Evaluation of indirect methods for estimating body fat in dogs using electrical bioimpedance and morphometry
Daniel Montoya-Barbosa1, Clara Helena González-Correa2, William Narváez-Solarte1,3
1Master in Veterinary Sciences, Universidad de Caldas, Manizales, Colombia.
None:
Canine obesity causes metabolic issues and reduces quality of life. Assessing adiposity remains challenging due to limited indirect and reference methods. Electrical bioimpedance (BIA) is a proposed tool, but agreement between morphometric and BIA equations, and the body condition score (BCS) role, remains poorly explored in heterogeneous canine populations.
Objective:
To evaluate agreement among indirect methods (BCS, morphometry, BIA) for estimating canine body fat and assess BIA's viability for nutritional evaluation.
Materials And Methods:
A cross-sectional study included 17 healthy dogs from Villamaría, Colombia. Body condition was assessed using 5- and 9-point scales. Morphometric variables and single-frequency 50 kHz BIA parameters (resistance, reactance, phase angle) were recorded. Body fat percentage (%BF) was estimated using four established equations. Method agreement was evaluated via Bland-Altman analysis and Lin's concordance correlation coefficient (CCC). Differences in bioelectrical parameters and lipid profiles between obese and lean dogs were analyzed using independent t-tests.
Results:
Morphometric methods showed the highest agreement (CCC = 0.759). Conversely, comparisons involving BIA-derived equations exhibited low or negative agreement, with Bland-Altman analyses revealing wide limits of agreement. Obese dogs had higher resistance and lower phase angles than lean dogs, though differences were not statistically significant (p > 0.05). This lack of significance must be interpreted cautiously due to the small sample size, particularly the obese group (n = 4). HDL cholesterol was significantly lower in obese dogs (p = 0.030), with no differences in total cholesterol.
Conclusion:
The evaluated indirect methods showed poor agreement and are not clinically interchangeable. Without a reference method like DEXA, accuracy cannot be determined. While raw BIA parameters aligned physiologically with body condition, their use remains preliminary and requires validation in larger, reference-controlled studies.
