## 4 Discussion  
Regulatory compliance for labelling is required for commercial pet foods marked as complete. Pet food labels offer valuable insights into product details and serve as a crucial resource for pet owners when determining how to nourish their pets. However, studies analyzing the use of pet food labels have indicated that fewer than 40% of pet caregivers consistently review these labels when making feeding decisions [50], although this may have changed in recent years as consumers have become increasingly aware. While, in our study, all the tested canned dog foods were in line with the recommended levels of macronutrients stated in the nutritional guidelines [33], significant discrepancies were observed between the manufacturer's label declarations and the results of the chemical analysis. Among the analytical constituents, discrepancies in ether extract and crude protein contents were the most prevalent in the canned dog foods evaluated in this study (70% and 50% of the tested canned dog foods were inconsistent with the manufacturer's claims for EE and CP, respectively). More specifically, in 40% of the products, the measured ether extract content was found to be higher than that declared. While the FEDIAF guidelines do not specify a maximum recommended fat intake, the NRC [34] suggests a safe upper limit (SUL) of 82.5 g fat/1000 kcal for dogs. This recommendation is based on evidence indicating a potential association between high-fat diets and the development of acute pancreatitis in dogs [51; 52]. It is important to note that this relationship has not been definitively established [53]. Nevertheless, it is advised to avoid feeding commercial high-fat diets to dogs at a heightened risk of developing acute pancreatitis or those with altered lipid profiles, such as obese dogs [54]. Alarmingly, among the canned dog foods evaluated in this study, one dog food intended for growth (18_P_GF) provided significantly less crude protein (\(-\)15.4%) while containing more ether extract (+36.9%) than what the manufacturer stated on the label. Feeding dogs a high-fat, high-energy, low-protein diet can lead to insufficient protein (and amino acid) intake or an excess of energy [55]. Providing such food to a puppy can be harmful to their growth and may have lasting consequences on their future adult lives. Research conducted on rats [56] has demonstrated that a high-fat, low-protein diet may elicit significant physiological, metabolic, and histological changes in rat models, and these alterations appeared to be associated with the development of metabolic syndrome and the potential disruption of cognitive functions in female rats. Fortunately, some previous assessments have confirmed compliance with regulations in the case of pet food, resulting in relatively favorable outcomes. For instance, in the United States, the variation between the protein content indicated on labels and the actual analyzed protein content in pet food was considered to be acceptable [57]. However, in Canada, 11% of dry pet food samples fell below the lower tolerance threshold for protein content [58], while, in our study, three canned dog foods (15%) exhibited protein content below the lower tolerance threshold (Table 3). In these products, the protein content on the label was overestimated by an average of 7.7%. In turn, a similar study conducted in Brazil [59] on canned dog foods found an overestimation of the composition declared on the label compared to the actual content, with the following discrepancies: total protein by 2.6%, ether extract by 1.2%, crude fiber by 3.7%, and crude ash by 6.4%. In our study, for the amount of ether extract, there was an overestimation of the composition declared on the label compared to the actual content in six canned dog foods (by an average of 9.1%) and an underestimation in eight canned dog foods (by an average of 12.0%). We posit that the disparities observed between the label data and the analysis results do not indicate intentional data falsification by the manufacturer.