Comparative analysis of ultradian and circadian behavioural rhythms for diagnosis of biorhythmic state of animals

A chronobiological procedure has been developed for evaluation of living co nditions, behaviour and internal state of free-ranging animals. It is based on continuous recordings of activity and feeding with subsequent compariso n of levels, daily patterns as well as daily and ultradian rhythms. Telemet ric observations were carried out on alpaca, sheep, Przewalski horse, roe d eer, red deer and mouflon under various conditions. The time patterns of th e different species were analysed macroscopically and by autocorrelation fu nction and power spectral analysis. A stable ultradian structure of behavio ur was obvious especially for ruminants. A more unstable, adaptive time pat tern was found in Przewalski horses. Activity as a multi-purpose behaviour was generally more variable than feeding which in most cases was of clearly rhythmic and harmonic structure. Degrees of Functional Couplings (DFCs) we re used for comparison of rhythmic structure. DFCs express the percentage o f the circadian component and harmonic ultradian components in relation to all rhythmic components of a spectrum. They were Found to be high in well a dapted, healthy and undisturbed individuals but were lowered during periods of adaptation, sickness or social interactions.