Evaluation of coronary band temperatures in healthy horses

Abstract Objective—To measure coronary band temperature (CBT) in healthy horses fed high-fructan or low-carbohydrate diets and to analyze the association of CBT with diet, time of day, and ambient temperature. Animals—6 healthy horses. Procedures—Horses were fed 3 diets (treatment 1, 1 g of fructan/kg fed daily in the morning; treatment 2, 1 g of fructan/kg fed daily in the afternoon; and treatment 3, a low-carbohydrate [7.2%] diet) in a 3 × 3 Latin square study design. For each horse, the CBT of all 4 limbs as well as rectal and ambient temperatures were recorded by use of infrared thermometry and standard thermometers hourly from 8 am to 10 pm for 4 consecutive days after the initiation of each diet. Each horse received each diet, and there was a 10-day washout period between each diet change. Data were analyzed by use of a mixed linear model. Results—4,320 CBTs were obtained from the 6 horses. The CBT ranged from 9.6° to 35.5°C. Coronary band temperature followed a diurnal pattern and was positively associated with ambient temperature but was not associated with diet. Conclusions and Clinical Relevance—CBT of healthy horses varied significantly during the day and among limbs. These results should be considered whenever increased CBT is used as an indication of incipient laminitis or in other clinical investigations.