Effect of mycotoxins in the nutrition of farm animals

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• Effect of mycotoxins in the nutrition of farm
  animals
• secondary metabolites of fungi
• fungi start to produce them under stress
  conditions
• some of them are produced on the field (fusarium
  toxins), others during the storage (ochratoxin)
• not only mycotoxins are harmful, but also their
  metabolites, produced in their digestion and
  metabolism in the animals
• They have an influence
• on the health and immune system of the animals
• on the cell metabolism,
• the reproduction processes,
• the function of liver and kidney,
• the production traits.
• They also mean a potential food safety risk

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• Aflatoxin
• Producing
• Aspergillus flavus, A. parasiticus
• Effects
• binds to the DNA and protein of the cells,
• cause mutation, cancer, cell toxicity
• the liver is damaged first time
• The most important metabolite is aflatoxin B1
  (AFB1).
• The most dangerous toxin for both human and
  animals (excreted also in the milk)
• Produced mostly under warm temperature
  conditions
• Potential sources groundnut, soybean, corn

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• Ochratoxin
• Producing
• Aspergillus alutaceus, Penicillium verrucosum
• Effects
• inhibits the protein synthesis (PHE - tRNS)
• increase the lipid peroxidation
• decrease the cell respiration, gluconeogenezis,
  the ATP level of the cells
• damages mostly the kidney
• The more frequently produced metabolite is
  ochratoxin A (OTA).
• Produced in the storage period
• Can be found also in animal products (egg, meat,
  liver),
• potential food safety risk factor

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• Zearalenon (ZON), F-2 toxin
• Producing
• fusarium species (F. graminearum, F. culmorum, F.
  avenaceum, F. poae, F. moniliforme)
• Effects
• oestrogenic effect
• increase the plasma oestrogen level, causing
  dysfunction in reproduction
• increase the lipid peroxidation
• bleedings in the liver
• Poultry species are resistant to ZON, but causing
  serious reproduction problems in pigs, beef and
  horse.

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• Deoxynivalenol (DON, vomitoxin)
• Producing
• Fusarium species
• Effects
• inhibiting the protein synthesis and cell
  proliferation
• damages the liver fat metabolism
• decrease the success of vaccination
• stimulates the synthesis of B-limphocytes.
• Pigs refuse to eat DON contaminated diets,
• In horses it decreasing the plasma immunoglobulin
  level
• In cows decrease the milk production and milk
  fat.
• Poultry species are not so sensitive for DON

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• T-2 toxin
• Producing
• Fusarium species
• One of the most harmful toxins
• Effects
• decrease protein synthesis and cell proliferation
  
• producing lesions around the mouth
• animals refusing food intake
• poor feather production
• worse egg shell strength
• increase the lipidperoxidation in the liver
• increase the death rate after infections
• decrease milk fat

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• Fumonisins
• Producing
• Fusarium species (Fusarium moliniformin)
• Effects
• increase the weight, but decrease the fat content
  of liver
• impaired function of the immune system
• The most common form is fumonisin B1 (FB1),
• Can be found mostly in corn
• Decreasing milk production in ruminants, damages
  the liver
• Horses are especially sensitive for this toxin
  (softening of the brain, giddiness, lameness).

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• Interaction among different toxins
• Mostly more mycotoxins can be found at the same
  time.
• Their interaction depends
• on the type of toxin
• on their concentration
• on the investigated parameter
• The interaction of OTA, FB1 and DON are additive
  on the weight gain, but it is synergetic on the
  plasma asparatic acid aminotransferase enzyme.

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• Food safety aspects
• According to the investigations of Institute of
  International Cancer Research
• carcinogenic AFB1
• potential carcinogenic OTA
• probably not carcinogenic ZON, FB1, T-2
• not enough information DON, NIV
• Some of them are metabolised already in the
  enterocytes of the intestine.
• Therefore their metabolites are also important
  (ZON a-ZOL, ß-ZOL , AFB1
  AFM1)
• Absorbed quickly, after 6 hours reach their
  highest concentration in the blood.

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• Food safety aspects
• The half-life time of ZON is the longest (12-28
  hours), therefore it can be found in the egg and
  liver)
• 4-5 mg/kg of DON was not detectable from the
  tissues
• 30 mg/kg of FB1 detectable also from the kidney,
  liver and egg.
• Small concentration of OTA and T-2 toxins were
  found in eggs and other animal tissues

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• Chances to feed toxin contaminated feedstuffs
• Possibilities
• dilution with toxin free feedstuffs
• feeding with not so sensitive animal species and
  adults (beef cattle milking cow pig poultry)
• using toxin binders
• Toxin binders
• a bentonit, a zeolit, sodium-kalcium-aluminium-hy
  drosilicates, glukomannans, binders containing
  enzymes can be used efficiently (60-90) against
  AFB1
• Their affinity for fusarium toxins (ZON, DON,
  T-2) is however, poor (10-60)
• They also bind some other bioactive substances
  (vitamins, amino acids, minerals etc.)

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Effects of feeding mycotoxin contaminated diets
and different toxin binders on the weight gain of
broiler chicks

pullet
cockerel
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The weight of bursa fabricii (g)

cockerel
pullet