Euthanasia

"good death" ending life that eliminates pain and distress

Orthotanasia

“right death” → not artificially extend the dying process

Unconsciousness

loss of awareness → brains ability to receive an integrate information is disrupted

Sedation x anesthesia

animal still arousable while sedated, whereas it shouldn’t be if anesthetized

Humane slaughter

killing animals for commercial reasons

Depopulation

rapid destruction of several animals

What drugs should we not use in conscious animals?

Neuromuscular blocking drugs should never be used, some exceptions may apply in certain medical procedures.

Agonal breath

gasping is a brainstem reflex in response to hypoxia, last respiratory pattern prior to terminal apnea

Post mortem twitching or movement

muscles and nerves go through short phase hyperexcitability

Death mechanisms

• direct depression of neurons necessary for life

• hypoxia

• physical disruption of the brain activity

Drugs used that cause Direct depression of neurons

Depression of cortical neuronal system leads to loss of consciousness followed by respiratory and cardiac arrest

• Inhalants

• Barbiturates → Sodium Pentobarbital → IV → most common

• T-61 → embutramide, mebezonium, and tetracaine hydrochloride

• MS-222

• Potent opioids

• Ketamine/a₂ adrenergic combinations

• Ethanol

Drugs used that cause Hypoxia

Exposing animals to hihg conc of gases that displace O2. Impair oxygen transport by hemoglobin

• CO₂

• N₂ and Argon → for chickens, turkeys, pigs

• Carbon monoxide

Physical methods for euthanasia

Destruction of midbrain centers → bilateral lesion of the rostral pons → mostly for large animals or production

• Stunning

• Captive bolt

• Gunshot

• Cervical dislocation

• Electrocution

• Exsanguination

Other methods to euthanize

Not for awake animals

• Potassium chloride and magnesium salts

• Neuromuscular blocking agents

How to confirm death

• no pulse

• no heartbeat

• no corneal reflex

• grey mm

• rigor mortis

What should we use for euthanizing companion animals?

IV injection of Pentobarbital

• IV when possible

• IP in small animal

• IC, Intrahepatic, Intrarenal only in unconscious animal

What should we use to euthanize a horse?

• Pentobarbital → (xylazine + ketamine

  ± diazepam)

• Penetrating captive bolt

• Adjunct methods after anesthesia

• Neuromuscular blocking agents when the horse is dangerous and fractious

What should we use to euthanize ruminants?

• Barbiturates

• Captive bolt or gunshot

What should we use to euthanize swine?

• overdose barbiturates

• CO₂, Ar, N₂, gas

• gunshot

• caprive bolt

• electrocution

• blunt force trauma

What should we use to euthanize poultry?

• inhaled gas

• physical methods

What should we use to euthanize amphibians and reptiles?

• Pentobarbital

• MS-222

• then use adjunctive methods → blunt force trauma, decapitation

• hypothermia is NOT unacceptable