Table: Agents and Methods of Euthanasia by Species-MSD Veterinary Manual

Agents and Methods of Euthanasia by Species

Species	Acceptable Methods^a	Acceptable Methods with Conditions^b
Aquatic invertebrates	S6.3^c: Immersion in anesthetic solution (magnesium salts, clove oil, eugenol, ethanol)	S6.3: Adjunctive methods (second step) include 70% alcohol and neutral-buffered 10% formalin, pithing, freezing, boiling
Amphibians	S7.3: As appropriate by species—injected barbiturates, dissociative agents, and anesthetics as specified, topical buffered tricaine methanesulfonate or benzocaine hydrochloride	S7.3: As appropriate by species—inhaled anesthetics as specified, CO₂, penetrating captive bolt or firearm, manually applied blunt force trauma to the head, rapid freezing of small (< 4 g [0.1 oz]) individuals where immediate death occurs
Avian species (see also Poultry, below)	S5: IV barbiturates	S5: Inhaled anesthetics, CO₂, CO, N₂, Ar, cervical dislocation (small birds and poultry), decapitation (small birds) S7.5: Gunshot (free-ranging birds)
Cats	S1: IV barbiturates, injected anesthetic overdose, Tributame, T61	S1: Barbiturates (alternative routes of administration), inhaled anesthetic overdose, CO^c, CO₂^c, gunshot^c
Cattle	S3.2: IV barbiturates	S3.2: Gunshot, penetrating captive bolt
Dogs	S1: IV barbiturates, injected anesthetic overdose, Tributame, T61	S1: Barbiturates (alternative routes of administration), inhaled anesthetic overdose, CO^c, CO₂^c, gunshot^c
Fish	S6.2: Immersion in buffered benzocaine or benzocaine hydrochloride, isoflurane, sevoflurane,quinaldine sulfate, buffered tricaine methanesulfonate, 2-phenoxyethanol, injected pentobarbital, rapid chilling (appropriate species), ethanol	S6.2: Eugenol, isoeugenol, clove oil, CO₂-saturated water (aquarium-fish facilities/fisheries), decapitation/cervical transection/manually applied blunt force trauma followed by pithing or exsanguination, maceration (research setting), captive bolt (large fish)
Equids	S4: IV barbiturates	S 4: Penetrating captive bolt, gunshot
Marine mammals	S7.5(captive): Injected barbiturates (captive) S7.7 (free-ranging): Injected barbiturates or anesthetic overdose	S7.5 (captive): Inhaled anesthetics (captive) S7.7 (free-ranging): Gunshot, manually applied blunt force trauma, implosive decerebration
Nonhuman primates	S2.3, S7.4: Injected barbiturates or anesthetic overdose	S2.3, S7.4 (as appropriate by species): Inhaled anesthetic, CO, CO₂
Poultry	S3.4: Injected barbiturates and anesthetic overdose	S3.4: CO₂, CO, N₂, Ar, low-atmospheric-pressure stunning, cervical dislocation (as anatomically appropriate), decapitation, manual blunt force trauma, electrocution, gunshot, captive bolt
Rabbits	S2.4: IV barbiturates	S2.4: Inhaled anesthetic overdose, CO₂, cervical dislocation (as anatomically appropriate), penetrating captive bolt, nonpenetrating captive bolt
Reptiles	S7.3: As appropriate by species—injected barbiturates/buffered tricaine methanesulfonate, dissociative agents with adjunctive method and anesthetics as specified	S7.3: As appropriate by species—inhaled anesthetics as specified, CO₂, penetrating captive bolt or firearm, manually applied blunt force trauma to the head, rapid freezing for animals < 4 g where immediate death occurs, spinal cord severance/destruction of brain (crocodilians)
Rodents	S2.2: Injected barbiturates and barbiturate combinations, dissociative agent combinations	S2.2: Inhaled anesthetics, CO₂, CO, tribromoethanol, ethanol, cervical dislocation, decapitation, focused beam microwave irradiation
Small ruminants	S3.2: Injected barbiturates	S3.2: CO₂ (goat kids), gunshot, penetrating captive bolt, nonpenetrating captive bolt (goat kids)
Swine	S3.3: Injected barbiturates	S3.3: CO₂, CO, N₂, Ar, gunshot, electrocution, penetrating captive bold, nonpenetrating captive bolt (piglets), manually applied blunt force trauma
Reprinted, with permission, from the AVMA Guidelines on Euthanasia 2020 Edition. Note: Initial “S” references with associated numbers in table entries refer to specific areas of more detailed information in the AVMA guidelines, available at www.avma.org/sites/default/files/2020-02/Guidelines-on-Euthanasia-2020.pdf. ^a Acceptable methods are those that consistently produce a humane death when used as the sole means of euthanasia. ^b Acceptable methods with conditions are those that may require certain conditions to be met to consistently produce humane death, may have a greater potential for operator error or safety hazards, are not well documented in the scientific literature, or may require a secondary method to ensure death. ^c Not recommended for routine use.

Species

Acceptable Methods^a

Acceptable Methods with Conditions^b

Aquatic invertebrates

S6.3^c: Immersion in anesthetic solution (magnesium salts, clove oil, eugenol, ethanol)

S6.3: Adjunctive methods (second step) include 70% alcohol and neutral-buffered 10% formalin, pithing, freezing, boiling

Amphibians

S7.3: As appropriate by species—injected barbiturates, dissociative agents, and anesthetics as specified, topical buffered tricaine methanesulfonate or benzocaine hydrochloride

S7.3: As appropriate by species—inhaled anesthetics as specified, CO₂, penetrating captive bolt or firearm, manually applied blunt force trauma to the head, rapid freezing of small (< 4 g [0.1 oz]) individuals where immediate death occurs

Avian species (see also Poultry, below)

S5: IV barbiturates

S5: Inhaled anesthetics, CO₂, CO, N₂, Ar, cervical dislocation (small birds and poultry), decapitation (small birds)

S7.5: Gunshot (free-ranging birds)

Cats

S1: IV barbiturates, injected anesthetic overdose, Tributame, T61

S1: Barbiturates (alternative routes of administration), inhaled anesthetic overdose, CO^c, CO₂^c, gunshot^c

Cattle

S3.2: IV barbiturates

S3.2: Gunshot, penetrating captive bolt

Dogs

S1: IV barbiturates, injected anesthetic overdose, Tributame, T61

S1: Barbiturates (alternative routes of administration), inhaled anesthetic overdose, CO^c, CO₂^c, gunshot^c

Fish

S6.2: Immersion in buffered benzocaine or benzocaine hydrochloride, isoflurane, sevoflurane,quinaldine sulfate, buffered tricaine methanesulfonate, 2-phenoxyethanol, injected pentobarbital, rapid chilling (appropriate species), ethanol

S6.2: Eugenol, isoeugenol, clove oil, CO₂-saturated water (aquarium-fish facilities/fisheries), decapitation/cervical transection/manually applied blunt force trauma followed by pithing or exsanguination, maceration (research setting), captive bolt (large fish)

Equids

S4: IV barbiturates

S 4: Penetrating captive bolt, gunshot

Marine mammals

S7.5(captive): Injected barbiturates (captive)

S7.7 (free-ranging): Injected barbiturates or anesthetic overdose

S7.5 (captive): Inhaled anesthetics (captive)

S7.7 (free-ranging): Gunshot, manually applied blunt force trauma, implosive decerebration

Nonhuman primates

S2.3, S7.4: Injected barbiturates or anesthetic overdose

S2.3, S7.4 (as appropriate by species): Inhaled anesthetic, CO, CO₂

Poultry

S3.4: Injected barbiturates and anesthetic overdose

S3.4: CO₂, CO, N₂, Ar, low-atmospheric-pressure stunning, cervical dislocation (as anatomically appropriate), decapitation, manual blunt force trauma, electrocution, gunshot, captive bolt

Rabbits

S2.4: IV barbiturates

S2.4: Inhaled anesthetic overdose, CO₂, cervical dislocation (as anatomically appropriate), penetrating captive bolt, nonpenetrating captive bolt

Reptiles

S7.3: As appropriate by species—injected barbiturates/buffered tricaine methanesulfonate, dissociative agents with adjunctive method and anesthetics as specified

S7.3: As appropriate by species—inhaled anesthetics as specified, CO₂, penetrating captive bolt or firearm, manually applied blunt force trauma to the head, rapid freezing for animals < 4 g where immediate death occurs, spinal cord severance/destruction of brain (crocodilians)

Rodents

S2.2: Injected barbiturates and barbiturate combinations, dissociative agent combinations

S2.2: Inhaled anesthetics, CO₂, CO, tribromoethanol, ethanol, cervical dislocation, decapitation, focused beam microwave irradiation

Small ruminants

S3.2: Injected barbiturates

S3.2: CO₂ (goat kids), gunshot, penetrating captive bolt, nonpenetrating captive bolt (goat kids)

Swine

S3.3: Injected barbiturates

S3.3: CO₂, CO, N₂, Ar, gunshot, electrocution, penetrating captive bold, nonpenetrating captive bolt (piglets), manually applied blunt force trauma

Reprinted, with permission, from the AVMA Guidelines on Euthanasia 2020 Edition. Note: Initial “S” references with associated numbers in table entries refer to specific areas of more detailed information in the AVMA guidelines, available at www.avma.org/sites/default/files/2020-02/Guidelines-on-Euthanasia-2020.pdf.

^a Acceptable methods are those that consistently produce a humane death when used as the sole means of euthanasia.

^b Acceptable methods with conditions are those that may require certain conditions to be met to consistently produce humane death, may have a greater potential for operator error or safety hazards, are not well documented in the scientific literature, or may require a secondary method to ensure death.

^c Not recommended for routine use.