Comparative analysis of walking gaits in South American camelids

Abstract

Although several studies on the locomotion of Old World camels, mainly the dromedary Camelus dromedarius, exist, detailed data on their relatives, the New World camelids are very scarce. Camelids are distinguished from most mammals by their pacing gaits, a pace-like walk and running pace. We conducted detailed video analyses of undisturbed walking in the alpaca Lama pacos and llama Lama glama and compared these with observations of the dromedary and domestic warmblood horses Equus caballus. The average walking speed, stride length and stride frequency (mean±sd) were 0.97±0.15 m s−1, 0.94±0.08 m and 1.03±0.08 s−1 for alpacas and 1.13±0.12 m s−1, 1.18±0.08 m and 0.95±0.05 s−1 for llamas, respectively. The mean support phase (mean±sd) was 0.67±0.11, 0.72±0.10 and 1.11±0.14 s for llama, horse and dromedary, respectively, corresponding to 58.9±3.8, 61.7±3.2 and 66.0±1.2%, respectively. We found remarkable differences between New and Old World camelids. Contrary to the dromedary, alpacas and llamas in our study did not perform a symmetrical running pace. The lateral time lag was shortest in the llama, decreasing with increasing speed from 15 to 5% with an average of 10%.