Mycotoxins in livestock systems in
developing countries
Johanna Lindahl1,2,3 & Delia Grace1
1International Livestock Research Institute, Nairobi, Kenya; 2Uppsala University, Uppsala, Sweden
3Swedish University of Agricultural Sciences, Uppsala, Sweden
World Mycotoxin Forum, Belfast, Northern Ireland, 14–16 October 2018
Presentation outline
• Mycotoxins and livestock in low and middle-
income countries (LMIC)
• Our work in Africa
• What do we do about it?
• Mitigation strategies at different levels in Kenya
Aflatoxins are a global issue
CGIAR are global institutes
International
Center for Tropical
Agriculture (CIAT)
International
Crops Research
Institute for the
Semi-Arid Tropics
(ICRISAT)
International
Institute of Tropical
Agriculture (IITA)
International
Livestock Research
Institute (ILRI)
International
Maize and Wheat
Improvement
Center (CIMMYT)
International Food
Policy Research
Institute (IFPRI)
Why focus on aflatoxins in Kenya?
• Kenya outbreak 2004-2005 125 known fatal
cases
• 884 women sampled in Eastern Province
• All had aflatoxin in the blood
• Exposure levels higher in poor people
Why bother about aflatoxins and animals?
• Animals are susceptible to aflatoxins: some more,
some less
1. Animal suffering- an animal welfare issue
2. Reduced animal productivity
3. Aflatoxins in animal-source foods
Health effects observed
• Liver damage
• Gastrointestinal dysfunction, decreased appetite
• Immunosuppression
• Decreased reproductive function, decreased
growth, and decreased production
• Can we see these effects in low-producing
animals?
• Little research in Africa in literature search
• Varying effects in all studies
Highly susceptible: oral LD50 (<1 mg per kg body weight)
Rabbits, ducks, cats, swine, rainbow trout
Moderately susceptible: oral LD50 (1-2 mg per kg body weight)
Dogs, horses, calves, turkeys, guinea pigs, sheep, baboon
Relatively resistant: oral LD50 (5-10 mg kg body weight)
Chickens, rats, macaque monkeys, mouse, hamsters
One teaspoon of aflatoxin is enough to kill 2,500 rabbits
Safe levels?
• ≤50 in young poultry
• ≤100 in adult poultry
• ≤50 in weaned pigs
• ≤200 in finishing pigs
• <100 in calves
• <300 in cattle
• <100 in Nile tilapia
However depending on other factors!
Interactions
Mycotoxin Main fungi Impact on animal health
Aflatoxins Aspergillus spp All livestock susceptible to different
degrees.
Acute toxicity, hepatotoxic and
nephrotoxic. Carcinogenic and mutagenic.
Growth impairment. Immunosuppression.
Ochratoxin A Aspergillus spp,
Penicillum spp
Nephrotoxic
Immunosuppression
Possibly carcinogenic
Fumonisins Fusarium spp Toxic to liver and central nervous system
Possibly carcinogenic
Zearalenone Fusarium spp Swine highly sensitive, cattle less sensitive.
Endocrine disruption. Estrogenic effects,
reduced reproduction, feminisation,
malformations.
Trichotecenes Fusarium spp Gastrointestinal disturbance. Reduced feed
intake. Ill-thrift. Immunosuppression.
Animal source food
• Aflatoxins are transferred to animal products
• 1-7% of aflatoxins in feed is metabolized and
transferred to milk
• Much lower transfer to meat and eggs
• Reduced if stop feeding
Farmer Consumer
Economic
flow
Aflatoxin
flow
Human
exposure
Feed
produce
r
AB1
AB1
AB1-> AM1
AM1
Corn/feed
produced
at farm
Corn/feed
purchased
Milk produced
at farm
AB1 AM1
Treatments
Feed
seller Farmer
Veterinary services
Milk
retailer
Agricultural services
Consumer
Aflatoxins in Kenya dairy
Qualitative study- understanding behaviour
• Women greater role in deciding what to feed cattle
• Common to feed mouldy food to livestock
• Women more likely to report taste of maize as an indicator of
moulds
• Men and women share more decision making than literature
suggests
• Men and women disagree which gender has responsibility
Kenya- dairy value chain
• Feed collected from 5 countiesa
– From farmers: 0.02 ppb to 9,661ppb
– Samples exceeding 5ppb
• 25% to 100% of the feed in farms
• 85.7% to 100% of the feed from feed retailers
• 20% to 100% of the feeds from feed manufacturers
• Milk samples: Up to 6999ppt
a Mugangai et al. 2016
One year survey
0
50
100
150
200
250
300
1 2 3 4 5 6 7 8 9 10 11 12
dagoretti
Westlands
24 samples per month
Dagoretti: low-income area
Westlands: High-income area
One year survey
0
200
400
600
800
1000
1200
Pasteurized Boiled Pasteurized Raw UHT Pasteurized
Lala Milk Yoghurt
Average of ppt
Max of ppt
Producer Number Mean price
KES/litre
(range)
Mean aflatoxin
M1 levels
(ng/kg)
Standard
deviation Min Max
Geometric
mean
Farmers 75 65 (45-110) 116.5 153.3 <LOD 1069.5 65.6 a
Company A 74 155 (80-610) 57.0 43.9 7.6 272.3 46.4
Company B 12 101 (90-120) 296.9 206.1 59.0 743.3 226.9
Company C 51 128 (60-233) 37.2 33.9 <LOD 166.1 22.7 b
Company D 37 125 (86-233) 38.9 33.5 <LOD 156.1 23.7 b
Others 42 176 (76-660) 111.3 169.9 7.3 1078.5 68.0 a
Table 2. Aflatoxin M1 levels in milk samples of different origins purchased in Nairobi, Kenya
Geometric means with the same superscript were not significantly different
LOD: Limit of detection (2 ng/kg)
Kenya- urban milk
• Milk collected from informal milk retailers
– 58% knew about aflatoxin, but only 6% thought
milk was not totally safe after boiling
– Milk samples: mean AFM1 was 128.7 ppt, up to
1675 ppt. 55% of samples exceeded 50 ppt and
6% 500 ppt
– Women consume 1 litre per day!
Kiruni et al. 2016, Afr J Food, Nutr Ag Dev
Kenya- urban milk
• Child exposure study
• Korogocho & Dagoretti
• 41% of children were stunted
• 98% of foods contained aflatoxin
• 100% of milk contained AFM1
• AFM1 exposure associated with decreased Height for
Age score
Kiarie et al. 2016, Afr J Food, Nutr Ag Dev
27%
59%
14%
moderate stunted
Normal
severe stunted
Urban consumers
Completed and results
Willingness to pay study: 600 consumers
• Dagoretti:
• 55% know of aflatoxin (45% of these believe it can be
transferred to milk)
• 53% think aflatoxin is a serious threat.
• CBD and Westlands:
• 80% know of aflatoxin (51% of these believe it can be
transferred to milk)
• 32% think aflatoxin is a serious threat
• All income willing to pay a premium aflatoxin
assured milk
Ethiopia dairy value chain
• Milk
– 26% exceeded 500 ppt
– Max 4980 ppt
• Feed
– 90% above 10 ppb
– Max 419 ppb
• Feeding noug cake increased AFM1 levels in
milk
Senegal- dairy value chain
• Feed and milk- under analysis
– Feed: highest levels in concentrate 305 ppb
– Milk: Mean 205 ppt, max 1000 ppt
Uganda pigs
Feed Mean ppb Max ppb
Commercial feeds 27 64
Cottonseed 65 134
Maize bran 57 118
Silage 22 48
Silverfish 15 23
34 out of 728 urine samples > 20 ppb
Vietnam pigs
• 1920 pigs screened for aflatoxins in urine at
slaughter
• 54% positive
• AFB1 in maize: 29% above 5 ppb, max 35 ppb
• Low knowledge, most maize for animal feed
• Where does the aflatoxin come from?
Mitigation options
• Aflatoxins can be mitigated all along the dairy
value chain
Costs
Implementation
Side effects
Farmer Consumer
1. Stop aflatoxin production
Aflatoxin
flow
Human
exposure
AB1
AB1
AB1-> AM1
AM1
Corn/feed
produced
at farm
Corn/feed
purchased
Milk produced
at farm
AB1 AM1
On the field- storage
• Improved varieties- more resistant crops
• Bio control: AflaSafe™, AflaGuard™
• Improved drying
• Improved storage
• Good Agricultural Practices, GAP
Reduces aflatoxins for both humans and
animals
Costly?
Farmer Consumer
2. Stopping the bad feed
Aflatoxin
flow
Human
exposure
AB1
AB1
AB1-> AM1
AM1
Corn/feed
produced
at farm
Corn/feed
purchased
Milk produced
at farm
AB1 AM1
Objectives of feed standards
1. Protect humans from harmful aflatoxins in animal source foods
2. Safeguard the benefits people derive from livestock
3. Protect value chain actors from bad products
4. Encourage fair trade, and economic growth through promoting
standards and credibility
2. Stopping the bad feed
• Feed regulations
Implementation
What do you do with illegal feed?
Costs?
• Market incentives
Poor people?
Not sustainable
Farmer Consumer
3. Within the cow
Aflatoxin
flow
Human
exposure
AB1
AB1
AB1-> AM1
AM1
Corn/feed
produced
at farm
Corn/feed
purchased
Milk produced
at farm
AB1 AM1
Binder
Standards for Anti-Mycotoxin Additives (AMAs) in Feeds
Clays (aluminosilicates)
• Most effective binder but different clays
vary in effectiveness. Up to 90%
reduction.
Yeast/bacterial cell wall extracts
• Provide other useful nutrients, but
evidence on effectiveness is mixed
Other binders
• Some are promising but less evidence of
effectiveness
The case for binders
• Multiple benefits:
1. Increase animal productivity
2. Reduce aflatoxins in animal-source foods
3. Create safe “sink” for aflatoxin
4. Improved animal welfare
• Food safety/security tradeoff  win-win opportunity
• Current trial will provide evidence on effectiveness
Reducing aflatoxins in milk using binders
• Baseline survey to collect data on:
– Levels of aflatoxins in milk
– Feeding practices
– Farmer awareness
– Farmer willingness to use mitigation methods
– Farmer willingness to pay for binders or other
mitigation methods
Study sites
• Urban/Peri-urban
– Kasarani
– Kisumu
• 20 trial farms and 10 control farms recruited
in each site
– Given Novasil as a feed additive
Follow up
• Regular follow up and endline survey of farmers
• Preliminary results:
• High dosing of binder reduces aflatoxin
• Farmers perceive improved production
• Compliance?
• Concerns with adulteration
Farmer Consumer
4. In the milk?
Aflatoxin
flow
Human
exposure
AB1
AB1
AB1-> AM1
AM1
Corn/feed
produced
at farm
Corn/feed
purchased
Milk produced
at farm
AB1 AM1
4. In the milk
• Biological control??
Research still ongoing
Pasteurization not working
Farmer Consumer
5. Stopping consumption of contaminated milk
Aflatoxin
flow
Human
exposure
AB1
AB1
AB1-> AM1
AM1
Corn/feed
produced
at farm
Corn/feed
purchased
Milk produced
at farm
AB1 AM1
5. Stopping consumption
• Legislation
• Awareness and market incentives
Implementation
What do you do with illegal milk?
Costs?
Poor consumers?
The challenge
Change:
To:
Food
safety
Food
security
Improved
food
security
Improved
food
safety
Better
health
Take home messages
• Livestock is affected by aflatoxins, and so are animal-
sourced food
• Livestock feed sector + binders can suck
contaminated grain out of human food chain
• Potential for regulation to cause harm (burden on
agricultural sector, concentrating contaminated
among poorest)
• Need to research what works in each country
Conclusions
There is no silver bullet to eradicate aflatoxins
Animals may be both part of the problem and part
of the solution
The Kenya work is financed by the Ministry of Foreign
Affairs, Finland in partnership with the International Food
Policy Research Institute (IFPRI), Luke Finland and the
Biosciences in eastern and central Africa–International
Livestock Research Institute (BecA-ILRI) hub
It contributes to the CGIAR Research Program on
Agriculture for Nutrition and Health
Acknowledgements
The presentation has a Creative Commons licence. You are free to re-use or distribute this work, provided credit is given to ILRI.
better lives through livestock
ilri.org

Mycotoxins in livestock systems in developing countries

  • 1.
    Mycotoxins in livestocksystems in developing countries Johanna Lindahl1,2,3 & Delia Grace1 1International Livestock Research Institute, Nairobi, Kenya; 2Uppsala University, Uppsala, Sweden 3Swedish University of Agricultural Sciences, Uppsala, Sweden World Mycotoxin Forum, Belfast, Northern Ireland, 14–16 October 2018
  • 2.
    Presentation outline • Mycotoxinsand livestock in low and middle- income countries (LMIC) • Our work in Africa • What do we do about it? • Mitigation strategies at different levels in Kenya
  • 3.
    Aflatoxins are aglobal issue
  • 4.
    CGIAR are globalinstitutes International Center for Tropical Agriculture (CIAT) International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) International Institute of Tropical Agriculture (IITA) International Livestock Research Institute (ILRI) International Maize and Wheat Improvement Center (CIMMYT) International Food Policy Research Institute (IFPRI)
  • 5.
    Why focus onaflatoxins in Kenya? • Kenya outbreak 2004-2005 125 known fatal cases • 884 women sampled in Eastern Province • All had aflatoxin in the blood • Exposure levels higher in poor people
  • 6.
    Why bother aboutaflatoxins and animals? • Animals are susceptible to aflatoxins: some more, some less 1. Animal suffering- an animal welfare issue 2. Reduced animal productivity 3. Aflatoxins in animal-source foods
  • 7.
    Health effects observed •Liver damage • Gastrointestinal dysfunction, decreased appetite • Immunosuppression • Decreased reproductive function, decreased growth, and decreased production • Can we see these effects in low-producing animals? • Little research in Africa in literature search • Varying effects in all studies
  • 8.
    Highly susceptible: oralLD50 (<1 mg per kg body weight) Rabbits, ducks, cats, swine, rainbow trout Moderately susceptible: oral LD50 (1-2 mg per kg body weight) Dogs, horses, calves, turkeys, guinea pigs, sheep, baboon Relatively resistant: oral LD50 (5-10 mg kg body weight) Chickens, rats, macaque monkeys, mouse, hamsters One teaspoon of aflatoxin is enough to kill 2,500 rabbits
  • 9.
    Safe levels? • ≤50in young poultry • ≤100 in adult poultry • ≤50 in weaned pigs • ≤200 in finishing pigs • <100 in calves • <300 in cattle • <100 in Nile tilapia However depending on other factors!
  • 10.
    Interactions Mycotoxin Main fungiImpact on animal health Aflatoxins Aspergillus spp All livestock susceptible to different degrees. Acute toxicity, hepatotoxic and nephrotoxic. Carcinogenic and mutagenic. Growth impairment. Immunosuppression. Ochratoxin A Aspergillus spp, Penicillum spp Nephrotoxic Immunosuppression Possibly carcinogenic Fumonisins Fusarium spp Toxic to liver and central nervous system Possibly carcinogenic Zearalenone Fusarium spp Swine highly sensitive, cattle less sensitive. Endocrine disruption. Estrogenic effects, reduced reproduction, feminisation, malformations. Trichotecenes Fusarium spp Gastrointestinal disturbance. Reduced feed intake. Ill-thrift. Immunosuppression.
  • 11.
    Animal source food •Aflatoxins are transferred to animal products • 1-7% of aflatoxins in feed is metabolized and transferred to milk • Much lower transfer to meat and eggs • Reduced if stop feeding
  • 12.
    Farmer Consumer Economic flow Aflatoxin flow Human exposure Feed produce r AB1 AB1 AB1-> AM1 AM1 Corn/feed produced atfarm Corn/feed purchased Milk produced at farm AB1 AM1 Treatments Feed seller Farmer Veterinary services Milk retailer Agricultural services Consumer
  • 13.
    Aflatoxins in Kenyadairy Qualitative study- understanding behaviour • Women greater role in deciding what to feed cattle • Common to feed mouldy food to livestock • Women more likely to report taste of maize as an indicator of moulds • Men and women share more decision making than literature suggests • Men and women disagree which gender has responsibility
  • 14.
    Kenya- dairy valuechain • Feed collected from 5 countiesa – From farmers: 0.02 ppb to 9,661ppb – Samples exceeding 5ppb • 25% to 100% of the feed in farms • 85.7% to 100% of the feed from feed retailers • 20% to 100% of the feeds from feed manufacturers • Milk samples: Up to 6999ppt a Mugangai et al. 2016
  • 15.
    One year survey 0 50 100 150 200 250 300 12 3 4 5 6 7 8 9 10 11 12 dagoretti Westlands 24 samples per month Dagoretti: low-income area Westlands: High-income area
  • 16.
    One year survey 0 200 400 600 800 1000 1200 PasteurizedBoiled Pasteurized Raw UHT Pasteurized Lala Milk Yoghurt Average of ppt Max of ppt
  • 17.
    Producer Number Meanprice KES/litre (range) Mean aflatoxin M1 levels (ng/kg) Standard deviation Min Max Geometric mean Farmers 75 65 (45-110) 116.5 153.3 <LOD 1069.5 65.6 a Company A 74 155 (80-610) 57.0 43.9 7.6 272.3 46.4 Company B 12 101 (90-120) 296.9 206.1 59.0 743.3 226.9 Company C 51 128 (60-233) 37.2 33.9 <LOD 166.1 22.7 b Company D 37 125 (86-233) 38.9 33.5 <LOD 156.1 23.7 b Others 42 176 (76-660) 111.3 169.9 7.3 1078.5 68.0 a Table 2. Aflatoxin M1 levels in milk samples of different origins purchased in Nairobi, Kenya Geometric means with the same superscript were not significantly different LOD: Limit of detection (2 ng/kg)
  • 18.
    Kenya- urban milk •Milk collected from informal milk retailers – 58% knew about aflatoxin, but only 6% thought milk was not totally safe after boiling – Milk samples: mean AFM1 was 128.7 ppt, up to 1675 ppt. 55% of samples exceeded 50 ppt and 6% 500 ppt – Women consume 1 litre per day! Kiruni et al. 2016, Afr J Food, Nutr Ag Dev
  • 19.
    Kenya- urban milk •Child exposure study • Korogocho & Dagoretti • 41% of children were stunted • 98% of foods contained aflatoxin • 100% of milk contained AFM1 • AFM1 exposure associated with decreased Height for Age score Kiarie et al. 2016, Afr J Food, Nutr Ag Dev 27% 59% 14% moderate stunted Normal severe stunted
  • 20.
    Urban consumers Completed andresults Willingness to pay study: 600 consumers • Dagoretti: • 55% know of aflatoxin (45% of these believe it can be transferred to milk) • 53% think aflatoxin is a serious threat. • CBD and Westlands: • 80% know of aflatoxin (51% of these believe it can be transferred to milk) • 32% think aflatoxin is a serious threat • All income willing to pay a premium aflatoxin assured milk
  • 21.
    Ethiopia dairy valuechain • Milk – 26% exceeded 500 ppt – Max 4980 ppt • Feed – 90% above 10 ppb – Max 419 ppb • Feeding noug cake increased AFM1 levels in milk
  • 22.
    Senegal- dairy valuechain • Feed and milk- under analysis – Feed: highest levels in concentrate 305 ppb – Milk: Mean 205 ppt, max 1000 ppt
  • 23.
    Uganda pigs Feed Meanppb Max ppb Commercial feeds 27 64 Cottonseed 65 134 Maize bran 57 118 Silage 22 48 Silverfish 15 23 34 out of 728 urine samples > 20 ppb
  • 24.
    Vietnam pigs • 1920pigs screened for aflatoxins in urine at slaughter • 54% positive • AFB1 in maize: 29% above 5 ppb, max 35 ppb • Low knowledge, most maize for animal feed • Where does the aflatoxin come from?
  • 25.
    Mitigation options • Aflatoxinscan be mitigated all along the dairy value chain Costs Implementation Side effects
  • 26.
    Farmer Consumer 1. Stopaflatoxin production Aflatoxin flow Human exposure AB1 AB1 AB1-> AM1 AM1 Corn/feed produced at farm Corn/feed purchased Milk produced at farm AB1 AM1
  • 27.
    On the field-storage • Improved varieties- more resistant crops • Bio control: AflaSafe™, AflaGuard™ • Improved drying • Improved storage • Good Agricultural Practices, GAP Reduces aflatoxins for both humans and animals Costly?
  • 28.
    Farmer Consumer 2. Stoppingthe bad feed Aflatoxin flow Human exposure AB1 AB1 AB1-> AM1 AM1 Corn/feed produced at farm Corn/feed purchased Milk produced at farm AB1 AM1
  • 29.
    Objectives of feedstandards 1. Protect humans from harmful aflatoxins in animal source foods 2. Safeguard the benefits people derive from livestock 3. Protect value chain actors from bad products 4. Encourage fair trade, and economic growth through promoting standards and credibility
  • 30.
    2. Stopping thebad feed • Feed regulations Implementation What do you do with illegal feed? Costs? • Market incentives Poor people? Not sustainable
  • 31.
    Farmer Consumer 3. Withinthe cow Aflatoxin flow Human exposure AB1 AB1 AB1-> AM1 AM1 Corn/feed produced at farm Corn/feed purchased Milk produced at farm AB1 AM1 Binder
  • 32.
    Standards for Anti-MycotoxinAdditives (AMAs) in Feeds Clays (aluminosilicates) • Most effective binder but different clays vary in effectiveness. Up to 90% reduction. Yeast/bacterial cell wall extracts • Provide other useful nutrients, but evidence on effectiveness is mixed Other binders • Some are promising but less evidence of effectiveness
  • 33.
    The case forbinders • Multiple benefits: 1. Increase animal productivity 2. Reduce aflatoxins in animal-source foods 3. Create safe “sink” for aflatoxin 4. Improved animal welfare • Food safety/security tradeoff  win-win opportunity • Current trial will provide evidence on effectiveness
  • 34.
    Reducing aflatoxins inmilk using binders • Baseline survey to collect data on: – Levels of aflatoxins in milk – Feeding practices – Farmer awareness – Farmer willingness to use mitigation methods – Farmer willingness to pay for binders or other mitigation methods
  • 35.
    Study sites • Urban/Peri-urban –Kasarani – Kisumu • 20 trial farms and 10 control farms recruited in each site – Given Novasil as a feed additive
  • 36.
    Follow up • Regularfollow up and endline survey of farmers • Preliminary results: • High dosing of binder reduces aflatoxin • Farmers perceive improved production • Compliance? • Concerns with adulteration
  • 37.
    Farmer Consumer 4. Inthe milk? Aflatoxin flow Human exposure AB1 AB1 AB1-> AM1 AM1 Corn/feed produced at farm Corn/feed purchased Milk produced at farm AB1 AM1
  • 38.
    4. In themilk • Biological control?? Research still ongoing Pasteurization not working
  • 39.
    Farmer Consumer 5. Stoppingconsumption of contaminated milk Aflatoxin flow Human exposure AB1 AB1 AB1-> AM1 AM1 Corn/feed produced at farm Corn/feed purchased Milk produced at farm AB1 AM1
  • 40.
    5. Stopping consumption •Legislation • Awareness and market incentives Implementation What do you do with illegal milk? Costs? Poor consumers?
  • 41.
  • 42.
    Take home messages •Livestock is affected by aflatoxins, and so are animal- sourced food • Livestock feed sector + binders can suck contaminated grain out of human food chain • Potential for regulation to cause harm (burden on agricultural sector, concentrating contaminated among poorest) • Need to research what works in each country
  • 43.
    Conclusions There is nosilver bullet to eradicate aflatoxins Animals may be both part of the problem and part of the solution
  • 44.
    The Kenya workis financed by the Ministry of Foreign Affairs, Finland in partnership with the International Food Policy Research Institute (IFPRI), Luke Finland and the Biosciences in eastern and central Africa–International Livestock Research Institute (BecA-ILRI) hub It contributes to the CGIAR Research Program on Agriculture for Nutrition and Health Acknowledgements
  • 45.
    The presentation hasa Creative Commons licence. You are free to re-use or distribute this work, provided credit is given to ILRI. better lives through livestock ilri.org