Avermectins

Question 1

Avermectins are antibiotics originally from ____ ____.

Answer 1

Streptomyces avermitilis

Question 2

What are the 4 generic avermectins?

Answer 2

1. Ivermectin
2. Doramectin
3. Selamectin
4. Eprinomectin

Question 3

What are the 2 generic milbemycins?

Answer 3

1. Milbemycin

2. Moxidectin

Question 4

____ ____ is a diluent used in Ivermectin.

Answer 4

Propylene glycol

Question 5

What are the 2 constituents of Ivermectin?

Answer 5

1. Macrolide

2. Sugar molecule

Question 6

What are the 4 modes of action of Ivermectin?

Answer 6

1. Increases opening of Cl- ions
2. Allosteric modulator of ligand-gated ion channels
3. Inhibit movement, pharyngeal pumping, and egg laying in nematodes due to increased inhibitory ion-channels
4. Inhibit muscle contraction in insects because of GluCl channels present on body muscle

Question 7

Which of the following is Ivermectin effective against: Nematode adults, nematode larvae, insects, flukes, lice, fleas, filaria, mites.

Answer 7

1. Nematode adults
2. Nematode larvae
3. Filaria
4. Insects
5. Lice
6. Mites

Question 8

What is the spectrum of Ivermectin in the horse?

Answer 8

1. Bots
2. Stronglyes
3. Pinworms
4. Ascarids
5. Stomach worms

Question 9

What is the spectrum of Ivermectin in the pig?

Answer 9

1. Major GI worms
2. Lungworms
3. Kidney worms

Question 10

What is the spectrum of Ivermectin in the dog?

Answer 10

1. Microfilariae
2. Whipworms
3. Ascarids

Question 11

Is Ivermectin lipophilic or lipophobic?

Answer 11

Lipophilic

Question 12

The concentration of Ivermectin is highest in which 3 tissues?

Answer 12

1. Liver
2. Fat
3. Bile

Question 13

The concentration of Ivermectin is lowest in which tissue?

Answer 13

Brain

Question 14

____ ____ accounts for 98% of elimination of Ivermectin.

Answer 14

Fecal excretion (via bile)

Question 15

In which animal can Ivermectin NOT be used?

Answer 15

Lactating diary cows

Question 16

What is the pre-slaughter withdrawal time of Ivermectin in swine?

Answer 16

5 days (PO

18 days (SQ)

Question 17

What is the pre-slaughter withdrawal time of Ivermectin in sheep?

Answer 17

11 days (PO)

Question 18

What is the pre-slaughter withdrawal time of Ivermectin in cattle?

Answer 18

35 days (SQ)

49 days (pour on)

Question 19

True or False: Ivermectin is teratogenic.

Answer 19

FALSE - Ivermectin is safe in pregnant animals.

Question 20

Eprinomectin is a treatment for bovine ___ and ___.

Answer 20

Nematodes and ectoparasites

Question 21

What is the pre-slaughter withdrawal period for Eprinomectin in cattle?

Answer 21

There is NO pre-slaughter w/d period

Question 22

What is the milk discard time of Eprinomectin in cattle?

Answer 22

There is NO milk discard time

Question 23

What is Dectomax?

Answer 23

Doramectin

Question 24

Which is more lipophilic, Ivermectin or Doramectin?

Answer 24

Doramectin

Question 25

Which has a longer plasma half-life, Ivermectin or Doramectin?

Answer 25

Doramectin

Question 26

What is the pre-slaughter withdrawal time for Doramectin (SQ/IM)?

Answer 26

35 days

Question 27

What is the pre-slaughter withdrawal time for Doramectin (pour on)?

Answer 27

45 days

Question 28

How is Selamectin applied in dogs and cats?

Answer 28

Topically 1x / month

Question 29

What is the common name of Selamectin?

Answer 29

Revolution

Question 30

What is Selamectin 1 effective against in the dog?

Answer 30

1. Heartworm preventative 2. Fleas 3. Ear mites 4. Ticks 5. Sarcoptic mites

Question 31

What is Selamectin 1 effective against in the cat?

Answer 31

1. Heartworm preventative 2. Hookworms 3. Fleas 4. Ascarids 5. Fleas

Question 32

Selamectin 2 is more bio-available in the dog or the cat?

Answer 32

Cat (74% vs. 4%)

Question 33

What is the plasma half-life of Selamectin 2 in the dog?

Answer 33

11 days

Question 34

What is the plasma half-life of Selamectin in the cat?

Answer 34

8 days

Question 35

Which is safer, Selamectin 2 or Ivermectin?

Answer 35

Selamectin 2

Question 36

Which is longer acting, Ivermectin or Moxidectin?

Answer 36

Moxidectin

Question 37

Which is more lipid soluble, Ivermectin or Moxidectin?

Answer 37

Moxidectin

Question 38

What is the pre-slaugter withdrawal time of Moxidectin in cattle?

Answer 38

NONE when administered topically

Question 39

What is the milk withdrawal time of Moxidectin in cattle?

Answer 39

NONE when administered topically

Question 40

What is the Moxidectin preparation in the dog called?

Answer 40

Proheart

Question 41

What is the use of Proheart in the dog?

Answer 41

Oral and SQ against eartworm prevention

Question 42

What is the Moxidectin preparation in the cat called?

Answer 42

Cydectin

Question 43

What is the use of Cydectin in the cat?

Answer 43

Injectable and pour on against nematodes and ectoparasites

Question 44

What is the Moxidectin preparation in the horse?

Answer 44

Quest

Question 45

What is Milbemycin used to control?

Answer 45

1. Heartworm 2. Ascarids 3. Hookworms 4. Whipworms

Question 46

___% of a Milbemycin dose is absorbed.

Answer 46

10%

Question 47

Milbemycin can also be used in the control of demodex. What is the treatment plan?

Answer 47

1x / day at 2-3 mg/kg for 1-3 months

Question 48

True or False: Milbemycin is not to be administered to nursing pups.

Answer 48

FALSE - Milbemycin is not harmful to nursing pups.

Question 49

True or False: Milbemycin is not to be administered to pregnant bitches because of its harmfulness to fetuses.

Answer 49

FALSE - Milbemycin is not harmful to fetuses.

Question 50

Review: what is the pre-slaughter withdrawal period of pour-on ivermectin & doramectin in cattle?

Answer 50

7 weeks

Question 51

Review: what is the pre-slaughter withdrawal period of pour-on eprinomectin & moxidectin?

Answer 51

There is NO withdrawal period

Question 52

Adverse effects associated with the Avermectins are due to ____ receptor stimulation when these antibiotics get into the brain.

Answer 52

GABA