Aflatoxin Contamination: Occurrence and Management

1
Aflatoxin Contamination Occurrence and Management
Thomas Isakeit Cooperative Extension, The
Texas AM University System
2
AFLATOXINS WHAT ARE THEY?
- TOXIC CHEMICALS PRODUCED BY FUNGI (Aspergillus
flavus and A. parasiticus) GROWING IN CROPS -
CAUSE DISEASE IN ANIMALS AND HUMANS
(MYCOTOXICOSIS) - MAY BE PRODUCED IN THE FIELD OR
AFTER HARVEST - AFFECT MANY TYPES OF CROPS
3
TYPES OF AFLATOXINS
STRUCTURE OF B1, THE MOST POTENT AFLATOXIN,
SPECIFICALLY REGULATED IN SOME COUNTRIES
ALSO

• B2, G1 AND G2
• M1 AND M2 IN MILK SPECIFICALLY REGULATED

4
AFLATOXIN TOXICITY - HUMANS

• HEPATIC AND GASTROINTESTINAL INJURY
• IMMUNOSUPPRESSIVE
• TERATOGENIC
• ONCOGENIC
• SEVERE LIVER INJURY, SOMETIMES FATAL (2-6 MG/DAY
  FOR A MONTH)

5
AFLATOXIN TOXICITY - ANIMALS
LUNG LESIONS IN A PIG POISONED BY AFLATOXIN

• VARIOUS SYMPTOMS FROM REDUCED GAIN TO DEATH
• VARYING SENSITIVITY AMONG SPECIES

6
AFLATOXIN POISONING FROM CORN RECENT CASES

• TEXAS, 1998 25 DOGS DIED 100-200 PPB,
  FULL DIET FOR 90 DAYS
• KENYA, 2004 125 PEOPLE DIED, 192 POISONED
  DAMP STORAGE OF CORN, UP
  TO 8,000 PPB

7
LOSS FROM AFLATOXIN IN TEXAS CORN IN 1998

• YIELD LOSS FROM DROUGHT
• PRICE DROP (2.20/BU vs. 2.80)
• 407 MILLION VALUE W/O TOXIN
• 18 31 CROP CONTAMINATION
• TOXIN VALUE 1.30 - 1.40 / BU

17 - 40 MILLION LOSS
8
HISTORY IN TEXAS
LOSING TURKEYS I CUT THEM OPEN AFTER THEY DIE
AND FIND A BIG LIGHT COLLORD LIVER THE GIZZARD
IS ENLARGED, ALSO THE GALL IS TWICE AS LARGE AS
SHOULD BE.
- LETTER TO FARM AND RANCH, MAY 19, 1917 FROM
VAN ZANDT COUNTY, TX
AFLATOXIN?
9
HISTORY IN TEXAS


J.J. Taubenhaus documents A. flavus as a pathogen
10
ASPERGILLUS EAR ROT
A. FLAVUS IS A WEAK PATHOGEN THAT DOES NOT ALWAYS
PRODUCE SYMPTOMS
11
CONSEQUENTLY, AFLATOXIN DETECTION REQUIRES A
CHEMICAL ANALYSIS
EXTRACTION
PURIFICATION
ANALYSIS
DETECTION IS DIFFICULT!
12
SAMPLING IS MORE DIFFICULT!
CONTAMINATION IS NOT UNIFORM
- WITHIN A REGION - WITHIN A FIELD - ON A
PLANT - WITHIN AN EAR - WITHIN A SEED
13
AFLATOXIN DISTRIBUTION IN TEXAS


2002 CORN ACREAGE
2003 CONTAMINATION
14


COMPILED BY OFFICE OF THE TEXAS STATE CHEMIST
15


COMPILED BY OFFICE OF THE TEXAS STATE CHEMIST
16
AFLATOXIN IN AN EAR OF CORN
CONCENTRATIONS ARE DIFFERENT FOR EACH KERNEL
17
WHERE AFLATOXIN OCCURS IN A CORN SEED (SHOWN IN
RED)
AS SHOWN BY THE RED COLOR MUTANT, AFLATOXIN IS
FOUND IN THE ALEURONE
18
A SMALL PROPORTION OF CORN IS HIGHLY
CONTAMINATED 1 KERNEL WITH 400,000 PPB WILL
MAKE A 10-LB SAMPLE MEASURE 26 PPB
19
WHERE DOES THE FUNGUS COME FROM?

• airborne infective spores
• survival in soil

Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
20
SCLEROTIA OF A. FLAVUS
DETAIL RED BAR IS APPROX. 1 MM
21
HOW THE FUNGUS ENTERS THE EAR

• SPORES FALLING INTO WOUNDS CAUSED BY INSECTS
  (E.G. CORN EARWORM AND SOUTHWESTERN CORN BORER),
  OR CARRIED ON THEM
• CAN GROW DOWN SILKS (NO WOUNDING NECESSARY),
  SHORTLY AFTER POLLINATION

Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
22
HOW THE FUNGUS ENTERS THE SEED


A WOUND IS USUALLY NEEDED
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
23
SILK CUT
STRESS-RELATED LOSS OF KERNEL INTEGRITY
24
PREDISPOSING FACTORS FOR CONTAMINATION

• DROUGHT
• HIGH TEMPERATURES AT FLOWERING
• INSECT INJURY
• STRESS ON PLANT INCREASE IN PATHOGEN
  REPRODUCTION

Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
25
FACTORS AFFECTING AFLATOXIN PRODUCTION

• ACTIVITY DOES NOT START UNTIL KERNEL MOISTURE
  lt32
• BEST RANGE IS 16-20 MOISTURE, 18 IS OPTIMAL
• OPTIMAL 77-86o F, BUT FUNGUS GROWS WELL AT 97o F

26
AFLATOXIN MANAGEMENT IN THE FIELD (PRE-HARVEST)


- host resistance - insect control - cultural
practices - biological treatment
USE OF SEVERAL APPROACHES
27
HOST RESISTANCE


- TO INSECT, CONVENTIONAL TRANSGENIC (Bt) NOT
ENOUGH - TO FUNGUS SOURCES IN LINES, NOT EASY TO
INTRODUCE INTO HYBRIDS - IMPROVED HOST TOLERANCE
TO STRESS
28
HUSK COVER IS A TRAIT ASSOCIATED WITH LESS
AFLATOXIN
29
HUSK COVER AND AFLATOXIN


A TREND TOWARDS MORE AFLATOXIN WITH AN OPEN HUSK
BETRAN ISAKEIT, 2004. AGRON. J. 96565
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
30
AFLATOXIN AND HYBRID MATURITY


BETRAN ISAKEIT, 2004. AGRON. J. 96565
MORE AFLATOXIN WITH EARLY-MATURING VARIETIES
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
31
AFLATOXIN AND MATURITY


A TREND TOWARDS LESS AFLATOXIN IN HYBRIDS WITH A
LONGER MATURITY
BETRAN ISAKEIT, 2004. AGRON. J. 96565
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
32
CORN BREEDING AND AFLATOXIN


EVALUATION FOR RESISTANCE REQUIRES MORE TIME AND
LABOR THAN OTHER TRAITS
33
PESTICIDE TREATMENTS


INSECTICIDES TARGETED TO - REDUCE PLANT STRESS
(E.G. PRESCRIBE FOR ROOT INSECTS) - REDUCE EAR
INJURY FUNGICIDES ARE NOT EFFECTIVE OR PRACTICAL
34
CULTURAL PRACTICES

• - PLANTING DATE
• - PLANT POPULATIONS
• - WEED PEST CONTROL
• IRRIGATION
• TILLAGE TO BREAK HARD PAN
• ADEQUATE FERTILITY

35
CULTURAL PRACTICES


WHATEVER YOU DO TO GET THE BEST CROP POSSIBLE
DOES NOT CONFLICT WITH MYCOTOXIN MANAGEMENT
36
BIOLOGICAL CONTROL

• AF36 LABELED FOR COTTON IN TX AND AZ
• AFLA-GUARD GA PEANUTS
• - APPLIED EARLY SEASON TO COVER FIELD
• - AREA-WIDE TREATMENT
• - CARRY OVER (PLACE/TIME)

37
HARVEST PRACTICES

• - SEGREGATE HARVEST OF GOOD AND BAD FIELDS
• CHANGE COMBINE SETTINGS TO REMOVE DAMAGED SEED
• EARLY HARVEST, FOLLOWED BY ARTIFICIAL DRYING
• - CLEANING SEED AFTER HARVEST (E.G. DENSITY
  SEPARATOR)

38
MYCOTOXINS IN INTACT AND DAMAGED/DISCOLORED
KERNELS


GOOD 35 PPB AFLATOXIN 1 PPM
FUMONISIN DAMAGED OR DISCOLORED 270 PPB
AFLATOXIN 9.3 PPM FUMONISIN
REPRESENTATIVE DAMAGED KERNELS
39
AFLATOXIN CONCENTRATION CAN INCREASE THE LONGER
CORN IS LEFT IN THE FIELD
40
AFLATOXIN POST-HARVEST MANAGEMENT

• PROPER STORAGE CONDITIONS TO MINIMIZE INCREASE
• BLENDING WITH CLEAN CORN SUBJECT TO FEDERAL
  AND STATE REGULATIONS CHECK FIRST!
• CHEMICAL NEUTRALIZATION IS SUBJECT TO FEDERAL
  AND STATE LAWS CHECK FIRST!

Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
41
STORAGE CONDITIONS

• OBJECTIVE IS TO KEEP THE FUNGUS WITHIN THE GRAIN
  DORMANT
• STORE CORN AT lt15 MOISTURE AND KEEP OUT
  MOISTURE
• PROPER OPERATION OF VENTILATION TO PREVENT
  MOISTURE CONDENSATION CAUSED BY UNEVEN
  TEMPERATURES IN BIN

Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
42
MOISTURE MIGRATION IN A BIN
TEMPERATURE DIFFERENCES WITHIN THE BIN LEAD TO
AIR MOVEMENT, WITH MOISTURE CONDENSATION AT THE
TOP OF THE BIN. PROPER VENTILATION WILL PREVENT
THIS.
DIAGRAM ROSS ET AL., 1974 U. KY. AEN-20
43
CHEMICAL TREATMENTS

• AMMONIATION SUBJECT TO STATE AND FEDERAL
  REGULATIONS
• OZONATION NOT COMMERCIALLY AVAILABLE
• ABSORBENT CLAYS ADDED TO FEED (E.G. NOVASIL)
  NOT YET APPROVED BBY REGULATORY AGENCIES

Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 3. Aflatoxin content of early, intemediate
and full season hybrids
Figure 4. Relationship between aflatoxin content
and maturity.
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
Figure 5. Husk cover of early, intemediate and
full season hybrids
Figure 6. Relationship between husk cover and
aflatoxin content..
44
ENTEROSORBENT CLAY ADDITIVE


AFLATOXIN PRESENT IN FEED
NOVASIL ADDED TO CONTAMINATED FEED
PHOTOS OFFICE OF THE TEXAS STATE CHEMIST
45
OZONATION OF CONTAMINATED CORN EFFECT ON GROWTH


PHOTO MCKENZIE ET AL. POULTRY SCI., 1998