1 Zoo and Wildlife Anesth
Page 1: Introduction
Dr. Brighton T. Dzikiti
PhD, MSC, BVSc
Anesthesiology Department of Clinical Science
Ross University School of Veterinary Medicine
Focus on Anesthesia: Wildlife & Zoo
Page 2: Overview of Wildlife Anesthesia
Key Areas of Understanding:
Indications for using capture drugs in wildlife
Legal and ethical considerations regarding wildlife capture
Safety protocols during anesthesia
Commonly used drugs:
Sedatives/Tranquilizers
Potent Opioids
Cyclo-hexylamines (Dissociative anesthetics)
Antagonists
Specific drugs for different animal groups
Common equipment used
Possible complications during anesthesia
Page 3: Indications for Wildlife Capture
Types of Immobilization:
Tranquilization
Sedation
Standing immobilization
Complete immobilization
Field immobilization
Hospitalization for diagnostics or surgery
Page 4: Legal and Ethical Considerations
Regulations Vary by Location:
Countries/states have different regulations on wildlife drugs
Certification required for possession of wildlife drugs or capturing species
Risks of drug abuse by poachers
Wildlife translocation regulations
Ethical considerations in game breeding:
Animal ownership
Justification of breeding
Manipulation of genetic pool
Cautions:
Avoid legal infringements
Page 5: Safety Considerations
Importance of Safety in Wildlife Anesthesia:
Risks to people, animals, and equipment
High-risk factors:
Use of potent drugs
Dart guns as lethal firearms
Hostile environments
Unpredictable animal behavior
Page 6: People Safety Considerations
Veterinarian Responsibilities:
Effective management and communication essential
Importance of firearm handling regulations
Preventing accidental exposure to capture drugs
Best practice: pair at least two veterinarians
Awareness of risks such as thiafentanil exposure which can lead to cardiopulmonary arrest rapidly
Emergency preparedness with antagonists available (e.g., Naltrexone)
Environmental hazard awareness (e.g., snakes) and carrying first aid kits
Page 7: Animal Safety Considerations
Factors Affecting Animal Safety:
Ambient temperature extremes (heat/cold)
Exposure to noise-induced stress
Risks of injuries (lacerations, panic-related accidents)
Bloat – a significant stress response
Swift procedures to minimize animal stress
Page 8: Special Equipment for Anesthesia
Equipment Requirements:
Significant capital investment needed
Essential equipment includes:
High-quality syringes and needles
Pole syringe (3-4 meters)
Blow pipes (10-15 meters)
Dart projectors:
Pistol: 1-25 meters
Rifle: 5-60 meters
Page 9: Pole Syringe (Jab Stick)
Pole Syringe Characteristics:
Ideal for close-range use (within hand reach)
Rapid drug administration in a single jab
Versatile for different animal sizes
Page 10: Blow Pipe
Blow Pipe Features:
Manual lung-powered device
Best for smaller animals to prevent trauma from powerful darts
Limited reach and volume of drug delivery
Page 11: Dart Pistol and Kit
Page 12: Dart Rifle
Dart Rifle Features:
CO2 powered injection rifle kit, includes:
CO2 cartridges
Syringes with red tailpieces
Page 13: Darts
Characteristics of Darts:
Special syringes and needles that are sturdy and liquid-tight until impact
Page 14: Dart Projectors Overview
Dart Projectors:
Powered by:
Compressed gas systems (e.g., air, CO2)
Explosive charge systems (powder)
Require licenses for use
Understand dart impact physics for safe usage:
Impact Energy = 1/2 x mass x (velocity)^2
Importance of experience for target species to minimize tissue trauma
Page 15: Injection Sites for Dart Projectors
Page 16: Causes of Dart Failure
Common Problems in Dart Firing:
Firing Failures:
Not firing
Blocked needle
Sticky plunger
Drug Delivery Issues:
Incorrect injection site
Drug interactions affecting efficacy
Aerodynamic Factors:
Deflection during flight and environmental interferences
Animal Injury Risks:
Fractures, hemorrhage, accidental intrathoracic injections
Page 17: Commonly Used Drugs
Categories of Drugs:
Immobilizers:
Potent Opioids & Cyclo-hexylamines
Tranquilizers:
Phenothiazines & Butyrophenones
Sedatives:
Benzodiazepines & Alpha-2-adrenergic agonists
Antagonists:
For opioids & alpha-2-adrenergic agonists
Page 18: Opioids
Key Opioids:
Mu agonistic opioids such as:
Etorphine (M99)
Carfentanil
Thiafentanyl (A3080)
Suitable for large mammals (e.g., elephants)
Notable doses, e.g., 8 mg of etorphine for adult elephants
Page 19: Adverse Effects of Opioids
Major Risks:
Respiratory depression, especially in sensitive species:
White rhinoceros
Giraffe
Hippopotamus
Mini antelope
Waterbuck
Essential to manage complications:
Oxygen supplementation
Supported ventilation
Partial opioid reversal with Butorphanol
Page 20: Additional Adverse Effects
Other Concerns with Opioids:
Prolonged excitement due to under-dosing
Muscle rigidity and tremors
Hyperthermia risk due to excitement or muscle activity
Increased blood pressure and heart rate
Decreased gut mobility leading to bloat
Nausea, especially in primates and carnivores
Page 21: Renarcotization
Understanding Renarcotization:
Signs of re-sedation after opioid antagonist administration include high-stepping and decreased response
Causes include:
Inadequate antagonist dosing
Choices of antagonist with shorter half-life than agonist
Excess agonist leading to receptor imbalance
Interventions:
Repeat antagonist doses can be administered via dart
Page 22: Opioids in Wildlife (Summary)
Types of Opioid Drugs:
Mixed agonist-antagonists:
Diprenorphine (M5050)
Pure antagonists:
Naloxone
Naltrexone
Nalmefene*
Agonists:
Etorphine (M99)
Carfentanil
Thiafentanil (A3080)
Fentanyl
Page 23: Cyclo-hexylamines (Dissociative anesthetics)
Commonly Used Drugs:
Ketamine (Ketaset)
Tiletamine (in Telazol)
Effective for immobilizing feral carnivores (felids and canids)
Page 24: Tiletamine-Zolazepam (Telazol)
Characteristics of Telazol:
Combination drug of higher potency than Ketamine
Excitement during recovery possible; low dose preferred with Dexmedetomidine support
Page 25: Tranquillizers
Uses of Butyrophenones and Phenothiazines:
Adjuncts to opioids for large mammal immobilization
Reduce stress for captive herbivores
Common adverse effects:
Extrapyramidal signs such as ataxia and tremors
Page 26: Butyrophenones
Examples of Butyrophenones:
Azaperone
Haloperidol
Page 27: Phenothiazines
Examples of Phenothiazines:
Acetylpromazine (ACP)
Propionylpromazine
Long-acting drugs such as Zuclopenthixol acetate
Perphenazine enanthate
Page 28: Tranquillizers: Onset and Duration
Onset & Duration Details:
Azaperone: Onset 15-30 mins, Duration 2-4 hrs
Haloperidol: Onset 15-30 mins, Duration 8-12 hrs
Acepromazine: Onset 15-30 mins, Duration 6-8 hrs
Zuclopenthixol acetate: Onset 1-2 hrs, Duration 1.5-3 days
Perphenazine enanthate: Onset 12-36 hrs, Duration 7-10 days
Page 29: Sedatives - Benzodiazepines
Benzodiazepines Used:
Midazolam
Diazepam
Zolazepam
Page 30: Diazepam Specifics
Diazepam:
Can be mixed with ketamine in one syringe
Recommended IV route due to irritant properties for IM or subcutaneous injections
Usage variations based on species (carnivores vs herbivores)
Midazolam:
More potent option, multi-route administration capable
Page 31: Zolazepam Information
Zolazepam:
Mixed with Tiletamine as Zoletil/Telazol for carnivore immobilization
Page 32: Sedatives - Alpha-2 Adrenergic Agonists
Examples:
Xylazine
Medetomidine
Dexmedetomidine
Detomidine
Romifidine
Page 33: Xylazine Specifics
Xylazine:
Older, inexpensive, used widely
Duration of action 1-2 hours, analgesia for 30 minutes
Antidotes available:
Yohimbine and Atipamezole
Dexmedetomidine:
Faster onset and more potent than Xylazine
Ideal for carnivores
Detomidine:
More effective in herbivores
Romifidine:
Effective without causing much ataxia in herbivores
Page 34: Specific Alpha-2 Antagonists
Antagonists for Sedatives:
Atipamezole (Antisedan)
Yohimbine
Tolazoline
Routes vary; dosing adjustments needed based on time lapsed and animal response
Page 35: Drug Combinations
Common Combinations:
Use of 2 or 3 drugs based on:
Species type
Availability
Anesthesia reason
Ideal Drug Attributes:
High potency
Quick onset
Safety profile
Minimal adverse effects
Page 36: Drug Combinations by Species
Summary of Drug Combinations:
Large Mammals: Potent Opioids + Tranquilizers
Smaller mammals: Potent Opioids + Tranquilizers or Ketamine/Telazol with alpha-adrenergic agonists or Benzodiazepines
Carnivores: Ketamine/Telazol with alpha-adrenergic agonists or Benzodiazepines
Primates: Ketamine/Telazol with alpha-adrenergic agonists or Benzodiazepines
Page 37: Drug Combinations for White Rhino
Considerations for White Rhino:
Large structure and sensitive to opioids
Common complications include:
Muscle tremors and rigidity
Hypoventilation and hypoxemia
Immobilization Dosing:
Etorphine + Azaperone, supplemented with Ketamine/Isoflurane
Page 38: Drug Combinations for Black Rhino
Dynamics of Black Rhino:
Smaller body mass and lower respiratory depression with opioids
More excitable and aggressive than White Rhino
Immobilization Dosing:
Similar opioid + Azaperone dosing strategy as White Rhino
Page 39: Drug Combinations for Elephants
Special Considerations for Elephants:
Large, dangerous, special respiratory considerations
Specific drug combinations including:
Etorphine + Azaperone, monitored for effectiveness
Page 40: Drug Combinations for Red Deer
Capture Protocol:
Example combinations include Xylazine + Ketamine or Medetomidine + Ketamine
Page 41: Drug Combinations for Coyote
Coyote Protocols:
Ketamine dosing resulted in excessive salivation and rigidity
Combined drugs recommended for better results: Telazol + Xylazine
Page 42: Wild Dogs Immobilization
Wild Dogs:
Drug combination of Fentanyl + Xylazine recommended
Fully reversible regimen with established dosing
Page 43: Bear Protocols
Bear Immobilization Regimens:
Mixtures of Xylazine/Ketamine with flexibility in dosages
Enhancement of absorption via addition of Hyaluronidase
Page 44: Primates Anesthesia Techniques
Primate Protocols:
Oral sedation for immobilization is beneficial
Using Ketamine with alpha-2 adrenergic agonists or benzodiazepines
Page 45: Monitoring During Anesthesia
Monitoring Capabilities:
Challenges due to unique animals/environments
Essential observations and portable monitors for assessing respiration and oxygenation
Page 46: Common Complications
Potential Complications Include:
Trauma from darts or environmental objects
Respiratory failure:
Hypoventilation
Hyperthermia or Hypothermia
Capture Myopathy
Bloat/Regurgitation
Stress and Shock
Maladaptation: managing symptoms as necessary
Page 47: Capture Myopathy Overview
Recognized Syndromes:
Acute Death Syndrome: hyperthermia, acidosis
Delayed Death Syndrome: death after 24 hours
Ataxic-Myoglobinuric Syndrome: acute renal failure
Muscle-rupture Syndrome: hyper-flexion of hocks
Page 48: Capture Myopathy and Release
Causes and Effects:
Muscle breakdown from over-exertion leading to systemic issues
Urgent need to manage stress during capture
Page 49: Stress Management**
Best Practices:
Reduce capture time
Maintain average temperatures
Fluids and sedatives if required
Page 50: References
Primary Reference:
Lumb & Jones’ Anesthesia and Analgesia, 4th Edition, 2007
Dr. Michelle Miller, University of Stellenbosch, South Africa
Dan-inject.com
Page 51: Conclusion
Thank You!
Questions welcomed
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