies consistently show that these toxins negatively affect weight gain and feed conversion ratios (FCR), primarily by impairing the gut’s ability to absorb nutrients effectively (Grenier et al., 2017). Damage to the intestinal lining compromises nutrient absorption, leading to slower growth and inconsistent body weights among birds. For example, broilers exposed to certain levels of FB1 showed reduced body weights compared to control groups (Marcela et al., 2020).
4. Gastrointestinal Health Issues
Fumonisins can cause damage to the gastrointestinal (GI) tract, resulting in problems like villus atrophy and increased intestinal motility. This damage weakens the gut barrier, allowing harmful bacteria to enter the bloodstream and increasing the risk of infections such as necrotic enteritis (Antonissen et al., 2015). Additionally, fumonisins can disrupt the balance of gut microbiota, promoting harmful bacteria while reducing beneficial ones, further compromising gut health (Grenier et al., 2017).
Strategies for Managing Fumonisin Risks
1. Routine Feed Testing and Quality Control
Regular testing of feed and feed ingredients for fumonisin contamination is essential to keep levels within safe limits . Quick testing methods, such as enzyme-linked immunosorbent assay (ELISA), can help ensure feed safety. Additionally, sourcing grains from trusted suppliers and maintaining proper storage conditions can significantly reduce the risk of contamination.
2. Using Mycotoxin Detoxifiers
Incorporating specific products like FUMzyme into poultry diets can help break down fumonisins into less toxic forms. These enzyme-based additives are designed to irreversibly convert fumonisins into safer compounds, making them less harmful to birds.
Fumonisins possess a complex molecular structure that significantly differs from that of other mycotoxins. This complexity makes it challenging for many binding agents, which are usually designed for more common mycotoxins, to effectively interact with and bind fumonisins. As a result, while high-quality bentonite mycotoxin adsorption technology is effective against aflatoxins, its efficacy is limited when it comes to fumonisins.
3. Improving Feed Storage Conditions
Moisture control is critical since fungi thrive in damp environments. Ensuring that feed is stored in dry conditions and properly ventilated can help prevent mold growth. Using antifungal additives can also be effective in inhibiting the production of fumonisins.
Fusarium species, while being field “field fungi” might continue to produce mycotoxins during storage specially in improper conditions.
Conclusion
Fumonisins pose a significant threat to poultry health, leading to immune suppression, organ damage, and poor growth performance. To effectively manage these risks, a comprehensive approach involving routine monitoring, proper feed management, and the use of detoxifying agents is essential for poultry producers.