Behavior is, thankfully, malleable. However, certain patient characteristics make altering a behavior easier or more difficult.
A patient's size will affect the owner's ability to control the animal and may impact the severity of an injury the animal
could inflict. Large dogs are at greater risk of euthanasia for aggression.5
That is not necessarily because larger dogs are more aggressive than smaller dogs but because larger dogs have the potential
to inflict greater damage when they do bite.
The patient's signalment will also factor into the situation—sometimes merely because of public perception. The risk of working
with notorious breeds such as pit bulls, rottweilers, Doberman pinschers, or German shepherds can be greater than with other
breeds because the public is frequently less forgiving of misbehavior by these breeds. The owner of a biting pit bull may
be more likely to be sued than the owner of a biting golden retriever. Remember also that breed predispositions for behavior
traits may influence treatment steps. For example, herding breeds often chase and nip at people and are reactive to other
Dog bite studies indicate that intact male dogs generally account for more bites than dogs of other reproductive statuses.6,7 Admittedly, this may be in part because owners of intact male dogs may be less likely to contain or train their dogs than
owners who take steps to alter their dogs.
Older animals may suffer from medical issues and brain aging that can complicate treatment steps. Serious behavioral disorders
in very young animals often indicate congenital or genetic contributions and may indicate a poorer prognosis in some situations.
Genetic and environmental influences are intricately intertwined. Research in a variety of species and a variety of fields
shows genetic expression can be altered with environmental experience8-10 ; however, the animal's genetic template is set and will influence the types of behaviors expressed as well as the approach
to resolving them. Pets that have various types of developmental or genetic disorders (e.g. deafness, impulse control disorders) often have a poorer prognosis because the rehabilitation process can be longer and more
arduous. In my experience, working with animals with such disabilities often requires a higher skill level on the part of
the owner and assistance from a more educated behavior professional.
The pet's developmental period, especially the socialization experience, is a key influence on future behavior.11-13 Certain training during this time can greatly reduce the likelihood of behavior problems; other training practices will
induce or worsen certain behavior issues. Training and puppy raising methods that emphasize "dominance theories" and confrontational
techniques damage the owner-pet relationship and can increase biting and aggressive responses toward owners.14,15 I have seen a number of dogs develop noise phobia and fear of people in direct response to the training philosophy of one
currently popular training franchise. This method involves yelling at the dog and throwing chains in the dog's direction to
startle or scare the dog into stopping the undesirable behavior.
As with people, developmental changes during an animal's juvenile and adolescent period have a notable impact on the animal's
interaction with its environment and, thus, its behavior. This period is the most trying time when raising a pet and a time
when most owners reach the limits of their knowledge and fall short of their obligations as responsible pet owners. Poorly
socialized pets may pose a greater challenge for rehabilitation.
The pet's medical history, including the diet, supplements, and medications it is receiving, is important to know because
these things will affect its behavior.16-22 Certain conditions, diets, and medications may limit the success of a program or may facilitate success. For example, gastrointestinal
disorders may complicate resolution of inappropriate elimination disorders. Dietary restrictions for animals with food allergies
can make training programs more challenging in terms of finding useful reinforcers and adequate foraging enrichment activities.