AQUACULTURE INFORMATION by SPECIES
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Are Fishes affected by Mycotoxins?
Mycotoxins are recognized as a global issue in agricultural production, both in livestock and aquaculture segment.
There is an increasing trend to use more and more plant ingredients in aquaculture feed caused by high prices of fishmeal and oils.
With this trend, the risk of mycotoxin contamination also increases, affecting fish growth performance as well as final product quality.
What types of mycotoxins mainly affect fish animals?
In aquaculture production,
Five most common mycotoxins
mycotoxins can cause serious
found worldwide in aquafeed
negative effects on fish and
and raw material used for feed
shrimps.
formulation:
They can be caused by one
Aflatoxins (Afla),
mycotoxin, or by their synergistic
Zearalenone (ZEN),
effects which can cause more damage, even when present in low levels.
Trichothecenes (T-2 y HT-2) Fumonisins (FUM) Ochratoxin A (OTA).
Synergism is not very well described in aquaculture. However, different studies have shown that Aflatoxin B1 (AFB1) and FUM have a synergistic effect in fish and shrimp.
Estructura molecular de la Zearalenona
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Which species are more affected?
Level of damage that
Considering this, mycotoxin risk
can be caused by the
levels for aquatic species have
mycotoxins intake depends
been considered in terms of
mainly on the type of
three categories:
toxin, its concentration in the feed and time period of exposure, as well as animal species susceptibility.
Marine species and salmonids: Trout, sea bream and sea bass Fresh warm-water fish: Tilapia, carp, channel catfish, African catfish, pangasius Shrimp: Based on studies with whitelef shrimp and tiger shrimp.
Which organs affect and which pathologies produce?
AFLATOXIN
Which organ will be affected depends exclusively on the type and amount of mycotoxin.
ZEARALENONE
TRICHOTECCENES
According to this, the target
Zearalenone is a mycotoxin
Trichoteccenes presence is
organ for Aflatoxin is liver,
which dominantly affects
related to decreased production
causing liver necrosis and liver
reproductive parameters
of bacterial cell wall breaking
carcinom.
in different aquatic species,
enzymes and decreased
causing change of relative
resistance to oxidative damage.
Beside, Aflatoxin can produce different damages and pathological manifestations such as: Small cell carcinoma
fecundicity, acceleration of sexual maturation and reducing of spawning frequency.
FUM has been generally
Abnormalities in shrimp
associated with reduced growth
OCHRATOXIN A Ochratoxin A induce mutagenic and toxic effects, degeneration of kidneys and liver and poor performances.
to in homogenous growth and physiological disorders.
FUMONISINS
Palle gills hepatopancreas.
In shrimp T-2 and HT-2 leads
rate, lower feed consumption, poor feed efficiency ratio, and impaired sphingolipid metabolism.
However, what is the most important is that ALL MYCOTOXINS are immunosuppresive, ALL MYCOTOXINS are increasing mortality and cause poor
Also cause, lesions in exocrine
productive performances.
and endocrine pancreas as well
(growth, FCR, daily intake)
in inter-renal tissue.
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With fishmeal and oil becoming
Which raw materials and other vectors are the main causes?
very expensive, the inclusion of terrestrial plant-based proteins in commercial aquaculture feeds has gained widespread acceptance. The most common plant feedstuffs used in aquafeeds are Corn Soybean meal DDGS Canola Cottonseed Peas/lupins Rice bran
Hence, these are the most
Cassava
important contaminants.
Wheat
What detection methods are used in Aquaculture to detect mycotoxins?
Mycotoxins are commonly detected and quantified in feed using antibody-based assays and chromatography techniques.
HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY (HPLC) AND GAS CHROMATOGRAPHY/MASS SPECTROMETRY (GC/MS) High-Performance Liquid
ELISA TEST
Chromatography (HPLC) and Gas Chromatography/Mass Spectrometry
Enzyme-Linked ImmunoSorbent
(GC/MS) are two of the most
Assay (ELISA) is an antibody-
widely used methods for mycotoxin
based assay that is commonly
detection and quantification.
used to detect mycotoxins. HPLC y GC/MS rAlthough, HPLC A number of commercial ELISA
and GC/MS require expensive
kits are available for Aflatoxins,
equipment and technical support
deoxynivalenol, Fumonisins,
and offer a detection limit of
Ochratoxins, and Zearalenone.
less than 0.05 ppm for many
ELISA is one of the more
mycotoxins.
affordable methods for detecting
However, the system to cover all
mycotoxins, but the detection
mycotoxins of interest and to detect
limit often exceeds 0.2 ppm for
them with the highest sensitivity,
many mycotoxins.
accuracy, and reproducibility is using LC – MS/MS. Liquid Chromatography coupled with tandem mass spectrometry (LC-MS/MS) is nowadays, “gold standard“ for mycotoxin evaluation and most reliable way for their quantification.
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How do we prevent them and/or fight against them in Aquaculture?
Management of mycotoxin
Si bien se implementan diversas
contamination and health
estrategias de mitigación de
consequences in animal
riesgos en diferentes niveles
production poses increasing
de la cadena de alimentación,
challenges to food security and
parece que los secuestrantes
end consumer safety systems.
de micotoxinas de amplio espectro tienen poca capacidad
La prevención de las micotoxinas debería comenzar con la eliminación o disminución del crecimiento de hongos en las
adsorbente en los alimentos marinos, derivando en un bajo rendimiento y menor seguridad de esos alimentos.
plantas sin olvidar el almacenaje de granos, siendo recomendable
Novel approaches in mycotoxin
utilizar inhibidores de hongos
risk management represents feed
además de controlar temperatura
additive obtained by unique,
y humedad utilizando aireación
patented technology, which is
y protegerlo contra el daño
capable to eliminated both, polar
provocado por insectos y
and less-polar mycotoxins with
roedores.
high efficiency and very quick action. This kind of products ,
A pesar de todos los esfuerzos que se hacen para reducir el nivel de micotoxinas en ingredientes y alimentos siempre existe un cierto grado de contaminación
when used as a feed additives, it minimize biological availability of mycotoxins during digestion and after fecal removal from digestive tract.
que puede llegar a representar un riesgo para el ganado.
The goal is to reduce detrimental effects of mycotoxins as well his
Complete elimination of mycotoxin contamination seems to be practically impossible.
positive impacts on growth rate, body weight and feed conversion ratio in fish and shrimp feed. A reliable way to prevent financial losses and maintain animal health.
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