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Flashcards in mycotoxins in small animals Deck (21):
1

which mycotoxins causes activation of nociceptors

  • t2 
  • very painful
  • eg stachybotrys

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2

which toxin casuses vomiting most in pigs

  • DON
  • The most prevalent mycotoxin in the Northern hemisphere
  • Vomiting (> 2000 ppb)
    • Feed refusal (Adaptation !) (>1200 ppb)
  • GI-dysfunction: Inflammation(< 800 ppb)
    • Decreased utilization of nutrients
    • Deregulation of the immune system

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3

THIS TOXIN CAUSES Impairment of innate immunity

Deoxynivalenol

4

EFFECTS OF Deoxynivalenol( DON) ON  Gut associated local immune response:

•Activation of MAPK
•Upregulation of IgA expression
•Upregulation of transcription factors (NFkB)
•Induction of pro-inflammatory cytokines
•Induction of COX-2
•Decrease of TEER (ABC transporters?)
•Loss of barrier function
•Impairment of Na+-glucose co-transport

  • N.B IT CAUSES Increased Susceptibility to viral and bacterial infections
    Vaccination failures

5

EFFECTS OF EXPOSERE OF DON ON PLANTS

  • DON – is toxic also for plants
  • A detoxicification mechanisme of plants is glycosinolation
  • Up to 60% of DON is glycosinolated in wheat .........................and not measured with common modern methods

6

WHICH TOXIN IS MOSTLY FOUND IN CORN THAN GRAIN

  • Zearalenone: ZEA, ZEN, F-2 toxin

7

WHICH TOXIN HAS HIGH BINDING AFFINITY FOR ESTROGEN RECEPTOS

Zearalenone: ZEA, ZEN, F-2 toxin

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8

the most prominant toxins in feed materials

Fusarium

9

NEGATIVE EFFECTS OF FUSARIUM 

Significant economic losses in farm animals (pigs, poultry) Clinical relevant featurse of trichothecenes are: Impairment of intestinal health (poor nutrient utilization)
Impairment of the immune system:
Increasing prevalence of viral diseases
Increasing incidence of bacterial infections
 (increased use of antibiotics – undesirable!)
Vaccination failures!
Zearalenone: economic losses due to impaired reproduction

10

MICRO ORGANISMS THAT INVADE SILAGE

Silage is invaded
by micro-aerobic
acid tolerant
moulds and yeasts

11

Compounds that protect the individual by inhibiting absorption from the gastro-intestinal tract or by inducing excretion pathways

CHEMOPROTECTORS

reduction of the internal dose Test protocol: Kinetic studies in target animals

12

Compounds that successfully prevent /mitigate adverse effects of mycotoxins

CHEMOPREVENTION

 interference with mechanisms of toxicity Test protocol: Measurement of biological (dynamic) effects (biomarkers of effect).

13

THIS ANTITOXIN Sequester & degrade certain mycotoxins

Probiotics & Bacterial enzymes

14

AFB1 epoxide-formation is inhibited by:

Green thea polyphenols Vegetables: psoralens, apigenin, quercitin naringenin, caffeic acid

15

list the chemicals that prevent absoption of mycotoxins

Bentonites
Sepolites
Smectides
-Montmorillonite
-Nontrionite

  • Mineral clay products: Ca-Na-Al-phyllosilicates

Able to bind polar mycotoxins: AFB1
In vitro binding
“Isotherms”
Bentonites
Sepolites
Smectides
-Montmorillonite
-Nontrionite
Commonly applied as feed additive to reduce the internal dose

16

what is the effect of t2 toxin in dogs

bleeding

17

what is the effect of t2 in cats

cardiovascular toxicity

18

practicioner's ddx of t2 

Idiosyncratic potentiated sulfonamide toxicity (pancytopenia, hemolytic anaemia)

19

ddx of DON BY PRACTISIONERS

  • age-related hypertension in cats,
  • urinary tract infections in dogs

20

THIS TOXIN ACTS AS Acts as agonist/antagonist on estrogen-receptors IN SM

  • Zearalenone (ZEA)
    • Impairs oocyte maturation
      in vitro
    • Stimulates ER-dependent
      cell proliferation

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