Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Toxicology > Range Plants (Western Canada) > Flashcards

Range Plants (Western Canada) Flashcards

1
Q

What is the most poisonous plant in western canada?

A

western water hemlock

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where is water hemlock and whats the toxic principle? what part?

A

obligate aquatic plant (marsh)
cicutoxin (long chain unsaturated diol)

young leaves, esp roots and tubers
yellow liquid ("carrot like odor")
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the MOA of water hemlock? (cicutoxin)?

A

uncertain

- directly acting neurotoxin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are the conditions of poisoning of water hemlock?

A

mistaken for wild carrot/parsnip
early spring
cattle most at risk but all species
toxin active when dry (hay)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the clinical signs of water hemlock?

A 
rapid onset (10-15mins)
violent
found dead
salivation, apprehension, muscle twitching, jaw clamping/teeth grinding
CNS stim
- spasmodic jerking, running fits
- horse will "back up weird"
clonic/tonic seizures --> coma
resp paralysis within 45-90min
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the Dx of water hemlock?

A 
found dead with struggle
history
clin path and histopathology
rumen contents
mouse bioassay of root extract
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the treatment of water hemlock?

A 
impractical in field but anesthetic dose of barbituates (control seizures) Diazapam not enough
avoid exposure (grazing management
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Where is yellow star thistle found and whats the toxic principle? what parts of the plant?

A 
aggressive weed (dry conditions)
California and interior BC
unidentified (in all parts)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the MOA of yellow star?

A

may be dopaminergic neurotoxin

  • acts to destory the dopaminergic nigrostriatal pathway (cerebral cortical pathway) involving CN 5, 7, 9
  • loss of neural connections
  • ischemic necrosis of substantia nigra and globus pallidus in brain
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the toxicity and conditions of yellow star?

A 
signs after continuous grazing for 30d
- consumption of BW over weeks/month
ONLY EQUIDS
- usually forced but can aquire it
- toxic when dry (hay)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are clinical signs of yellow star?

A

“equine parkinsons”
“chewing disease”

sudden onset after prolonged exposure
reflect necrosis of nuclei in brain
- hypertonicity of facial muscles, lower lip hand, paralysis of tongue (not flaccid) , yawning, head tossing, walk with head down
- chewing movements but cant chew food
- feed drops out
- cant drink (lip muscles)
emaciation, starvation, death
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the Dx for yellow star?

A

clinical signs, history, pathology

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is the Tx for yellow star?

A 
S&Scare
avoid exposure (grazing managment)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where is St Johnswort found? whats the toxic principle? significant feature?

A

roadside/pastures
dry gravel soils

hypericin (fluorescent photodynamic pigment)
in pigmented granules in leaves and flowers
“looks like holes”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Which plant acts in the same way as St Johnswort?

A

buckweat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the MOA of St johnswort (hypericin)?

A 
primary photosensitization (goes to capillaries in skin)
lightly pigmented skin (UVA exposure + oxygen = reaction)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the toxicity/conditions of St Johnswort?

A

low levels are toxic (high in young plants, mature foliage, new growth palatable)
- decreases with drying (still toxic)
many species at risk (unpigmented skin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the clinical signs of St Johnswort?

A

appear within 24h
erythema of non-pigmented skin –> edema –> vesicles –> necrosis
tachycardia, tachypnea, pyrexia, salivation, diarrhea
erythema of conjuctival and buccal MM (blindness, feed refusal)
Shock, hypotension, convulsions, death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the Dx of St Johnwort?

A

clinical signs
history
rule out liver problems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the Tx or St Johnswort?

A

remove, GI decontam, terminate UV exposure
treat skin leasions like burns (antibiotics
antihistamines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is secondary photosensitization and what plants cause it?

A

coal oil brush, lupin, flix weed, rape

agent is based on metablism of chlorophyl

  • converted to polyurethrine in the liver
  • liver damage can build up toxin
  • common in cattle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the toxic principe in Fiddleneck/tansy ragwort? where is it found? what part of plant?

A

pyrrolizidine alkaloids
in foliage and seeds

invaders in pasture (grain/hay fields)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the MOA of Fiddleneck/tansy ragwort?

A

toxin enters portal circ –> metabolized by P1 enzymes to pyrrole derivatives which bind cellular macromolecules DNA adducts –> impaired cell division –> hepatocytomegaly cell death –> hepatic necrosis, bile duct proliferation –> decreased liver function/failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the toxicity and conditions of fiddleneck/tansy ragwort?

A

acute toxicity, chronic more common

cattle and horses
contam of grain, hay or silage
overgrazing risk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
what are the clinical signs of fiddleneck/tansy ragwort?
hepatic insufficiency suddenly horses: cachexia +/- icterus, sleepy staggers "hepatic coma", delirium death Cattle: nervousness, mania, colic, diarrhea, tenesmus, rectal prolapse, hepatogenous photosensitization, death high doses --> hepatic necrosis and acute death
26
what is the Dx and Tx for fiddleneck/tansy ragwort?
clinical signs Hx alkaloid screen pathology S&S care prevent
27
What is the toxic principle of horsetail? where can you find it?
moist meadows, flood plains thiaminase in non-rum unknown in rum
28
What is the MOA of horsetail?
thiaminase splits thiamin into pyrimidine and thiazole rings | - inactivating the vitamin
29
What is the toxicity and conditions of horse tail?
``` significant exposure required young horses most at risk ruminants less sensitive pigs also toxic when dry (hay contam) ```
30
What are the clinical signs of horsetail?
progressive weight loss, ataxia, staggering, general peresis progressive rigidity, dyspnea, weak pulse, tremors --> convulsions recumbancy --> coma --> death
31
what is the Dx for horsetail?
clinical signs response from treatment Hx clin path and histopath
32
what is the Tx for horsetail?
remove from source | thiamine hydrochloride treatment
33
What is the toxic principle in bracken fern? where is it found?
eastern manitoba, riding mountains and BC upland or old burns ``` Thiaminase in non rum in rum: - aplastic anaemia factor - enzootic hematuria factor - cyanogenic glycoside ```
34
what is the MOA of bracken fern?
thiaminase induced thiamine deficiency in non-rum non-thiaminase in cattle - toxin acts on bone marrow --> aplastic anemia - converted to carcinogen in bladder
35
What is the toxicity/conditions of bracken fern?
prolonged exposure (hay contam) horses or rum many species grazing risk in late summer (thiaminase levels peak)
36
What are the clinical signs of bracken fern?
monogastrics - progressive cahcexia and neuro signs (ataxia, stance, knuckling, tremors, recumbancy, convulsions, death) Ruminants: - aplastic anemia/acute hemorrhage syndrome - depression pyrexia, anorexia, emaciation, widespread hemorrhage - death 4-8d later - neoplastic syndrome/enzootic hematuria (latent months years) - bladder transitional cell carcinoma (bleed)
37
What is the Dx of bracken fern?
clinical signs history of prolonged exposure clin path histopath
38
What is the Tx of bracken fern?
remove source horses: thiamine hydrochloride treatment Cattle: S&S care
39
What is the toxic agent of lupine? Where is it found? defining feature?
teratogenic alkaloid anagyrine mountain slopes finger-like leaflets
40
what is the MOA of lupines?
nicotinic like alkaloids = CNS stim or depres teratogen anagyrine = arthrogryposis ("crooked calf") - sedates them in utero
41
What causes crooked calf disease?
lupine | teratogen anagyrine
42
What is the toxicity and conditions of lupines?
``` sheep - foliage prolonged exposure - seeds very toxic cows - little needed - teratogenic ``` sheep most often variation in season hay contam seed pods in fall
43
What are the clinical signs of lupines?
vary CNS depress - dyspnea, depression, coma, death from resp paralysis CNS stim - trembling, headpressing, teeth grinding, falling, convulsions, death crooked calf syndrome
44
what is the Dx for lupines?
clinical signs Hx pathology
45
What is the Tx for lupines?
decontam S&S care avoid cattle exposure during peak period (fall) grazing managment
46
What is the toxic principle of False Hellebore? where is it found?
rockymountains in wet meadows ``` steroidal alkaloids teratogenic alkaloids (cycloposine) ```
47
What is the MOA of False Hellebore?
MOA for acute uncertain teratogenic alkaloid - selective inhibtion of mitosis during cell division (facial or limb deformities
48
What is the toxicity/condition of False Hellebore?
toxic teratogenic dose much less sheep generally only species at risk - acute greatest risk in spring - when ewes graze mountain meadows
49
what are the clinical signs of False Hellebore?
acute syndrome - 2-3h - salivation, vomiting, diarrhea, weakness, ataxia, bradycardia, cyanosis, recumbancy, convulsions, paralysis - death in 6-18h Teratogenic - cyclopean malformations + fetal pituitary gland --> prolonged gestation (24-30d) - cleft palate (25-36d) - hypoplasia of metacarpals and metatarsals - tracheal stenosis
50
What is the Dx of False Hellebore?
clinical signs Hx path congenital defects
51
What is the Tx of False Hellebore?
GI decontam S&S care avoid exposure during spring
52
What is the toxic principle in ponderosa/western yellow pine? where are they found? what parts?
labdane resic acids isocupressic acid acetly-ICA succinyl-ICA - ICA = abortifacient rockies and foothills needles, new growth tips, bark
53
What is the MOA of ponderosa?
uncertain
54
What is the toxicity and conditions of ponderosa?
for 3 days in last trimester = abortion cattle may abort after single feeding cattle, bison, llamas sensitive during last trimester horses and other rum resistant risk in late winter/spring = forces cattle to eat dried or green
55
what are the clinical signs of ponderosa?
abortion 48h to 2w after exposure - depression, edema of vulva and udder, bloody discharge, weak uterine contractions, incomplete cervical dilation - aborted fetus may be autolyzed - retained placenta and metritis common - live calves born weak will die
56
What is the Dx of ponderosa?
clin signs (late term abortion) history pathology
57
What is the Tx of ponderosa?
S&S care with cows | avoid exposure during latespring/winter
58
What is the toxic principle of group 2 astragalus (loco)? where is it found? what part?
dry plains/hill country with alkaline soils may be indolizidine alkaloid (swainsonine) foliage
59
What is the MOA of loco?
swainsonine inhbits saccaride metabolism - accumulation of oligosaccharides in cells of brain and other organs - lysosomal storage disease (build up)
60
What is the toxicity and conditions of loco?
varies typically prolonged exposure (but not high doses) sheep it takes a lot horses most sensitive can get habituated, young animals (passed in milk, affects maturing neurons)
61
What are the clinical signs of loco?
depression, anorexia, weightloss, trembling, ataxia, excitability loss of sense of direction and herding instinct (circling, wandering off, attitude/behavioural changes) abortions and congenital defects
62
What is the Dx for loco?
``` clinical signs hx clin path - leukopenia/lymphopenia histopath ```
63
What is the treatment for loco?
remove from source mild cases resolve in 1-2w chronic never recover
64
What is the toxic principle of Death Camas? where is it found? what parts?
steroidal alkaloids (all parts) hillsides to 8000ft AK and AB
65
What is the MOA of Death Camas?
inducing arteriole dilation = hypotension constricts venules slowing of HR
66
What is the toxicity/conditions of Death Camas?
interspecies variation seeds more toxic bulb highly toxic confused with wild onion early spring risk sheep especially susceptible toxic when dry
67
What are the clinical signs of Death Camas?
often found dead signs within 1-2h salivation, colic, vomiting, tachypnea, trembling, ataxia, pulse weak, rapid, irregular hypothermia weakness > depression > recumbancy > coma agonal struggling/jaw clamping
68
What is the Dx of Death Camas?
clin signs (signs of struggle, foaming) Hx alkaloid screen of rumen path
69
What is the Tx of Death Camas?
impractical in field S&S avoid (grazing managment)
70
What is the toxic principle in Larkspur? where is it found? what parts?
multiple polycyclic diterpene alkaloids tall larkspur - foothills, rockies and interior BC low larkspur - S AB and BC all parts
71
What is the MOA of Larkspur?
curare-like neuromuscular blocking agent | post synaptic nicotonic cholinergic receptors at NMJ
72
What is the toxicity/conditions of Larkspur?
varies with species/environ cattle low dose (tall more common) sheep and horses less sensitive risk in hay
73
What are the clinical signs of Larkspur?
rapid course often dead nervous signs - excitability, nervousness, disorientation, stiffness, muscle tremors, loss of motor control, convulsions, fall downhill resp depression, bradycardia, hypotension, death from resp paralysis or bloat (within 3-4h) milder cases = GI signs and bloat
74
What is the Dx of Larkspur?
clin signs Hx alkaloid screen path
75
What is the Tx of Larkspur?
impractical in field S&S avoid exposure

Toxicology (27 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions