Introduction
Canine behaviour problems are common. In the USA, 87% of veterinary clients stated that their dog had a behaviour problem (Campbell, 1986) as did 65% of dog owners in Melbourne (Kobelt, 2004). Beaver (1994) found aggression (territorial, owner protection) was the most common problem followed by barking, chewing, digging, food begging, house soiling, jumping on furniture/people, running away, fear especially of noise, disobedience, hyperactivity/excitement, timidity, stealing food, destructive behaviour, and eating faeces. Behaviour problems in dogs can be classified as normal or abnormal behaviour. They may be a management, training, or fear/anxiety based. The behaviour may be a problem for the dog's owners, their neighbours or society as a whole. Most small animal behaviour specialists categorise canine behaviour problems as aggression, elimination disorders, fear/anxieties, stereotypes, and miscellaneous (destructive, unruly, mounting, hyperactivity, barking, chasing etc) (Overall, 1997; Landsberg, et al., 2003).
Two fundamental tenets of animal welfare are 1) that an animal should be free to engage in normal behaviours, and 2) that an animal should be free of fear and anxiety. If normal behaviour is defined as the behaviour of the progenitor species or feral conspecifics, then few dogs express their full repertoire of behaviours. Indeed dogs are not allowed, by law, to exhibit many normal behaviours. Anxiety and fear based problems are important in relation to the welfare of the dog because they indicate an unpleasant state of existence. Pathological behaviours, such as stereotypical behaviours reflect an abnormal mental state and dogs engaging in such behaviours are or have suffered some form of distress.
The welfare significance of any behaviour problem will be determined 1) indirectly by how it affects the dog's owner and how this impacts on the dog's life, and 2) directly by how the underlying emotional state (e.g., anxiety) affects the animal itself.
Owner Response
Many normal dog behaviours are unacceptable to humans. If allowed to roam, dogs scavenge, defaecate freely, bark, are sexually promiscuous and are predatory. Restraining dogs limits their ability to express these normal behaviours. Dog owners' legal and social responsibilities encourage them to restrict their dog and this may lead to anxiety-based abnormal behaviours. The behaviour of a dog may cause it to be managed in a way that affects its welfare; normal but unacceptable behaviour (e.g., barking) may result in the dog being abused, ignored, given away or killed. Behavioural problems may cause the human-dog relationship to deteriorate, increase the likelihood of the dog being abused or killed, affect the social milieu in which dog lives, and make it more difficult for the dog's owner and the owners of other dogs to exercise their dogs off the leash.
Although there is no data to support it, the contention that dogs which are difficult to control and aggressive either towards other dogs or people are less likely to be walked frequently and allowed off leash is self-evident. Dogs that are territorially aggressive may be caged or chained for human protection and may not have much social contact. Dominantly aggressive dogs may be kept away from family members. Dogs that jump up on people may be kept away from people with a subsequent reduction in play and exercise. Digging dogs may be kenneled or chained to protect the garden. In each case the owner's response results in reduced activity and social interaction for the dog, i.e., poorer welfare.
When owners attempt to retrain their dog, punishment is often used ineffectually, resulting in the dog becoming fearful of its owner or being injured physically. Remote punishers like anti-barking collars cause specific problems (Stafford, 2008) and training tools like choke chains are painful in untrained hands. A failure to eliminate the behaviour problem may result in the dog being relinquished to a shelter or being destroyed.
Direct Effect of a Behaviour Problems on the Dog's Welfare
Many behaviour problems are expressions of chronic fear and anxiety. Fear determines the response to a dangerous stimulus. It is by definition unpleasant and may be acute or chronic. Fear becomes a welfare issue when the response to non-dangerous stimuli is excessive, or when the owner's response is inappropriate (e.g., punishing submission urination). If fear occurs frequently, becomes chronic or leads to phobia or anxiety, then it is a welfare problem for the affected animal. An acute fearful response is not significant as it is usually brief. Phobias are excessive fears disproportionate to the circumstance that causes them (McCobb, et al., 2001). If a dog responds in an excessively fearful manner to a common and non-dangerous stimulus then its welfare may be compromised. People, noise and places may evoke extreme fearful responses. A dog may injure itself as it tries to escape. In one survey, 40% of dogs suffering from thunderstorm phobia were under one year of age when they first showed signs such as shaking, salivation, loss of bladder and bowel control. Many sought humans, became destructive, vocalised, self-mutilated or hid, all indicators of poor welfare (McCobb, et al., 2001; Crowell-Davis, et al., 2003).
Anxiety is the apprehensive anticipation of future danger (Overall, 1997). Separation anxiety is associated with separation from a preferred companion. It is chronic anxiety and impacts negatively on the affected dog. In North America it is diagnosed in 20-40% of dogs referred to animal behavioural practices (Voith and Borchelt, 1996; Simpson, 2000), and 14% of dogs presented at veterinary clinics show signs of it (Overall, et al., 2001). The common signs of separation anxiety are destruction, excessive vocalisation, inappropriate elimination or self mutilation when the preferred person leaves the dog.
The cause of compulsive disorders or stereotypic behaviours (Luescher, et al., 1991; Landsberg, et al., 1997; Overall, 1997; Luescher, 2003) in dogs is poorly defined but genotype, experience, medical problems, conditioning and stress caused by inadequate environmental conditions have all been considered important. Acral lick granulomas are most commonly seen after an injury to a leg. It is thought by some that conflict behaviours caused by environmentally-induced stress are important in the aetiology of compulsive disorders (Luescher, 2003) however, specific environmental causes of compulsive disorders have not been identified. Compulsive disorders are indicative of poor welfare, both in their aetiology and in the fact that they may interfere with normal behaviour and be self-destructive. The prognosis for complete recovery is influenced by the duration of the problem, but lifelong drug therapy is not uncommon (Overall, 1997; Luescher, 2003). The degree to which the welfare of individual animals with a compulsive disorder is compromised is unknown and will presumably be influenced by the developmental stage of the disorder and the type of disorder. Individual dogs may be stressed while engaging in the behaviour but for others it may be a coping mechanism (Duncan, et al., 1993), to deal with an inadequate environment. The existence of a compulsive disorder suggests that the environment in which the dog lived was inadequate and that its welfare was compromised at some time. The proportion of dogs with compulsive disorders is unknown and difficult to estimate but it is probably under-diagnosed.
Aggression in dogs has been classified as fear, dominance, territorial, play, protective, idiopathic, possessive, redirected, food-related, inter-dog, maternal and predatory (Overall, 1997). In all forms of aggression, the dog or dogs involved can be injured. Aggression is significant for the welfare of dogs in that it may result in dogs being killed (Reisner, et al., 1994; Galac & Knol, 1997) rather than treated. In one German state during 1990, 34 dogs were shot by police after the dogs endangered, injured or 'lethally injured humans' (Roll & Unshelm, 1997). In addition, the public perception that dog attacks are a significant public health problem influences politicians, whose response is to make dog control more strenuous. Legislation that dogs have to be on a leash at all times in public places and never allowed to run free impacts on the welfare of dogs. Many forms of aggression are protective and may not be significant welfare-wise in that they are temporary. However, some forms of dominance aggression may be caused by anxiety in the dog about its position in the family (Overall, 1997). This type of aggression is likely to have long-term effects on the dog's well-being. Canine victims of dog attacks may become fearful and aggressive towards all dogs or dogs of a particular type. Most forms of dog-to-dog aggression are normal, but unacceptable. These forms of aggression by themselves may not be a particularly significant factor in the welfare of either dog involved, as it is normal behaviour and injuries are usually moderate rather than severe, but the response of humans to such aggression may cause significant restriction in the lifestyle of either the aggressor or victim, and this may have a more significant impact on the dog's welfare than the aggression itself.
Conclusions
Behaviour problems may impact on a dog's welfare directly (anxiety based problems) or indirectly through the owners' response to the behaviour. Normal dog behaviour (e.g., barking, wandering) may be unacceptable to its owner and/or society and may result in the dog being isolated, killed or punished. Such normal behaviours are unlikely to be damaging to the dog directly. However restrictions which inhibit normal behaviour may result in the development of abnormal behaviours. Anxiety and fear based behaviours (e.g., separation anxiety, thunderstorm phobias) are by definition unpleasant experiences and have negative impacts on the affected dogs' welfare. Stereotypic or obsessive compulsive behaviours suggest that the dog has lived or lives in an inadequate environment. Managing dogs to maximise their ability to behave normally and to minimise behaviour problems, particularly anxiety and fear based problems, will impact positively on their welfare.
References
1. Beaver BV. 1994. Owner complaints about canine behaviour. Journal of the American Veterinary Medical Association 204, 1953-5.
2. Campbell WE. 1986b. The prevalence of behavioural problems in American dogs. Modern Veterinary Practice 67, 28-31.
3. Crowell-Davis SL, Seibert LM, Sung W, Parthasarathy V, Curtis TM. 2003. Use of clomipramine, alprazolam and behaviour modification for treatment of storm phobia in dogs. Journal of the American Veterinary Medical Association 222, 744-8.
4. Duncan IJH, Rushen J, Lawrence AB. 1993. Conclusions and implications for animal welfare. In Stereotypic Animal Behaviour: Fundamentals and Applications to Welfare, edited by A.B. Lawrence. CABI Wallingford, UK. Pp 193-206.
5. Galac S, Knol BW. 1997. Fear-motivated aggression in dogs: Patient characteristics, diagnosis and therapy. Animal Welfare 6, 9-15.
6. Kobelt AJ. 2004. The behaviour and welfare of pet dogs in suburban backyards. Unpublished PhD thesis. University of Melbourne, Australia.
7. Landsberg G, Hunthausen W, Ackerman L. 1997. Handbook of behaviour problems of the dog and cat. Butterworth Heinemann, Oxford, England.
8. Luescher AU. 2003. Diagnosis and management of compulsive disorders in dogs and cats. The Veterinary Clinics: Small Animal Practice 33, 253-67.
9. Luescher UA, McKeown DB, Halip J. 1991. Stereotypic or obsessive-compulsive disorders in dogs and cats. Veterinary Clinics of North America: Small Animal Practice 21, 401-13.
10. McCobb EC, Brown EA, Damiani K, Dodman NH. 2001. Thunderstorm phobia in dogs: An Internet survey of 69 cases. Journal of the American Animal Hospital Association 37, 319-24.
11. Overall KL. 1997. Clinical behavioral medicine for small animals. Mosby, St. Louis, Missouri, USA.
12. Overall KL, Dunham AE, Frank D. 2001. Frequency of non-specific clinical signs in dogs with separation anxiety, thunderstorm phobia, and noise phobia, alone or in combination. Journal of the American Veterinary Medical Association 219, 467-73.
13. Reisner LR, Erb HN, Houpt KA. 1994. Risk factors for behaviour-related euthanasia among dominant-aggressive dogs: 110 cases (1989-1992). Journal of the American Veterinary Medical Association 205, 855-63.
14. Roll A, Unshelm J. 1997. Aggressive conflicts amongst dogs and factors affecting them. Applied Animal Behaviour Science 52, 229-42.
15. Simpson BS. 2000. Canine separation anxiety. Compendium for Continuing Education for Practicing Veterinarians 2, 328-37.
16. Stafford K. 2006. The welfare of dogs. Springer Dordrecht, The Netherlands.
17. Voith VL,d Borchelt PL. 1996. Separation anxiety in dogs. IN Readings in Companion Animal Behaviour, edited by V.L. Voith and P.L. Borchelt. Veterinary Learning Systems, New York, USA. Pp 124-39.