Herd Health/Antibiotics

Question 1

What are the main considerations for using Antibiotics?

Answer 1

Cidal or Static?
Time or concentration dependent? 
Intracellular, extracellular, or both?
Spectrum of activity 
Water or lipid soluble? 
Restrictions?
PK/PD approach = time above MIC and AUC/MIC

Question 2

What is the rule about Sulfonamides?

Answer 2

Sulfadimethoxine is the only antibiotic that can be used on dairy cattle

Question 3

Are non-potentiated sulfas bacteriocidal or static?

Answer 3

Bacteriostatic

Question 4

Are potentiated sulfas bacteriocidal or static?

Answer 4

Bacteriocidal

Question 5

Sulfonamides

Answer 5

Time dependent
Used for mild respiratory disease and diarrhea or foot rot
Best use: Coccidiosis and the secondary invaders
Broad spectrum G+, G- and some protozoa
Action: mimick PABA precursor at the beginning of the THFA pathway blocking production of the active form of folic acid

Question 6

Beta Lactams

Answer 6

Time dependent
Bacteriocidal
Action: Bind to Penicillin Binding Protein
G- require more exposure than G+
Poor intracellular activity
Do not penetrate well into the CNS. Prostate or Uterus

Question 7

What drugs should you not use together?

Answer 7

Beta Lactam and a bacteriostatic drug

Question 8

What is the spectrum for Natural Penicillins?

Answer 8

G+
Anaerobes
select G- (Listeria) and spirochetes

Question 9

What is the spectrum for Aminopenicillins?

Answer 9

more G-

some strains of E. coli and Salmonella

Question 10

Cephalosporins

Answer 10

More g- as generation increases

Question 11

Tetracycline

Answer 11

AUC/MIC dependent
Broad spectrum and Bacteriostatic 
Action: Binds to the 30s ribosome 
Poor oral absorption 
Lipophilic 
Accumulates intracellularly 
eliminated in the feces

Question 12

Aminoglycosides

Answer 12

Bacteriocidal 
Concentration dependent 
Aerobic G-
Highly water soluble 
poor lipid soluble 
Oral absorption is poor 
Action: irreversibly binds to the 30s ribosome 
Accumulate in lysosomes and mitochondria 
Nephrotoxic and ototoxic

Question 13

Florfenicol

Answer 13

Bacteriostatic 
Time dependent 
Broad spectrum G-, some G+
Action: inhibits protein synthesis, blocks 50s ribosome 
Lipid soluble 
Concentrates in tear film 
Achieves concentration in CNS
Good penetration into diseased lung 
Binding site near macrolides = competition

Question 14

Macrolides

Answer 14

intracellular activity 
fairly broad spectrum - G- and G+ 
Action: inhibits protein synthesis by binding to 50s ribosome 
Time dependent 
Bacteriostatic
Concentrate in cells that are more acidic than plasma 
Good absorption through the gut 
Tissue concentration higher than serum

Question 15

Lincosamides

Answer 15

USED IN SWINE ONLY!

inhibit protein synthesis by binding to the 50s ribosome

Question 16

What does Lincosamides treat?

Answer 16

Mycoplasma pneumonias

Bacterial arthritis

Question 17

Fluoroquinolones

Answer 17

HIGHLY RESTRICTED! 
Bacteriocidal 
Concentration dependent 
Most G- bacteria, G+
Action: Inhibit bacterial DNA replication and transcription by binding the A subunit of DNA gyrase
Wide distribution 
Lipid soluble 
Treats Campylobacter and Salmonella

Question 18

Lactating Cow

Answer 18

a cow that is older than 20 months of age whether she has a calf or not

Question 19

Non Lactating Cow

Answer 19

A cow less than 20 months of age whether she is making milk or not

Question 20

Dry Cow

Answer 20

A lactating cow that is pulled off the milk strain and is over 20 months of age

Question 21

Who approves prescription and OTC drugs?

Answer 21

FDA

Question 22

Who approves chemical used as pesticides?

Answer 22

EPA

Question 23

What is the rule for EPA products?

Answer 23

cannot be used extra-label

Question 24

ELDU

Answer 24

Extra Label Drug Use

Question 25

AMDUCA

Answer 25

Animal Medical Drug Use Clarification Act

Question 26

ELDU is not Allowed:

Answer 26

for EPA approved products
with anti-infectives added to feed 
for production reasons 
with fluoroquinolones
with sulfonamides 
Products labeled for production purposes 
with cephalosporins
For cost or convenience 
Products not FDA approved
For non-medical use of sedatives not labeled for food animals

Question 27

NADA number

Answer 27

veterinary made purpose drug approved by the FDA

Question 28

ANADA number

Answer 28

human drug that can be used for humans or by vets and FDA approved

Question 29

MRL - Maximum Residue Level

Answer 29

Highest level of residues they will allow in another country besides the US

Question 30

First Tier of Residue Testing

Answer 30

evaluating samples per chemical compound class for each of the production classes chosen to be tested in tier 1

Question 31

Second Tier of Residue Testing

Answer 31

Focuses on samples taken at the establishment level for KIS testing

Question 32

Third Tier of Residue testing

Answer 32

Designed to target herds and flocks or origin

Question 33

What are the drugs prohibited by the ELDU?

Answer 33

Chloramphenicol 
Clenbuterol 
Diethylstillbesterol
Dimetridazole 
Ipronidazole 
Nitroimidazole
Furazolidone
Fluoroquinolones
Glycopeptides
Phenylbutazone

Question 34

FARAD

Answer 34

Food Animal Residue Avoidance Databank

Question 35

What is a Type A Article Veterinary Feed Directive?

Answer 35

Raw Product

Question 36

What is a Type B feed?

Answer 36

product that is made more concentrated and must be mixed with another medicated feed. Cannot be fed straight!

Question 37

What is Type C feed?

Answer 37

medicated feed fed as is and unadulterated

Question 38

Who enforces the Veterinary Feed Directive?

Answer 38

FDA

Question 39

What are the terms of use for a Veterinary Feed Directive?

Answer 39

Must document a need 
Must have a VCPR
Drug must be approved for species and production class
Dose, Duration, Route, and Indication 
ELDU and MUMS not allowed