Classification of Aggression in Dogs

A. Target

  1. Family members (owners): Dominance
  2. Strangers: Fear- Dominance
  3. Dogs: Inter-dog- Fear
  4. Other animals: Predatorial - Fear - Dominance

B. Contextual

  1. When people enter or leave: Territorial - Dominance
  2. When things are taken from dog: Territorial - Dominance
  3. When dog touched or moved: Dominance
  4. When dog punished: Fear/Pain - Dominance
  5. When people run by : Predatorial

C. Motivational

  1. Dominance aggression
  2. Aggression directed toward children
  3. Territorial aggression
  4. Fear-based aggression
  5. Predatory aggression
    1. Squirrel
    2. Baby
  6. Interdog aggression
  7. Pain-elicited aggression

Description and Treatment of Aggressions

A. Dominance-related aggression

  1. Signalment
    1. Young adult (1-3 years) male purebred dogs
    2. Also sometimes seen in females and mixed breeds
    3. All breeds, but some more common:
      1. English Springer Spaniel
      2. Cocker Spaniel*
      3. Lhasa apso
      4. Poodle* (standard)
      5. Golden Retriever*

      *AKC's top breeds

    4. Cornell - 44% of dog cases are aggression
    5. Most commonly diagnosed behavior problem in dogs
  2. Dominance Aggression - Description (red-flag behaviors)
    1. Growling, snarling, snapping or biting usually directed at family members.
    2. Context of dominance hierarchy within family
    3. Wide range of manifestations: growling to multiple-bite attacks
    4. "Dr. Jekyll & Mr. Hyde"; glazed expression (dog almost does not know what was done wrong)
  3. Circumstances that illicit aggression
    1. Critical (scarce) resources defended:
      1. Food
      2. Toys/objects
      3. Resting place
      4. "Mate"; favorite person (may change)
    2. Disturbed while sleeping or resting
    3. Person approaches specific items or people
    4. Family member leaves room
    5. Response to dominant gestures or postures:
      1. Punishment or threats
      2. Petting
      3. Hugging, kissing
      4. Bending over
      5. Stepping over
      6. Pressure on shoulders or back (**very significant!)
      7. Restraint
      8. Fixed stare (in very young pups, even)
      9. Grooming, bathing
  4. General Facts
    1. Great range of presentations, varying prognoses (fair to very poor)
    2. Genetic predisposition, not owners' fault
  5. Prognosis
    1. Cannot "cure" or guarantee no more aggression.
    2. Depends on what owners willing to live with
    3. Poor px (prognosis) if babies, toddlers or infirm elderly in household
    4. Poor px if unpredictable
    5. Little better px if growler (warns)
    6. Little better px if historically slow escalation
    7. Must work on program forever
  6. Treatment
    1. Castration
    2. Owner education & counseling
    3. Avoid eliciting aggression
      1. No physical punishment because they get worse
      2. Do not disturb while sleeping/resting
      3. No rough play or contact mouth games; fetch only, no tug of war, or roughhousing
      4. No alpha rolls unless very mild aggression, small dog
        1. May physically suppress aggression but it will return
    4. Change lifestyle so that owner assumes dominance and dog assumes sub-ordinance
      1. Sit-stay program
      2. "No free petting" program
      3. Halter (Promise collar)
      4. 30 minute down
      5. Food game
    5. Keep leash on in house (+/- halter)
    6. Muzzle
    7. Desensitization to eliciting stimuli
    8. Do not allow on furniture or laps
    9. Drugs - Elavil, Paxil, Prozac - prescribed by Vet Only (70% fair prognosis helps)
    10. Do not allow jumping UP

Low protein diet


  1. Indicated if babies or elderly are at risk
  2. If owners will not tolerate even reduced risk (i.e. will always be present)
  3. Predictability
  4. Severity
  5. Multiple-bite attacks or rage
  6. Increase in occurrences

B. Idiopathic Aggression

  1. "Rage syndrome" - (non predictable - can be unattended dominance aggression)
  2. "Paradoxical rage reaction"
    1. Probably an extreme manifestation of dominance aggression
    2. Multiple bite attacks, cannot "turn off "
    3. Genetic predisposition
    4. Lack of predictability, appears "unprovoked"
    5. Historically rapid escalation
    6. Pathophysiology: neurotransmitter dysfunction (is medica!) Iower serotonin metabolites, seizure, hypoxia/ischemia


C. Aggression Directed at Children

  1. May be generally dominant-aggressive dog
  2. May be dominant-aggressive in only this context
  3. If unfamiliar with children or children rough could be fear or pain-based aggression
  4. Predatory aggression
  5. Any age, sex, or breed. (Older dogs?)
  6. Avoidance behavior: child pursues dog.
  7. 1.5 to 5 year old children; can start with crawling
  8. Treatment
    1. Generally dominant dogs: as above
    2. Muzzle - better than isolation
    3. Treat for pain (DJD - degenerative joint disease)
    4. Give dog "child-free space"
    5. Control is important- both child and dog
    6. Counter-conditioning
      1. Obedience with child giving commands, parent enforcing or hold child while adult gives command
    7. Desensitization
      1. Presence of child
      2. Approach of child
      3. Touch
      4. Behavior around food bowl, toys
    8. Limit attention to times child is present
    9. Children too young to avoid eliciting aggression — do not leave unsupervised with dog

D. Territorial Aqqression

  1. Growl, bark, bite at strange (unfamiliar) humans or animals German Shepherd, Labrador Retriever, Dalmation, Mixes & Cairn Terr.
  2. When owner or a specific area (e.g. car) is approached
  3. Signalment
    1. Young adults, 1-3 years
    2. Any breed; some breeds predictably territorial (German Shepherds)
    3. M or F; possibly worse in males
  4. Circumstances
    1. Strangers or animals passing house or yard
    2. Strangers or animals entering house or yard
    3. Strangers or animals trying to leave, or moving room to room
    4. Owner approached, even away from home
    5. In car (gas station, toll booths, etc.)
  5. Prognosis
    1. Good, unless aggression severe +/- owners non-compliant
  6. Treatment
    1. Prevention
      1. Muzzle dog
      2. Bring outdoor dog indoors
      3. Do not leave unsupervised in yard or on cable
    2. Castration—not a significant effect (note spaying makes bitches worse)
    3. Desensitization & counter-conditioning
      1. Sit-stayprogram
      2. Attention-seeking program
      3. Halter
    4. The Fisher method: remove both rewards - the flight of the target and the owners' attention
      1. Tie dog
      2. Target approaches
        1. If dog lunges, growls, barks, stiffens, owner walks away from dog target stays put
        2. When dog stops aggression owner returns, target leaves
    5. Door control program
      1. May need leash in house at all times
      2. Muzzling better than isolation
      3. May need to isolate until people have entered, then bring dog to greet
      4. May need to greet outdoors ("please toss a treat to my dog when you come in!")

E. Fear-based Aggression

  1. Signalment
    1. Male or Female
    2. No age predilection
    3. All breeds; some predisposed to fear (German Shepherd, Australian Shepherd, Golden Retriever, Border Collie- ?sensitive breeds?)
  2. Description
    1. Growl, bark, bite at animals or humans, family or strangers
    2. Posture and expression of dog fearful (or ambivalent)
    3. Can be ambiguous or vague
  3. Circumstances
    1. Veterinarian
    2. Response to punishment, pain, threat
    3. When approached, reached for — often exhibit avoidance first
  4. Treatment
    1. Identify stimuli carefully
    2. Desensitization & counter-conditioning so can't back up or lunge
    3. If reactive, no reward or punishment
    4. Do not punish
    5. Do not reassure

Drugs - not benzodiazepines (i.e. Valium if aggressive; might get worse if dominant aggressive because fear will be removed). Anti-anxiety drugs e.g. buspirone or amitriptyline (Elavil) - good choice


F. Predatory Aggression

  1. Signalment
    1. Male or Female
    2. No age predilection
    3. No breed predilection (?northern-breeds? - prick ears - tail curled over back - spitz)
    4. Not a common complaint
  2. Description
    1. Chasing and biting humans, animals, objects
    2. Not all chases are by definition predatory; latter does not involve growling, barking
    3. May start with stalking
    4. Elicited by fast moving stimuli
    5. Fatal attacks are often predatory
    6. Multiple dogs facilitate one another
    7. INFANTS*- special case (below)
  3. Treatment - Prevention
    1. Chasing: control dog (leash or fence) teach commands from distance to stop bolting; put bell on dog to warn prey—but chased animals still stressed; desensitization and counter-conditioning
    2. Severe predatory aggression
      1. Prognosis poor if uncontrolled (objective is to kill target)
      2. Serious liability
      3. Muzzle
      4. Increase food intake ad lib (KD Diet - Low Protein/High Fat)
      5. Do not have a dog with serious aggression in home with a baby/toddler!!
  4. INFANTS* -
    1. Reaction to crying or smells?
    2. Can occur in dogs "socialized" to babies
    3. Prevention:
      1. 1 ) Before arrival of baby
        1. Change dog's schedule to anticipated new schedule
        2. Provide quality time 5-10 minutes daily when baby is present
        3. Practice controlled exercise
        4. Permit familiarity with room, crib, etc.
        5. Bring home baby's soiled clothing, leave around house
    4. Introduction
      1. If possible introduce on neutral territory; if not, dog should not be present when baby enters home
      2. Hold baby - protecting head while spouse holds dog on sit-stay
      3. Gentle praise for curiosity: DO NOT DANGLE BABY
    5. Parent-baby interaction
      1. One spouse always monitoring pet
      2. When one spouse home, if necessary leash, muzzle or gate dog
      3. NEVER leave dog alone with baby, even if asleep
      4. Some dogs must be leashed even if someone home
      5. Pay attention to dog only when baby present
      6. Do obedience holding baby

G. Aggression Between Dogs in Home (Inter-Dog Aggression)

  1. Signalment
    1. Typically inter-male or inter-female—rarely between sexes
    2. No breed predilection
    3. Age: possibly young adults, vs. old adult dog
  2. Circumstances
    1. Fights can be severe and cause injury or death, esp. inter-female
    2. Involve dominance or fear
    3. Often in owner's presence: greeting, playing (competitiveness, excitement?)
    4. Doorways
    5. Critical resources
    6. Tense owners give "cues"
    7. Other dogs may be attacked outside from a distance (nonselective), outside after investigation (selective), or fights may occur between dogs in home (commonly females).
  3. Prognosis
    1. Interfemale aggression in home may be difficult to treat
  4. Treatment
    1. Castrate males
    2. Spay females if aggression associated with estrus/pregnancy/whelping (Spaying females can sometimes make situation worse, not better)
    3. Separate dogs when unsupervised
    4. Avoid circumstances that elicit aggression
      1. Downplay greetings
      2. Don't give bones/rawhide when uncontrolled
      3. Leash aggressive dog outdoors
    5. Muzzle
    6. Drugs - See your vet! .
    7. Halter (for desensitization exercises) - might not work!
    8. Desensitization and counter-conditioning

H. Aggression toward strange dog

  1. Signalment
    1. Male more than female
    2. Circumstances and motivation
      1. Territorial, dominance (personal space invaded or fear)
  2. Treatment
    1. Control - do not allow to run free, muzzle
    2. Castrate (Helps 75% of cases)
    3. Socialize
    4. Desensitize

I. Pain-elicited Aggression

  1. Signalment
    1. No age, breed or sex predilection
    2. Increased likelihood in geriatric dogs
  2. Circumstances
    1. May be related to dominance or fear
    2. Residual aggression: may anticipate pain in subsequent events (fear, dominance)
  3. Treatment
    1. Treat cause of pain
    2. Avoid eliciting pain
    3. Avoid physical punishment
    4. Desensitization and counter-conditioning

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