Many species of fungi produce secondary metabolites called

mycotoxins A mycotoxin (from the Greek μύκης , "fungus" and τοξίνη , "toxin") is a toxic secondary metabolite produced by organisms of kingdom Fungi and is capable of causing disease and death in both humans and other animals. The term 'mycotoxin' ...

. These toxins can be very detrimental to both humans and animals. The side-effects of ingesting these toxic substances are called

mycotoxicosis A mycotoxin (from the Greek μύκης , "fungus" and τοξίνη , "toxin") is a toxic secondary metabolite produced by organisms of kingdom Fungi and is capable of causing disease and death in both humans and other animals. The term 'mycotoxin' ...

, which can be a variety of medical conditions. The most common fungi that produce mycotoxins include ''

Fusarium ''Fusarium'' is a large genus of filamentous fungi, part of a group often referred to as hyphomycetes, widely distributed in soil and associated with plants. Most species are harmless saprobes, and are relatively abundant members of the soil mi ...

'', ''

Aspergillus ' () is a genus consisting of several hundred mold species found in various climates worldwide. ''Aspergillus'' was first catalogued in 1729 by the Italian priest and biologist Pier Antonio Micheli. Viewing the fungi under a microscope, Miche ...

'', and ''

Penicillium ''Penicillium'' () is a genus of ascomycetous fungi that is part of the mycobiome of many species and is of major importance in the natural environment, in food spoilage, and in food and drug production. Some members of the genus produce pe ...

''. Some other fungi that are known to produce mycotoxins include '' Claviceps'' and ''

Alternaria ''Alternaria'' is a genus of Deuteromycetes fungi. All species are known as major plant pathogens. They are also common allergens in humans, growing indoors and causing hay fever or hypersensitivity reactions that sometimes lead to asthma. They ...

''.

Effects on animals

There are six known types of mycotoxins that affect animals.

Effects on feed production

The most common mycotoxin is aflatoxin. It can be very carcinogenic to both humans and animals.

Aflatoxin Aflatoxins are various poisonous carcinogens and mutagens that are produced by certain molds, particularly ''Aspergillus'' species. The fungi grow in soil, decaying vegetation and various staple foodstuffs and commodities such as hay, sweetcorn ...

is produced by two species of ''Aspergillus'', ''A. flavus'' and ''A. parasiticus'', which are known to affect plants including cereal grains, figs, nuts, and tobacco. Cereal grains are one of the main ingredient in

animal feed Animal feed is food given to domestic animals, especially livestock, in the course of animal husbandry. There are two basic types: fodder and forage. Used alone, the word ''feed'' more often refers to fodder. Animal feed is an important input to ...

. The animals most at risk of having serious problems with aflatoxins are trout, ducklings, and pigs, while cattle are less at risk. Another animal feed product is genetically altered grass and animals including cattle, sheep, and horses eat tons of it.

Ergot alkaloids Ergot ( ) or ergot fungi refers to a group of fungi of the genus ''Claviceps''. The most prominent member of this group is ''Claviceps purpurea'' ("rye ergot fungus"). This fungus grows on rye and related plants, and produces alkaloids that ca ...

are associated with grasses that are produced in a structure of ''Claviceps'' called the

sclerotia A sclerotium (; (), is a compact mass of hardened fungal mycelium containing food reserves. One role of sclerotia is to survive environmental extremes. In some higher fungi such as ergot, sclerotia become detached and remain dormant until favor ...

. Some of the conditions that result from ergot ingestion in animals include gangrene, abortion, convulsions, hypersensitivity, and

ataxia Ataxia is a neurological sign consisting of lack of voluntary coordination of muscle movements that can include gait abnormality, speech changes, and abnormalities in eye movements. Ataxia is a clinical manifestation indicating dysfunction of ...

. Fumonisins were the most recent mycotoxin found to affect humans and animals negatively. The most produced toxin for this group of fungi is fumonisin B1. Studies have shown that it can cause diseases such as equine leukoencephalomalacia in horses, hydrothorax and porcine pulmonary edema in swine, and it can negatively affect the immune system.

Mycotoxin prevention

Studies on mycotoxins show that there are three ways to preventing them from contaminating feed. The first occurs before there is a possibility of fungal infection. The second is when the fungi are starting to produce the toxins. And the final way to prevent contamination is when the material is known to be heavily infected. Other methods of prevention include planting species that are able to defend naturally against mycotoxins, proper fertilization, weed control, and proper

crop rotation Crop rotation is the practice of growing a series of different types of crops in the same area across a sequence of growing seasons. It reduces reliance on one set of nutrients, pest and weed pressure, and the probability of developing resistant ...

. The way the crops are stored after harvesting also plays an important role in staying mycotoxin free. If there is too much moisture then fungi have a better chance of growing and producing mycotoxins. Along with moisture levels, factors such as temperature, grain condition, and the presence of chemical or biologicalcan determine whether or not mycotoxin producing fungi will grow.

Decontamination of animal feed

There are several different methods being used to remove mycotoxins from feed products. One way is the use of adsorbents that bind with the mycotoxins and pull them away from the feed. Another method for decontaminating feed is with the use of

activated charcoal "Activated" is a song by English singer Cher Lloyd. It was released on 22 July 2016 through Vixen Records. The song was made available to stream exclusively on ''Rolling Stone'' a day before to release (on 21 July 2016). Background In an interv ...

in the form of a porous non-soluble powder that can bind with a variety of harmful substances. Activated charcoal is often used to remove other types of toxins or poisoning that have been ingested.

Turkey X disease

This disease was the turning point for the use of the term mycotoxin. In the 1960s, about 100,000 turkey poults died near London, England due to peanut meal that was contaminated by Mycotoxins produced by ''Aspergillus flavus''. Studies showed that the age group that was most affected was turkeys from two to twenty weeks old. Some of the first signs of Turkey X were neurological symptoms and coma, which would result in death.

References

{{Reflist Fodder Mycotoxins