Lecture 7: use of drugs in food producing animals Flashcards
What are the three uses for drugs in food animals
- Prophylactic (individual) or metaphylaactic (herd) prevention or morbidity/mortality
- Treat illness
- Increase production
What drug is commonly used to increase production and food animals and why dont we want to do this
Antibiotics increase production so don’t do this because antibiotic resistance
When a drug is administered to any animal, we indirectly administer that drug and its metabolites to our ___ and ____
Clients and local environment
What are the two negative effects of drug use on the food chain
- Risk of exposing population at large to drug and its metabolites (health risk)
- Risk of administering that drug and its metabolites to the environment/downstream commercial processes (economic risk)
What is chloramphenicol
Broad spectrum antibiotic that crosses the blood brain barrier and placenta
When do you want to use chloramphenical in food producing animals
NEVER!
Why can you never give chloramphenicol to food producing animals
Causes non-regenerative fatal aplastic anemia in 1:35,000 humans
What is enrofloxacin
Broad spectrum antibiotic of the fluoroquinolone class
What cows can you not use enrofloxacin in and why
May not be used in LACTATING dairy cows- antibiotic kills bacteria used in dairy product manufacturing
Dry dairy cows are included
What is a food animal
Any animal from which a tissue or other product has the POTENTIAL to enter the human food chain
Are pet pigs that the family does not intend for food classify as a food animal
Yes! Although families intent is not to eat the animal it still has POTENTIAL to enter food chain
What are the major food animals
Cattle, swine, chickens, and turkeys
What is FARAD
Food animal residue avoidance database
In order for a food animal that was prescribed a drug that was used extra label what must the veterinarian know
The withdrawal time, therefore can determine when the animal can enter the food chain
What does federal government use to tract drug use
A/NADA- approved/new animal drug application
Each drug is given a specific number
Can enrofloxacin be used extra label in food producing animals
No!
What is tolerance
Concentration of a drug/metabolite measured in the target tissue below which any or all food products of that animal are considered to have total drug and levels that are safe for consumption
What is a maker residue
Metabolite of the parent drug
What is considered target tissue when measuring tolerance
Edible tissue, usually the liver or kidney (involved in metabolism and excretion)
In order for a food animal to be considered safe for consumption does the concentration of the drug need to be above or below tolerance
Below!
T or F: Milk and eggs serve as their own makers therefore veterinarians can examine a dozen eggs/amount of milk and have those tolerance levels be representative of while lot
True
What determines safe for consumption
Animal studies that evaluate carcinogenic potential, systemic reproductive and developmental toxicities, potential to cause antibiotic resistance,
Determining an acceptable daily intake of drug/metabolite in a human diet, assuming high amounts of consumption
What is food animal residue
A drug or regulated metabolite identified in a defined target tissue that is at or above the tolerance
If food residue is detected what happens next
Deemed unsafe for consumption, animal is condemned and does not enter food chain
What department does FDA fall under
Department of health and human services
What organizations are responsible for regulating drugs, feeds, and medical devices for tolerance
FDA, Center for Veterinary medicine, and EPA
What agency does the Center for Veterinary medicine fall under
FDA
What acts empower the FDA to enforce tolerance
FD & C and AMDUCA
What department does FSIS fall under
USDA
What does the national residue program fall under
USDA-FSIS
What agencies are responsible for the testing/reinforcement of tolerance levels
USDA-FSIS and national residue program
What acts empower the USDA-FSIS and national residue program to test and enforce laws of tolerance
- Federal meat inspection act
- Federal poultry inspection act
- Federal insecticide, fungicide and pesticide Act
What is the tolerance for enrofloxacin in cattle
100ppb
What is the acceptable daily intake of enrofloxacin in humans
3ug/kg bwt/day
What is the target tissue for enrofloxacin in cattle
Liver
What is the marker residue for enrofloxacin in cattle
Desethylene cirpofloxacin
Why is desethylene ciprofloxacin the marker residue in cattle for enrofloxacin meanwhile in swine the marker in enrofloxacin
Enrofloxacin disappears from cattle muscle, tissue and fat very quickly, but desethylene cirpofloxacin remained which is the active ingredient in enrofloxacin
What is the tolerance of enrofloxacin in swine
500ppb
What is the target tissue for enrofloxacin in cattle
Liver
What is the marker residue for enrofloxacin in swine
Enrofloxacin
Wha is withdrawal time
Time required for a drug or metabolite to be below tolerance level in the 99th percentile of the population with 95% confidence
For every drug used in food animals what are the 5 things the CVM (under FDA) regulates
- Species
- Indication for use
- Dose
- Route of entry
- Interval of administration
What does the following for every drug tell us about the withdrawal time: species, indication for use, dose, route of entry, interval administration
Tells us about that pharmacokinetics so we can predict withdrawal time because we should know the 1/2 life of a drug that has an indicated use in a particular species at a certain dose
What is the withdrawal period for enrofloxacin
28 days
The withdrawal period for enrofloxacin is 28 days, what does these mean for slaughter timeline
Animals who received treatment can’t be slaughtered until after 28 days, if you want to ensure more cattle enter food chain and don’t get condemned, wait longer than 28 days
What are the two drug categories are of greatest concern because they are most commonly in violation and represent the greatest risk of exposure
- Pesticides, fungicides, and insecticides
- Antibiotics
Why do pesticides, fungicides and insecticides pose the greatest risk for entering food animal and food chain
Spread liberally and hard to control which animals get exposed
What is GRAS
Additives that can be given to animals without regulated are on the GRAS list- Generally regarded as safe
GRAS includes what items that are fed to animals
- Mineral additives to feeds
- Adjuvants added to pesticides
What drugs are prohibited for use in food-producing animals (NEVER!!)
- DES-diethylistibesterol
- Chloramphenicol
- Nitriomidazoles (metronidazole)
- Nitrofurans
- Clenbuterol
- Dipyrone
- Glycopeptides
- Gentian violet
- Phenylbutazone in adult dairy cattle
- Antiviral compounds in poultry (adamant and and neuroaminidase inhibitors)
What drugs are prohibited from EXTRA-LABEL use in food producing animals
- Sulfonamides in adult dairy cattle
- Fluoroquinolones
- Medicated feeds
- Indexed drugs
- Cephalosporins
What is the veterinary feed directive final rule
- Intends to limit antibiotic use for therapeutic instead of production purposes
- recommends drug manufacturers voluntarily stop labeling drugs as promoting animal drug
- ELDU of antibiotics or other drugs in feed requires a VCPR before a veterinarian directs compounding
