Bad Beaks Textscottemcdonald.com/pdfs/Bad Beaks.pdf · BAD BEAKS A PICTORIAL Key Point: No matter...
14
BAD BEAKS A PICTORIAL Key Point: No matter how deformed or overgrown a beak appears, it almost never prevents a bird from eating. Introduction The beak includes the bones of the upper and lower jaws and their keratinized sheaths or rhamphotheca. This horny covering functionally replaces the lips and teeth. There is tremendous variation in the shape of the beak depending on how different species feed and live. In psittacines, the upper beak is massive and curved, whereas the lower beak is small and horse‐shaped. This is why parrots are called hook bills. A parrot’s beak is adapted to cracking large nuts and seeds as well as tearing and shredding wood from trees to provide nest sites. It is also used for grasping, climbing, preening, and displaying. It can be a formidable weapon yet also function as a delicate utensil for feeding newborn chicks. Microscopically, the horny beak resembles skin, consisting of dermis and a modified epidermis. The epidermis is very thick and its cells contain free calcium phosphate and hydroxyapatite crystals, in addition to abundant keratin. This is what helps make the beak so hard. Keratin is an insoluble protein and is the principal constituent of the epidermis in hair, nails, and the beak. The outer layers of the beak are continuously being replaced by normal wear and tear. Many bird owners erroneously believe that the upper beak grows from the cere and continues to the tip (or edges) where it is then worn off (likewise with the lower beak). On the contrary, beak tissue grows continuously outward (towards the surface) over much of the beak. As the keratinized epithelium reaches the surface, it is either worn off or may move distally a short distance before it is lost. Only towards the edges and tip does the beak tissue truly move rostrally. The surface of the beak in juvenile parrots is smooth because the growth is new. However, as the bird reaches its first year and older, the beak takes on a more irregular appearance. This is a result of the normal wearing off of the outer keratin layers. Sometimes these layers flake off or peel, leaving behind ledges
Transcript of Bad Beaks Textscottemcdonald.com/pdfs/Bad Beaks.pdf · BAD BEAKS A PICTORIAL Key Point: No matter...
BADBEAKSAPICTORIALKeyPoint:Nomatterhowdeformedorovergrownabeakappears,italmostneverpreventsabirdfromeating.IntroductionThebeakincludesthebonesoftheupperandlowerjawsandtheirkeratinizedsheathsorrhamphotheca.Thishornycoveringfunctionallyreplacesthelipsandteeth.Thereistremendousvariationintheshapeofthebeakdependingonhowdifferentspeciesfeedandlive.Inpsittacines,theupperbeakismassiveandcurved,whereasthelowerbeakissmallandhorse‐shaped.Thisiswhyparrotsarecalledhookbills.Aparrot’sbeakisadaptedtocrackinglargenutsandseedsaswellastearingandshreddingwoodfromtreestoprovidenestsites.Itisalsousedforgrasping,climbing,preening,anddisplaying.Itcanbeaformidableweaponyetalsofunctionasadelicateutensilforfeedingnewbornchicks.Microscopically,thehornybeakresemblesskin,consistingofdermisandamodifiedepidermis.Theepidermisisverythickanditscellscontainfreecalciumphosphateandhydroxyapatitecrystals,inadditiontoabundantkeratin.Thisiswhathelpsmakethebeaksohard.Keratinisaninsolubleproteinandistheprincipalconstituentoftheepidermisinhair,nails,andthebeak.Theouterlayersofthebeakarecontinuouslybeingreplacedbynormalwearandtear.Manybirdownerserroneouslybelievethattheupperbeakgrowsfromthecereandcontinuestothetip(oredges)whereitisthenwornoff(likewisewiththelowerbeak).Onthecontrary,beaktissuegrowscontinuouslyoutward(towardsthesurface)overmuchofthebeak.Asthekeratinizedepitheliumreachesthesurface,itiseitherwornofformaymovedistallyashortdistancebeforeitislost.Onlytowardstheedgesandtipdoesthebeaktissuetrulymoverostrally.Thesurfaceofthebeakinjuvenileparrotsissmoothbecausethegrowthisnew.However,asthebirdreachesitsfirstyearandolder,thebeaktakesonamoreirregularappearance.Thisisaresultofthenormalwearingoffoftheouterkeratinlayers.Sometimestheselayersflakeofforpeel,leavingbehindledges
onthebeak’ssurface.Theseledgesarewhatmakethebeaklookroughandscaly.Theseledgescanalsobemisinterpretedascracks,whichtheyarenot.Howirregularabird’sbeakappearscanalsoberelatedtodiet.AdietlowinvitaminA(seedslackVitaminA)canleadtohyperkeratosis,whichclinicallycausesthebeaktobecomethickenedandovergrown.Suchbeakscanappearveryscaly.Thebeakcanalsoappearroughifthebirddoesnotadequatelyrubitonhardinanimateobjects,suchasalavastoneorconcreteandsandperches.Partofthephysicalexaminationofeachbirdincludesanevaluationofthebeak.Mosthealthyparrotshavebeaksinwhichthesurfaceisslightlyirregularandthetipabitlong.Suchbirdsoftenreceivea“cosmetic”beaktrim.Acosmetictrimisnotnecessaryforthehealthofthebird,butbydoingso,thebirdlooksbetter,whichinturnmakestheclientmoreappreciative.Somebirdshaveapathologicconditionwhichcanchangethenormaloutwardappearanceofthebeakandaffectsomebeakfunctions.Insuchcases“corrective”beaktrimmingisnecessary.Asidefromlosingtheentireupperorlowerbeakduetotraumaticinjury,overgrowthordeformityofthebeakrarelyaffectsabird’sabilitytoeat.Beaktrimmingisaccomplishingusingavarietyoftools,includinghumannailtrimmers,cuticlecutters,andahobbytool(Dremel).Thepreferreddremeltooliselectricandvariablespeed.Acourseconicalgrindingstone(#952)istheonlybitthisauthorusesnomatterthesizeofthepatient.Dremeltoolsandaccessorystonesareinexpensive($69and$3)andcanbepurchasedatWal‐Mart,HomeDepot,Lowe’s,andmostotherhardwarestores.Anesthesia(isofluranegas)isnotrequiredforbeaktrimming,butitsuremakesiteasierandlessstressful,bothfortheveterinarianandhisassistant,andforthebird.Oneshouldbeawarethatfullyawakebirdscanstresseasilyduringthisprocedure,especiallywhenusingadremeltool,anddeathshavebeenreported.Birdsareusuallyheldinatowel.Oneshouldalsobeverycarefulnottocompressthebirdtootightlywhichcanadverselyaffectbreathingandheartrate.Thefollowingphotographsshowvividexamplesofnormalandabnormalbeaksthatwereseenbytheauthor.
Figs1and2:Trimmingabird’sbeakduringaroutineexamination.Facemasksareworntopreventinhalationofbeakdust.Thebird’sbodyisheldwithatowelbyanassistant.Thevetsecurestheheadwithonehandandwiththeother,holdsadremeltoolwhichisusedtosmoothoutthebeaksurfaceandedges.
Figs3and4:Blue‐crownedconureshowingatypical“cosmetic”beaktrim.Inthefirstpicture,thebeaksurfaceappearsalittleroughandscalyandthetipsareabitlong.Aftertrimmingthesurfaceissmoothandtheedgescleanedupandshortened.Thebeakappearsshinnyduetotheapplicationofmineraloil.
Fig5:HYPERKERATOSISRed‐headedAmazonparrot.25+yearsoldandfedadietofseedsonly.HyperkeratosisduetolowvitaminAhascausedthickeningoftheupperbeak.Noticethetwobeaklayerstowardsthetip…theinnerlayeristhenormalone.Yellowfeathersonheadareabnormalduetomalnutrition.
Fig6and7:Red‐headedAmazonparrotwithsevereovergrowthoftheupperbeak,beforeandaftertrimming.Birdfedseeddietonly.Birdwasstillabletoeat.Noticethatthelowerbeakisnormal.Seedsarehulledusingthefrontofthelowerbeakedgeagainsttheundersideoftheupperbeak.
Fig8and9:ExamplesofbeakhyperkeratosisduetomalnutritionrelatedtoFattyLiverDiseaseinaQuakerparakeetandBlueandGoldmacaw.Bothbirdswereoverweight.Themacaw’sbeakhasbecomenecrotic.
Fig10and11:SeverebeakhyperkeratosiswithnecrosisinaSeveremacawthatwasgrosslyoverweight.Noticefattytumorsinabdominalregionofthisobesebird.
Fig12and13:TwootherexamplesofseverehyperkeratosisinaBlue‐frontedAmazonandaDoubleYellow‐headedAmazonparrot.TheYellow‐headedparrotalsohaskeratinizationontheundersideofthetongue.ThisconditionisknownasWoodyTongue.
Fig14and15:TRAUMATOTHEBEAK.Babybirdsarepronetomutilationbytheirparents.If1/3ofthebeakorlessisremoved,thebeakwillgrowbacknormally.Ifmorethan1/3ofthebeakislost,itmaylooklikethisAmazonparrot.Mateaggressioncanoccurinbreedingpairs,especiallyCockatoos.ThisfemaleUmbrellacockatoo’sbeakwasseverelydamagedbythemale.
Fig16and17:AmutilatedBlueandGoldmacaw(byparentbirdswhenthisbirdwasababy)hasresultedisaseverelydistortedscissorbeak.ThebirdmaylookUGLY,butiteatsfine…infactsheisfat!Healed,damagedupperbeakandcereinaMitredconureasaresultofanencounterwithanother,largerbird.
Fig18and19:Splitlowerbeak(rightonthemidline)inaBlue‐frontedAmazon.Thetwofreelymovablepiecescannotbereattached.Surprisinglythiscausesnoproblemwitheating.AWhite‐eyedconurewithasplitlowerbeakontheleftside.Rightlowerbeaksectionhaselongatedandrisentoalevelabovethecere.
Fig20and21:Green‐cheekedconurewho’supperbeakwascompletelybittenoffbyacockatoo.Ifthisbirdwasaseedeater,itwouldprobablynotadapttoapelleteddietintimetosurvive.Fortunatelythisbirdwasapelleteaterandhassurvivedformorethan1year.Quakerparakeetshowingpermanentscarringfromapreviousinjurynearthecere.
Fig22and23INDENTATIONOFTHELOWERBEAKinAfricanGreys.ThecauseofthisconditionwhichdevelopsinsomeadultCAG’sisunknown.Thelowerbeakelongates,whichinturncausestheupperbeaktogrowouttoreachovertheendofthelowerbeak.Aftertrimming,theindentationisclearlyvisible.
Fig24and25:SCISSORBEAKisaconditionwheretheupperbeakisbenttoonesideresultinginovergrowthofthelowerbeakontheotherside.Causesmayincludeheredity,incubationproblems,malnutrition,infection,andtrauma.Incorrectfeedingtechniquesinbabybirdshavealsobeenincriminated.
Fig26and27:SeverelyovergrownscissorbeakinaMoluccancockatoobeforeandaftertrimming.
Fig28and29:VerybadscissorbeakinaBlue‐crownedAmazonparrotbeforeandaftertrimming.Thetipofthelowerbeakwasjusttouchingtheskinoftheneck.Thiswasabreederbird…shewashavingnodifficultyeating.
Fig30and31:Grotesquescissorbeakinalovebirdsecondarytoupperrespiratoryinfectiononthebird’sleftside.Afterthescabisremoved,anerodednasalandsinuscavityremains.Activeinfectionisinremission.
Fig32and33:CRACKSinthefrontofthelowerbeakarenotuncommon,especiallyinMini‐macawsandJardines.Theyrarelyextendmorethan½inchdownwardandwillnevercausethelowerbeaktosplitinhalf.Theycanbemostlygroundoutwithadremelbyshorteningthefrontedgeofthelowerbeak.Amazonparrotwithabizarre,chronicpartiallysplitlowerbeak.
Fig34and35:INFECTIONBeakrotsecondarytoPsittacineBeakandFeatherDisease(PBFD)virusinaseverelyaffectedCockatoo.Bacterialinfection(abscess)inthenasalcavityextendingintotheupperbeakcausingswellinganddisease.
Fig36and37:CANCERSquamouscellcarcinomainvolvingthelowerbeakleadingtoovergrownoftheupperbeak.Theendoftheupperbeakhadpuncturedthroughtheskinoftheneck.Thisbirdwaseuthanized.Smallbenignskintumoroccurringatthecommissureofthebeakthatwaseasilyremoved.
Fig38and39:MANDIBULARPROGNATHISM.Acongenitalbeakdeformityoccasionallyseeninchicks,especiallycockatoos,inwhichtheupperbeakgrowsdownward,insidethelowerbeak.Correctivetrimming,applyingtractionortapesplintstostretchouttheupperbeak,anddentalacrylicprosthesesarealltreatmenttechniquesthatmaybeused.Correctivetrimmingshownhere.
Fig40and41:LOCKJAWThisGoffincockatoohasanarthriticbeakconditionwhichcausesthebonesofthejawstobecomecompletelyimmobilewhenthebeakedgescometogether.Foodgetsintothemouthonlythroughthegapeinthebeak.Trimming3xayearopensthisgapeandallowslimitedmovement.
Fig42and43:MISCELLANEOUSHarlequinmacawthatwasrescuedshowingsevereelongationoftheupperbeak.Beforeandafterpicturesofa“corrective”trim.
Fig44and45:Budgerigarinfectedwithscaly‐facemites.Notehoney‐combedencrustationsaroundeye,oncere,andedgeofbeak.Beakinvolvementcancauseseveredeformity.BlueandGoldMacawshowingsignsofallergy…pink,puffycerewithskinexcoriationaroundnaresanddriednasaldischargeonbeak.
