Computed Tomographic Assessment of Body Fat in Dachshunds: A Pilot Study

Obesity has not been linked to causing intervertebral disc degeneration, but has been shown to influence time to ambulation, a strong long-term prognostic indicator in dogs with intervertebral disc disease. However, monitoring obesity to date is imprecise and subjective in the clinical setting. Having an objective formula based on morphometric measurements would potentially be more precise to track our patients' weights. Dogs have been shown to gain weight along their lumbar spine more rapidly than other areas. Varying body conformations make extrapolation from nonchondrodystrophic dogs to Dachshunds difficult. This study aimed to establish the region of fat accumulation along the thoracolumbar spine in Dachshunds. Retrospective computed tomographic (CT) analysis was performed on healthy Dachshunds that presented for intervertebral disc disease (IVDD). Fat area measured at L3 and L5 using attenuation ranges -135/-105 Hounsfield units (HU) was the most dependent on body weight (p = 0.05). There appeared to be no difference between subcutaneous, visceral or total percent body fat with weight agreement. T13, L3 and L5 all had linear relationships with patient weight and will likely be helpful for body mass index (BMI) formula creation (p < 0.01). This study indicates that any consistent location between L3 and L5 will give an accurate representation of the abdominal circumference and most obese area of the Dachshund with the umbilicus used as a landmark.