Madri Brink – Global Technical Manager, Orffa Additives B.V.
Mycotoxins are the most prevalent natural contaminant in food and feed. These secondary metabolites are produced by different types of filamentous fungi, commonly found in agricultural products. The presence of mycotoxins in crops and feed poses a significant challenge for poultry producers globally, as they can impair animal performance, lead to feed waste, and ultimately reduce profitability. It is impossible to produce a mycotoxin-free feed as mycotoxins are invisible and are characterized by their thermal stability. Therefore, it is crucial to apply solutions that can counteract in-feed mycotoxins and mitigate risk to animals.
Aflatoxins – A Hidden Risk
In South Asia, aflatoxins in particular present an extreme risk. Aflatoxins are produced by different species of Aspergillus. These fungi are the most common contaminants of maize, a widely used ingredient in poultry feed. While the climatic conditions in the region promote the growth of aflatoxin-producing fungi during crop growth and post-harvest storage, Asia’s fragmented farming systems and informal feed supply chains further contribute to the contamination risk. In a recent survey, it was found that about 57% of animal feed samples in Asia were contaminated with aflatoxins. Among the different types of aflatoxins produced, the most important are B1, B2, G1, G2 and M1 due to their toxic and carcinogenic properties. Chronic exposure to even low levels of aflatoxins can have significant negative effects on animal health. In addition, aflatoxins in animal feed also pose health risks to humans through the consumption of contaminated animal products such as meat and eggs, further underlining the need for effective mitigation solutions.
The Impact of Aflatoxins on Poultry Health and Profitability
Aflatoxins exert both clinical and subclinical effects on poultry, including:
- Digestive tract damage: these toxins can cause mucosal lesions and disrupt gut health, impairing nutrient absorption.
- Liver damage: aflatoxins are hepatotoxic, leading to fatty liver, inflammation, and even fibrosis.
- Immunosuppression: birds exposed to aflatoxins exhibit reduced disease resistance and weaker vaccine responses.
- Economic losses: lower growth rates, egg production, processing yield, reduced feed efficiency, reduced fertility and hatchability, and increased mortality, which result in substantial financial losses for producers.
Exposure to a single mycotoxin such as aflatoxins can already negatively affect the health and productivity of poultry. However, the co-occurrence of mycotoxins in feed is the rule rather than the exception, which can lead to synergistic or additive toxic effects. A recent study by Kolawole et al. (2025) indicated that broilers fed a mycotoxin contaminated diet, even at levels below EU regulatory limits, had a decrease in feed efficiency of up to 10.8% and an increase in feed consumption of 10.9%. This translates into an additional feed cost of €214,600 per year or ₹2,20,09,591 per year.
Clinoptilolite: A Natural Solution for Aflatoxin Mitigation
To counter the threat of aflatoxins, producers are increasingly turning to clinoptilolite, a natural sedimentary clay mineral. Its honeycomb-like crystalline structure and high cation exchange capacity allow clinoptilolite to function as a molecular “trap,” selectively and specifically adsorbing mycotoxins like aflatoxin B1. The mineral’s natural negative charge attracts positively charged toxins, binding them within its pores and preventing their absorption in the gastrointestinal tract. This mechanism ensures toxins are safely excreted, reducing their harmful effects.
In an in vitro study by the CALF lab of the National Dairy Development Board (NDDB) in India, Excential Toxin A showed aflatoxin B1 binding of up to 97.62%. Another in vitro study was set up by the Centre of Excellence in Mycotoxicology and Public Health at Ghent University in Belgium. Within this study, Excential Toxin A was tested for its binding capacity (%) to the main types of aflatoxins (AFB1, AFB2) via LC-MS/MS. The binding capacity was analysed at pH 3 and 7, simulating the stomach and small intestine, respectively. The binding capacity to the respective mycotoxins is expressed as follows: complete binding (“+++”>90%), partial binding (“++”>50%; < 90%), limited binding (“+”>10%; <50%) and no significant binding (“0”<10%). Excential Toxin A was shown to completely bind AFB1 and AFB2 at both pH levels (Table 1). These results suggest that Excential Toxin A can offer a high degree of protection against the four most important aflatoxins.
Table 1 Binding capacity of Excential Toxin A to the most important aflatoxins
| Aflatoxin | Binding capacity of Excential Toxin A |
| AFB1 pH3 | +++ |
| AFB1 pH3-7 | +++ |
| AFB2 pH3 | +++ |
| AFB2 pH3-7 | +++ |
A 35-day broiler study carried out at Kasetsart University in Thailand has shown that Excential Toxin A, a natural source of clinoptilolite, supports immunity and liver health in broilers challenged with aflatoxin B1. A total of 1,200 day-old broilers (Ross 308) were divided into five treatments: negative control (NC), positive control (PC, with 50 ppb aflatoxin B1), and three groups receiving the PC diet diluted Excential Toxin A (TA) at 1.0, 2.5, and 5.0 kg per ton of feed. The birds were vaccinated against Newcastle Disease (at 7 and 21 days of age) and Infectious Bronchitis (at 7,14, and 21 days of age).
Key Findings (Table 2):
- Performance: Supplementing broilers with 5 kg/ton of Excential Toxin A did not negatively impact broiler performance as indicated by the final body weight, growth, feed intake, and FCR. This indicates that the product selectively binds aflatoxins and none of the essential nutrients.
- Mortality: Reduced mortality rate in groups receiving 2.5 and 5 kg of Excential Toxin A.
- Immunity: Significantly improved (P<0.001) the Newcastle Disease (ND) antibody titer when birds were fed Excential Toxin A.
- Liver Health: Liver histopathology scores tended to be improved in the treatments supplemented with Excential Toxin A (P = 0.07), indicating reduced aflatoxin damage.
Table 2 Performance, antibody titer and liver histopathology scores of broilers fed Excential Toxin A when challenged with aflatoxin B1
| Treatment | Final Weight (kg) | Weight Gain (kg) | Feed Intake (kg) | FCR | Mortality Rate (%) | ND Titer | Liver score |
| NC | 2.37 | 2.33 | 3.63 | 1.56 | 1.67 | 2.20a | 2.06y |
| PC | 2.38 | 2.34 | 3.66 | 1.57 | 2.50 | 2.24a | 2.19y |
| PC+1 kg TA | 2.37 | 2.33 | 3.68 | 1.58 | 2.50 | 2.42bc | 1.56x |
| PC+2.5 kg TA | 2.39 | 2.35 | 3.66 | 1.56 | 1.25 | 2.36c | 1.44x |
| PC+5 kg TA | 2.36 | 2.32 | 3.70 | 1.60 | 1.25 | 2.47c | 1.88xy |
| P-Value | 0.940 | 0.941 | 0.891 | 0.172 | 0.580 | 0.001 | 0.073 |
Means within the same column with different superscripts (a,b,c) differ significantly (P<0.05) or (x,y) tend to differ (P<0.1).
In summary, the supplementation of Excential Toxin A, a source of clinoptilolite, in aflatoxin-contaminated feed can support immunity and liver health in broilers without negatively affecting productivity.
Safeguarding Poultry Health with Excential Toxin A
Aflatoxins in poultry feed are a hidden yet significant threat to animal health and farm profitability. Successful mitigation requires regular monitoring, proper storage practices, and the use of effective mycotoxin binders such as clinoptilolite. Excential Toxin A is a natural source of clinoptilolite with proven aflatoxin binding properties. It is authorized for all animal species and allowed to be used in feed for organic production. By staying vigilant and proactive against aflatoxin contamination, producers can protect their flocks, businesses, and consumers from the risks posed by mycotoxins.