From page 27
livestock farmers often find
themselves with mycotoxin
contaminated grain or feed.
Diagnosis of mycotoxicosis is
often difficult because the
effects of mycotoxins in
animals are diverse, varying
from specific to unspecific
symptoms such as immune
suppression, diarrhoea,
haemorrhages or reduced
performance.
There are nearly 400 different
mycotoxins, but there are
three types that have been
proven to be carcinogenic
(causing cancer) or toxigenic
(producing poisonous
substances).
Aflatoxins can be found in
maize, peanuts, cottonseed,
tree nuts and dairy products.
Feed concentrates and forage
can also be affected.
In all animals, aflatoxin can
cause liver damage, cancer,
decreased reproductive
performance, reduced milk or
egg production, embryonic
death, teratogenicity (birth
MYCOTOXINS
During storage, transportation and marketing, low
moisture levels should be
maintained as well.
Where you notice fodder or
defects), tumours, and
Clinical effects are enlargesuppressed immune system
ment of uterus, abortion, and hard feed that shows signs of
function, even when low
malformation of testicles and mould they should be
removed and destroyed ~
levels are consumed.
ovaries, while the viability of
and NEVER fed to livestock.
Aflatoxin generally has been
new-born animals is threatThe removal and destruction
linked to increased mortality
ened.
of debris from previous
of livestock, because it causes Mycotoxins also have an
harvests also helps.
liver damage, intestinal
immunosuppression effect,
Keeping feed fresh is
bleeding and cancer.
which means the animal is
important. Time is required
Aflatoxin B1 is the most
not able to combat other
for both mould growth and
potent carcinogen known.
diseases.
mycotoxin production to
Fumonisins affect horses, pigs There are good agricultural
occur.
and humans, through the
practices that can be impleFor feed manufacturers and
consumption of maize or
mented in the fight against
retailers, good storage space
silage.
these deadly chemicals.
is necessary, and a proper
The clinical effects are
Early or timeous harvesting
stock rotation process should
pulmonary oedema, lesions
reduces fungal infections in
be implemented to ensure
and holes in the brain,
the field. Drying of agriculoesophageal cancer, neural
tural produce to low moisture that no bags of old feed are
to be found lurking at the
tube defects, liver damage
levels helps to create less
back of the warehouse. For
and reduced growth.
favourable conditions for
the livestock owner it is
Zearalenone is found in
fungi to develop.
therefore important to have
maize, wheat, barley,
Insects help to distribute
feeds delivered often so that
sorghum substrates and hay,
fungal spores, and reduced
and pigs, sheep and dairy
moisture will also lower insect they will be fresh when used.
cattle are prone to its effects. infestation.
Continued on page 31
Diagnosis of mycotoxicosis is often difficult
because the effects of mycotoxins in animals
are diverse
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