How do cattle respond to sloped floors? An investigation using behavior and electromyograms

Abstract

On dairy farms, flooring is often sloped to facilitate drainage. Sloped floors have been identified as a possible risk factor for lameness, but relatively little is known about how this flooring feature affects dairy cattle. Ours is the first study to evaluate the short-term effects of floor slope on skeletal muscle activity, restless behavior (measured by number of steps), and latency to lie down after 90 min of standing. Sixteen Holstein cows were exposed to floors with a 0, 3, 6, or 9% slope in a crossover design, with a minimum of 45 h between each testing session. Electromyograms were used to evaluate the activity of middle gluteal and biceps femoris muscles. Muscle activity was evaluated in 2 contexts: (1) static muscle contractions when cows continuously transferred weight to each hind leg, before and after 90 min of standing; and (2) dynamic contractions that occurred during 90 min of treatment exposure. Median power frequency and median amplitude of both static and dynamic muscle electrical signals were calculated. Total muscle activity was calculated using the root mean square of the signals. Restless behavior, the number of steps per treatment, steps and kicks in the milking parlor, and the latency to lie down after the test sessions were also measured. It was predicted that restless behavior, muscle fatigue (as measured by median power frequency and median amplitude), total muscle activity, and latency to lie down after testing would increase with floor slope. However, no treatment differences were found. Median power frequency was significantly greater for the middle gluteal muscle [35 ± 4 Hz (mean and SE)] compared with the biceps femoris muscle (24 ± 3 Hz), indicating that the contractive properties of these muscles differ. The number of steps per minute and total muscle activity increased significantly over 90 min of standing, irrespective of floor slope. Although restless behavior and muscle function did not change with slope in our study, this work demonstrates that electromyograms can be used to measure skeletal leg muscle activity in cattle. This technology, along with restless behavior, could be useful in assessing cow comfort in other situations, such as prolonged standing.

Effect of rubber flooring on dairy cattle stepping behavior and muscle activity

“…Regardless of floor type or presentation method, cattle did not experience fatigue (as measured by changes in MPF and MA) over the 1 h of standing. Similarly, when SEMG were used on cows to evaluate muscle fatigue, there was no indication of fatigue when comparing MPF and MA values at the start and end of 90 min standing (Rajapaksha and Tucker, 2014) and 1 h of standing (Rajapaksha and Tucker, 2015). In the current study, significant MPF reduction was observed on the concrete surfaces without corresponding MA increase; thus, this change did not meet the definition of fatigue used by Luttman et al (2000).…”

“…Eight self-adhesive bipolar surface electrodes (3M Red Dot Repositionable Electrodes, Ag/AgCl) were attached on the skin over the middle gluteal muscle (an extensor of the hip joint and abductor of the leg that controls hip movements) and the biceps femoris muscle (extensor of the hip and stifle and flexor of the stifle) muscle on both right and left sides of the cow. Details of skin preparation and electrode placement are explained in our previous work (Rajapaksha and Tucker, 2014). An electromyography telemetric system (Megawin Biomonitor ME 6000, Mega Electronics Ltd., Kuopio, Finland) was used to record SEMG readings during both static and dynamic muscle contractions.…”

“…Static contractions were measured in the standing stalls while the cows were standing on the treatment surfaces both before and after the 1 h of testing. To generate static contractions, cows were forced to transfer their weight to this hind leg by placing a wooden board with fixed carriage bolts covered by a thin rubber mat (Rajapaksha and Tucker, 2014) under the other hind leg. During this process, a wooden board was placed under the other hind leg to avoid any direct effects of the treatment standing surface on the static-contraction reading (i.e., on 3-1ROUGH when one hind leg had rough surface).…”

Stepping behavior and muscle activity of dairy cows on uncomfortable standing surfaces presented under 1 or 4 legs

“…The research on responses to standing can be divided into 2 methods of presentation: evaluation of flooring features where all 4 legs are on standard surfaces (e.g., concrete or rubber), and where only 1 leg experienced something different, such as pain or exposure to alternative flooring. Experiments that present treatments under all 4 legs have used stepping rate to examine the effect of standing time (Cooper et al, 2007), floor slope (Rajapaksha and Tucker, 2014), or surface compressibility (Krebs et al, 2011;Chapinal and Tucker, 2012). In all of these experiments, steps increased over time, but no differences were observed between flooring treatments.…”

Use of electromyography to detect muscle exhaustion in finishing barrows fed ractopamine HCl1

“…Fatigue in other livestock species has been measured via EMG (Girsch et al, 1995;Robert et al, 2000;Lee et al, 2013;Rajapaksha and Tucker, 2014), but these studies did not explore the biological characteristics of the muscle responsible for fatigue. Therefore, the objectives of this study were to use a RAC diet feeding model to induce muscle exhaustion in barrows, measure muscle fiber activity via EMG, and relate differences in exhaustion to muscle fiber type characteristic differences.…”