... behaviour. It is important to take into account the age pat-tern of disease and possible differences in agedistribution across groups when examiningcompeting causes of death, as in this and ... Medicine and Animal Science, Swedish University of Agricultural Sciences, SE-750 07 Uppsala, Sweden, 3Department of Small Animal Clin-ical Sciences, Faculty of Veterinary Medicine and Animal ... accepted 12 April, 2005).Reprints may be obtained from: A. Egenvall, Department of Clinical Sciences, Faculty of Veterinary Medicine and Animal Science, Swedish University of Agricultural Sciences,...