Inbreeding, phenotypic traits, coat colours and prevalence of health problems in a population of English Cocker Spaniels: the first survey in Italy

This paper presents a survey on inbreeding (F), phenotypic traits, coat colours and prevalence of health problems in a population of English Cocker Spaniels. The aims were to analyse the health and genetic variability of the population and to check whether the population falls within the standards for the breed from a morphological point of view. In addition, we studied the influence of F on phenotypic traits and on the occurrence of various genetic diseases (progressive retinal atrophy, familiar nephropathy, hip dysplasia, patellar luxation and the juvenile renal dysplasia). All data were collected in relation to 83 adult (mean age 4.42 ± 2.528 years) dogs (20 males and 63 females) born in the period 2011–2018 and belonging to one Italian breeder. The F of each dog and other genealogical parameters were calculated. The prevalence of each highlighted disease within the population was performed. ANOVA was used to test the differences in F values among the animals subdivided into different groups (healthy and un-healthy dogs, coat colour, birth year and sex). Differences between sexes in morphological traits and proportions were also analysed showing sexual dimorphism. The predominant colours were Blue-Roan (30.12%) and Red (26.51%). We found an excellent health status and a good genetic variability of the analysed population. The only disorder that caused concern was juvenile renal dysplasia (26.51%, 95% CI 14.27–38.74%). A relationship was suggested between inbreeding and the disorder as F was significantly higher (P < 0.01) in sick (F = 0.068) than in healthy animals (F = 0.014).