VN October 2021

Vetnuus | Oktober 2021 8 Brachycephalic (flat-faced) breeds have experienced a significant increase in global popularity in recent years, despite well- documented intrinsic health and welfare problems associated with their conformation 1 . Canine and feline brachycephaly is a manmade trend, resulting from artificial selection and breeding for extreme characteristics with marked inbreeding. When people selectively breed for conformational extremes, unexpected deleterious effects to the welfare of those animals frequently become evident over time 2 . Breed popularity is associated more with the animals’ physical appearance as opposed to welfare- related breed characteristics (e.g., general health and longevity), meaning that brachycephalic breeds with increased prevalence of inherited disorders are becoming more popular. There is no single definition for brachycephalism: skull width-to-length ratio and the craniofacial ratio are considered as part of the definition. However, variation within some breeds means the term is best suited for individual animals rather than breeds as a whole 3 . Breeds commonly associated with brachycephalism are pugs, French and English Bulldogs, Boston terriers, Pekinese, boxers and Persian cats. Owners of brachycephalic breeds will expound on the wonderful natures and appealing looks of these breeds. It has been suggested that the typical childlike facial features of brachycephalic breeds (rounded skull, large eyes and bulging cheeks) trigger the same attraction and nursing response as babies do in adult humans 3 . Ownership of these breeds is a complex phenomenon, characterised by extremely strong owner-pet relationships. These owners often have unrealistic expectations of their pets’ good health when compared to the high prevalence of disease in relatively young dogs 1 . By a lack of genetic diversity, animals bred for certain conformational traits are put at an increased risk of pain, suffering, injury and/or disease 4 . Brachycephalic breeds, especially dogs, are plagued by various pathological processes which arise from their conformation and compromise their individual welfare. These include respiratory disease (Brachycephalic Obstructive Airway Syndrome; BOAS), heatstroke, ocular problems (wide, shallow orbits predispose to corneal ulcers and globe prolapse), dystocia, dermatological disease, spinal abnormalities and obesity and joint problems 1,3 . Brachycephalic Breeds and Associated AnimalWelfare Concerns Figure 1: Canine cranioskeletal shape. (A) Shetland sheepdog (dolichocephalic); (B) Labrador retriever (mesaticephalic); (C) bulldog (brachycephalic); (D) French bulldog (brachycephalic). From Ekenstedt et al. (2020). Article