A Targeted Approach to Mycotoxin Management in Poultry

2nd March 2022

According to the Intergovernmental Panel on Climate Change (IPCC) increasing global temperatures and CO2 levels are factors that could enhance and promote the growth of mycotoxins in crops and increase prevalence of contamination.

As well as this, animal feed formulators are being put under increasing pressure to formulate with alternative ingredients in the coming months due to changes in demand and availability as well as price fluctuations of more conventional ingredients. These changes could enhance the challenges facing producers in how to best prevent, diagnose and treat mycotoxin contamination in their flocks.

What are Mycotoxins?

Mycotoxins are toxic substances produced by moulds as they mature. Mould growth can be found in all types of crops and feed materials and can occur before harvest and after harvest, during storage, and/or on the feed itself often under warm, damp and humid conditions. Concerningly, most mycotoxins can survive food processing remaining toxic to the humans and animal that may ingest them, causing ill health referred to as "mycotoxicosis".

Several hundred different mycotoxins have been identified globally, with trends in terms of where they are located. However, the most commonly observed mycotoxins that present a concern to poultry include Aflatoxins, Ochratoxin A, Fumonisins, Zearalenone and Deoxynivalenol.

Production is dependent on climate

Figure 1. Map showing preferred climate regions of Fusarium and Aspergillus moulds which are responsible for producing Aflatoxins, Deoxynivalenol, T2 and Zearalenone toxins.

Feed samples are constantly being analysed to detect mycotoxin contamination. In some studies, up to 95% of the samples tested contain at least one mycotoxin. Worldwide, it is common to find samples with 3 or more mycotoxins.

The impact of mycotoxins in poultry

With risk of mycotoxin contamination ever present across the global supply chain, it is important to understand them and how they impact poultry production. When many different mycotoxins are present together, synergistic and additive effects increase their potential of causing ill-health for the animal.

Symptoms of mycotoxin exposure are varied. There is no one symptom of mycotoxicosis and all symptoms may be attributed to different causes. However, the more symptoms animals are showing, the more likely it is that mycotoxins are the cause. Common symptoms of mycotoxicosis in poultry include feed refusal, oral lesions, poor growth rate, fatty liver and kidney damage, diarrhoea and reduced egg numbers and poorer quality eggs.

Combined these symptoms will reduce bird performance and impact upon overall producer margins.


Aflatoxins have a particularly negative impact on the function of the liver and kidney, as well as altering the immune function, and impairing protein synthesis. This can affect weight gain, feed efficiency and mortality. Carryover into meat and eggs is possible with high or chronic intake of the toxin.

They are the main mycotoxin concern for South Asia due to the high temperatures and humidity in the region. Aspergillus moulds are commonly found infecting energy and protein rich commodities such as maize and rice. Management strategies, such as the use of mould inhibitors for stored grain and toxin binders in feed, are necessary in this area to keep animals healthy and productive.


Fumonisins are produced by Fusarium species, usually on grains such as wheat and barley and are of particular concern for Latin America but are highly prevalent around the globe. They can disrupt gut health even at very low levels as their absorption interacts with other toxins and interferes with gut bacteria, including those affecting immunity. As a result, lower productivity is expected in animals exposed to even low levels of this toxin.


Deoxynivalenol (DON) is highly prevalent across the globe and has a multitude of toxic effects in animals. In poultry, it is related to gut lesions and alterations in the immune response which leads to lower productivity and feed efficiency. DON is also known as vomitoxin, as it causes nausea and loss of appetite. This can result in feed refusal and reduced daily weight gain. In laying flocks, this can result in fewer, lower quality eggs.


T2 is extremely detrimental for poultry producers. It is a potent inhibitor of protein synthesis, which affects the lining of the gastrointestinal tract, skin, and immune cells. The consequences include poor weight gain, diarrhoea, skin and beak lesions, and decreased production.


Zearalenone (ZON) is produced by Fusarium species and can be found on wheat and grain forming moulds. In some studies, more than 80% of all samples tested for ZON came back positive. It is linked with immune cell and organ damage in animals, as it causes alterations in cells. ZON also mimics oestrogen and so is related to reproductive issues such as fertility, egg shell thickness, and hatchability.

Ochratoxin A

Poultry are at greater risk from Ochratoxin A (OTA) than other mycotoxins. It leads to impaired feed conversion and poor egg shell quality as well as being particularly detrimental to kidney function. It has also been shown to carry over into the meat making it dangerous for human consumption.

Multiple mycotoxins can co-occur and certain combinations are known to have synergistic or additive effects, aggravating their adverse impacts on both animal and human health.

Impacting performance even at "safe" levels

As a specialist in sustainable food solutions, Devenish leads pioneering science-based research and development that focuses on improving animal health and welfare. Research conducted by Devenish in partnership with the Institute of Global Food Security at Queen's University Belfast, was published in Toxins Journal. This innovative longitudinal three-year study found that even low levels of mycotoxins, below EU regulatory levels, have a direct negative impact on bird performance. The study showed a variation in FCR across the crops by as much as 14 points, resulting in a significant impact on bird performance and profitability. This type of research indicates the need to update the current regulations with the possible adoption of lower limits.

For more information on this study, watch our video below.

Researching Mycotoxins with Queen's & Devenish from Devenish on Vimeo.

It is imperative that formulators try and lessen the potential negative impacts for their producers by including mycotoxin binders in their diet formulations. It is a good idea to use a species-specific deactivator, like Devenish's SmartShield AV to reduce the negative effects of mycotoxins unique to poultry production systems. It can maintain and improve growth rate in broilers, egg production and quality in layers and reproductive performance in breeding stock. A species-specific deactivator, such as SmartShield AV, can also reduce the risk of transfer of mycotoxins to eggs in breeding birds preventing subsequent harm to progeny as well as supporting the animals natural defence against mycotoxins.

If you would like to know more about how SmartShield can reduce the negative impact of mycotoxin of your birds, please click here or contact your local Devenish representative.

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