LA Ectoparasite Control

Question 1

Tx for orf?

Answer 1

ABx/antibacterials

• C+S where possible
• NSAIDs used more frequently

Question 2

Tx flystrike?

Answer 2

Pyrethroids 
- extoparaciticides (-> paralysis)
- lic sheep and cattle
- SynthPyreths (SP) are the only licensed TREATMENT of flystrike 
IGRs (Cyromazine, Dicyclanil)
- licensed to PREVENT flystrike

Question 3

What is sheep scab?

Answer 3

Mite (psoroptes ovis) infection -> loss of wool

Question 4

Tx mites? (Sheep scab) Mechanimsms of action?

Answer 4

• Pyrethroids

- Organophosphate sheep dips (AchE R blocking, highly toxic to all spp. DIazinon only UK approved active ingredient)

Question 5

What precautions must be taken when using organophosphates?

Answer 5

• competent operators
• no spray jets (dip only)
• dispose using lic contractor
• enzymatic environmental degraders can be added
• do not leave overnight!! -> Post dipping lameness due to infection with E. Rhusiophatiae

Question 6

Tx sheep lice?

Answer 6

> Macrocytic lactones (/Avermectins):

• internal and external parasites (endectocide)
• glutamate gated Cl channels
• flaccid paralysis of pharynx
• easy to administer cf. organophosphate dips
• Interfere with worm control programmes!*
• Organophosphates

Question 7

Tx ringworm?

Answer 7

> antifungals (enilconazole only LIc product) 
- blocks synth of ergosterol 
- \$\$$!!! Vax may be more cost effective 
> permethrin 
> Amitraz imported from another country

Question 8

If importing a drug from another member state for use in a food producing animal what must it be authorised for?

Answer 8

• use in food spp. in other country
• have MRLs (min residue levels)
• prescribing vet gives withdrawal period, but usually minimum regulation period used!

Question 9

ROA macrocytic lactones?

Answer 9

oral or injectable

Question 10

How can sheep scab (mites) be differentiated from lice on observation?

Answer 10

It cant!

Question 11

In general, which drugs are licensed for sheep?

Answer 11

All

Question 12

In general, which drugs are licensed for cattle?

Answer 12

All but organophosphates

Question 13

In general, which drugs are licensed for pigs?

Answer 13

Only Avermectins/macrocytic lactones

Question 14

In general, which drugs are licensed for chickens?

Answer 14

None