EFFECTS OF MYCOTOXINS ON ANIMAL HEALTH AND PRODUCTIVITY
Zoila Coloma Adaniya MV. MSc. (Lima - Perú) General Manager - ZC Consulting.
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Since the first case of mycotoxicosis reported in England, in 1960, where more than 100.000 turkeys died (Austwick, 1978), the importance of mycotoxins in animal production has become clear. Currently, producers
It has been determined that
face several challenges that compromise the profitability and the growth
mycotoxins can lead to annual
of their investment.
losses of up to US$ 1.200 million (IITA, 2012), which suggests that mycotoxins can cause significant losses among productive processes and this should be assessed.
Why is it so complicated to control mycotoxins? The mechanism through which
Animal Species
mycotoxins generate their toxic effects isn’t entirely elucidated, due to their chemical structures
Age
and target organs. There can be
Productive Stage
several responses depending on:
Gender
Health Status
Additionally, different responses in individuals from the same population have been observed. Most mycotoxins can cause lipid peroxidation, damage in the function and the structural membranes of cells, and induce apoptosis. Additionally, they can
Apoptosis
also lead to immunosuppression, hyperestrogenism, hepatotoxicity, nephrotoxicity, neurotoxicity and genotoxicity (Mallmann and Dilkin, 2007; Tabbu, 2015).
Immunosuppression Hyperestrogenism Hepatotoxicity Nephrotoxicity Neurotoxicity Genotoxicity
Functional and structural damage
We know that, in natural conditions, we can find low to moderate levels of contamination, which makes it more challenging to recognize the effects associated with chronic intoxication.
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Which is the possible economic impact of mycotoxins in animal production? According to Naehrer (2012), diagnosing mycotoxicosis is hindered by the variations in symptoms, target organs, and pathological lesions. The intensity of the effects is influenced by:
Animal species: Species Age Toxin: Type of mycotoxins Level of contamination Consumption time
Gender Productive stage Health status Immunological status Nutritional status
Environmental factors: Management Biosecurity Temperature & Humidity
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Aflatoxins (AF) are considered carcinogenic, hepatotoxic, mutagenic, and
ECONOMIC IMPACT (US$) OF DIFFERENT LEVELS OF AFLATOXIN B1 IN A FLOCK OF 35,000 BROILERS UNTIL 42 DAYS OF AGE
immunosuppressive. Reports show that aflatoxins (mainly AFB1) cause complete depression of the immune system in poultry, as well as liver damage, alteration of lipid metabolism, deficient feathering, diarrhea, deficiencies in
Mycotoxin
Level (ppb)
Weight at 42 days
Total flock weight (kg)
Price per kg (US$)*
Total sales value (US$)**
2.764***
96,740
1.45
140,273
20
2.744
96,040
1.45
139,258
1,015
60
2.684
93,940
1.45
136,213
4,060
100
2.664
93,240
1.45
135,198
5,075
125
2.639
92,365
1.45
133,929
6,344
pigmentation, and loss of
Difference (US$)
weight (up to an 8%). They interfere with the synthesis of clotting factors, causing blood stains on the carcasses (Image 1), which leads to economic losses due to market
Aflatoxin B1
rejection.
Image 1. Aflatoxins alter clotting factors, causing subcutaneous haemorrhage (Source: LAMIC).
Table elaborated based on references: Mallmann (2018), Garcia (2015). *Price per kg of chicken according to the Ministry of Agriculture and Irrigation (MINAGRI). Peru, July 2018. **Dollar exchange rate according to the National Customs Authority and Tax Administration (SUNAT). Peru, July 2018. ***Average weight of males and females, according to the table Cobb 500, July 2015.
One of the effects that are frequently observed in animals that consume diets contaminated with aflatoxins is the lack of uniformity of the batches of animals
(Images 2 and 3).
IMPACT OF AFLATOXINS
It has been estimated that for every 35,000 broilers that consume feed contaminated with 20-60 ppb of AFB1,during
Image 3. Lack of uniformity in pigs that consumed feed contaminated with aflatoxins (Source: Mallmann and Dilkin, 2017).
Image 2. Lack of uniformity in broilers that consumed feed contaminated with aflatoxins (Source: LAMIC).
the production stages, there will be losses ranging from US$ 1,000 to US$ 4,000.
(Table 1). All of which without considering the logistic costs, labor costs, energy, treatments, analysis, among others.
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In 2012, Andretta et al. reported that pigs that had ingested feed contaminated with mycotoxins resulted in 21% reduction in weight gain. In this case, deoxynivalenol (DON) and aflatoxins were the mycotoxins that mostly affected the production parameters. This could result in economic losses of over 118 thousand US$ per year per 100 sows (Table 2).
Table 2 shows that, if all the weaned pigs (28) were to reach the average market weight of 117.5 Kg LW, discounting the production costs, the income per animal would be 53.8 US$. In contrast, due to the effect of the mycotoxins, they may
ECONOMIC IMPACT (US$) OF A 21% VARIATION IN WEIGHT GAIN DUE TO CONSUMPTION OF FEED CONTAMINATED WITH MYCOTOXINS IN MARKETED SOWS
Final weight (kg LW)a
Gain per animal produced (US$)b
Ganancia por cada 100 madres/año (US$)c
117.5
53.8
150,517.5
92.8*
11.6
32,480.0
Difference
118,037.5
Table elaborated based on references: Analysis of the Pork Industry in Latin America. PIC Nº 15 (2017), Andretta (2012). a = Average number of weaned piglets/sow/year based on the reference: Analysis of the Pork Industry in Latin America. PIC Nº 15 (2017). b = Average price based on the reference: Analysis of the Pork Industry in Latin America. PIC Nº 15 (2017). c = Value considering a 21% reduction on the weight gain due to the presence of mycotoxins.
only reach 79% of the average weight (92.8 Kg LW), reducing the income to US$ 11,6 per
An additional fact that is relevant about AFB1 is that, as it is
animal.
metabolized through hydroxylation, it transforms into aflatoxin M1, These changes in the zootechnical
becoming a contaminant when
parameters is associated with
excreted in milk or urine by
alterations in the gastrointestinal
animals that have ingested
tract that affect the absorption of
contaminated feed (Lee et al., 2017), making it possible to intoxicate newborn animals through milk.
nutrients, as well as the reduction of the feed ingested that can be due to the anorexic effect of DON, together with an increase of the
AFB1
AFM1
expression of pro-inflammatory cytokines and the satiety hormone (serotonin). US$ 11.6/animal US$ 53.8/animal 117.5 kg
79%
92.8 kg
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How do mycotoxins affect production systems that are free of antibiotic growth promotors (AGP)? Due to the risks associated with the inadequate use of antibiotic growth promoters, the tendency is to reduce and eventually stop their use in animal production. The gastrointestinal tract is the main entrance for most of the enteric pathogens and their toxins. AGPs are used to control the proliferation of pathogens in the intestinal tract, mainly Gram-negative bacteria such as Salmonella and E. coli. Withdrawing AGPs can increase the symptoms and susceptibility of diseases associated with the
FUSARIOTOXINS
presence of mycotoxins. Fusariotoxins, such as fumonisin and trichothecenes, mainly produced by fungi of the genus Fusarium, are capable of going through cell membranes by passive
Alteration of the intestinal barrier
Fusarium
transport, allowing them to be easily absorbed through the intestinal and integumentary systems (Middlebrook
y Leatherman, 1989; Wannemacher y Winer, 1977). Additionally, they interfere with the different defense
Easy intestinal absorption of mycotoxins (trichothecenes & fumonisins)
mechanisms of the intestinal
Immunosuppression
tract, such as the integrity of the epithelium, cell proliferation, the mucous layer, the production of immunoglobulins and cytokines, inducing immunosuppression and
Trichothecenes
Fumonisins
diminishment of the response to infections.
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It has been reported that the
Additionally, it has been
ingestion of feed contaminated
determined that pigs that
with DON predisposes to the
consume feed contaminated with
appearance of necrotic enteritis.
FB1 demonstrate more severe
In the small intestine, it can lead to a failure to digest nutrients and the leakage of plasmatic amino acids to the
lesions related to viral diseases, such as Porcine Reproductive and Respiratory Syndrome (PRRS) (Ramos et al., 2010).
intestinal lumen, providing the ideal substrate for the proliferation of C. perfringens.
FINAL CONCLUSIONS
Non-cytotoxic concentrations
Some mycotoxins are considered
of DON and toxin T-2 facilitate
to be more relevant, mainly
The new trends of AGP-free
the intestinal invasion of
due to their prevalence,
production mean that to minimize
Salmonella, increasing its passage and translocation through the intestinal epithelium (Antonissen et al., 2014).
level and harmful effects on
the risks and the possible losses they
human and animal health.
can lead to, we must become more aware of the role that mycotoxins
The negative effects produced by
have in the production process and
these toxins can be observed as a
to have stricter control over the
reduction in animal productivity,
consumables, in order to minimize
as well as a lack of response
the risks and possible losses
to vaccination programs and
that these toxins could cause.
pharmaceutical treatments.
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