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Section D


An elective surgical procedure, aimed at reducing problem barking. The surgery is done by a vet, during which a small incision with a bladed or laser scalpel is made in the larynx, and some of the tissue of the vocal cords is removed. This results in a softer, muted bark, although results can vary.

Default Behavior

A default behavior is something that a dog has learned and can do without needing a verbal or gesture cue from his owner.

For example, if an owner asks her dog to sit every time they approach a closed door, the dog will eventually start to sit without the owner having to ask.  The door becomes the cue.

In heelwork, the dog is expected to sit as a default behavior any time his owner stops moving.

Defensive Aggression

Aggressive behaviors refer to a variety of different things a dog does, and different emotional states a dog might be in. Defensive aggression is usually characterized by some or more of the following:

  •  Tucked tail
  • Ears pinned back
  • Lip raised to show teeth
  • Weight shifted backwards
  • Barking or growling
  • Snapping at the air
  • Whale eye
  • Raised hackles
  • Moving towards the target whilst barking or snapping, and then immediately retreating

The dog’s primary emotional state is one of fear rather than anger; the dog wants to “get the scary thing before it gets me”.


The gradual exposure to something that scares the dog, over a prolonged period of time. The exposure is started as at low a level as possible, so that the dog does not become frightened or aggressive.  As the dog demonstrates relaxation in the presence of the trigger at that level, the level is slowly increased.

For example, fear of a specific noise can be treated with desensitization  by making a recording of the noise and playing it at a very quiet volume, so that the dog barely notices it.  The volume is increased incrementally over several sessions, each time giving the dog a chance to become fully relaxed.

Desensitization is often paired with counter-conditioning in the acronym DS/CC, because they happen at the same time in a successful behavior modification setup.

Designer Dog

Any dog that has been deliberately created from purebred dogs, at the parental level, grandparental level, or higher.  Designer dogs are often given names that reflect their mix.  For example, a cross between a chihuahua and a pug is widely referred to as a “chug”.  A chug can be the outcome of a chihuahua-pug cross, or of the mating of two chugs, or of two dogs who each have two chug parents.

Differential Reinforcement

Reinforcing one choice much more heavily than others when the dog is presented with several choices about which behavior to perform.

Dogs will always choose the behavior with the strongest history of good consequences, so choosing to reinforce one possible behavior in a situation and not others will lead the dog to perform that behavior more often than the others.

This is especially useful when one of the other possible behaviors is self-reinforcing, such as chasing a cat.

Differential Reinforcement of an Alternative Behavior

In behavior modification, DRA is used to prevent a dog from performing undesirable behaviors, by reinforcing something else the dog does in the presence of the same stimulus.

For example, a dog might elicit attention when his owner is working at her desk by pawing at her, or by sitting at her feet.  If the dog’s owner gives her dog attention when he sits at her feet, but withholds attention when he paws at her, she is differentially reinforcing the sit.  It is expected that over time, the behavior of pawing would decrease and may disappear completely, and the behavior of sitting would increase.

Differential Reinforcement of an Incompatible Behavior

In behavior modification, DRI is used to prevent a dog from performing undesirable behaviors, by reinforcing something else the dog does in the presence of the same stimulus that makes it impossible for the dog to perform the undesirable behavior.

For example, a dog jumps on guests, so the owner chooses to reinforce him for sitting whenever he sees a guest.  Sitting is incompatible with jumping up, so the dog is prevented from performing the undesired behavior.


Dogs In Need Of Space.  An organization that aims to educate people about the need to respect the different personal boundaries of other dogs.  The DINOS website offers resources for owners of dogs who need space, including a list of vets that are especially sympathetic to dogs with behavioral problems.

Disc Dog

A sport for dogs and their owners, which involves the owner throwing a flying disc like a Frisbee for their dog to catch.  Points are awarded for catches at various distances.  There is also a Freestyle Disc Dog event, where an owner can choreograph a routine of trick catches for their dog and be judged on their skill and showmanship.

Not to be confused with: training discs

Discriminative Stimulus

In operant conditioning, a stimulus that determines whether or not the response will be reinforced. A positive discriminative stimulus (S+) tells the dog that reinforcement is available. For example, an owner opening the cupboard where the dog’s food is counts as an S+. A negative discriminative stimulus tells the dog that reinforcement is not available. For example, a dog might learn that a particular man never gives him pets or treats even when he does a trick, and so chooses to spend time with other family members instead.


The opposite of habituation.  A dog can become dishabituated to a stimulus after the dog has already become habituated to that stimulus, if something happens that causes the dog to associate the stimulus with a bad experience.


For a behavior to be considered proofed, it has to be able to be performed at some distance, for a duration that the owner decides, and with some distractions.
When a dog can reliably perform a behavior on cue with the owner right next to him, the next step is often to give the cue at a very short distance away from the dog, and then gradually to increase the distance.  The amount of distance required depends on the behavior and the dog’s situation


For a behavior to be considered proofed, it has to be able to be performed at some distance, for a duration that the owner decides, and with some distractions.
When a dog can reliably perform a behavior on cue, the owner can start asking for it when there are other interesting things in the environment.  For example, from teaching the dog to lie down in a quiet room, the owner could then ask for a down with another person present, or outside.

Do As I Do

A set of dog training techniques developed by Claudia Fugazza, based on modeling.  The idea is to teach the dog to copy his owner’s movements, which can then be used to teach him new behaviors and tricks.

Dock Diving

A sport for dogs, where the dog is encouraged to jump off a platform into a pool of water.  The handler uses a toy to prompt the dog to jump.  The winning dog in each division is the one who has jumped the furthest.

Dog Sense

A book by anthrozoologist Dr John Bradshaw, which is titled “In Defense of Dogs” in the UK.  In the book, Bradshaw lays out an alternative story of how the dog came to be domesticated from its wolf ancestors, and goes into detail about the misunderstandings many people have about the way that modern-day wild wolves organize themselves in social groups.

Based on these two arguments, Bradshaw makes the case for rejecting pack theory as a framework for dog training. He also explores how traditional concepts like dominance can be replaced by more evidence-bsaed ideas like Resource Holding Potential.

Dog Trainer

Anyone who trains dogs for a living. Some dog trainers work primarily with behavior modification, others specialise in sports or teaching basic obedience for pets and their owners.

“Dog Trainer” is not a protected title, and no formal training or certification is needed to call oneself a dog trainer.  However, there are many organizations that do provide professional education for dog trainers and opportunities to earn qualifications and certifications.


A brand of goggles, designed to fit the proportions of a dog’s head.  Doggles are used to protect dogs’ eyes from UV radiation, like sunglasses for humans. They are especially recommended for dogs that often put their head out of car windows, or who suffer from diseases of the eye, which might make them more sensitive to UV.

Dogs (book)

In Dogs: A New Understanding of Canine Origin, Behavior, and Evolution, Ray and Lorna Coppinger lay out theories of how the dog came to be domesticated from its wolf ancestors, how dogs have been selected for throughout human history as working companions and as pets, and why it is that dogs are so similar in terms of their genetics, but differ so much in their physiology.

The Coppingers advance the theory that the process of domestication happened when humans began to leave rubbish heaps where they lived, which attracted wolves as scavengers.  The more tolerant, human-friendly wolves would have had better access to these food sources and come into contact with people who could then start to act on their breeding.

The book is controversial in its negative portrayal of the practice of purebred dog breeding, especially of dogs that have been bred as pets.

Dogs and Storks

A program developed to help a family prepare their dog and themselves for the arrival of a new baby.

Dominance down

The act of punishing a dog by holding him down, usually flat on the floor but sometimes on his back or side.  Similar to an alpha roll, and part of the same kind of dominance theory.  The major difference between the two is that in an alpha roll, the dog is moved onto his side or back – rolled – whilst on the ground, whereas in a dominance down the dog is not usually flipped over once he is already on the ground.  Both techniques involve forcibly holding the dog in position.

Dominance Training

Training techniques that are based in the belief that many behavior problems stem from a dog’s attempt to assert himself as alpha in the household. These techniques are designed to show the dog that the humans in the household are his leaders.  Examples include:

There is a great deal of controversy over the claim that domestic dogs adhere to a pack structure, or see their relationships in terms of dominance and submission.

Don’t Shoot The Dog

A book by Karen Pryor, in which she gives a detailed introduction to the principles of behavior modification based on positive reinforcement.

The book is intended to be an overview of principles that can be applied to animals and humans in general, rather than a list of techniques specifically for dog training.


A type of designer dog.  Any dog that has had a poodle deliberately included in their lineage is commonly referred to as a doodle.  Poodles are a popular dog to use for designer mixes because it is believed that they create “non-shedding” dogs, although this is not guaranteed.
The best-known example of a doodle, the Labradoodle, is the result of the deliberate crossing of a Labrador retriever and a Standard poodle, with the aim of creating a guide dog that did not shed.

Double Leash

(1) The practice of using two leashes on a dog, either attached to different equipment or of different lengths, is called double leashing.

(2) A leash that splits into a Y-shape, with a clip on the two ends. Sometimes called a Euro leash. Double ended leashes are usually used with harnesses that have attachment points on the front and back or with head halters, and offer enhanced control.


In dogs, drive is used to describe the will to continue with an activity or pursue a goal.  It is essential in protection sports like IPO, although can be an issue in pet dogs as high drive can lead to frustration.  In particular, dogs with high prey drive can be difficult to manage around small animals such as cats.  Drive is often confused with arousal, but drive is goal-oriented whereas arousal is not.

Duckbill Muzzle

A type of muzzle made of silicon, usually yellow and resembling a duck’s beak when placed on the dog.  Unlike basket muzzles, the dog cannot eat or drink when wearing it.


For a behavior to be considered proofed, it has to be able to be performed at some distance, for a duration that the owner decides, and with some distractions.
When a dog can reliably perform a behavior on cue, the owner can start gradually increasing the time the dog must stay in position before he is released.  How long the dog needs to be able to stay in position depends on the behavior and the needs of the owner.


Doctor of Veterinary Medicine. The title given to veterinarians in the United States and Canada.  The only exceptions are vets who have graduated from the University of Pennsylvania, who are awarded the equivalent title VMD.