Estimation of Live Weight by Body Measurements in the Miranda Donkey Breed

The use of the measurement of heart girth (HG), in locations where a scale is not available, with the application of weight estimation formulas or special weight tapes, is well established as a practical and accurate way to estimate the live weight (LW). Although several studies were performed to correlate donkey body measurements and LW, none of these was done in the large frame European donkey breeds. When using smaller frame breeds formulas, the tendency was to underestimate the live weight of larger frame breeds. The sample used in this study consisted of 65 Miranda breed donkeys, with ages ranging from 4 days to 15.4 years (6.6 ± 4.4 years). The studied population mean LW was 280.8 ± 106.1 kg (32.5-475.5 kg); the mean height was 127.4 ± 14.7 cm (69-157.5 cm); the mean body length (BL) was 131.4 ± 25.3 cm (59-184 cm); and the mean HG was 143.8 ± 23.1 cm (71-175 cm). All the correlations between LW and the body measurements taken were statistically significant (P < .001), but the degree of accuracy was higher in the HG (r = 0.937) than in the BL (r = 0.915) or height (r = 0.894). The formula that best estimates the LW was performed by Quadratic model and was based on the HG measurement: LW = 98.138-3.0386 × HG + 0.0293 × HG² (LW in kilogram; HG in centimeter). The formula found can be used to create a weighing tape, adapted to large frame European donkey breeds, to be used to estimate weight and better adapt medication dosages and carried load for each animal.