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Flashcards in Exam 1--LA Toxins Deck (110)
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1

Blister beetles are associated with which type of feed stuff & what toxin do they release?

Alfalfa Hay
Cantharidin

2

In addition to GI effects in horses, what other system might appear compromised with blister beetle toxicity and why?

Renal--cantharidin is excreted in urine

*dysuria, nephrosis, cystitis

3

Buttercups:
1) which system do they affect
2) which spp?

1) GI
2) livestock

4

Pokeweed:
1) system affected?
2) toxic principle?

1) GI
2) Saponin

5

Quercus can cause toxic effects in which systems?

What are 2 characteristic clinical signs?

GI
Renal

Bloody or dark diarrhea with acute renal failure

6

Which 2 plants can cause both GI and neuro signs?

Chinaberry

Nightshades (Jimson weed is neuro)

7

Toxic principle for chinaberry?

Tetranortriterpenoids

*Tetra-nor-tri-terpenoids

8

What are the 3 toxic principles found in nightshades & general effect of each?

1) Solanine (GI & neuro toxic)

2) Tropane alkaloids (anticholinergic)

3) Nicotine (cholinergic)

9

MOA of toxalbumins?
Which part of plant is typically toxic?
Which spp. most affected?

1) inhibition of protein synthesis (ribosomal inhibiton)

2) SEEDS (intact seed= not absorbed)

3) HORSES

10

Violent purging (bloody diarrhea with straining) along with other GI signs would be suggestive of?

Toxalbumin toxicity (i.e. Castor beans)

11

Toxic principle in castor beans? It's MOA?

Ricin--inhibits 60s ribosomal subunit

12

Toxic principle of Rhododendron spp. and its MOA?

Grayanotoxin

Increases membrane permeability to Na

13

In addition to vomiting in goats (GI), which other system can rhododendrons affect?

Cardio

*can lead to fatal bradycardia

14

A unique treatment option for animals that have eaten persimmons?

Carbonated cola

15

Describe where nitrates are located in the plant and what can cause it to accumulate?

Bottom 1/3 of stalk (grains and leaves are less toxic)

accumulates in stressful conditions--plants stops growing and metabolizing it

16

Which spp. is most susceptible to nitrates and why?

Describe nitrate MOA

Ruminants (convert it to nitrite in rumen)

*Nitritie oxidizes hemoglobin to methemoglobin, which cannot bind O2

17

T/F: finding blue/brown MM in a cow can confirm nitrate toxicity

FALSE

**brown MM only SUGGESTIVE

18

Nitrates:
1) what sample is taken to measure for nitrate/nitrite levels?

Plasma

19

2 treatment options for nitrate/nitrite

Methylene blue (converts MetHgb-->Hgb)

Rumen lavage with cold water (slows microbial activity=less nitrite produced)

20

Name 2 plants that can accumulate nitrates?

Pigweed
Johnson grass

21

Wild black cherry & choke cherry impact which system?
Toxic principle?

Hematologic;

Prussic acid (cyanide)

22

Bright red MM and sudden death are common clinical manifestations of which toxin?

Cyanogenic glycosides (cyanide)

23

What 2 drugs are used in combination when treating cyanide toxicity?

Sodium nitrate followed by sodium thiosulfate

24

Copper toxicity:
1) most susceptible spp.
2) most common type of exposure

1) Sheep!

2) chronic dietary exposure

25

Because copper causes _____ hemolysis, an expected UA finding would be _______

intravascular; hemoglobinuria

26

Since red maples causes _______ damage to RBCs, you would expect _____ _____ anemia

Oxidative;

Heinz body

27

Bracken Fern:
1) Which spp. are susceptible---which is most?
2) toxic principle
3) System(s) affected

1) CATTLE* (also sheep & horses)

2) Ptaquiloside

3) Hematologic & Renal

28

What are the 3 clinical syndromes associated with Bracken Fern?
Which is most common?

1) Hemorrhagic disease
2) Enzootic hematuria (MOST COMMON)
3) Neurologic disease

29

In which spp. does Bracken fern typically cause neuro disease? Why?

Horses--can't synthesize thiamine like ruminants can

*Thiaminases

30

Sweet clover toxicity MOA?
*include toxic principle in description

Dicourmarol inhibits vitamin K epoxide reductase

Decreased synthesis/activity of vit K-dependent factors (2,7,9,10)

31

Describe the pathogenesis of ABPEE?

Rapidly changed to lush forages containing L-tryptophan, which is converted in rumen to 3-methylidole (3-MI)

3-MI absorbed, metabolized by clara cells in lungs-->damage-->difficult to transport O2 across thickened endothelial cells

32

Perilla Mint:
1) system affected
2) toxic principle

1) Respiratory
2) perilla ketone

33

What spp. of fungus infects sweet potatoes?

Fusarium solani

34

The mold on moldy sweet potatoes causes production of what toxic substance?

4-ipomeanol

35

Name 3 noxious gases that can affect cattle?

Maure gase
Nitrogen Dioxide (silos)
Zinc oxide (welding)

36

What two plants are included with Senna spp.? What system do they affect?

Coffeeweed
Sicklepod

Musculoskeletal

37

Which enzymes, associated with muscle, would you expect to be elevated with Senna spp. toxicity? (3)

1) CK
2) AST
3) cardiac troponin

38

Bedding containing the shavings from which plant can be toxic for HORSES?

Black walnut (Juglans nigra)

**if >20% black walnut shavings

39

Alkali disease is an excess of?

Selenium

40

MOA of selenium toxicity?

2 Most common clinical signs?

Replaces sulfur in amino acids (glutathione depletion & free radical formation)

Hoof deformities
Loss of tail/mane hairs

41

Indicator plants can be used for detection of?

High Se levels in soil

42

Which 2 systems can fescue impact?

Musculoskeletal
Repro

43

Fescue:
1) toxic principle?
2) most clinical signs occur due to what effect of fescue?

1) Ergot alkaloids

2) vasoconstriction (dry gangrene or extremities & summer slump)

44

Oleander & Rhododendrons are what type of cardiac toxins?

Yew?

Cardiac glycosides

Cardiac alkaloid

45

Which spp. is most susceptible to ionophore toxicity?

Horses

46

Name the muscle preference for ionophores in the following species:
1) horses
2) cattle
3) sheep/swine

1) cardiac >> skeletal

2) cardiac = skeletal

3) skeletal > cardiac

47

In which cotton products can the toxin (gossypol) be found?

whole cottonseed
cottonseed meal

48

Which two systems can be impacted by gossypol?

Cardio (monogastrics)
Repro (male ruminants)

49

Myocardial damage
decreased milk production
olive-colored eggs
decreased spermatogenesis

All above signs can be related to?

Gossypol

50

Name 4 effects of the cardiac glycosides on the heart

1) Blocks Na/K ATPase
2) increased vagal tone
3) increased myocardial contraction
4) decreased coronary artery blood flow (vasoconstriction)

51

For which toxicity would atropine be indicated and why?

Oleander--to combat increased vagal tone

52

Toxic principle of Yew? MOA?

Taxines

block Na movement through membrane, depressing cardiac conduction

53

The repro effects of fescue are primarily seen in which spp.?

The ergot alkaloids decrease secretion of?

Horses

Prolactin

54

When should the mare not graze fescue to avoid clinical signs?

First and last 30-45 days of gestation

55

An estrogenic mycotoxin that infects corn?
What spp. of fungus produces it?

Zearalenone

Fusarium spp.

56

Which group of animals is most susceptible to Zearalenone? Prominent clinical sign?

Pre-pubertal gilts

Vulvar edema

57

Phytoestrogens interact with specific estrogen receptors and are called _____ _____ _______ _______

Selective estrogen receptor modulators (SERMs)

58

Toxic principle of locoweed?
(As it relates to repro disease)

Swainsonine

*interferes with glycoproteins

59

In addition to repro, which other system does locoweed PRIMARILY affect?

Neuro (locoism)

60

Which signaling pathway does Veratrum disrupt?

Sonic hedgehog

61

Cyclopia associated with Veratrum commonly occurs if ingested on day ___ of gestation

14

62

Which "syndrome" is associated with lupine intoxication?

Crooked calf syndrome (arthrogryposis of forelimbs--elbows)

63

Lupine: where in the plant are toxins highest? Why is this bad?

Seed pods

bad because seed pods are palatable!

64

In addition to teratogenic repro effects, Lupine can also affect which other system?

Neuro

*nicotinic effects

65

When differentiating poison hemlock from water hemlock, what feature can you use?

Where the veins terminate

Water hemlock--veins terminate BETWEEN teeth

Poison hemlock--veins terminate at ends of teeth

66

Ponderosa pine has what effect on which species?

Abortion in cattle

67

Describe how ponderosa pine causes abortion

Powerful vasoconstrictor of uterine/caruncular vascular bed--> reduced blood--> decreased O2 & nutrient delivery to fetus

68

Why might you see abortions with nitrate toxicity?

methemoglobin formation leads to asphyxiation of fetus

69

Describe the pathogenesis of food related ammonia poisoning... include how the presence of liver disease is a risk factor

NPN converted to ammonia in rumen via ureases

not enough ketoacids present to combine with all ammonia-->excess ammonia absorbed into circulation

Usually can be detoxified by the liver (liver dz); if not it can travel to brain and impair astrocyte K buffering

70

What two factors make urease more efficient? How does this relate to our treatment of food related ammonia poisoning?

1) high rumen pH
2) elevated body temperature

This means that treatment involves lowering pH (acetic acid) and lowering rumen temperature (cold water)

71

Which 2 plants are included in Centauria spp.?

Yellow starthistle

Russian knapweed

72

Centauria:
1) system affected
2) main spp. affected
3) general MOA

1) neuro
2) horses
3) degeneration of dopaminergic neurons (equine parkinsonism)

73

Name 2 major neurotoxic principles associated with Locoweed

1) swainsonine

2) Misertoxin

74

Species most susceptible to locoweed?

Horses

75

Which toxin of Locoweed:
1) is associated with behavioral changes (i.e. hyper-reactive to handling)
2) is associated with HL ataxia (cracker heels) & posterior paralysis

1) swainsonine

2) miserotoxin

76

What can be used for aversion therapy against locoweed?

Single oral dose of lithium chloride

77

Which plants are included in Aesculus spp.?

Buckeye (pointy leaf)
Horse chestnut (round leaf)

78

Toxic principle of Aesculus spp?

Triterpenoid saponins

79

Toxin associated with bovine bonker's syndrome?
Source?

4-methyl-imidazole

Ammoniated feeds

80

Name 4 grasses that can be associated with grassland staggers?

Perennial rye grass
Dallis grass
Bermuda grass
Annual rye grass

81

toxic principle in grassland staggers? MOA?

Tremorgens

impair inhibitory pathways in nervous system (GABA & lysine)

82

Toxic principle of water hemlock? MOA?

Cicutoxin

GABA antagonist--prevents influx of Cl-->CNS stimulation and seizures

83

Toxic principle of white snake root? MOA?

Tremetol--inhibits TCA cycle

84

A horse that's BAR, shows ataxia of only the hindlimbs, and also dribbles urine could be suspected of grazing on?

Sorghum

85

Larkspur toxic principle & MOA?

Polycyclic diterpene alkaloids

neuromuscular blocking agent at cholinergic and nicotinic receptors

86

Which toxic principle of Jimson weed (nightshade) causes neuro signs?

Tropane alkaloids

*non-depolarizing muscarinic blockers

87

Briefly describe Physostigmine's MOA as it relates to treatment of toxicities that block cholinergic receptors

competitively inhibits cholinesterase-->ACh builds in synapse to compete with toxic compounds

88

Toxic principle of poison hemlock? Which 2 systems does it affect?

Piperidine alkaloids

Repro & neuro

89

Lupine MOA?

mimics ACh at sympathetic and parasympathetic ganglia

90

Photosensitization secondary to liver dz is associated with which compound in the skin?

Phylloerythrin

91

Cocklebur (Xanthium):
1) system affected
2) spp. affected

1) hepatic

2) swine >> cattle, sheep > horses

92

In addition to clinical signs, what clinc path findings would correlate with Xanthium toxicity?

severe hypoglycemia
elevated liver enzymes
decreased electrolytes (normal kidneys)

93

Which 2 plant spp. are associated with PA toxicity?

Ragwort-groundsel
Crotalaria

94

Blue-green algae is associated with stagnant ponds high in ____

phosphorus

95

Blue-green algae MOA?

inhibits cytoskeleton intermediate filaments-->intrahepatic hemorrhage and necrosis

96

Sneezeweed:
1) system affected
2) susceptible spp.

1) Hepatic
2) sheep, goats > cattle, horses

97

Bitterweed
1) system affected
2) susceptible spp.

1) hepatic

2) sheep, goats >cattle, horses

98

Kochia
1) system
2) susceptible spp.

1) hepatic
2) ruminants

99

Which hepatotoxic plant is associated with birefringent crystals in bile ducts?

Panic grasses

100

Which hepatotoxin primarily affects HORSES (find it palatable)

Alsike clover

101

Vetch:
1) system affected
2) susceptible spp.

1) dermal
2) cattle

102

Toxic principle of St. Johnswort?

Hypericin (fluorescent pigment)

103

Which dermal toxin is associated with hyper-reactivity to cold water?

St. Johns wort (Hypericum)

104

Cestrum diurnum:
1) system affected
2) susceptible spp.

1) Urinary
2) cattle & horses

105

Cestrum diurnum mimics what other toxicosis?

Vitamin D intoxication

*acts like free vitamin D

106

Name 4 plants that contain soluble oxalates

1) beets
2) Curly dock
3) Lamb's Quarter
4) Rhubarb

107

Soluble oxalate MOA?

combine with serum Ca to form insoluble Ca-oxalates that block renal tubules

108

Clinical pathologic changes expected with soluble oxalate toxicity?

Hypocalcemia
Hyperkalemia
Elevated BUN

109

Toxic principle of Halogeton?

Na & K oxalates

110

Though primarily hematologic, pigweed may also affect?

Renal (contains oxalates)