Secuestrantes de Micotoxinas 11th Seminario Internacional de Ciencias Avicolas, 2016 05 11.
Trevor K. Smith, Ph.D., P.Ag., Department of Animal Biosciences, University of Guelph, Ontario, Canada.
INTRODUCTION •
•
Global climate change has resulted in unusual weather patterns. Drought, excess moisture and temperature extremes increase the chance of mycotoxin contamination of feed grains.
INTRODUCTION • Increased global trading of feed grains increases the chance that blends of grains will result in combinations of mycotoxins in a given diet.
Fusarium Mycotoxins • Aqua species, dogs, swine and horses are the most sensitive species. • Poultry are more resistant but can have altered metabolism and specific lesions. • Ruminant animals are the most resistant but effects can still be seen on reproduction and milk production.
The Fumonisins • Fumonisins can inhibit synthesis of membrane lipids. • This can result in ELEM in horses and pulmonary edema in pigs.
• The amount of fumonisin required to produce this syndrome is about 3 ppm in horses and 40 ppm in swine. • About 100 ppm causes reduced growth rate of broilers. • The greatest significance of feed-borne fumonisin likely lies in immunosuppression.
Immunosuppression and Mycotoxins • Compromised immunity is likely the greatest cause of economic losses in poultry production arising from feed-borne mycotoxins.
Immunosuppression • With immunosuppression we see lingering health problems in the flock, birds that do not respond to medications, uneven growth rates and possible failure of vaccination programs . • Increased mortalities are seen, but lesions are not classical mycotoxin lesions.
• Underestimation of mycotoxin content of feeds by conventional analytical techniques further complicates identification of the underlying causes of mortality.
The Trichothecenes • The trichothecenes are a family of more than 100 structurally-related toxins. • The trichothecenes are feed refusal toxins.
• The most common is deoxynivalenol (DON, vomitoxin). • The trichothecenes alter brain neurochemistry by increasing tryptophan and serotonin levels.
The Trichothecenes • The trichothecenes are dermal necrotic agents and inhibit cellular protein synthesis. • In poultry, the trichothecenes cause lesions in the beak and necrosis of tongue, gizzard erosion, hemorrhage of the intestinal tract, ulcers, blood in the feces, and wet, sticky litter due to nutrient malabsorption.
The Trichothecenes • The trichothecenes are immunosuppressive. • This makes birds susceptible to secondary mycotoxic diseases. • This may be due, in part, to the inhibition of immunoglobulin synthesis.
Zearalenone • Zearalenone is an estrogenic Fusarium mycotoxin. • Zearalenone can bind to estrogen binding sites and cause enlargement of the uterus and rectal and vaginal prolapse in pigs.
• Poultry are quite resistant to zearalenone toxicity. Layers can exhibit prolapse.
Fusaric Acid (5-butylpicolinic acid)
Fusaric Acid • Fusaric acid has low acute toxicity but is pharmacologically active. • Fusaric acid inhibits the enzyme dopamine-beta-hydroxylase which catalyzes the conversion of dopamine to norepinephrine. • The physiological effect of fusaric acid is a drop in blood pressure resulting in edema and poor blood flow.
Fusaric Acid • Fusaric acid also increases brain concentrations of tryptophan and serotonin. • Fusaric acid and DON act synergistically to reduce feed consumption, loss of muscle coordination and lethargy.
Fusaric Acid • Like fumonisins, DON, T-2 toxin and the balance of the trichothecenes, fusaric acid is also immunosuppressive .
Fusaric acid content of cereal grains and whole feedsa Feedstuff
Whole feeds Dry corn High-moisture corn Wheat Barley aFrom
n
8 16 4 8 2
Fusaric acid (mg/kg) 35.8 11.8 26.4 11.6 12.2
Smith and Sousadias, 1993. J. Agr. Food Chem 41:2296.
Latin American Corn • 31 samples analyzed by LC/MS/MS Jan. – Feb., 2016. • Average number of mycotoxins detected = 5.2 per sample. • Occurrence (%): AF 3, FA 90, FUM 92, DON 70.
• Average contamination (ppb): AF 120, FA 110, FUM 3,300, DON 430.
STRATEGIES FOR PREVENTING MYCOTOXICOSES • Dilution with sound grain. • Diversion to less susceptible species.
• Processing methods such as cleaning. • Physical treatments such as heat.
• Use of mold inhibitors such as propionic acid. • Use of enzymes.
• Use of mycotoxin adsorbents.
Mycotoxin Adsorbents • Mycotoxin adsorbents are nonnutritive, non-digestible and nonfermentable. • Adsorbents are high molecular weight, highly branched polymers that pass down the digestive tract intact and can adsorb small molecules including, but not exclusively, mycotoxins.
Mycotoxin Adsorbents • To be used effectively, the level of dietary inclusion of adsorbents must be appropriate for the degree of mycotoxin contamination. • Excess levels of inclusion of adsorbents can result in adsorption of nutrients such as amino acids, vitamins and minerals and digestive metabolites such as bile salts.
Inorganic Mycotoxin Adsorbents • Inorganic adsorbents are silica-based polymers. • Synthetic inorganic adsorbents include HCAS, which is specifically designed to be effective against aflatoxins.
• Natural inorganic adsorbents (clays) would include zeolites, diatomaceous earth and bentonite.
Organic Mycotoxin Adsorbents • Organic adsorbents are carbonbased polymers. • Examples would include activated charcoal, lignin and the glucomannan polymer extracted from the cell wall of yeast.
Organic Mycotoxin Adsorbents • The novelty of the yeast cell wall polymer is a high surface area which allows practical levels of inclusion (0.5 – 2.0 kg / tonne). • This minimizes the potential for adsorption of nutrients and essential intestinal metabolites.
Organic Mycotoxin Adsorbents • Another source of organic polymers is the cell wall of algae. Algae cell wall can contain cellulose, pectins, hemicelluloses, arabinogalactan proteins and lignin. • Polymers may change from cellulose to beta-mannans to beta-xylans during different life cycle phases. Domozych et al., Front. Plant Sci. 3: 82 (2012).
FEEDING BLENDS OF CONTAMINATED GRAINS Broilers: •300 7-day old Ross broilers for 42 days. •Diets contained up to 250 ppb aflatoxin with and without a yeast glucomannan adsorbent (0.05, 0.10%).
•Azizpour, A. and Moghadam, N. 2015. •Brazilian J. Poult. Sci.
Effect Of Aflatoxin On Blood Chemistry Of Broiler Chickens Parameter Liver Wt (%)
AST (u/l)
ALT (u/l)
Control
2.3c
241b
38b
Afla
5.1a
321a
53a
Afla + GM
3.5b,c
305a,b
44a,b
Afla ++ GM
2.9c
265b
42b
P
0.01
0.01
0.01
Diet
Effect Of Aflatoxin On Blood Chemistry Of Broiler Chickens Parameter Uric Acid (mg/dl)
Chol. (mg./dl)
T/G (mg/dl)
Control
7.68a
165.2
159.1a
Afla
3.65b
116.0
72.8c
Afla + GM
4.30a,b
147.1
81.2c
Afla ++ GM
6.35a
175.9
144.9a
P
0.01
NS
0.01
Diet
FEEDING BLENDS OF CONTAMINATED GRAINS Broilers: •Diets
contained up to 9.7 ppm deoxynivalenol, 15-acetyldeoxynivalenol, 20 ppm fusaric acid and 0.2 ppm zearalenone. •Swamy
et al., 2002. Poult. Sci. 81: 966-975. •Swamy
et al., 2004, Poult. Sci. 83: 533-543.
Effect Of Fusarium Mycotoxins On Body Weight Gain Of Broiler Chickens Body Weight Gain (g/bird) Diet
0-21d
21-42d
42-56d
Control
435
1683
1296
Low
376
1506
1262
High
386
1481
1316
High +
392
1534
1347
Linear
NS
0.04
NS
Effect of Fusarium Mycotoxins on Feed Consumption of Broiler Chickens Feed Consumption (g/bird) Diet
0-21d
21-42d
42-56d
Control
908
2797
2544
Low
841
2565
2437
High
923
2393
2456
High +
968
2472
2532
Linear
NS
0.05
NS
Effect of feeding blends of Fusarium mycotoxin contaminated grains on blood metabolites of broiler chickens Diet
RBC count (1012L)
Hemoglobin (ppm)
DON
FA
Polymer
<0.02
18.4
0%
2.661jk
95jl
4.7
20.7
0%
2.838j
101k
8.3
20.2
0%
2.825j
99jk
9.7
21.7
0.2%
2.541k
91l
J,k,l
Means within a column without a common superscript differ significantly (P< 0.05)
Swamy et al., 2002
Effect of feeding blends of Fusarium mycotoxin contaminated grains on blood metabolites and breast meat coloration of broiler chickens
Diet
Uric acid (umol/L)
Breast Meat Redness (Scale of 0-1)
DON
FA
Polymer
<0.02
18.4
0%
259k
0.453
4.7
20.2
0%
286jk
0.667
9.7
21.7
0%
357jk
0.804j
9.7
21.7
0.2%
281k
0.210k
l,k
Means within a column without a common superscript differ significantly (P< 0.05)
Swamy et al., 2002
Effect Of Feeding Blends Of Grains Naturally-Contaminated With Fusarium Mycotoxins On Biliary Immunoglobulin A In Finisher Broiler Chickens Biliary Immunoglobulin A (IgA)1
Diet Control
7.54a
4.7ppm DON+20.7ppm FA
7.28a
8.3ppm DON+20.2ppm FA
4.99b
9.7ppm DON+21.7ppm FA+0.2% Polymer
6.54a,b
1mm
a,b
of precipitate
Means within a column without a common superscript differ significantly (P< 0.05)
Swamy et al., 2002
FEEDING BLENDS OF CONTAMINATED GRAINS •
•
•
Broiler Breeders: Broiler breeder hens were fed a blend of contaminated wheat and corn for twelve weeks. Diets contained deoxynivalenol, fusaric acid, zearalenone and 15-acetyl DON. Yegani et al., 2006. Poult. Sci. 85: 1541
Effect Of Fusarium Mycotoxins On Performance Of Broiler Breeder Hens Egg Production (%) Diet
Month 1
Month 2
Month 3
Control
87.7a
85.3a
79.8a
Contaminated
81.3a
81.3a
78.8a
Contaminated+
86.7a
84.7a
86.7a
Effect Of Fusarium Mycotoxins On Performance Of Broiler Breeder Hens (Month 1) Shell Thickness (um)
Early Embryonic Mortality (%)
Hatch (%)
Control
32.1a
5.4a
76.5a
Contaminated
30.1b
21.5b
68.7a
Contaminated+
31.5a
2.3a
89.2a
Diet
Effect Of Fusarium Mycotoxins On Performance And Metabolism Of Laying Hens
SCWL laying hens fed blends of naturallycontaminated wheat and corn containing: DON, 15-acetyl DON, Zearalenone, Fusaric Acid. Feeding period of three months. Chowdhury and Smith. 2004. Poult. Sci. 83:1849 Chowdhury et al. 2005. Poult. Sci. 84: 1841 Chowdhury et al. 2005. Poult. Sci. 84: 1671
Effect Of Fusarium Mycotoxins On Laying Hens Feed Consumption (g/hen/d) Diet
Month 1
Month 2
Month 3
Control
119a
120a
117a
Contaminated
106b
127b
132b
Contaminated+
114a
124a
121a
Effect Of Fusarium Mycotoxins on Performance of Laying Hens Feed Efficiency (feed consumption/egg mass) Diet
Month 1
Month 2
Month 3
Control
1.88
1.92a
1.90a
Contaminated
1.94
2.29b
2.23b
Contaminated+
1.90
2.10a,b
1.94a
Effect Of Fusarium Mycotoxins on Performance of Laying Hens Egg Production (%) Diet
Month 1
Month 2
Month 3
Control
95a
90a
90
Contaminated
81b
82b
84
Contaminated+
90a
89a,b
87
Effect Of Fusarium Mycotoxins on Performance of Laying Hens Eggshell Weight (g) Diet
Month 1
Month 2
Month 3
Control
5.94a
6.19a
6.51a,b
Contaminated
5.61b
5.98a,b
6.17a
Contaminated+
5.98a
6.27a
6.44a,b
Effect Of Fusarium Mycotoxins on Performance of Laying Hens Plasma Calcium (mmol/L) Diet
Month 1
Month 2
Month 3
Control
6.93a
6.53
6.54
Contaminated
6.42b
6.50
6.49
Contaminated+
6.81a
6.96
6.88
Effect Of Fusarium Mycotoxins On Blood Chemistry Of Laying Hens Uric Acid (umol/L) Diet
Month 1
Month 2
Month 3
Control
376a
392a
390a
Contaminated
1009b
1154b
1030b
Contaminated+
499a
539a
487a
Effect Of Feeding Blends Of Grains Naturally-Contaminated With Fusarium Mycotoxins On Biliary Immunoglobulin A In Laying Hens Diet
Biliary Immunoglobulin A
Control
53.72a
Contaminated
44.08b
Contaminated+
56.34a
a,b
Means within a column without a common superscript differ significantly (P< 0.05)
Experiments With Turkeys • No. of birds: 300 poults, 5 pens of 20 poults/diet • Duration: 12 weeks
• Growth phases: Starter (0-3 wk), Grower (4-6 wk), • Developer (7-9 wk) & Finisher (10-12 wk) • Diets: – Corn-wheat-Soy (Control)
– Naturally contaminated grains (CONT) – CONT + 0.2 % Polymer
• Girish et al. (2008), Poultry Science,
Dietary mycotoxin concentrations Dietary group Starter (0-3 wk) Control CONT CONT+ GMA4 Grower (4-6 wk) Control CONT CONT+ GMA Developer (7-9 wk) Control CONT CONT+ GMA Finisher (10-12 wk) Control CONT CONT+ GMA
DON1
15-acetyl-DON
ZEN2
FA3
1.0 2.2 2.8
ND5 0.2 0.2
ND 0.2 0.2
13.1 12.4 10.2
0.5 3.3 2.7
ND 0.2 0.2
ND ND ND
7.9 18.8 8.7
1.2 3.1 2.8
ND ND ND
0.2 0.2 0.3
7.2 10.2 13.9
ND 2.9 2.6
ND ND ND
ND 0.2 0.2
5.4 12.3 12.4
Effect of dietary Fusarium mycotoxins on turkey performance Diet
0-3 wk
4-6 wk
7-9 wk
10-12 wk
Body weight gain (g/bird) Control
629
1755a
2750a
2816
CONT
600
1604b
2570b
2769
CONT + GMA
630
1761a
2713a
2861
Feed intake (g/bird/day)
Control
39
145
302
398
CONT
36
135
275
375
CONT + GMA
39
150
303
394
Feed efficiency (body weight gain/feed intake) Control
0.78
0.57
0.43
0.34
CONT
0.78
0.56
0.44
0.35
CONT + GMA
0.76
0.55
0.42
0.35
Effect of dietary Fusarium mycotoxins on the delayedtype hypersensitivity response to DNCB
(% increase in webfoot thickness)
Control
50
CONT
CONT+ GMA
a a
40 30
b a
20
ab b
10 0 24 h
48 h
72 h
Measurement Guideline
Submucosa
Villus height
Crypt depth
Muscularis
Villus width
Effects of feeding Fusarium mycotoxins on small intestinal morphology of turkeys at the end of starter phase Diet
Villus height
Starter phase (0-3wk) Control CONT CONT + GMA
968.44a 782.68b 991.28a
Control CONT CONT + GMA
448.00a 380.00b 407.25ab
Crypt depth
Villus width
(µm) Duodenum 90.49 64.65 83.98 64.46 95.40 68.44 Jejunum 70.67 66.54 73.85 62.03 73.72 67.98
Submucosa
Muscularis Villus apparent Villus to thickness surface area crypt ratio
(µm2) 20.11 105.68 15.60 106.10 17.47 117.73
62103 51953 68210
19.52 89.06 29944a 18.24 89.49 23604b 19.40 103.31 27587ab
11.14 10.01 10.94 6.54 5.63 5.81
Effects of feeding Fusarium mycotoxins on intestinal lymphocyte subset populations, cell proliferation and histological changes in turkey lymphoid organs Girish et al., Food and Chem. Toxicol. (2010) 48: 3000 - 3007
Overall Conclusions •
The feeding of grains naturallycontaminated with Fusarium mycotoxins can reduce productivity, impair reproduction and reduce health status of poultry.
•
This can result in economic losses for producers.
•
Such losses can often be prevented by the use of an appropriate mycotoxin adsorbent .
OVERALL CONCLUSIONS •
The feeding of blends of grains contaminated with Fusarium mycotoxins can alter metabolism and lower productivity of pigs and poultry.
•
This can lead to significant financial losses for producers.
•
Such losses can often be prevented by the use of an appropriate mycotoxin adsorbent.