Mycotoxin Symptoms – What You Should Know!

Mycotoxins are natural substances produced by moulds. All natural materials and many man-made ones are subject to contamination by moulds and under favourable environmental conditions, when temperature and moisture are conducive, these fungi proliferate and may produce mycotoxins. Over 500 mycotoxins have been identified and this number is steadily increasing. There are several different species of moulds, which generate these mycotoxins. Mycotoxins are the subsidiary metabolites as a biotic armament against other life forms.  Mycotoxin symptoms depend on the type of mycotoxin.

Origin of Mycotoxins:

1. Food and Agriculture: Agriculture has big issues with mycotoxins. Over 25% of the world's agriculture is affected by mycotoxins. Crops like corn, wheat, and peanuts are the origins for mycotoxins and these gradually end up in food. If the crops are not properly stored after harvesting, then moulds can grow and spoil the crops.
   

Types of Mycotoxin:

Below are some of the most common mycotoxin types:

1. Aflatoxins
2. Trichothecenes
3. Zearalenone
4. Ergot Alkaloids
5. Fescue toxins
6. Sporidesmin
   

Symptoms of Mycotoxins:
Mycotoxins can affect animals in a number of ways. Below are some of the mycotoxin symptoms:

• Immunosuppression: Low immunity against environmental and microbial stressors. More vulnerable to diseases.
• Decreased food consumption and dairy production (eg: milk, eggs, meat). Significant weight loss and decreased weight gain.
• Increased body temperature.
• Increased liver weight, kidney weight. Higher incidence of liver damage and cancer.
• Reproductive effects such as decreased breeding efficiency, infertility, compromised reproductive performance. Higher abortion rates and lower pregnancy rates. Birth of smaller and unhealthy calves.
• Haemorrhage, bruises and swelling of the mouth or paunch.
• Neurotoxic effects such as restlessness, anorexia, occasional convulsions, and ryegrass staggers.
• Pathological changes such as diarrhoea, lameness, necrosis of abdominal fat.

Mycotoxin Contamination in Animal Feed - The Problems and the Solutions

Mycotoxins in animal feed is a widespread problem that concerns all animal farmers. Be it stored feed grains or natural lush forage hays; Mycotoxins are everywhere. Mycotoxins are natural substances produced by moulds. All natural materials and many man-made ones are subject to contamination by moulds and under favourable environmental conditions, when temperature and moisture are conducive, these fungi proliferate and may produce mycotoxins. Over 500 mycotoxins have been identified and this number is steadily increasing. Once ingested, Mycotoxins create a combination of medical conditions in animals, which is commonly referred to as mycotoxicosis. Mycotoxicosis results in a loss of productivity, reducing the overall health of the farm animals and in case of severe infections, it can also lead to the death of the animals.

Different Animal Feed Mycotoxins And Their Effects

Moulds that grow well in natural feed crops like maize, wheat, etc. and storage grains contribute to mycotoxicosis in animals. The most common fungi producing harmful Mycotoxins are Fusarium, Aspergillus, Penicillium and Claviceps.. The various detrimental effects of the most important Mycotoxins on animals are as follows:

• Aflatoxin: Carcinogenic, causes liver cancer, liver diseases, immune suppression, etc.
• Fumonisin: Toxic effects on liver cells, toxicity in nephrons, pulmonary oedema, immune suppression, leukoencephalomalacia, etc.
• Ochratoxin: Immune suppression, frequent abortion, reduced feed intake, liver damage, nephrotoxicity, etc.
• Trichothecenes: Oedema, disrupted digestion, changes in blood circulation, reduced immunity, etc.
• Zearalenone: Frequent abortions, reduced reproductive capacity, reduced urge of copulation, atrophy conditions in both male and female gonads, oestrogenic disorders.
• Ergot alkaloids: Disrupted nervous system, suppressed immune responses, gangrenous syndrome, etc.
  

Both forage grass and feed grain can be contaminated with major Mycotoxins and after ingestion create the above-mentioned clinical conditions in animals.

Mycotoxicosis prevention methods:

As more than 500 known Mycotoxins naturally occur in farms and are often masked with sugar molecule bonding, sampling methods often fail to resolve the Mycotoxin contamination issues. Modern scientific approaches to mycotoxicosis prevention adapt two more significant feed additives that can either render the toxins harmless or control Mycotoxin production. These methods are as follows:

• Mycotoxin inhibitors: These compounds are harmless to the animals but when these are added to animal feed can significantly control mold growth and hence stop new Mycotoxin production.
• Mycotoxin adsorbents: Usually aluminosilicates or yeast cell wall derivatives are used to bind with already present Mycotoxins converting them into harmless complexes.
  

Apart from these methods, weed control, crop rotation, proper storage methods can also help in stopping Mycotoxin contamination.

Things You Need To Know About Storage Mycotoxin

Mycotoxins are a common problem on farms, and are natural substances produced by moulds. All natural materials and many man-made ones are subject to contamination by moulds and under favourable environmental conditions, when temperature and moisture are conducive, these fungi proliferate and may produce mycotoxins. Over 500 mycotoxins have been identified and this number is steadily increasing.

The impact of these Mycotoxins however can be severe on cattle, pigs, horses, poultry and fish. Moulds grow well on both forage and grains before they are harvested. Mycotoxin inhibitors can control the new fungal growth in crops. But that does not put an end to mould contamination as Storage Mycotoxins are very common in animal feed that is stored after the crop harvest. There are several reasons behind the growth of moulds and related Mycotoxins in a storage environment.

Factors promoting Mycotoxin contamination in storage feed:

• Poor drying conditions and the presence of more than 12% - 15% air moisture.
• Poor sealing and packaging.
• Delayed sealing of foraging and feed grain materials.
• Cold damp temperatures.
• Shady poor storage areas.
• Delayed harvesting of field crops.
• Silages.
• Well aerated atmosphere.
  

Types of storage moulds and related Mycotoxins:

The two most common storage fungi are Aspergillus and Penicillium. These moulds are tolerant to acids and they frequently occur in silages. There are several species related to these two moulds that produce toxic secondary metabolites known as Mycotoxins that commonly contaminate feed grains and foraging materials.

• The Mycotoxins produced by Aspergillus are - Aflatoxin, Fumitoxins, Ochratoxins, Cyclopiazonoic acid, Gliotoxin, Sterigmatocystin, Fumitremorgens etc. All the toxins can be found in great numbers in contaminated storage grains.  Aflatoxin deserves a special mention as it is the most common and it is heavily carcinogenic and can cause many issues within farm animals.
• The Mycotoxins produced by Penicillium are - Ochratoxin, Citrinin, Patulin, PR toxin, Roquefortin C, Penetrem, Mycophenolic acid, etc. Among these Ochratoxin, PR toxin and Patulin are the most common.
  

Clinical symptoms of storage toxin contamination:

• In the case of Aflatoxin: Reduced milk production, reduced immune responses, reduction in rumen motility, damaged liver (can even lead to hepatic cancer), frequent abortions, etc.
• In the case of Ochratoxins: Easily absorbed by the animal gut this Mycotoxin reduces protein synthesis in the animal’s body, effects the immune system adversely, affects kidneys, reduces normal enzyme actions, reduces cellular respiration, causes abortions and can even lead to cancer.
• In the case of PR toxins: Disturbs rumen homeostasis, retained placental conditions with frequent abortions, reduces normal feed intake, lethargy, irritation and inflammation of gut, etc.
  

In the case of Patulin: Reduced rumen function, reduced digestive capacity, carcinogenic and death.