Abstract
BACKGROUND: Dental calculus (DC) in dogs is a common oral health issue that can result in discomfort and may lead to systemic complications, if not managed effectively. While dental care practices are often overlooked by many owners, it remains crucial to identify and address possible DC risk and protective factors. The present retrospective cross-sectional study sought to examine the early life factors contributing to the emergence of owner-reported DC in dogs later in life, emphasizing the impact of modifiable variables. The study examined exposure data across five pivotal early life stages, starting prenatally and extending into adolescence. Multivariate logistic regression analyses using backward stepwise deletion were performed using data from 4771 dogs, including 2360 cases and 2411 controls, to examine the potential associations between DC in dogs and 29 distinct early life variables across five statistical models. The study incorporated a range of independent variables, including dietary, environmental, demographic, domestic, and immune-related factors. Additionally, the study aimed to compare between energy value and macronutrient composition of non-processed meat-based diets and ultra-processed carbohydrate-based diets available on the Finnish market. RESULTS: Our research indicated that dogs fed a non-processed meat-based diet during the weaning period, puppyhood, and adolescence, which corresponds to the age range of 1 month to 1 or 1.5 years, were associated with a significantly lower risk of developing DC later in life. Conversely, dogs consumed an ultra-processed carbohydrate-based diet during the same periods was associated with a significantly higher risk (p = 0.01, p = 0.001, and p = 0.02 for weaning, puppyhood, and adolescence, respectively). Additionally, residing with other dogs was significantly associated with a decreased likelihood of DC development later in life (p = 0.015). Moreover, from the non-modifiable factors model, a maternal history of DC and small size of the dog were strongly associated with an increased risk of DC development later in life. CONCLUSIONS: In addition to the well-known non-modifiable risk factors, such as age and size of the dog, the current study revealed potential associations between modifiable early life exposures and development of DC later in life, including early diets and living with other dogs. However, controlled diet-intervention studies remain necessary to substantiate these connections. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12917-025-04885-8.