A brief note about cow lying behaviour-Do cows choose left and right lying side equally?

The factors influencing cows' lying behaviour are not fully evaluated. Most studies dealing with lying behaviour were primarily aimed at comparing different designs for the resting area and floor surfaces, while only a few studies have investigated the cows' preference of lying side. The aim of the present investigation was to test the hypothesis that cows choose equally between left and right lying-side. The study consisted of three experiments, where two were performed in a loose house system with automatic milking (AM) and only lactating cows participating, and the third was carried out on pasture. In the first and second study the herd consisted of 45-47 cows of the Swedish Red and White breed. The behaviour observations during the first study were made every 20 min in 18 periods of 4 h each. During the second study, cows were manually identified every 12 min during 4 periods of 48 h each. In the third study, observations were randomly performed during the day time for 59 days. In the study out on pasture at gestation month 9, the frequency of observations where cows were lying on the left side was significantly higher (p < 0.012) than lying on the right side. In the two studies performed in the AM system the cows chose left and right laterality equally. No effect of age was seen on the choice of lying side. In the resting area, the cows lay with the ventral side against the activity area. (C) 2008 Elsevier B.V. All rights reserved.