Lecture 5

Question 1

What are examples of phenoxyacetic herbicides

Answer 1

2,4-D (scotts weed and feed)
2,4,5-T
Silvex

Question 2

How toxic are phenoxyacetic acid herbicides

Answer 2

Very low toxicity

Question 3

MOA of phenoxyacetic acid herbicides

Answer 3

Unknown

Question 4

What are GI effects of phenoxyacetic acid herbicides

Answer 4

Usually GI are the only signs seen in dogs

Vomiting, diarrhea (bloody), oral and GI ulcerations

Question 5

What are muscle effects of phenoxyacetic acid herbicides

Answer 5

Hesitation to move, rigid skeletal muscle, ataxia, weakness, seizures, myotonia with high doses, rumen atony

Question 6

What are other signs of phenoxyacetic acid herbicides

Answer 6

Renal tubular degeneration

Hepatic necrosis

Question 7

How to diagnose phenoxyacetic acid herbicides

Answer 7

Oral and GI ulcers
Enteritis and rumen stasis
Congestion of kidney/liver
Hyperemia of lymph nodes
Chemical analysis of serum and urine

Question 8

Treatment of phenoxyacetic acid herbicides

Answer 8

Emesis, lavage, bath
Activated charcoal
Ion trapping IF kidneys are normal

Question 9

What produces ergot alkaloids

Answer 9

Claviceps purpurea in small grains

Question 10

Ergot alkaloids MOA

Answer 10

Dopamine and serotonin agonists which produce hallucinations, decreased prolactin secretion, smooth muscle contraction from alpha 1 antagonist

Question 11

Clinical signs of erogtism in cattle

Answer 11

Reduced feed intake and weight gain, heat intolerance, retain winter coat “summer slump”

Gangrene of extremities
Fat necrosis
Poor repro performance

Question 12

Clinical signs of ergotism in other animals

Answer 12

Horses- abortions, weak foals, prolonged gestation

Pigs- infertility, early parturition, decreased milk production

Question 13

How to diagnose ergotism

Answer 13

See sclerotia in feed

Question 14

How to treat ergotism

Answer 14

Remove source

Metoclopromide and domperidone to increase prolactin and normalize gestation in mare

Question 15

What are ionophores

Answer 15

Compounds that form lipid soluble complexes with cations
Used as antibiotics
Ex: monensin, salinomycin

Question 16

Ionophores MOA

Answer 16

Increase intracellular Na and Ca leading to mitochondrial swelling and cell death

Question 17

What usually causes ionophore toxicosis? Who is most susceptible

Answer 17

Feed mixing errors

Horses are most sensitive, poultry are least sensitive

Question 18

Clinical signs of ionophore toxicosis for horses and cattle

Answer 18

12-72 hours after ingestion
Anorexia, colic, profuse sweating on flanks, uncoordinated and weak

Cattle are similar to horses but with diarrhea and resp difficulty

Question 19

Clinical signs of ionphore toxicosis of other animals

Answer 19

Unlikely
Poultry- down with legs and wings stretched out
Dogs- posterior paresis and paralysis
Cats- polyneuropathy

Question 20

Diagnosis of ionophores

Answer 20

Increased muscle enzymes, myoglobinuria, AST, CK, ALP, BUN, bilirubin
Decreased K and Ca
Chemical analysis of feed

Question 21

What should you differentiate ionophore toxicosis from

Answer 21

Other causes of colic, vitamin E or selenium deficiency, white snakeroot, blister beetle, gossypol, botulism

Question 22

Treatment for ionphore

Answer 22

No specific treatment

Supportive therapy and feed change

Question 23

Who does tetanus mostly affect

Answer 23

Cattle when spores get in puncture wounds

Question 24

Tetanus MOA

Answer 24

Blocks release of GABA and glycine

Question 25

Clincial signs of tetanus

Answer 25

``` Stiffness and reluctance to move Twitching and tremors of muscles Lockjaw Unsteady gait with stiff tail Bloat Collapse, spasm, death ```

Question 26

Treatment of tetanus

Answer 26

Antitoxin but only useful at very early stages Supportive therapy Poor prognosis

Question 27

What toxins cause ventilatory muscle paralysis

Answer 27

Botulism, tetanus, snake venom OPs Strychnine

Question 28

What toxins cause resp center depression

Answer 28

``` Barbituates, opiates, opioids EG Hypnotics, sedatives Tricyclic antidepressants Crude oil ```

Question 29

What is paraquat

Answer 29

Herbicide that induces oxidative damage

Question 30

Clinical signs of paraquat

Answer 30

Vomiting, burning skin, acute pulmonary edema, renal failure, coughing, pulmonary fibrosis

Question 31

Treatment of paraquat

Answer 31

Emesis, charcoal, gastric lavage, fluids, | NO oxygen unless absolutely necessary