Fumonisins DO WE KNOW THE RISKS?
Nemanja Todorović, Marko Vasiljević, Jog Raj, Hunor Farkaš, and Zdenka Jakovčević PATENT CO,. Mišićevo, Serbia
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Fumonisins are a significant health risk to livestock, and potentially also to humans There are 6 types of Fumonisins: B1, B2, B3, B4, A1 and A2
Fumonisins are naturally occurring toxins produced by several species of Fusarium fungi (molds), with
Fusarium moniliforme recognized as the largest producer of this mycotoxin. Other species such as F. proliferatum, F. nygamai, F. anthophilum, F. dlamini and F. napiforme are also producers.
Only Fumonisin B1 (FB1), B2 (FB2) and B3 (FB3) are toxicologically significant whereas the most predominant FB1 corresponds to 70% of fumonisins. In comparison to other mycotoxins, fumonisins are highly soluble and have greater capacity to spread easily and contaminate high volume of water and feedstus. FB1 is classified as a potential human carcinogen (class 2B) by International
Agency for Research on Cancer (IARC) and has been linked to acute toxicity in farm animals (horses and swine), including hepatotoxicity and nephrotoxicity.
70% -FB1
30% - Other
Raw materials affected Fungi of the Fusarium genus are FB1 and FB2 can be found as a natural contaminant
often called, field fungi. Insect
in cereals, specially corn and wheat, usually in
damage, adverse weather with
concentrations that generally induce subclinical
temperatures between 15 and 25°C and
intoxications in different species.
high contents of substrate humidity i.e. above 20% or water activity higher than 0.88 favor fumonisins production.
High humidity + Mild temperatures = Production of fumonisins
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Fusariosis Fungi of Fusarium genus are widespread worldwide and are the cause of economically significant diseases of cultivated and other plants called FUSARIOSIS. It can be found in grains e.g corn, wheat etc. In wheat, this disease can cause yield reductions of up to 70%.
Corn mycotoxins survey 2018 Fumonisins are found globally in grains and other feed materials. Recent mycotoxins survey conducted by PATENT CO shows that corn harvested around the world in 2018 and 2019 is mostly contaminated with fumonisins. In 2018 fumonisins were present in most of the samples (78%) with a median of 668 ppb and a total of 95% corn samples were contaminated with one or more mycotoxins.
yield reductions up to
70%
78%
samples contained Fumonisins
95%
corn samples were contaminated with one or more mycotoxins
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1.
ASIA
100 90
94
80 70 60
94
72
50 40 30 20 10 0
26 11
10 DON
AFB1
FB1
FB2
T-2
OTA
ZON
Fig 1: Percentage of mycotoxins detected in Asia.
2.
EUROPE 80 70
67
60 50
53
40 30
33 25
20 10
4
0 DON
AFB1
FB1
FB2
T-2
20
OTA
25
ZON
Fig 2: Percentage of mycotoxins detected in Europe.
3.
NORTH & SOUTH AMERICA
100 90
99
80 70 60
80
50 40 30 20 10
22
8
DON
AFB1
0
FB1
FB2
6
3
21
T-2
OTA
ZON
Fig 3: Percentage of mycotoxins detected in America.
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Corn mycotoxins survey 2019 Analysis of mycotoxins from corn samples in 2019 showed that 92% of the samples were contaminated
92%
with one or more mycotoxins.
samples contaminated with 1 or more mycotoxins
Fumonisins were detected in 82 % of samples, DON in 27%, AFB1 in 9%, T-2/HT-2 in 12% and ZON in 17 % of samples from the various countries.
These results demonstrate that fumonisins, type B trichothecenes and zearalenone were the predominant mycotoxins in the corn samples obtained from 2019 harvest in the different regions of the world.
FUMONISINS
82%
DON
27%
T-2/HT-2
12%
ZON
17%
AFB1
9%
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Pathogenesis The toxic effects of fumonisins are essentially the result of inhibiting sphingolipids synthesis (lipoprotein such as sphinganine and sphingosine), which controls cellular communication. The fumonisins are structurally similar to sphingosine, which forms a primary part of sphingolipids, a class of cell membrane lipids that include sphingomyelin, an important phospholipid. Fumonisins inhibit the sphinganine (sphingosine) N-acyltransferase (ceramide synthase), a key enzyme in lipid metabolism, resulting in disruption of this pathway.
This enzyme inhibition by fumonisins produces a disruption of sphingolipid metabolism resulting in increased sphinganine and sphingosine along with a decrease in complex sphingolipids in the serum and tissues of animals, which is commonly accepted as the mechanism of action for FUMONISIN toxicity in most species
(Smith et al., 2018).
Alteration of sphinganine-to-sphing osine ratio (Sa/So ratio) is used as a sensitive biomarker of fumonisins exposure.
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Fumonisins’ toxicity to animals EQUINE
The clinical signs associated
HIGH
with fumonisins’ toxicity vary significantly between species. This effect is dependent on primary target organ as safe levels of Fumonisins in feed are different
POULTRY
MEDIUM
SWINE
HIGH
for all animal species.
RUMINANTS AQUACULTURE
LOW MEDIUM
FUMONISINS ARE SEVERE IMMUNOSUPPRESSANTS AT VERY LOW CONCENTRATIONS
Typical mycotoxin induced symptoms are usually correlated with acute intoxications. However, another important fact is that Fumonisins impair immune response in many ways. Following oral intake of low amounts of these mycotoxins, firstly, the gastro-intestinal epithelial cell layer is exposed to these toxins. Fumonisins alter the different intestinal defense mechanisms including epithelial integrity, cell proliferation, and cytokine production. Since the intestinal tract is a major entrance to many enteric pathogens and their toxins, mycotoxin exposure can result in a greater susceptibility to enteric infections in animals consuming feed contaminated with these toxins. intestinal permeability by DON, T-2, FB1
cell proliferation by DON, T-2, FB1
altered cytokines production by DON, T-2, nivalenol, FB1, ZEN
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Horses – extremely sensitive Fumonisins can be extremely harmful to horses. When present in corn or other grains, fumonisins can result in moldy corn poisoning or leukoencephalmalcia. The disease syndrome was named
Leukoencephalomalacia due to the type (malacia = softening [due to necrosis]) and distribution (leuko = white matter) of the most prominent lesion in the brain. Equine are the only species in which fumonisins induce this lesion. Feed manufacturers selling corn or horse feed containing corn should Common symptoms are, horses become disoriented, walk aimlessly, circling, deranged behavior, colic, press head against solid objects, blindness, and in some cased
consider testing to ensure that the feed is safe for horses. The presence of fumonisins should alert feed manufacturers to monitor ingredients, especially corn, and evaluate the level of corn in horse feeds.
even death can occur.
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Swine
Numerous studies showed that acute fumonisins’ toxicity in
Swine chronically intoxicated with FB1 and FB2 even at low dose shows
swine is linked with pulmonary
nonspecific clinical symptoms such as reduction of daily feed
edema which generally occurs
consumption and body weight gain, lower feed conversion rate and
between 3 and 5 days after
carcass quality, associated with hepatic lesions and overall sickly
the initial consumption of
appearance of the animal..
contaminated feed. Necropsy of swine intoxicated with high doses of fumonisins have shown the occurrence of pulmonary edema which frequently evolves into hydrothorax. The lungs of pigs affected by pulmonary edema did not collapse when removed from the chest, and they increased in size with rounded edges.
D ifferen t
stadiums of pulmon ary
edema syndrome in pigs induced by fumonisins in toxication
1
2 Apathy and
Dog sitting position in
depression at the
order to relieve
beginning of clinical
pulmonary pressure
symptoms of pulmonary edema
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Cyanosis of
4
Progression of respiratory
extremities and
diculties and initiation of
progression of apathy
oral respiration
5 Death of animal due to intense pulmonary edema
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Poultry Nevertheless, of the relative resistance to fumonisins, these can still have negative effects on poultry. These negative effects can be summarized as follows:
The most important immunosuppressive effects Decreased performance
Increased kidney
(weight loss and poor
and liver weights,
feed conversion)
liver necrosis
of fumonisins in poultry are: Reduced thymus weight Reduced immunization against Newcastle disease Reduced macrophage numbers
Reduced egg
Fertility and
production
hatchability of eggs
Decreased phagocytic ability of macrophages, leading to increased susceptibility to bacterial infections
Decreased total white blood cell counts
Reduced
Low exposure levels to FB1 increased
pigmentation
sphinganine to sphingosine ratios in broiler chicks (Ledoux et al., 2003)
Induces thymic cortical thinning, mild bursal follicular atrophy and mild splenic lymphocyte depletion Decreased lymphocyte response to Salmonella gallinarum infection
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Ruminants Ruminants are
Gross and histopathological lesions, as well as
considered less
changes in serum enzymes and biochemistry indicate
sensitive than horses
an impairment of liver and possibly kidney function.
and pigs.
Although fumonisin is poorly absorbed and metabolized by cattle, it induces disturbances in the gastrointestinal tract.
Rumen motility can be slowed, due to increased exposure of the intestinal epithelium to Fumonisins and other mycotoxins.
INVISIBLE LOSSES - SUBCLINICAL EFFECTS Acute mycotoxicosis occurrences are rare events in modern livestock production. However, low mycotoxin doses, which very often not detected, are responsible for reduced efficiency of production and increased susceptibility to infectious diseases.
Nonetheless, a more likely scenario is to find mycotoxins at lower levels interacting with other stress factors leading to subclinical losses in performance, increase in incidence of disease and reduced reproductive performance. For the farmers, these subclinical losses are of greater economic importance than losses from acute effects, which are even more difficult to diagnose.
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The molds They grow on a variety of different crops and foodstuffs including cereals, nuts, spices, dried fruits, apples and coffee beans, often under warm and humid conditions. According to FAO, at least 25% of the world’s food crops are contaminated with mycotoxins, at a time when the production of agricultural commodities is barely sustainable.
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