Artificial selection has been employed for centuries in the context of domestication. Dogs were primarily selected for an ability to interact well with humans, thus enabling them to succeed in the human realm (McGreevy & Nicholas 1999).
Most of the traits subject to artificial selection were initially for functionality. However, humans have extensively altered the phenotype of the modern dog beyond that of any other domestic species (McGreevy & Nicholas 1999), and it is when this selection is administered for the benefit of humans that it becomes implicated in the health and welfare of the animal. Pedigree dogs have been bred to conform to some published, aesthetic ideal through generations of inbreeding to so-called ‘stud’ dogs (Summers, et al 2009), for the financial gain of the owner Whilst the Summers paper considers the effects of inbreeding, and demonstrates that the rate of inbreeding within these pedigree dogs is 0.66% per generation, it fails to show that the loss of heterozygosity within an inbred population decreases by half each generation. This effect is more pronounced in small populations, such as these pedigree dogs. Inbreeding may intensify health problems, by increasing the prevalence of recessive disorders associated with musculoskeletal, respiratory and immune defects (Asher, et al 2009). It is obvious that the reduction of heterozygosity within highly inbred species selects for the appearance rather than function or health of the animal (Asher, et al 2009). Such animals are predisposed to harm in health and welfare, and the fundamental cause is for the benefit of