Abstract
This paper describes how often pet dogs interact with other dogs, people and the environment, whilst being walked. Such interactions may involve aggression or the transmission of infectious disease. We also assessed the effect of the use of a leash as a modifier of these outcomes. In study one, the behaviour of pet dogs being walked in popular public walking areas was observed (286 observations). Interactions with people were much rarer than interactions with dogs. Multivariable modelling suggested that percentage duration spent sniffing the ground was associated with the UK Kennel Club Breed Type, and whether the dog was observed urinating. Gundogs were observed to sniff more than other breed types. In study two, dogs (n = 10) were filmed twice walking along a pre-defined route, alternately once on leash and once off leash, in order to assess the effects of leash use on interactions between the subject dog and any other dog or person encountered. Multilevel modelling suggested that if either dog was on the leash, then the likelihood of an interaction with a dog occurring was reduced. There was no evidence for statistical interactions between these variables, therefore the effect of the leash on one dog did not seem to be influenced by whether the other dog was on or off leash. We conclude that in circumstances where interactions need to be prevented, such as to reduce spread of infectious diseases during an outbreak, both dogs should be leashed.