Farm animal therapeutics Flashcards
What is a category A product in the new EU antibiotic classification system?
Products that are not licensed for food producing animals, may be used in companion animals
What is a category B product in the new EU antibiotic classification system?
Critically important, avoid using these, required to have culture and sensitivity data to support your selection
What is a category C product in the new EU antibiotic classification system?
Use of these may cause a mutation that causes loss of efficacy, or total resistance of category A and B antibiotics. We want to be cautious and only use these when we need to
What is a category D product in the new EU antibiotic classification system?
Used initially before going up into the other categories
When no authorised product exists for a condition affecting a non food-producing species, and in order to mitigate unacceptable suffering, treat the animal(s) in accordance with the following sequence:
1) A veterinary medicine authorised for use in another species, or for a different condition in the same species
2i) A medicine authorised in the UK for human use
2ii) In accordance with an import certificate, a medicine authorised in another member
3) A medicine made up at the time on a one-off basis by a veterinary surgeon or an authorised person
What are the principles of the cascade in food producing animals?
- Restricted to single holding
- Medicine imported must be authorised for food-producing species in other state.
- Vet specify appropriate withdrawal period
- Vet must keep specified records (inc withdrawal)
What are antibiotics?
- Developed by bugs to fight each other
- Arms race – resistance develops, new substances evolve
- Man has synthesised new versions and ways to block resistance
- Bugs fight back
- More use = more selection pressure
How do antibiotics work?
- Disrupt cell wall production
- DNA action inhibitors
- Protein synthesis inhibitors
- Cell membrane function
Name 3 antibiotics that disrupt cell wall production
Beta - lactams, Penicillins, Cephalosporins
Name 2 antibiotics that are DNA action inhibitors
Potentiated sulphonamides
Fluoroquinolones
Name 3 antibiotics that are protein synthesis inhibitors
Streptomycin, Tetracyclines, Macrolides
What are some considerations when prescribing antimicrobials?
- Does the diagnosis warrant antibiotic therapy ?
- What organisms are involved ?
- What is the in vitro antibiotic sensitivity of the organism ?
- In what region of the body and in what cell is the organism located ? Will the antibiotic penetrate to the organism?
- What side effects might be expected ? Do the benefits outweigh the risks?
- Is this the most cost-effective therapy?
Do penicillin and beta-lactams penetrate serum or tissues? why?
Penicillins and beta lactams are acidic so they stay in the serum and don’t get into acidic milk
Does Tylan 200 penetrate serum or tissues? why?
Tissues - alkaline
Levels in milk exceed serum
Define synergism
Potentiation of one drug action by another
