Manal B. M. Hemida, Siru Salin, Kristiina A. Vuori, Robin Moore, Johanna Anturaniemi, Sarah Rosendahl, Stella Maria Barrouin‐Melo, Anna Hielm‐Björkman. Puppyhood diet as a factor in the development of owner‐reported allergy/atopy skin signs in adult dogs in Finland. Journal of Veterinary Internal Medicine, 2021; 35 (5): 2374 DOI: 10.1111/jvim.16211
Atopic dermatitis (AD) in dogs is usually defined as an inflammatory allergic skin disease that begins during the first 3 years of life.1, 2 The worldwide AD prevalence in dogs was estimated to be approximately 10%-15% in 2001.3 In 2017, an owner-reported AD prevalence of 18.3% was reported in an earlier version of our own questionnaire data.4 This high prevalence makes exploring the disease etiology and possible preventive measures important, as although AD affects dogs with genetic predispositions for the disease, genetics alone cannot justify the increased prevalence over the last few years.2-4
Early life environmental exposures, such as diet have been found to impact the development of the immune system and subsequently disease susceptibility later in life in both animals and humans alike.5, 6 This was first proposed by Strachan7 who suggested that a lack of microbial exposure during childhood explains the increased prevalence of allergic diseases. Such exposures are supposed to be essential for programming the immune system and modifying its future inflammatory responses.8 In light of the hygiene hypothesis, a reformulated hypothesis, known as the “microflora hypothesis,” has been proposed. It argues that early life exposures to beneficial nonpathogenic microbes can alter the individual's microbiome development, influence the innate and adaptive immune system, and cause permanent consequences for the individual's health.9, 10
Deworming the dams during pregnancy, sunlight exposure, normal body condition score, born in the same family where the dog lives, and exposure to rural environment have all been found to decrease owner-reported AD prevalence.11 Additionally, other genetic and background factors such as the maternal history of owner-reported AD, age, sex, breed, and color have previously been studied.11 In the study on the modifiable early risk factors for AD development in dogs, we reported that maternal and puppyhood diets based on nonprocessed meat were significantly associated with a decreased prevalence of owner-reported AD, while a diet based on ultraprocessed carbohydrate-rich foods were significantly associated with an increased risk for owner-reported AD.11 The nonprocessed meat/ingredients at early life may lead to microbial exposure that enhances the immune system's maturation which thus may help mitigate allergies.11 A study on humans reported that the consumption of unpasteurized milk during childhood was associated with a lower prevalence of AD when compared with the consumption of pasteurized milk.12 Research that show the similarities between canine and human AD, including the increased prevalence, clinical manifestations, diagnostic standards,5 and host-microbiome interaction,6 highlight that the dog is an ideal model for studying, for example, AD pathogenesis.6
The aim of the current study was to investigate the association of puppyhood dietary exposures with later owner-reported allergy/atopy skin signs (AASS) incidence using a broad range of food items reported by the owners in a food frequency questionnaire.