The early psychological development of puppies is of concern to the veterinary profession because inadequate socialization and habituation can result in behavior problems related to fear and some types of aggression, the consequences of which can compromise the welfare of the animals in their care.
Definition of socialization and habituation
Socialization
The process whereby an animal learns how to recognize and interact with the species with which it cohabits.
Socialization is normally limited to the animal's own species in the wild but for the domestic dog it includes other species with which it cohabits, such as human and feline.
Learning that these, in all their variations of appearance and behavior, are normal reduces the potential for the development of fear and aggression motivated by fear .
Through interaction the socialized dog develops communication skills that enable it to convey intention and recognize and how to respond to the intentions of others.
Habituation
The process whereby an animal becomes accustomed to benign environmental stimuli and learns to ignore them.
Development
The sensitive period
During the sensitive period experiences have a greater effect on the development of canine temperament and behavior than those that occur in later life.
The timing of the sensitive period is genetically determined but environmental factors can cause it to vary.
Its start is contiguous with maturation of the nervous system and the onset of full sensory perception and mobility at 2½-3 weeks and lasts until 12 to 14 weeks.
During the sensitive period puppies are at their most able to accept the presence of novel stimuli but after five weeks an unwillingness to approach starts to develop.
Exposure to a broad range of benign stimuli in this period is important for the realization of the puppy's genetic potential for confident behavior.
Obtaining puppies from domestic environments, rather than environments with less stimulation, such as barns, isolated rooms and kennels, prior to eight weeks of age and exposing them to busy urban environments before the end of the socialization period is indicated as the best procedure for avoiding problem behaviors related to fearfulness and aggression towards people.
The absence of experience and social referencing can result in abnormal behavior and the development of behavior problems in later life.
Puppies raised in a non-domestic maternal environment are more likely to be referred to a behavior counsellor for aggression towards veterinary surgeons than puppies that experience a domestic maternal environment.
Although the sensitive period is important for the development of confidence ongoing exposure to a broad range of benign stimuli until social maturity is also necessary to prevent the development of fearful behavior.
The breeder should provide the right environment for puppies to reach their potential for the development of confidence.
Breeders should ensure exposure to a wide range of normal environmental stimuli.
Research and experience suggest that a domestic maternal environment is preferable to the stimulus deprivation normally associated with barns, sheds, kennels and similar locations.
A puppy that has had regular experience of a television, vacuum cleaner, etc will be more able to cope with stimuli beyond the breeder's environment than one that has been shut away in a quiet kennel or room.
Audiotapes, CD and video recordings of stimuli that occur outside the domestic environment can be made and played. These are especially helpful if an older puppy is unwell or for some other reason there is a delay in taking it beyond the maternal environment or the first owner's home.
From the earliest possible age puppies should be handled so that they become acclimatized to gentle human contact and human bodily odors.
As the puppy grows the breeder should increase the amount of interaction it has with them and other people. Ideally this should include experience of people of all age groups and both genders.
Advice regarding hygiene and infection control procedures should be given to breeders.
Breeders share responsibility for ensuring that new owners are aware of the importance of socialization and habituation after the puppy has left the maternal environment and how they can achieve it.
Age of homing
Homing puppies before 8 weeks of age is the best procedure for avoiding problem behaviors related to fearfulness and aggression towards people.
However, the Breeding and Sale of Dogs Act currently does not permit the sale of puppies by breeders to the general public until puppies have reached 8 weeks of age.
The field experience of Guide Dogs for the Blind has found an optimum age is 6 weeks in the breeds used for that work.
There is some evidence that puppies may be particularly sensitive to environmental challenge at 8 weeks of age.
Insufficient exposure to stimulation in the maternal environment increases the need for early homing.
For early homing to be beneficial the environment the puppy is homed to must provide the ongoing stimulation necessary for the development of confidence.
There is a dichotomy between the need to broaden a puppy's range of early experience so that it has the best chance of developing a sound temperament, and the need to ensure its safety until its vaccination program is complete. Early vaccination programs can help overcome this.
It is the responsibility of the veterinary surgeon to use his or her knowledge and expertise to advise clients of the actual local disease risk, which may be higher or lower than national averages.
The actual local disease risk should be used to determine vaccination and socialization policy and methods.
The owner's role prior to completion of vaccination within the home
Visitors
Owners should accustom their puppy to visitors of both sexes genderand all ages. For complete socialization visitors should be of various age, appearance and race. This will develop its social experience, reducing the potential for fear and aggression towards strangers and visitors to the home in later life.
Children
All puppies should be accustomed to being handled by the owners' and/or other people's children but should ensure that they are supervised to ensure that the puppy is not overwhelmed, stressed or caused to learn to associate children with over-excitement and boisterous behavior.
Babies and toddlers
All puppies should be accustomed to the sight and sound of babies. This can be especially important if the owners or their relatives plan to have a family.
Many puppy owners do not have small children, but audio recordings are very useful for habituating a pup to the noise of children.
Grooming
Owners should groom their puppy every day to accustom it to this procedure and to being handled.
Grooming training should begin with gentle grooming equipment that does not hurt or irritate the puppy's skin.
Examination
Owners should be encouraged to frequently simulate external examination. Once it is evident that the puppy has learnt to enjoy the procedure they should ask other people to conduct the procedures. Developing pleasant associations with this activity reduces the potential for stress and defensive behavior during actual examination.
Examination should include all body areas; eyes, ears, mouth, feet, tail, etc.
Care must be taken not to allow this examination to turn into a play-fight.
Coercion and punishment must not be used.
Domestic sights and sounds
Systematic exposure to domestic stimuli should continue. If not started by the breeder the puppy should be accustomed to them gradually without being stressed.
Delivery people.
As long as the puppy does not show apprehension of strangers, puppies should meet these people at the threshold of the property as often as possible so as to reduce the potential for the development of excessive territorial behavior towards this at-risk group. Greater effect will be achieved if people who deliver things can be encouraged to feed titbits.
Other dogs at home
Once a resident dog has made the initial acceptance, the two should find their own level and settle down without too much intervention from the owner.
Old or physically debilitated animals must be supported and not allowed to be bullied and intimidated by a new puppy. They should not be treated as 'puppy-minders'.
Cats
The puppy should be kept under control and rewarded for not pestering the cat.
Introductory sessions where the cat is placed in a cat-carrier, in view but out of the puppy's reach, or the puppy is placed in an indoor kennel can be a useful method of introduction because for a reduced risk of a chase/flight association developing. In this situation the cat carrier must be partially shrouded and there must be a box or similar barrier for the cat to hide behind should it feel threatened.
Introductions should be repeated at intervals for a few days so that both puppy and cat learn to settle in each other's company.
Conditioning to accept isolation from social contact
Puppies that are unaccustomed to being left unattended may display problem behavior when separated from their owners latter in life due to over-dependence or frustration because their expectations are not met .
The puppy should regularly be left alone for periods of time, preferably in the area that it sleeps in overnight if it settles.
These periods of solitude should be frequent [several times each day] but brief at first [only a few minutes], with the time alone being extended as the puppy copes without distress.
To prevent the puppy from chewing inappropriate items etc the area must be "chew-proof" and free from hazards such as electric cables. Owners may need to use an indoor kennel, construct or buy some purpose-built barriers to make a pen or use a child gate to keep the puppy in a chew-proof area or room.
The puppy should be left with appropriate items to chew and rip up, together with activity feeders and fresh water.
Extending the period of owner absence
Initially the owner should accustom the puppy to separation by sitting in the same room whilst it is in a pen or indoor kennel, or the next room if they are using a child gate.
The period of separation and the extent to which the puppy is isolated can be built up until the owner can sit in another room with the door shut.
The puppy can then be accustomed to periods of owner absence from the home. These should be gradually extended.
The best time to conduct training is when the puppy appears to need rest.
The owner should return when the puppy is quiet and relaxed, thus avoiding accidental reinforcement of distress or relocation/attention seeking vocalization.
Progress should be at a rate consistent with the development of the puppy's capacity to cope with social isolation.
Conflict between the puppy's psychological development and the need for immunization
The combination of the age at which a puppy is obtained and the time taken for the completion of the vaccination program can result in the puppy being retained in the new owner's home until after the sensitive period has finished.
A vaccination program that provides early cover and/or early completion will reduce the risk of inadequate experience during this period.
Regardless of the vaccination regime the absolute necessity for proper socialization demands that the actual risk of disease be balanced with the need for proper behavioral development.
Carrying the puppy away from home before the completion of vaccination programme
Clinical judgement should be made as to whether the owner is advised to carry their puppy away from home to broaden its experience prior to the completion of the vaccination program.
Puppies should be taken to as many environments as possible to give them wide experience.
Expose to the sound of traffic and the movement of people.
Take to locations where people congregate so that the puppy experiences interaction with strangers.
Expose to a variety of children. Start with single children and increase the number gradually.
Accustom to car travel and to traveling in the location it will occupy when it is an adult.
Accustom to the countryside, livestock etc.
If it is intended to use boarding kennels the puppy can be familiarized with the environment when it is older, eg by occasional day boarding.
Socializing with other dogs
Steps have to be taken to ensure that the process of learning to interact with other dogs continues if maladjustment is to be avoided.
Adult dogs met at random may be incompetent communicators and cause inappropriate interaction to be learnt.
Owners should be encouraged to attend socialization classes with their puppy.
Benefits of puppy parties and puppy classes
Puppy parties
Puppy parties, a one off event or a series of classes, are typically run by members of staff and held within the veterinary practice out of hours.
Holding as a one off event may mean that there is too much information for the owners at one time and reduces the socialization opportunities. A rolling program of puppy classes that puppies can join as soon as they are old enough addresses these issues.
Puppy socialization classes
Similar to puppy classes, often run by local dog training clubs. Useful to refer clients on to especially if not providing a service or only puppy parties within practice. Clients may also go on to develop their dog's training further.
Requirements
At the practice
Puppies with no signs of illness can attend 7 days after first vaccination and clinical check.
Waiting room should be cleaned with an appropriate agent to minimize the risk of disease transmission, eg Virkon.
Puppies should be segregated from adult animals by using an alternative entrance.
Avoid giving second vaccination on same day as class; the combination of stresses may be too much.
Ideal number 4-8.
At a dog training club
All puppies should have completed vaccinations.
Only puppies should be in attendance. The behavior of some adult dogs may be detrimental to the learning desired.
Benefits
Social contact with other puppies of a variety of breeds and a variety of people. All family members are encouraged to attend, including children who will have to be kept entertained.
Socialization can be expended in class by dressing people up in types of clothing puppies may encounter, eg hats, walking sticks, flapping coats.
Opportunity to discuss wider socialization strategy.
Pleasant associations are formed with the veterinary practice, inhibiting the effect of associations with unpleasant events that may occur in later life.
An opportunity to develop a client bond with the practice and to promote aspects of healthcare.
Opportunity to broaden client education and develop their training skills.
Prevent causing fear through excessive challenge
To avoid the development of fear puppies should be initially introduced to experiences at a low level of stimulation, which can be increased provided they remain relaxed. For example, exposure to urban settings can start in quieter side streets or at quieter times.
Owner response to fear
Owners must be aware of the signs of apprehension so that they do not inadvertently ignore signs that a puppy is not overexposed to a situation it is frightened of.
Reassurance may reinforce fear and should be avoided.
Owners should avoid trying to pressure a puppy into approaching a stimulus it is fearful of.
Stimuli that worry the puppy should be minimized by increasing the distance at the time of exposure or reducing the salience of the stimulus so that the puppy can become habituated or desensitized to it. As the puppy's response improves the level of exposure can be increased.
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Other sources of information
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Freeman D (1991) Barking up the Right Tree. Ringpress Books. Letchworth, Herts, UK.
Bateson P (1981) Control of sensitivity to the environment during development. In: Behavioural Development.Ed. K Immelmann, G W Barlow, L Petrovich & M Main. Cambridge University Press. pp 432-453.
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Vetstream contributor(s)
David Appleby MSc, The Pet Behaviour Centre, Upper Street, Defford, Worcestshire WR8 9AB, UK.
Jon Bowen BVetMed MRCVS DipAS(CABC), 42 Hove Street, Hove, East Sussex BN3 2DH, UK.
Organisations
The Association of Pet Behaviour Counsellors, PO Box 46, Worcester WR8 9YS, UK. Tel/Fax: +44 (0) 1386 751151; E-mail: apbc@petbcent.demon.co.uk ; Website: www.apbc.org.uk
