There is increasing interest in evaluating how chronic disease may affect dogs through assessment of their behavior in their everyday environment.1–4 Many chronic conditions can cause changes in a dog's activity. Conditions such as cardiac disease and osteoarthritis can compromise mobility, whereas a condition such as pruritus could increase an animal's activity.1–4 An objective method of quantifying the activity of companion dogs in their routine environment could be a useful tool for monitoring progression of disease or the efficacy of a treatment . In addition, extent of activity directly affects an individual dog's energy balance and factors into that dog's caloric requirement, so an objective means of quantifying activity might also be useful for tailoring feeding recommendations to better reflect a companion dog's opportunity and inclination to exercise.
An accelerometera has been developed that can continuously record the intensity, frequency, and duration of movement for extended periods. This device has been used to monitor the activity of laboratory dogs (principally Beagles) in several investigations.5–8 One study, determining locomotor activity rhythms in laboratory dogs, revealed that the dogs' activity was dependent on their housing environment.5 The size of the housing area and the type of facility (indoor vs partially outdoor) influenced the dogs' activity. Variability of environment is certainly an issue to consider if accelerometers are to be used as an objective measure of activity in companion dogs.
Companion dogs, in contrast to laboratory dogs, are generally housed in considerably different environments, which can vary substantially among individual households. Also, the daily routine of laboratory dogs is uniform regardless of the day of the week, unlike that of companion dogs, which may vary from day to day and could be influenced by the activities of their owners. In addition, the kinds of activity in which companion dogs participate are likely to be much more variable and uncontrolled in comparison to laboratory dogs. If the greater variability in the environment and routine of companion dogs led to greater variability in the counts delivered by the accelerometer during home activity monitoring, it would be difficult to use this device to monitor changes in response to an intervention because important changes may occur even when there is no intervention at all.
Presently, this activity monitor has not been validated for use in companion dogs in their home environment for an extended period of time. A necessary step in this validation is to determine whether the activity counts delivered by this device are consistent from one sampling interval to the next in dogs that are in their routine home environment (ie, no nonroutine activities such as vacations, activities associated with house sitters, or activities associated with additions of new dogs). Before this monitor can be used to detect changes in dogs' activity associated with an intervention, the kind of changes in activity counts one could expect with no intervention must be known, so that the sampling interval that delivers the least variable activity counts from one assessment to the next can be used for future studies.
The purpose of the study reported here was to determine by use of an accelerometer which sampling interval provided the least variable total activity counts from one week to the next in companion dogs. We hypothesized that total daily activity counts recorded by an activity monitora would be highly variable among individual dogs and that within a group of companion dogs, there would be significant day-to-day variability in total activity counts, which would be most pronounced on weekends when there is potentially more interaction with owners. We also hypothesized that the day-to-day variability could be overcome by comparing total activity counts in 7-day intervals.
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Freeman LM, Rush JE, Farabaugh AE, et al. Development and evaluation of a questionnaire for assessing health-related quality of life in dogs with cardiac disease. J Am Vet Med Assoc 2005;226:1864–1868.
Wiseman-Orr ML, Nolan AM, Reid J, et al. Development of a questionnaire to measure the effects of chronic pain on health-related quality of life in dogs. Am J Vet Res 2004;65:1077–1084.
Nuttall T, McEwan N. Objective measurement of pruritus in dogs: a preliminary study using activity monitors. Vet Dermatol 2006;17:348–351.
Siwak CT, Tapp PD, Zicker SC, et al. Locomotor activity rhythms in dogs vary with age and cognitive status. Behav Neurosci 2003;117:813–824.
Siwak CT, Murphey HL, Muggenburg BA, et al. Age-dependent decline in locomotor activity in dogs is environment specific. Physiol Behav 2002;75:65–70.
Siwak CT, Tapp PD, Milgram NW. Effect of age and level of cognitive function on spontaneous and exploratory behaviors in the beagle dog. Learn Mem 2001;8:317–325.
Hansen BD, Lascelles BDX, Keene BW, et al. Evaluation of an accelerometer for at-home monitoring of spontaneous activity in dogs. Am J Vet Res 2007;68:468–475.