Establishing the extent of behavioural reactions in dairy cattle to a leg mounted activity monitor

Tri-axial accelerometers, typically used in activity monitors for detecting oestrus events in dairy cattle, are potentially a valuable device in the ethologist's toolbox. They open up the possibility of monitoring large numbers of animals over long periods of time with minimum human intervention. The use of such devices on domesticated cattle is widespread, however there is little systematic information available on how the animals react to being ‘tagged’. Typically accelerometers are attached to a hind limb. In this study, the behaviour and feed intake of 28 lactating dairy cattle (sound n = 22, lame n = 6) was observed in housed cows for three consecutive periods: a baseline period, a period without accelerometers and a period with accelerometers. The effect of being tagged on the behaviour of the animal and whether habituation occurred within the tagged period were investigated. There was no evidence of a general change in feed intake (P = 0.438), in the proportion of time spent lying (P = 0.703) or proportion of time spent lying on the untagged side (P = 0.708) between tagged or untagged periods. All animals showed an increase in time spent standing and decrease in time spent lying over the first two tagged days, which became non significant by Day 3, when compared to the last untagged day (lying P = 0.575, standing P = 0.974), suggesting a habituation period of two days after tagging for animals to adjust to wearing the tags. From these results, the authors conclude that accelerometers are a non-invasive tool for the study of cattle behaviour, but recommend that data may not be reliable until two days after the attachment of the device.