T2

Veterinarians are often faced with the need toeuthanatize birds in order to relieve sufferingwith minimal pain and distress. It is imperativethat the veterinarian be knowleag"ufi" andskilled

.in appropriate euthanasia techniquesappropriate to the species. These caveats alsoapply to non-veterinary personnel that performeuthanasia under remote field conditiorrs orduring_ emergencies, such as during di."ur"control programs or following envilnmentaldisasters.

The choice of euthanasia method for birdsshould ensure, to the best degree possible, thatloss of consciousness occurs quickly, withoutapprehension or distress, and thit the method isreliable and irreversible. The method should alsobe safe for personnel to administer.

. To a large extent, the choice of euthanasiamethod for birds depends upon the fype of birdand the setting. For example, individual avianpatients in a clinical or research setting may behandled differently from flock o, uuiur{ irmals.Birds encountered in field setting.

-uy need to

be handled with another set of e"uthanasiaprotocols.

INDIVIDUAL BIRDS IN A CLINICAL ORRESEARCH SETTING

The choice to euthanatize abird, should beapproached carefully. The welfare of the birdshould always guide the process. Owners, ifpresent, should be prepared for what willhappen. The veterinarian should be prepared to

46

Birds

SUSAN OROSZ

vian veterinarians are charged withll.1ng for companion birds, Lboratorybirds, poultry, and wild birds.

provide supportive and sensitive communicationand options to the owner. Veterinarians and theirstaff also may be affected by both the emotionalconsiderations of euthanasia and with the ethicaldimensions of euthanatizing a particular bird.Ethical_ and legal considerations will beespecially prominent for birds representingendangered or threatened species.

Chemical Methods of Euthanasia

A number of protocols may be used in aclinical setting, particularly in birds that are illand when owners $/ant to be present duringeuthanasia. Injectable forms of butorphanol arerecommended to reduce pain and iistress inclinical and research settinss.

Inhalants

^ Inhalants may be used as premedications

for euthanasia at the discietion of aknowledgeable veterinarian. Inhalant anesthesiaallows for immobil jzation and a smootte, pfaneof anesthesia because using barbiturates as thesole agent for euthanasiamiy otherwise result inwing flapping, a perception of struggling otheruntoward movements, or vocaliiations.Acceptable inhalant anesthetic agents includeisoflurane and sevoflurane.

Barbiturates

^ A wide range of barbiturates are available

.for- . performing euthanasia. norug" of

barbiturates will vary on species, ug., uni healthstatus of the bird. Barbiturates can-piecipitate in

tissues and administration of barbiturate dosessignificantly above those needed to cause deathcan adversely affect post-mortem pathology.

The veterinarian (or trained personnelunder the direction of a veterinarian) should beexperienced in administering barbiturates inbirds. The barbiturate overdose may beadministered by intravenous, intraosseous, orintracardiac means or by injection into the liveror muscle. Barbiturates commonly used forparenteral administration are available as sodiumsalts that are alkaline and can irritate tissuesthereby resulting in pain. Therefore, intravenousadministration of barbiturates is preferable,when possible. Intracardiac injection ofbarbiturates is difficult if the clinician is notpracticed in the technique and may be offensiveto an observing owner. Birds should be deeplyanesthetized before intracardiac or intraosseousinjection. Intracoelomic administration is notrecommended as barbiturate absorption via thisroute is delayed due to the presence ofair sacs.

Gentle restraint and careful handling shouldbe used during euthanasia. The choice will varydepending on the bird (e.g., canary or ostrich),but restraint should be performed by aknowledgeable person to avoid distress to thebird or injury to either the bird or personnel.The bird should be monitored during euthanasiato monitor the process and ensure its properadministration. It is also essential that death beverified after euthanasia to avoid inadvertentdisposal of a living bird that is in deep narcosis.

FLOCK OR AVIARY SETTINGS

In small numbers, birds from an aviarysetting may be handled as individual avianpatients; however, it may not be practical toemploy methods used for individuals onoccasions where multiple numbers of birds needto be euthanatized. Positive test results forinfectious diseases such as Exotic Newcastle'sdisease or avian influenza may requiredestruction of an entire aviary or flock. In suchcases, large numbers of birds will need to beeuthanatized.

Birds

Chemical Methods of Euthanasia

Inhalants

Halothane, Isoflurane or Sevoflurane

In flock or aviary settings, a large, closedchamber containing halothane-, isoflurane- orsevoflurane-safurated cotton is preferred.Halothane is not advised for the anesthesia ofbirds due to its narrow margin of safety, andmay therefore be selected for euthanasia on thisbasis and because of its reduced cost, comparedto other inhalant anesthetic agents. For socialbird species where multiple individuals can beplaced in the chamber simultaneously withoutcausing distress, multiple animals can besimultaneously and humanely euthanatized withthis method. The expense of this method forflocks or for birds with larger body sizes is aconsideration that may limit its use.

Carbon Dioxide and Carbon Monoxide

Carbon dioxide (COt and carbonmonoxide (CO) are both used to euthanatizebirds in flock or aviary settings and can be usedunder field conditions. Regardless of which isused, they should be administered fromcompressed gas cylinders in order to regulateinflow to chambers with precision and to ensureadequate rapid effective gas concentrations.

Administration of CO2 reQuires completefilling of a chamber that can contain the COz at ahigh concentration without dilution from theenvironment. As CO2 is heavier than ambientair, failure to completely fill the chamber canpermit some birds to avoid exposure bybreathing air at the top of the chamber. Carbondioxide is effective with small sized birds.Hatchling birds are more resistant to the effectsof anoxia and will require higher concentrationsof COz for a longer period of time (Reilly,200I). Euthanasia with COz may take more timethan other methods. Carbon dioxide inducesinvoluntary violent respiratory efforts in birdsafter loss of consciousness, and this may beunacceptable for observers.

Special safeguards must be taken with COto prevent exposure to personnel because it islethal, odorless and cumulative in effect at

Guidetines for Euthanasia of Nondomestic Animals

relatively low levels (AVMA, 2001)' Efficient

exhaust or ventilation systems that disperse CO

to well ventilated areas should be used to avoid

exposure. Personnel should be knowledgeable

about the risks of CO and trained in its proper

administration. Carbon monoxide can become

explosive if concentrations exceed 10%

(AVMA, 2001), so gas levels should be

carefully monitored. European (Close et al',

1997) and, AVMA (AVMA, 2001) euthanasia

guidelines highlight the dangers of CO to

personnel, and CO euthanasia of birds is not

ionsidered acceptable under Australian and New

Zealand euthanasia guidelines (Reilly, 2001)'

Therefore, CO euthanasia of birds should be

considered only under rare circumstances where

alternatives are not accePtable.

Physical Methods of Euthanasia

Cervical Dislocation

For nondomestic, small birds (<100 grams

in weight), cervical dislocation may be used as a

method of euthanasia. Personnel must be trained

and proficient in the technique (Close et al',

1997; Rei l ly,200l) .

FIELD SETTINGS

In working with wild birds, a wide range of

species may be encountered under dynamic field

ctnditions. Capture techniques sometimes lead

to injuries, and captured birds might sustain

injuries that prevent release to the wild' While

-Lutt should be sought to plovide for a

continued, comfortable existence for injured

wild birds, this may not always be practical and

euthanasia may be required. In addition,

personnel may need to reduce populations of

wild birds for management like limiting disease,

or nuisance animal control' In such cases, field

euthanasia may be required.Wild birds range tremendously in size,

which presents challenges for euthanasia' The

preferred method for field settings is a large,

closed chamber containing isoflurane- or

sevoflurane-saturated cotton. Chambers or other

enclosures containing CO2 ma] also be used' In

avian disease outbreaks, large numbers of

poultry have been euthanatized by tenting with

48

plastic and gradually flooding with CO2 until the

concentration is >40oh (OIE, 2005).Where inhalants are not practical or

sufficiently rapid for euthanasia, barbiturates

may be administered alone, or preferably, in

combination with butorphanol. Proper restraint

and administration of barbiturates in wildlife

species requires trained and experienced

pirsonnel, as well as appropriate permits for the

use of controlled substances. The availability of

controlled drugs is often limited for personnel

performing avian euthanasia under field and

some other circumstances, and this can limit the

use of this method. Carcasses containing

barbiturates, opioids and some other drugs

should be disposed of such that the potential for

secondary toxicity to scavengers is prevented'

Other methods may be used conditionally'

Cervical dislocation may be used for birds up to

3 kg (Close et a1.,7997). but alternatives should

be used wherever possible to limit pain and

suffering as birds are not rendered immediately

insensible by this method. Decapitation offers

advantages over cervical dislocation under field

conditions, including exsanguination and clear

evidence of a successful procedure. Concussion'

if performed by trained and skilled personnel,

and carried out by a hard blow to the head of

birds <250 g resulting in immediate death, is

conditionally acceptable where superior

alternatives are not available (Close et al', 1997)'

Gunshot may be used in field settings to end

distress and pain, but this is recommended as a

last resort.Thoracic compression has been used

historically for birds in the freld (Gaunt, 1999)'

but this method of euthanasia is not

recommended due to concerns about the

efficacy, prolonged duration of the procedure,

the poteniial for distress of the bird, and the

perception of Pain.

EMBRYOS AND EGGS

By 50% gestation, the neural tube of avian

embryos has sufficient development for pain

perception (Reilly, 2001). Avian embryos older

ihan -

50% gestation must be killed using

decapitation, overdose of anesthetic, or other

methods considered appropriate for hatched

birds (Close et al', 1997). Earlier works have not

l-ntil the

nl orturates:lY, inrstrainttildlifeiencedlor thelity of;onnelI andrit theliningdrugsal for:d.nally.up toiould

andatelyrffersfieldclearsion,nnel,doft, iS

lrior

'97).endasa

clearly defined whether eggs young er than 50%ogestation should be euthanatized accordins toany particular standards. Consequently, inaddition to methods appropriate foreuthanatizing hatched birds, freezing ispresumed to be a humane method ofeuthanatizing avian embryos, but furtherconsideration of this is warranted.

Under field conditions, destroying theviability of eggs (,,egg addling',) may be animportant population control method fo, ,o-"species. This may entail shaking, puncturing,freezing, or coating of eggs with-oil (HumaneSociety of the United States, 2004). Where thelatter method is elected, the USOaZepruSrecommends l00o/o food_grade corn oil as ameans of euthanatizing developing avianembryos under field condirions gSO,{, 2001).Corn oil used for this application is exempt fromEnvironmental protection Agency reguiations,and this method blocks egg shiil p-ores andasphyxiates developing embryos with minimallmpact on adults. particular attention must begiven to application method, quantity of oil?pli_ed for a given species, stage of eggdevelopment at which the applicattn o""u.r,and avoidance of contact with non_target speciesand their eggs. It is essential that alpropriatepermits be obtained for any egg addling method,?9 that permit requirements be- strictlyfollowed.

REF'ERENCES

American Veterinary Medical Association(AVMA). 2001.2000 Report of rhe AVMAPanel on Euthanasia. J. Am. Vet. Med.Assoc. 218 (5):669-696.

Birc

Close, 8., K. Banister, V. Baumans, E._l\Bernoth, N. Bromage, J. Bunyan, VErhardt, p. Flecknell, N. Greeorv. FHackbarth, D. Morton and C. Wu*irf1997. Recommendations for euthanasia cexperimental animals: pafi 2. Lab. Anin3l:1-32.

Gaunt, A.S., and L.W. Oring (eds). IgggGuidelines to the Use of WitO

'giras ir

Research. The Ornithological CouncilWashington D.C. pp. 66.

Humane Society of the United States. 2004Canada Goose Egg Addling protocolMarch 2004. Washington, D.C.

Leach, M.C., V.A. Boweli, T.F. Allan, and D.BMorton. 2002. Aversion to gaseouseuthanasia agents in rats and mice. Comp.Med.52:249-257.

Office International des Epizooties (OIE) WorldOrganization for Animal Health.' 2005.Terrestrial Animal Health Code part 3.Section 3.7. Chapter 3.7.6. Guidelines for

killing of animals for disease purposes.Reilly, J.S. (ed). 2001. Euthanasia oi Animals

Used for Scientific purposes. Australianand New Zealand Council for the Care ofAnimals in Research and Teachins.Adelaide Universiry, Adelaide, Sorii,Australia. 106 pp.

U.S. Department of Agriculture (USDA) Animaland Plant Health Inspection Service. 2001.Egg oil: an avian population control tool.Technical Note, Wildlife Services.

nedee),notthelre,the

lan

ainler

CURRICULUM VITAESusan E. Orosz, PhD, DVM, Diplomate ABVP, Avian Practice and Diplomate, European College of Avian Medicine and Surgeryhttp://www.birdexoticpetvets.com/index.php?option=com_content&task=view&id=3&Itemid=93&limit=1&limitstart=3Education:1972-1976Heidelberg College, Tiffin, OhioDegree: Bachelor of Science in BiologyMagna Cum Laude

1976-1980 University of Cincinnati, College of Medicine, Cincinnati, OhioDegree: PhD, Neuroanatomy

1980-1984The Ohio State University, College of Veterinary Medicine, Columbus, OhioDegree: DVMPublications, Presentations, and Lectures:In the past 5 years alone—presented over 60 papers at international, national and regional conferences on a wide range of subjects. Innovative talks have included the invited lecture, Social and Structural Enrichment Principles of Common Avian Species, Scientists Center for Animal Welfare (SCAW 2002), Screening of Companion Birds for Use in Therapeutic Interventions (AVMA and Eden Foundation 2002), The Senses Of Birds: Their Unique Qualities (European College of Avian Medicine and Surgery, Arles, France, 2005), Self-injurious Behavior (SIB) of Primates as a Model for Feather Damaging Behavior (FDB) in Companion Psittacine Birds (co-presented with Delaney, AAV Conference, 2003), Avian Nutrition Revisited: Clinical Perspectives (AAV Conference, 2005), Assessment of an Enteral Diet for Critical Care (European College of Avian Medicine and Surgery, 2001, Munich, Germany), and Common Herbs and their Use in Avian Practice (AAV Conference, 2006).AAV:Past president of AAV and served on a number of committees since becoming a member in 1984. Currently, member of the Avian Welfare Committee, presented an Overview of the Human Companion Bird Bond and Birds in Care Facilities at the Conference in Rhode Island in August, 2007. Since 1993, presented approximately 70 papers at AAV meetings, both national and regional, on a wide range of subjects, including nutrition, critical illness, anatomy and physiology of various organ systems, surgical anatomy, avian wellness, feather damaging behavior, fungal diseases and their therapy, basic avian clinical techniques and procedures, dermatology, metal toxicoses, alternative medicine, emergency medicine, supportive care, and anesthesia.Served as a manuscript reviewer for the annual AAV Conference Proceedings.Presentations elsewhere: Presented at the American Veterinary Medical Association’s Conference, the Midwest Veterinary Conference, the American Board of Veterinary Practitioners, the European College of Avian Medicine and Surgery, Western States Veterinary Conference, North American Veterinary Conference, and the United States Department of Agriculture, as well as to vet schools in the United States including Puerto Rico, and Europe.Also presented to bird clubs, wildlife rehabbers, a national pet store chain, and the national SCAVMA convention.Books, Chapters, and Journal Articles: Co-authored two books—Avian Surgical Anatomy: Thoracic and Pelvic Limbs and Manual of Avian Medicine, and contributed book chapters to others. Published 35 papers in peer-reviewed publications, including Vet Clinics of North America: Exotic Animal Practice, the Journal of Avian Medicine and Surgery, Journal of Zoo and Wildlife Medicine, Seminars in Avian and Exotic Pet Medicine, Compendium of Continuing Education, Journal of Chromatography B, Avian Diseases, Journal of Small Exotic Animal Medicine, Journal of the Association of Avian Veterinarians, and Acta Diabetologica Latina.Served as Scientific Editor for the Journal of Avian Medicine and Surgery (2001-2002) and currently serve on the editorial review board for the Journal of Exotic Pet Medicine. Also served on the editorial review board for the journal Seminars in Avian and Exotic Pet Medicine and as a reviewer for Zoo Biology and the Journal of Avian Medicine and Surgery.Other Recent Activities and Outreach: Opened a stand-alone practice, providing more effective service to this region’s avian and exotic animal population. From 1999 to 2006, worked as an avian and exotic animal clinician at several small animal hospitals and as a consultant for the Lafeber Company. In 2005, served as the only veterinarian on the high-visibility task-force convened by the Lucas County Commissioners to address animal care and other concerns regarding the Toledo Zoo. Wrote lay-language articles for the regional Pet Lovers News, and in 2005, an article with Dr. Kirk Klasing on “Healthy Macaws” appeared in Bird Talk. Every Monday morning serves as a guest speaker on a local talk show about birds, exotic animals, and wildlife issues. Served as Chair of the Toledo Szeged Committee, the city and county diplomatic link with officials of Szeged and Csongrad Counties, Hungary.