WILDLIFE CHEMICAL WILDLIFE CHEMICAL IMMOBILIZATION IMMOBILIZATION 1 1 Terry J. Kreeger Terry J. Kreeger Supervisor, Veterinary Services Branch Supervisor, Veterinary Services Branch Wyoming Game and Fish Department Wyoming Game and Fish Department 2362 Highway 34 2362 Highway 34 Wheatland, WY 82201 Wheatland, WY 82201 1 Presentation prepared by N. J. Silvy Presentation prepared by N. J. Silvy
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WILDLIFE CHEMICAL IMMOBILIZATION 1 Terry J. Kreeger Supervisor, Veterinary Services Branch Wyoming Game and Fish Department 2362 Highway 34 Wheatland,
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WILDLIFE CHEMICAL WILDLIFE CHEMICAL IMMOBILIZATIONIMMOBILIZATION11
Terry J. KreegerTerry J. Kreeger
Supervisor, Veterinary Services BranchSupervisor, Veterinary Services BranchWyoming Game and Fish DepartmentWyoming Game and Fish Department
11Presentation prepared by N. J. SilvyPresentation prepared by N. J. Silvy
IntroductionIntroduction
Chemical immobilization is the use of drugs to capture or restrain animals. The term “immobilization” describes the actions of such drugs which can range from tranquilization to paralysis to general anesthesia.
Considerations-QuestionsConsiderations-Questions
►What is the species, age, sex, and physical condition of the animals being captured?
►What need to be done with or to the animals while they are restrained?
► Is physical restraint or chemical immobilization the better option?
► Is adequate assistance available?► Is the proper equipment available?►What is the local geography and landcover like?►What is the local weather on the capture days?
Characteristics of Ideal Characteristics of Ideal Immobilizing DrugImmobilizing Drug
►Wide safety margin for a given dosage►Compatible with other drugs and solutions►No adverse tissue reaction if administered intramuscularly► Short induction time► Should be reversible (with an antagonist or antidote)►Chemically stable►Concentrated to allow small volume dosage (~2–3ml)►Low cost►Not a controlled substance
Legal ConsiderationsLegal Considerations► Conditions for the use of drugs (pharmaceuticals) are established by the
Food and Drug Administration (FDA). Only 4 drugs have been specifically approved by the FDA for use on certain wild animals: carfentanil for use on cervids; xylazine for use on elk and fallow, mule, sika, and white-tailed deer; yohimbine for use on cervids (deer and elk); and ketamine for use on primates.
► However, the Animal Medicinal Drug Use Clarification Act of 1994 essentially allowed approved animal and human drugs to be used “extra label” under certain conditions. In general, those conditions are the drug: (1) approved by the FDA; (2) used by, or on the lawful written or oral order of, a licensed veterinarian; and (3) used within the context of a valid veterinarian/client/patient relationship.
►Additionally, if the animal could be consumed by a human, the veterinarian should: (1) establish a substantially extended withdrawal time (the time from the date that a drug was administered to when the animal can safely be consumed by humans); (2) be able to identify the treated animals; and (3) assure that assigned timeframes for withdrawal are met and no illegal residues occur.
Controlled Substances Controlled Substances A controlled substance means a drug that is identified in 1 of 5 schedules established by the Drug Enforcement Administration (DEA). Special regulations govern the recording and storage of these drugs. Act requires an individual to have a special DEA registration number in order to possess controlled substances.
Biologists have obtained a DEA registration number and have been able to procure drugs through veterinary product distributors. However, even though they are in possession of these drugs, they cannot use them on animals without veterinary supervision. Non-veterinarians can legally administer drugs if a valid veterinarian/client/patient relationship is established. The veterinarian does not have to be on site during the actual immobilization event, but he or she should be involved in the planning process.
Drug SchedulesDrug SchedulesSchedule I: This is reserved for experimental and abused drugs such as heroin, marijuana, and lysergic acid diethylamide (LSD). No capture drugs are Schedule I.
Schedule II (IIN): This includes most of the opioids used for animal immobilization, such as etorphine, fentanyl, sufentanil, and carfentanil and the opioid antagonist, diprenorphine.
Schedule III (IIIN): This contains ketamine and tiletamine/zolazepam.
Schedule IV: Includes benzodiazepine tranquilizers, such as diazepam and midazolam, and butorphanol.
Schedule V: This covers small, limited quantities of narcotic drugs included in preparations with non-narcotic active medicinal ingredients. No capture drugs are Schedule V.
Types of Drugs Used: Types of Drugs Used: TranquilizersTranquilizers
Usually will not cause immobilization by themselves Increase effectiveness of other agents Nearly always used in combination with other agents Examples
Types of Drugs Used: SedativesTypes of Drugs Used: Sedatives
Can induce immobilization by themselves (depending on species) Can be used in combination with other agents Produces hypnotic-like state Manipulation of sedated animal may produce arousal Examples
►Diazepam (Valium®)►Xylazine (Rompun®)
Wide safety margin but may not effect immobilization Reversible with yohimbine (Antagonil®) Readily available
Types of Drugs Used: Types of Drugs Used: Neuromuscular Paralytic AgentsNeuromuscular Paralytic Agents
Narrow safety margin Under dosage produces no effect Over dosage produces apnea (stops breathing) Not reversible Fairly readily available Examples
►Nicotine sulfate (extraordinarily narrow margin of safety)►Succinylcholine chloride (Sucostrin®, Anectine®)
►
Types of Drugs Used: Dissociative Types of Drugs Used: Dissociative AnestheticsAnesthetics
Ketamine hydrochloride (Ketaset®, Vetalar®)► Wide margin of safety► Used with a wide variety of animals► Often used with xylazine or acetylpromazine► Produces catatonia-like immobilization► Reversible with tolazoline (Priscoline®)► Readily available► May need large volumes for some species
Tiletamine and zolazepam (Telazol®)► Zolazepam is a tranquilizer, so no others needed► Wide margin of safety► Used with a wide variety of animals► Federal permit required; Schedule III controlled
substance; must be under the authority of licensed veterinarian
Phencyclidine hydrochloride (Sernylan®)► Wide margin of safety► Was the agent of choice for large
carnivores (e.g., Ursus spp.)► Can be combined with
tranquilizers► Not readily available; Schedule
II controlled substance; must be under the authority of licensed veterinarian
► Compound also known as PCP or "angel-dust"
► Human abuse potential
Types of Drugs Used: Narcotic Types of Drugs Used: Narcotic AnestheticsAnesthetics
Not readily available, controlled substances Significant risk to humans Used on a wide variety of animals, especially ungulates Can be used with other agents Reversible with naloxone (Naline®) or specific antagonists Examples
► Etorphine (M-99®) Readily reversible with diprenorphine (M-
50/50®) May require larger volumes in mega-herbivores Often used with xylazine Available with acepromazine as Large and Small
Animal Immobilon® Schedule II controlled substance; must be under
the authority of licensed veterinarian
Fentanyl Often combined with droperidol
(Innovar-Vet®) Readily reversible with naloxone Schedule II controlled substance; must
be under the authority of licensed veterinarian
►Carfentanil citrate (Wildnil®) Works well on the largest animals Readily reversible with naloxone Schedule II controlled substance; must
be under the authority of licensed veterinarian
Extremely dangerous for humans if accidentally exposed
Dose CalculationsDose Calculations
► Several factors influence dose needed Animal species Mass Age Sex Psychological state Condition
► Calculation Estimate animal mass Doses listed in mg of drug per kg body mass in reference books Syringes loaded as ml drug, so mg/ml required
Formula for Calculating VolumeFormula for Calculating Volume► The formula is:► Volume of Drug Administered = Body Weight x Dosage► Drug Concentration► ► For example, consider immobilizing an animal that weighs 80 kg (176 lb) with drug
“X”. The recommended dosage of drug X for this animal is 5 mg/kg. The concentration of drug X is 100 mg/ml. First, calculate the total mg needed for this animal by multiplying the animal’s weight (80 kg) by the recommended drug dosage (5 mg/kg):
► ► Milligrams of drug X needed = 80 kg x 5 mg/kg = 400 mg ► ► Then calculate the volume of drug solution to withdraw from the bottle by dividing
the total mg (400 mg) by its concentration (100 mg/ml):
►Hand-held syringe
► Push pole or pole syringe (easily made)
►Blow gun Limited size of dart Limited delivery volume Limited range, but accurate with practice Reduced danger of impact trauma as compared to air- and
combustion-powered guns Can be readily manufactured by user
Impact trauma not severe if proper technique used,
but still potentially dangerous
Combustion-powered gun
Pistol or rifle
Variable powder charges available
Can handle large darts (6–10 inches)
Poor range with largest darts; extended range with
smaller darts
Accurate ;can be equipped with telescopic sights
Higher potential for impact trauma than previous
delivery systems
Dart PlacementDart PlacementThe preferred areas for intramuscular injection are the large muscles of the hindquarters or the shoulder. In elk and many other ungulates, the area in the rump where the light hair meets the darker hair is a good aiming point.
Common Drugs and Their AntagonistsCommon Drugs and Their Antagonists
Moose immobilized with only opioids (carfentanil, thiafentanil, etorphine) invariably remain sternal with head up. The addition of a tranquilizer increases the probability of pneumonia because moose have a tendency to roll over and aspirate rumen contents.
Resources (web sites) for SuppliesResources (web sites) for Supplies
Animal Care Equipment and Services, Inc.
www.animal-care.com
(Dart guns, darts, blow pipes, other animal capture equipment)
Dan-Inject
http://www.daninjectdartguns.com/
(Dart guns, darts, blow pipes)
Palmer Chemical & Equipment Co., Inc.
www.palmercap-chur.com
(Dart guns, darts)
Pneu Dart, Inc.
www.pneudart.com
(Dart guns, darts, blow pipes)
Telinject USA, Inc.
www.telinject.com
(Dart guns, darts, blow pipes)
Wildlife Pharmaceuticals, Inc.
www.wildpharm.com
(North American supplier of capture drugs)
Recommended Dosages for UngulatesRecommended Dosages for Ungulates
Species Immobilizing dosage Antagonist_______________________________________________________________________________________________
Bison 0.005 mg/kg carfentanil plus 0.07 mg/kg xylazine 0.5 mg/kg plus 1 mg/kg tolazoline
Weasel 5 mg/kg ketamine plus 0.1 mg/kg medetomidine
Recommended Dosages for Other Recommended Dosages for Other Small MammalsSmall Mammals
Species Immobilization dosages____________________________________________________
Badger 4.4 mg/kg Telazol®
Beaver 10 mg/kg ketamine plus 1 mg/kg xylazine
Marmot 80 mg/kg ketamine plus 10 mg/kg xylazine
Muskrat 50 mg/kg ketamine plus 5 mg/kg xylazine
Opossum 10 mg/kg ketamine plus 2 mg/kg xylazine
Porcupine 5 mg/kg ketamine plus 2 mg/kg xylazine
Rabbit 30 mg/kg ketamine plus 6 mg/kg xylazine
Squirrel 10 mg/kg Telazol®
SUMMARYSUMMARY
► Drugs and the equipment used to administer them have Drugs and the equipment used to administer them have become more sophisticated, efficacious, and safe over the become more sophisticated, efficacious, and safe over the past half century. past half century.
► Today, capture drugs should be part of every wildlife Today, capture drugs should be part of every wildlife management professional’s armamentarium. management professional’s armamentarium.
► Although capture drugs should be used judiciously, theyAlthough capture drugs should be used judiciously, they
should always be considered as a primary solution toshould always be considered as a primary solution to
problems where animal and human safety is uppermost.problems where animal and human safety is uppermost.