Toxic Principle MoA/CS

Question 1

Insoluble calcium oxalate

Answer 1

Penetration via needle shaped Ca oxalate crystals

Irritation of lips, mouth, throat, V+

Question 2

Soluble oxalate

Answer 2

Hypocalcemia—precipitation in tissues —> kidney damage

Methemogolobinemia

Question 3

Isocupressic acid

Answer 3

Vasoconstriction —> dec uterine blood flow —> fetal cortisol release —> abortion in cattle

Question 4

Quinone

Answer 4

Primary photosensitization

Erythema and pruritus, edema, skin necrosis (secondary bacterial infection)

Question 5

Tannic acid

Answer 5

Tissue damage
Cattle—constipation, brown urine, atony, anorexia, depression
Monogastric—mainly GI

Question 6

Colchicine

Answer 6

Anitimitotic

Involves many organs

Question 7

Diterpene alkaloids

Answer 7

Competitive blockade of nicotinic receptors (curare)

Sudden death, mm weakness, stiff, bloat, recumbency, collapse

Tx—physostigmine

Question 8

Indo alkaloids

Answer 8

Dec glycoproteins, peripheral neuro degeneration

Neuro signs, abnormal hoof + hair

Question 9

Lycorine

Answer 9

Emetic—V+, D+, mm tremor/seizure. Hypotension.

BULB MOST TOXIC

Question 10

Muscarine

Answer 10

CNS stimulant

Tx—atropine + symptomatic tx/decontamination

Question 11

Piperidine alkaloids

Answer 11

Nicotinic effects. Stimulation —> blockade

Ataxia, incoordination

TERATOGENIC

Question 12

Solanine alkaloid

Answer 12

Similar to atropine

GI, CNS, resp, <3

ONLY toxic when green + immature

Question 13

Tropane alkaloids

Answer 13

GI, CNS (convulsive seizures), mydriasis, tachycardia

ALL PARTS TOXIC

Tx—physostigmine

Question 14

Xanthine alkaloids

Answer 14

Block adenosine receptors, inhibit phosphodiesterase

Hypersalivation, V+, D+, colic, CNS stim (convulsive seizures), mm trem, tachycardia, hypotension, U+

Question 15

Anthraquinone

Answer 15

Similar to monensin

Purgative

Skeletal and cardiac mm degeneration —> myoglobinuria —> kidney damage

HORSES CAN DIE FROM LIVER FAILURE

Question 16

Calcinogenic glycoside

Answer 16

Vitamin D analog—inc calcium

Lameness

Same MoA as cholecalciferol

Question 17

Carboxy-atractyloside

Answer 17

HEPATOTOXIC

Hypersalivation, kidney damage, hypoglycemia

Question 18

Cardiac glycoside

Answer 18

Inhibit Na/K ATPase

Tx—Digoxin

Question 19

Coumarine glycoside

Answer 19

Inhibit Vitamin K epoxide reductase —> dec II, VII, IX, X

Hemorrhage

Dicoumarin in spoiled plants

Tx—vit K1/whole blood

Question 20

Cyanogenic

Answer 20

Acute—inhibit cell respiration. Mucous membrane irritation

Chronic—neuronal damage and anti-thyroid

Question 21

Cycasin

Answer 21

BMAA —> neurotoxic AA —> axonal degeneration in CNS

GI + liver dz syndrome or ataxia + CNS syndrome

TERATOGENIC + MUTAGENIC

Question 22

Nitropropanol glycoside

Answer 22

Inhibits enzymes in krebs cycle + cell phosphorylation

Cattle + sheep—cracker heels/roaring dz
Horses + rodents—neuro

Question 23

Phytoestrogens

Answer 23

Bind to estrogen receptors —> infertility in M + F

Infertility in F, dec libido + feminization in M

Question 24

Protoanemonin

Answer 24

Volatile oil released by hydrolysis of the glycoside

Severe irritation of GI mucosa and dermatitis

Question 25

Ptiquiloside

Answer 25

Death of precursor cells in BM, aplastic anemia, enzootic hematuria

Thiamine B1 deficiency ONLY in non-ruminant
Tx—thiamine/B1 IV

Question 26

Steroidal saponins

Answer 26

Photosensitization and liver damage (hepatogenic)

Can’t eliminate phylloerythrin

Question 27

Gossypol

Answer 27

Cardio toxic. Chronic. Monogastrics more sensitive

Cardio toxic + male fertility

Heat decreases toxicity

Question 28

Copper

Answer 28

Liver damage, hemolysis, methemoglobinemia

Question 29

Selenium

Answer 29

Acute—GI irritation + respiratory signs

Chronic—hoof + hair abnormalities

Question 30

Nitrate

Answer 30

Acute—fetal methemoglobinemia —> death —> abortion

Chronic—decrease progesterone during pregnancy —> abortion

Question 31

Resins/resinoids

Answer 31

Irritation of nervous or muscle tissue