The study highlights the importance of what dogs eat. Based on data collected through an online questionnaire over several years (DogRisk FFQ, a copy available at: http://bit.ly/427aGBa), the study observed that feeding dogs a natural raw non-processed meat-based diet (NPMD), during pregnancy and their early and late puppyhood significantly lowered the risk of otitis. Conversely, if a dog's diet consisted mainly of commercial dry dog food (kibbles), referred to as an ultra-processed carbohydrate-based diet (UPCD) in the article, during these critical periods, it increased the risk of otitis. Moreover, the study revealed other domestic and environmental key factors that affect a dog’s ear health. Dogs that stay with their original families tend to have less otitis later in life compared to those that have moved to new homes. Both diet and environment effects suggest that there is an immune tolerance that builds up during this critical young puppy age. Also, dogs that got at least an hour of sunlight every day as a young puppy tended to have less otitis later in life than those with little or no sunlight exposure. The study also suggests that the type of flooring during a dog's later puppyhood may impact ear health. Dogs raised on dirt or grass tended to have a lower risk of otitis than those raised on other floor types. Genetics and breed factors were also covered by the study: dogs that had a maternal history of otitis and dogs from otitis prone breeds had a higher risk of otitis later in life compared to those without a maternal history of otitis and those from non-otitis prone breeds.
Dr. Manal Hemida from the Helsinki One Health network and the main researcher behind the study, commented, "Our findings show that choosing a species-appropriate dog diet, in our study this was raw food, together with an outdoor lifestyle might significantly decrease the risk of otitis. While more research is needed to understand the exact mechanisms, it’s essential for dog owners to be aware of these factors, which allows them to take appropriate preventive measures already now. Our research also impacts human research, e.g. otitis in children, and the results concerning the negative effects of a too strict hygiene are the same in both species", Hemida continues.
Adjunct Professor Anna Hielm-Björkman, the principal investigator of the study, leader of the DogRisk research group, comments, "To promote healthy ears, our study suggested that at least a quarter of a dog's diet should be raw food, while kibble should make up less than three-quarters." Dr. Hielm-Björkman continues "While our findings suggest a strong association between early-life factors and otitis risk, to prove causality we need clinical research. In this sad time after a major withdrawal of dog food in Finland, I think we can all see the need of investing in dog food research."
Hemida MBM, Vuori KA, Borgström NC, Moore R, Rosendahl S, Anturaniemi J, Estrela-Lima A and Hielm-Björkman A (2023) Early life programming by diet can play a role in risk reduction of otitis in dogs. Front. Vet. Sci. 10:1186131. doi: 10.3389/fvets.2023.1186131