Kinematics of forward and backward locomotion performed in different environmental conditions

Abstract

Mice are frequently used in analyses of the locomotor system. Although forward locomotion (FWL) in intact mice has been studied previously, backward locomotion (BWL) in mice has never been analyzed. The aim of the present study was to compare kinematics of FWL and BWL performed in different environmental conditions (i.e., in a tunnel, on a treadmill, and on an air-ball). In all setups, the average speed and step amplitude during BWL were significantly reduced compared with FWL. The cycle duration varied greatly during both FWL and BWL. The average swing duration during BWL was twice shorter than during FWL on each setup. Mice exhibited different interlimb coordinations (trot and walk with lateral or diagonal sequence) during BWL but only one gait (walk with lateral sequence) during FWL. Location of the rostro-caudal paw trajectory in relation to the hip projection to the surface (HP) depended on hip height. With low hip height, the trajectory was displaced either rostrally (anterior steps) or caudally (posterior steps) to HP. With high hip height, HP was near the middle of the trajectory (middle steps). During FWL, all three forms of steps were observed in the tunnel and predominantly anterior and posterior steps on the treadmill and air-ball, respectively. During BWL, only anterior steps were observed. Intralimb coordination depended on the form of stepping. Limb joints were coordinated to keep the hip at approximately constant height during stance and to have the smallest functional limb length during swing when the limb passed under the hip. NEW & NOTEWORTHY Mice are extensively used for the analysis of the locomotor system. This study is the first examination of the kinematics of forward and backward locomotor movements in different environmental conditions in mice. Obtained results represent a benchmark for studies based on manipulations of activity of specific populations of neurons to reveal their roles in control of specific aspects of locomotion.

Differential Contribution of V0 Interneurons to Execution of Rhythmic and Nonrhythmic Motor Behaviors

“…The general characteristics of BW locomotor movements obtained in the present study (locomotor speed, frequency of locomotor movements, step amplitude, duration of the stance, and swing phases) in wild-type mice (Fig. 2A,B) were similar to those reported earlier for wild-type mice performing BW locomotion in similar environmental conditions (Vemula et al, 2019).…”

“…BW locomotion was performed in a tunnel setup (Fig. 1A) described previously (Vemula et al, 2019). It was made of transparent Plexiglas and imitated the narrow tunnels of the burrows in which mice live in nature.…”

“…These behaviors require left-right coordination mediated by yet unknown neuronal mechanisms. BW locomotion and scratching are both rhythmic movements, but BW locomotion involves leftright limb alternation (Buford et al, 1990;Vemula et al, 2019), while scratching movements are performed by only one hindlimb (Deliagina et al, 1975;Kuhta and Smith, 1990;Inagaki et al, 2001). However, strong reciprocal inhibition between the left and right scratching networks has been suggested (Deliagina, 1977).…”

Pycnogenol improves kinematic parameters of donkeys (Equus asinus) subjected to packing during the dry season

“…Thus, evaluating changes in the locomotion of donkeys especially after subjecting them to packing is pertinent in order to detect fatigue. Kinematic analyses have been used to study speed in Equidae, especially horses (Michael et al, 2007;Egenvall et al, 2020) and it describes the geometry of animal movement including changes in the positions of the body parts (Volchenkov et al, 2014;Vemula et al, 2019). Quantitative analytical methods which include standard motion capture systems and a high-speed treadmill (Algheshyan et al, 2014) have been used to study locomotion in Equidae under laboratory conditions.…”

“…However, even though these systems are highly accurate, they are very expensive and require a dedicated facility for data collection and this makes them unsuitable for studying locomotion in animals especially under field conditions. This informed the use of videographic gait analysis in this study (Vemula et al, 2019), in order to evaluate fatigue which may be caused by physical exertion. Kinematic analysis can be used to perform standard lameness assessment by observing walking gait in order to implement and monitor interventions in working donkeys (Serra Braganca et al, 2020).…”