Mycotoxin in Livestock: Effects and Management

Tony Mcdougal, a freelance journalist, once wrote in Poultry World, "The rising demand for eggs, meat, and milk in recent decades has driven higher EU imports of grains and cereals from developing countries with more tropical climates, where the occurrence of mycotoxins is higher—thus raising the prevalence of mycotoxins in EU data."

In the realm of livestock farming, mycotoxins are looming as silent threats, often hidden in animal feed. These toxic substances, produced by fungi, can contaminate various crops, including grains such as corn and wheat. Their presence is particularly rampant in warm and humid climates, where conditions foster fungal growth. Consequently, livestock farms in such regions face heightened risks of mycotoxin contamination, which can compromise animal health and productivity.
〈Related Article: Mycotoxin and Gut Microbiota Interactions〉
 

What is Mycotoxin?

Mycotoxins, which are toxic secondary metabolites produced by various fungal species, are commonly found in contaminating essential food staples and animal feeds. Often, a single fungal species may concurrently produce multiple mycotoxins, while different fungi can proliferate within the same plant, resulting in the co-occurrence of multiple mycotoxins. These fungi invade and generate mycotoxins during crop growth, as well as throughout storage and transportation processes.
 

Types and Sources of Mycotoxins

Among the most significant mycotoxins detected in animal feed are aflatoxin B1 (AFB1), ochratoxin A (OTA), fumonisin B1 (FB1), deoxynivalenol (DON), T-2 and HT-2 toxins, and zearalenone (ZEN). Additionally, emerging mycotoxins such as beauvericin (BEA) and enniatins (ENNs) have been identified in feed commodities. However, the discussion regarding these toxins remains limited due to the lack of regulatory measures.

The presence of mycotoxins in the feed chain primarily stems from fungal infections in crops and the utilization of mold-contaminated grains and forage in animal feed formulations. This contamination poses significant risks to animal health and well-being, highlighting the critical need for effective management strategies to mitigate mycotoxin exposure in livestock diets.

〈Related Article: Effects of DON and antidote on pro-inflammatory mRNA expression of broilers〉

Aflatoxins

Aflatoxins (AFs) originate from fungi within the Aspergillus genus, predominantly Aspergillus flavus and A. parasiticus, producing four main types: AFB1, AFB2, AFG1, and AFG2. Recognized as highly toxic mycotoxins, AFB1 is notably identified as a potent hepatocarcinogenic agent. AFs are classified by the International Agency for Research on Cancer (IARC) as carcinogenic to humans (group 1). Their entry into the human food chain occurs through direct consumption of contaminated crops or processed foods and indirectly via animal products derived from animals fed with AF-contaminated feeds. This contamination, particularly when AFB1 is present in feed consumed by dairy cattle, can lead to various symptoms and pose health risks through the metabolization of AFB1 into AFM1, excreted into milk.
 

Deoxynivalenol (DON)

Deoxynivalenol (DON), also known as vomitoxin, is a trichothecene mycotoxin primarily produced by Fusarium graminearum and commonly found in grains like wheat, corn, barley, and their by-products. It significantly impacts monogastric animals, notably pigs and poultry, through contaminated feed. Pigs, particularly sensitive due to their high wheat-based diets, exhibit reduced feed consumption and weight gain upon exposure to DON. This toxin also disrupts growth, immune response, and reproductive performance in pigs. Although poultry are affected by DON, their susceptibility varies due to differences in metabolism. The adverse effects on poultry growth are inconsistent, with low concentrations reducing feed consumption and higher doses causing gastrointestinal lesions, especially in the duodenum and jejunum.
 

Zearalenone (ZEA)

Zearalenone (ZEA) is a mycotoxin produced by various species of Fusarium fungi, commonly found in grains such as maize, wheat, barley, and oats. It is structurally similar to estrogen and is classified as an estrogenic mycotoxin. ZEA can contaminate animal feed and, through it, human food, posing health risks to livestock and humans alike. In animals, ZEA consumption can lead to reproductive issues, including hyperestrogenism and infertility, particularly in swine. Due to its estrogenic properties, ZEA exposure in humans has been associated with hormonal disruptions and adverse reproductive effects. Effective management strategies are crucial to mitigate ZEA contamination to ensure food and feed safety.
 

Fumonisins

Fumonisins (FBs), typically classified as Fusarium toxins, are produced by various species within the Fusarium genus, notably F. verticillioides and F. proliferatum. The primary toxins include FB1, FB2, FB3, and FB4, with FB1 recognized as the most prevalent and toxic. Classified as a possible human carcinogen (group 2B) by the International Agency for Research on Cancer (IARC), FBs disrupt sphingolipid biosynthesis, due to their structural similarities with sphingolipid precursors, rather than inducing direct DNA damage. EU guidance levels set the total for FB1 and FB2 at up to 60,000 μg/kg in maize and maize products for feed materials, and range from 5,000 μg/kg to 50,000 μg/kg for complete and complementary feedingstuffs, depending on the animal species and age.
 

Ochratoxin A  (OTA)

Ochratoxins are primarily produced by Aspergillus ochraceus (A. ochraceus), but other Aspergillus species such as A. carbonarius, and Penicillium strains like P. verrucosum and P. nordicum, can also produce them. Meanwhile, ochratoxin A (OTA), a potent nephrotoxin, induces renal toxicity and is associated with carcinogenic, teratogenic, immunotoxic, and potentially neurotoxic effects. It is linked to Balkan endemic nephropathy and classified as possibly carcinogenic to humans (group 2B) by the International Agency for Research on Cancer (IARC). The presence of OTA in animal-derived products such as meat and meat by-products is a significant public health concern, necessitating stringent monitoring to minimize risks to human exposure.
 

Mycotoxins Effects on Livestock

Cattle

Mycotoxins pose significant health risks to livestock, affecting their well-being across various species. In cattle, exposure to mycotoxins can lead to reduced feed intake, impaired growth rates, decreased milk production, and compromised immune function. Additionally, mycotoxins disrupt the rumen fermentation process, which impacts nutrient absorption and overall digestive health. This can cause digestive disturbances, such as diarrhea and acidosis, exacerbating the animal's condition and potentially leading to economic losses for farmers.
 

Swine

Swine are particularly sensitive to mycotoxins, especially toxins like deoxynivalenol (DON) and zearalenone (ZEN), which cause reproductive issues such as reduced fertility, embryonic loss, and abnormal development of reproductive organs. Contaminated feed with mycotoxins also leads to reduced weight gain, poor feed conversion efficiency, and increased susceptibility to infections in swine. Additionally, chronic exposure to mycotoxins can cause liver and kidney damage, adversely affecting the overall health and longevity of swine herds.
 

Poultry

Poultry are also susceptible to the adverse effects of mycotoxins, with aflatoxins and ochratoxins being particularly problematic. Exposure to aflatoxins in poultry can lead to reduced egg production, poor egg quality, increased mortality rates, and immune suppression. Exposure to ochratoxins can cause kidney damage and reduced growth rates, as well as impaired immune function in poultry. Additionally, the mycotoxin-contaminated feed can compromise the effectiveness of vaccination programs against diseases, increasing the risk of disease outbreaks within poultry flocks. Effective management strategies, including regular testing of feed ingredients for mycotoxins and the use of mycotoxin-binding agents, are essential to minimize the impact of mycotoxins on livestock health and productivity.
 

Mycotoxins Detection and Monitoring

Detection and monitoring of mycotoxins are crucial for ensuring food and feed safety. Currently, various methods are employed for mycotoxin detection, including immunoassays such as enzyme-linked immunosorbent assays (ELISA), chromatographic techniques like high-performance liquid chromatography (HPLC), and molecular methods such as polymerase chain reaction (PCR). These methods offer high sensitivity and specificity, allowing for accurate quantification of mycotoxins in complex matrices. Rapid screening assays provide quick results, enabling timely intervention to prevent livestock and human exposure to mycotoxins. Continuous monitoring of feed ingredients and finished feed batches is essential to detect and mitigate mycotoxin contamination effectively, ensuring the health and safety of both animals and consumers.
 

Management Strategies and Prevention Measures

In response to the growing concern over mycotoxin contamination, scientists and the feed industry are increasingly focusing on developing strategies to counteract these harmful substances. This special issue focuses on recent advancements in decontaminating common mycotoxins in feed. It includes research articles and reviews that explore various approaches, such as using novel materials or microorganisms for mycotoxin biodegradation, employing modified adsorbents to reduce mycotoxin toxicity, implementing nutritional strategies to mitigate mycotoxicosis, and understanding the mechanisms of mycotoxin toxicity to inform antidote development. Among these strategies, enzymatic degradation with products like Toxi-Free PLUS by Life Rainbow Biotech holds promise for mitigating mycotoxin contamination.
 

Method 1

Novel Adsorbents: Efforts to reduce mycotoxin contamination involve using adsorbent materials. For example, scientists have developed novel adsorbents that effectively capture mycotoxins. These adsorbents, including nanoparticles and carbon nanotubes, help to lower mycotoxin levels in feed by binding the toxins, although they do not directly affect the fungal activity.
 

Method 2

Biological Multistrategy: Biological methods incorporate a variety of strategies, including enzymatic degradation and microbial adsorption, to combat mycotoxin contamination. Certain bacteria and fungi are capable of degrading or removing mycotoxins, and enzymes like TF301 contribute to their breakdown. Notably, products such as Toxi-Free PLUS offer a multi-strategy approach that not only degrades mycotoxins but also prevents their formation. With a formulation that includes adsorbents, patented mycotoxin-degrading enzymes, and essential oils, Toxi-Free PLUS provides a comprehensive solution for controlling mycotoxins in feed.
 

Conclusion

In conclusion, mycotoxin contamination poses significant risks to livestock health and productivity, prompting the need for effective management strategies. This Special Issue highlights various approaches, including enzymatic degradation with products like Toxi-Free PLUS by Life Rainbow Biotech, novel materials, biological methods, and modified adsorbents, all aimed at mitigating mycotoxin effects in feed. With its capabilities, Toxi-Free PLUS offers a promising solution for controlling mycotoxins in livestock production. For comprehensive mycotoxin management and product inquiries, contact Life Rainbow Biotech today.



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